UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2024

or

For the transition period from ___________ to __________

Commission file number: 001-36199

PULMATRIX, INC.

(Exact name of registrant as specified in its charter)

(888) 355-4440

Registrant’s telephone number, including area code

Securities registered pursuant to Section 12(b) of the Exchange Act:

Securities registered pursuant to Section 12(g) of the Exchange Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐ No ☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes ☐ No ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. Yes ☐ No ☒

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Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the registrant’s voting and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was last sold, as of June 30, 2024, the last business day of registrant’s most recently completed second fiscal quarter, was $7,048,862.

As of March 17, 2025, the registrant had 3,652,285 shares of common stock, par value $0.0001 per share, issued and outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

None.

PULMATRIX, INC.

TABLE OF CONTENTS

PART I

Forward-Looking Statements

This Annual Report on Form 10-K contains forward-looking statements. All statements other than statements of historical fact contained herein, including statements regarding our business plans or strategies, projected or anticipated benefits or other consequences of our plans or strategies, projected or anticipated benefits from acquisitions to be made by us, or projections involving anticipated revenues, earnings, or other aspects of our operating results, are forward-looking statements. Words such as “anticipates,” “assumes,” “believes,” “can,” “could,” “estimates,” “expects,” “forecasts,” “guides,” “intends,” “is confident that,” “may,” “plans,” “seeks,” “projects,” “targets,” and “would,” and their opposites and similar expressions, as well as statements in future tense, are intended to identify forward-looking statements. Forward-looking statements should not be read as a guarantee of future performance or results and may not be accurate indications of when such performance or results will actually be achieved. Forward-looking statements are based on information we have when those statements are made or our management’s good faith belief as of that time with respect to future events and are subject to risks and uncertainties that could cause actual performance or results to differ materially from those expressed in or suggested by the forward-looking statements. Important factors that could cause such differences include, but are not limited to:

For a more detailed discussion of these and other risks that may affect our business and that could cause our actual results to differ from those projected in these forward-looking statements, see the risk factors and uncertainties described under the heading “Risk Factors” in Part I, Item 1A of this Annual Report on Form 10-K. The forward-looking statements contained in this Annual Report on Form 10-K are expressly qualified in their entirety by this cautionary statement. We do not undertake any obligation to update any forward-looking statement to reflect events or circumstances after the date on which any such statement is made or to reflect the occurrence of unanticipated events, except as required by law.

Unless otherwise stated, references in this Annual Report on Form 10-K to “us,” “we,” “our,” or “Company” refer to Pulmatrix, Inc., a Delaware corporation, and its subsidiaries, Pulmatrix Operating Company, Inc. and PCL Merger Sub, Inc., both Delaware corporations, and PCL Merger Sub II, LLC, a Delaware limited liability company.

“iSPERSE^™” is one of our trademarks used in this Annual Report on Form 10-K. Other trademarks appearing in this report are the property of their respective holders. Solely for convenience, these and other trademarks, trade names and service marks referred to in this report appear without the ^®, TM and SM symbols, but those references are not intended to indicate, in any way, we or the owners of such trademarks will not assert, to the fullest extent under applicable law, their rights to these trademarks and trade names.

Overview

We are a biopharmaceutical company that has focused on the development of novel inhaled therapeutic products intended to prevent and treat migraine and respiratory diseases with important unmet medical needs using our patented iSPERSE^™ technology. Our proprietary product pipeline includes treatments for central nervous system (“CNS”) disorders such as acute migraine and serious lung diseases such as Chronic Obstructive Pulmonary Disease (“COPD”) and allergic bronchopulmonary aspergillosis (“ABPA”). Our product candidates are based on our proprietary engineered dry powder delivery platform, iSPERSE^™, which seeks to improve therapeutic delivery to the lungs by optimizing pharmacokinetics and reducing systemic side effects to improve patient outcomes.

We design and develop inhaled therapeutic products based on our proprietary dry powder delivery technology, iSPERSE^™, which enables delivery of small or large molecule drugs to the lungs by inhalation for local or systemic applications. The iSPERSE^™ powders are engineered to be small, dense particles with highly efficient dispersibility and delivery to airways. iSPERSE^™ powders can be used with an array of dry powder inhaler technologies and can be formulated with a broad range of drug substances including small molecules and biologics. We believe the iSPERSE^™ dry powder technology offers enhanced drug loading and delivery efficiency that outperforms traditional lactose-blend inhaled dry powder therapies.

We were incorporated in 2013 as a Delaware corporation.

After a comprehensive review of strategic alternatives, including identifying and reviewing potential candidates for a strategic transaction, on November 13, 2024, Pulmatrix entered into an Agreement and Plan of Merger and Reorganization (the “Merger Agreement”), by and among Pulmatrix, PCL Merger Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Pulmatrix (“Merger Sub I”), PCL Merger Sub II, LLC, a Delaware limited liability company and a wholly owned subsidiary of Pulmatrix (“Merger Sub II” and together with Merger Sub I, “Merger Subs”) and Cullgen Inc., a Delaware corporation (“Cullgen”), pursuant to which, and subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, among other things, Merger Sub I will merge with and into Cullgen, with Cullgen surviving the merger as the surviving corporation (the “First Merger” and the effective time of the First Merger, the “First Effective Time”) and as part of the same overall transaction, Cullgen will merge with and into Merger Sub II, with Merger Sub II continuing as a wholly owned subsidiary of Pulmatrix and the surviving corporation of the merger (the “Second Merger” and together with the First Merger, the “Merger”). The Merger Agreement was unanimously approved by the Pulmatrix board of directors, which resolved to recommend approval of the Merger Agreement to Pulmatrix stockholders.

The closing of the Merger (the “Closing”) is subject to approval by Pulmatrix stockholders and Cullgen stockholders, as well as other customary closing conditions, including the effectiveness of a registration statement filed with the SEC in connection with the transaction, Nasdaq’s approval of the listing of the shares of Pulmatrix common stock to be issued in connection with the Merger, and approval from the China Security Regulatory Commission. If the Merger is completed, the business of Cullgen will continue as the business of the combined company (the “Combined Company”). We are currently seeking opportunities to monetize our existing clinical assets.

The Company’s future operations are highly dependent on the success of the Merger and there can be no assurances that the Merger will be successfully consummated. There can be no assurance that the strategic review process or any transaction relating to a specific asset, including the Merger and any asset sale, will result in the Company pursuing such a transaction, or that any transactions, if pursued, will be completed on terms favorable to the Company and its stockholders in the existing Pulmatrix entity or any possible entity that results from a combination of entities. If the strategic review process is unsuccessful, and if the Merger is not consummated, the Pulmatrix board of directors may decide to pursue a dissolution and liquidation of the Company.

Business Strategy

Our goal has been to develop breakthrough therapeutic products that are safe, convenient, and more effective than the existing therapeutic products for respiratory and other diseases where iSPERSE^™ properties are advantageous.

Our current pipeline of clinical assets is aligned to this goal and includes iSPERSE^™-based therapeutic candidates which target the prevention and treatment of a range of diseases, including CNS disorders and pulmonary diseases. These therapeutic candidates include PUR3100 for the treatment of acute migraine, PUR1800 for the treatment of acute exacerbations of chronic obstructive pulmonary disease (“AECOPD”), and PUR1900 for the treatment of ABPA in patients with asthma and in patients with cystic fibrosis (“CF”). Each program is enabled by its unique iSPERSE^™ formulation designed to achieve specific therapeutic objectives.

We are exploring opportunities to monetize these clinical assets in connection with the Merger. Continued development of these candidates, if that were to occur, would be contingent on securing additional funding and would require significant expenditures to advance. Thereafter, if development of such product candidates were to be continued and successfully advanced (of which there can be no assurance), it would be necessary to seek and obtain marketing approval to commercialize such product candidates, which could be expected to require the expenditure of significant additional resources and expenses related to regulatory, product sales, medical affairs, marketing, manufacturing and distribution.

Contingent on securing additional funding and continuing development of these candidates, we would expect to continue to incur substantial expenses and operating losses for at least the next several years, as we would:

iSPERSE^™ Technology

We use simple, safe excipients, including proprietary cationic salt formulations, to create a robust and flexible dry powder platform technology that can accommodate a wide range of drug loads in highly dispersible particles. Our initial delivery platform emerged from development of iCALM^™ (inhaled Cationic Airway Lining Modulators), a non-steroidal anti-inflammatory therapy. The high degree of aerosol efficiency and the density profile of our dry powder iCALM^™ formulations provided the foundation for our development of iSPERSE^™ in 2012, which uses other monovalent and divalent salts.

iSPERSE^™ particles are engineered with a small, dense and dispersible profile to exceed the performance of traditional dry powder particles as the iSPERSE^™ particles have the dispersibility advantages of porous engineered particles. We believe this results in superior drug delivery compared to traditional oral and injectable forms of treatment for certain diseases. Unlike lactose-blended carrier formulations or low-density particles which disperse poorly, we believe that the iSPERSE^™ technology platform offers several potential benefits, achieved through the following technological innovations:

iSPERSE^™ particles can be engineered to include concentrations from less than one percent (1%) to greater than eighty percent (80%) active pharmaceutical ingredients (“APIs”), which allows flexibility for dosing both high potency and high-drug load therapeutics.

The iSPERSE^™ technology enables pulmonary delivery independent of lactose or other carriers, which results in significantly greater lung dose at a matched nominal dose of conventional lactose-based formulations. iSPERSE^™ formulations are dispersible across a range of flow rates with consistent emitted dose and particle size. Performance across flow rates provides reliable dose delivery across patient populations and reduces patient-to-patient variability.

iSPERSE^™ powders can be used with an array of dry powder inhaler technologies and can be formulated with a broad range of therapeutic compounds ranging from small molecules to proteins for both local and systemic drug delivery applications.

iSPERSE^™ creates homogenous particles including excipients and API, which allow for the consistent delivery of multiple APIs in a product. We have successfully formulated iSPERSE^™-based products with dual and triple API combinations.

Current iSPERSE^™ products and planned clinical-stage products to be formulated in iSPERSE^™ are supported by robust preclinical safety profiles. iSPERSE^™ excipients include those with inhalation precedent and those that are generally regarded as safe by other routes of administration.

Therapeutic Candidates

PUR3100

In 2020, we developed PUR3100, the iSPERSE^™ formulation of DHE, for the treatment of acute migraine. Currently DHE is only available as subcutaneous, intravenous infusion or intranasal delivery. If approved for commercialization, PUR3100 has the opportunity to be the first orally inhaled DHE treatment for acute migraine and be an alternative to other acute therapies. Given the oral inhaled route of delivery, PUR3100 is anticipated to provide relief from the rapid onset of migraine symptoms and provide a favorable tolerability profile.

Competition and Market Opportunities

The American Migraine Foundation estimates that at least 39 million people in the United States and 1 billion people worldwide live with migraine, but because many people are not diagnosed or do not receive the treatment they need, the actual number may be higher. Current treatments for migraine include oral, intranasal, IV or subcutaneous formulations of triptans, DHE, and calcitonin gene-related peptide (“CGRP”) antagonists (gepants). Studies show that people with migraines are underdiagnosed, undertreated, and experience substantial decreases in functioning and productivity, which translates into diminished quality of life for individuals, and financial burdens to patients, healthcare systems, and employers. All current treatments are limited by incomplete efficacy and/or intolerability. Therefore, development of additional treatments for acute migraine is warranted.

DHE has been shown to be effective in the treatment of migraine and, in particular, hard to treat migraines, such as menstrual migraine, migraine upon awakening, and severe migraine. Utilization of DHE has been limited due to its poor oral bioavailability, requiring IV, subcutaneous or intranasal dosing. IV dosing generally requires administration in a healthcare setting and may result in nausea and vomiting. Hence, its use has generally been limited to patients with intractable or medication-overuse migraine. Intranasal dosing with DHE, including Migranal (Bausch Health US LLC), approved in December 1997, and Trudhesa (Impel NeuroPharma, Inc.), approved by the FDA in September 2021, have been poorly adopted due to incomplete efficacy and intolerability of nasal inhalation in patients during a migraine.

There is precedent for an orally inhaled DHE therapy. MAP Pharmaceuticals, Inc. developed MAP0004, also known as Levadex or Semprana, a liquid suspension formulation of DHE, designed to be dosed via a pMDI inhalation device. Their published data indicate a safe and well tolerated formulation with rapid onset and long-lasting efficacy that compared favorably to existing treatments. Development of MAP0004 led to a new drug application (“NDA”) but was halted after multiple complete response letters from the FDA citing Chemistry, Manufacturing and Controls (“CMC”) issues related to dose uniformity and stability issues. Regardless of the failure of MAP0004, the efficacy and tolerability of the formulation reported by MAP Pharmaceuticals provides proof of concept for an orally inhaled DHE formulation. PUR3100, the iSPERSE^™ formulation planned by Pulmatrix, is anticipated to deliver DHE to the lung with efficacy and tolerability that compares favorably with MAP0004, while avoiding the device-related issues of MAP0004 by delivering PUR3100 as an iSPERSE^™ dry powder.

We believe that an iSPERSE formulation of DHE can provide the positive rapid onset and long-lasting efficacy seen in the MAP0004 data by enabling a similar pharmacokinetic profile while eliminating the manufacturing and device issues which led to the MAP0004 FDA complete response letters.

Vectura Inc. is developing an orally inhaled powder formulation of DHE for the acute treatment of migraines in adults. Vectura completed a Phase 1 clinical trial in 2024, with results pending. To the best of our knowledge, there are no other orally inhaled DHE formulations currently in development or on the market. Migranal and Trudhesa are the two currently FDA approved intranasal formulations of DHE. Satsuma Pharmaceuticals, a subsidiary of Shin Nippon Biomedical Laboratories (“Satsuma”), has developed a dry powder formulation of DHE for intranasal dosing and has completed two Phase 3 clinical studies (ClinicalTrials.gov: NCT03901482 and NCT04940390). Despite failure of both clinical studies to achieve primary endpoints, Satsuma filed an NDA in the first quarter of 2023 based on post-hoc analysis showing benefit in secondary endpoints. In January 2024, the FDA declined to approve the treatment, citing manufacturing concerns. Satsuma resubmitted its NDA in November 2024.

Non-Clinical Development

A total of three 14-day GLP toxicology studies have been completed with PUR3100 to support single-dose clinical studies. We are planning to conduct a chronic toxicology study to support long-term dosing. Based on discussions with the FDA, this would complete the non-clinical requirements to support an NDA.

Clinical Development

Our interactions with the FDA have indicated that, in addition to the planned Phase 2 and Phase 3 studies, long-term safety should be assessed in a minimum of one hundred patients for six months of dosing and fifty patients for twelve months of dosing. The FDA also confirmed that it will be necessary to perform a safety study administering PUR3100 to otherwise healthy patients with asthma before an NDA is submitted.

On September 26, 2022, we announced the completion of patient dosing in a Phase 1 clinical study, performed in Australia. The study design was a double-dummy, double-blinded trial to assess the safety, tolerability, and pharmacokinetics of three dose levels of single doses of inhaled PUR3100 with IV placebo, as compared to IV DHE (DHE mesylate injection) with inhaled placebo. This study may also provide preliminary comparative bioavailability data to support the use of the 505(b)(2) pathway for marketing authorization. Twenty-six healthy subjects were enrolled and each of the four groups contained at least six subjects.

On January 4, 2023, we announced topline results. We presented the Phase 1 study data at the American Headache Society 65th Annual Meeting in June 2023. The study showed that PUR3100 achieved peak exposures in the targeted therapeutic range and time to maximum concentration occurred at five minutes after dosing at all dosing levels. The PUR3100 dose groups also showed a lower incidence of nausea and no vomiting compared to observations of nausea and vomiting in the IV administered DHE dose group.

Based on the rapid systemic exposure in the therapeutic range and the improved side effect profile relative to IV dosing, we believe the PUR3100 formulation of DHE may differentiate from approved DHE products or those known to be in development. If effectiveness is demonstrated, PUR3100 may offer the convenience of being self-administered with a pharmacokinetic profile that may potentially provide rapid onset of action.

In September 2023, we announced that the FDA accepted the PUR3100 IND and the receipt of a “study may proceed” letter for the clinical study: “A Phase 2, Multicenter, Randomized, Double-Blind, Placebo-Controlled, Single Event Study to Evaluate the Safety, Tolerability, and Efficacy of PUR3100 (Dihydroergotamine Mesylate Inhalation Powder) in the Acute Treatment of Migraine”. We anticipate that this Phase 2 clinical study will initiate once financing or partnership arrangements have been made.

On May 15, 2024, we announced publication of, “Safety, tolerability, and pharmacokinetics of a single orally inhaled dose of PUR3100, a dry powder formulation of dihydroergotamine versus intravenous dihydroergotamine: A Phase 1 randomized, double-blind study in healthy adults” in the peer-reviewed publication Headache: The Journal of Head and Face Pain.

We believe that in this trial, PUR3100 demonstrated the potential for rapid pain relief and improved DHE tolerability versus IV DHE. With a T_max of 5 minutes and a C_max in the therapeutic window for all doses tested, we believe that PUR3100 has the potential to address an unmet need for acute migraine sufferers and we are pursuing different options to advance PUR3100 into a Phase 2 clinical trial to further investigate its promising profile in treating acute migraine.

The completed Phase 1 study demonstrated optimal pharmacokinetics and improved tolerability of PUR3100 compared to IV DHE. The Phase 1 trial was a randomized, double-dummy, double-blinded design to assesses the safety, tolerability, and pharmacokinetics (PK) of three dose groups treated with inhaled PUR3100 with intravenous (IV) placebo, compared to a single dose of IV DHE (DHE mesylate injection) with inhaled placebo in healthy volunteers. All doses of PUR3100 were generally well tolerated with a lower incidence of nausea (21% vs. 86%), vomiting (0% vs. 29%), and headache (16% vs. 57%) compared to IV DHE. The PK profile of PUR3100 versus IV DHE was characterized by a similar mean time to C_max (5 vs. 5.5 min), with reduced AUC0–2h (1120–4320 vs. 6340), and a lower C_max (3620–14,400 vs. 45,000). All doses of PUR3100 were associated with mean C_max above the minimum level required to achieve efficacy (1000 pg/mL).

PUR1800

Reduced responsiveness to corticosteroids represents an important barrier to effective treatment of COPD and AECOPD and provides a clear rationale to seek novel medicines to treat these respiratory diseases. In addition, current treatments generally fail to treat the underlying source of the AECOPD, in particular when a viral or bacterial infection is the cause, which occurs in approximately 80% of exacerbations. RV1162, the active ingredient of PUR1800, is a novel, potent anti-inflammatory that inhibits the phosphorylation of a narrow spectrum of kinases. In pre-clinical studies, RV1162 demonstrated direct anti-inflammatory activity in a model of viral induced respiratory inflammation. RV1162 also demonstrated a reduction in corticosteroid-resistant inflammatory responses in a model of cigarette smoke induced inflammation. These findings suggested that RV1162 has the potential to deliver effective anti-inflammatory outcomes in corticosteroid-resistant patients while also reducing the underlying source of inflammation in an exacerbation, such as a viral and/or bacterial respiratory infection.

Clinical studies conducted by RespiVert/Janssen with RV1162 formulated as a lactose blend for inhalation demonstrated that the molecule was well tolerated for up to 14 days of dosing in patients with COPD. Analysis of sputum collected from patients with COPD treated with RV1162 showed reduced levels of p38 phosphorylation in sputum cells and decreases in the number of neutrophils recovered in sputum after 12 days of dosing. These findings suggest that inhalation of RV1162 may confer anti-inflammatory benefits after a short dosing regimen. Long-term toxicology studies with RV1162 as a lactose blend suggested that this formulation was not suitable for chronic dosing.

Based upon the clinical results generated by RespiVert/Janssen for RV1162 and the anticipated benefits of an iSPERSE^™ formulation of RV1162, we entered into a License, Development and Commercialization Agreement with RespiVert Ltd. (“RespiVert”), a wholly owned subsidiary of Janssen Biotech, Inc. on June 9, 2017. RespiVert granted us an exclusive, royalty-bearing license in a portfolio of narrow spectrum kinase inhibitor compounds (“NSKI”). We subsequently formulated RV1162 into PUR1800 for development as a potential therapy for AECOPD.

Competition and Market Opportunities

There are 18 million moderate-to-severe episodes of AECOPD in the US each year. AECOPD are sudden onset increases in symptoms, including increased dyspnea, sputum purulence and volume, and wheezing, coughing, and shortness of breath that require medical intervention and can lead to hospitalization. The occurrence of an exacerbation greatly increases the likelihood of a further exacerbation within the following 6 months and creates a significant financial burden to healthcare systems.

Steroids are standard of care for moderate-to-severe acute exacerbations, which occur across all patient severity types. We believe a substantial unmet need exists in AECOPD for those patients with underlying infection and/or steroid resistance. Acumapimod (BCT-197) is an oral p38 MAP kinase inhibitor being developed by Mereo BioPharma. BCT-197 completed Phase 2 development as first-line therapy for severe AECOPD. In April 2019, Mereo BioPharma announced completion of an end of Phase 2 meeting with the FDA and stated the company is continuing discussions with potential partners for BCT-197. We are not aware of any further progress in either clinical development or partnership efforts on this product. A generic version of roflumilast, a phosphodiesterase inhibitor approved by the FDA for use in managing COPD exacerbations, became available in 2022.

Non-Clinical Development

We conducted two 28-day GLP toxicology studies in rats and dogs. Results from the two GLP toxicology studies supported the potential for PUR1800 to improve lung exposure, with reduced lung accumulation, as compared to RV1162 as a lactose blend formulation, suggesting potential for chronic dosing.

Toxicology studies in rats and dogs, with durations of six and nine months, respectively, were then completed. The data from both studies demonstrated that PUR1800 is safe and well tolerated with chronic dosing, with no progression of findings from 28-day studies. We believe this indicates potential for chronic dosing of PUR1800, within the safety margin identified, enabling us to explore PUR1800 therapy for chronic respiratory diseases such as steroid resistant asthma, COPD, or idiopathic pulmonary fibrosis. While the program is currently in development for treatment of AECOPD, these positive toxicology study results could expand potential indications and value of the program.

Clinical Development

We completed a Phase 1b safety, tolerability, and pharmacokinetics of PUR1800 for patients with stable moderate-severe COPD. Topline data was delivered in the first quarter of 2022 and presented at the American Academy of Allergy, Asthma and Immunology conference in the first quarter of 2023.

The clinical study, performed at the Medicines Evaluation Unit in Manchester, UK, was a randomized, three-way crossover double-blind study with 14 days of daily dosing, which included placebo and one of two doses of PUR1800, and included a 28-day follow-up period after each treatment period. A total of 18 adults with stable COPD were enrolled. Safety and tolerability, as well as systemic pharmacokinetics (“PK”) were evaluated.

PUR1800 was well tolerated and there were no observed safety signals. The PK data indicate that PUR1800 results in low and consistent systemic exposure when administered via oral inhalation. The topline data, along with the results from chronic toxicology studies, support the continued development of PUR1800 for the treatment of AECOPD and other inflammatory respiratory diseases. These data will inform the design of a potential Phase 2 study in the treatment of AECOPD.

PUR1900

PUR1900 is our iSPERSE^™ inhaled formulation of itraconazole, an antifungal drug commercially available as an oral drug. We developed PUR1900 for the prevention and treatment of fungal infections and allergic/hypersensitivity reactions to fungus in patients with severe lung disease, including those with asthma and CF. On January 28, 2020, PUR1900 received Fast Track designation from the FDA for the treatment of ABPA. Aspergillus colonization and infections are likely underdiagnosed and occur frequently in patients of all ages. Colonization and infection with Aspergillus can lead to clinical disease with differing severities and complications depending on the immune status of the host. Invasive aspergillosis is a frequently fatal disease that occurs in patients that are typically immune suppressed as a result of treatment for hematologic cancers or immunosuppression prior to solid organ transplantation. In patients with asthma and CF, Aspergillus can cause chronic infections that may be associated with worsening disease and larger declines in lung function than patients without infection. A subset of patients with asthma and CF with Aspergillus colonization and/or infection develop ABPA, which is a complex hypersensitivity reaction to fungal antigens. ABPA is a disease resulting in mucus production, wheezing, pulmonary infiltrates, worsening bronchiectasis, and fibrosis of the lung.

In patients with both asthma and CF, ABPA is commonly treated with oral steroids to treat inflammation and with oral antifungals to reduce fungal infection. The inhalation administration of a drug affords direct delivery of the drug to the infected parts of the lung, maximizing the dose to the affected sites and minimizing systemic exposure to the rest of the body where it could cause dose-limiting side effects. Therefore, treatment of lung infections by direct administration of anti-infective products to the lung may improve both the safety and efficacy of treatment compared to systemic administration by other routes, as well as improving patient convenience as compared to oral and injectable forms of the treatment. We believe that local lung delivery by inhalation of our iSPERSE^™ formulation could provide convenient, effective and safe management of the debilitating and often life-threatening lung infections that are not currently addressed by inhaled therapies.

Competition and Market Opportunities

Current treatments of pulmonary fungal infections highlight the limitations of oral or intravenous anti-infective treatments for lung infections. Itraconazole is one of the most commonly prescribed therapies for treating Aspergillus infections in patients with asthma and CF. Itraconazole is available commercially as Sporanox^® in both a capsule and oral solution form. Itraconazole is metabolized in the liver by CYP3A4 and coadministration with a large number of drugs is contraindicated due to the potential for severe drug-drug interactions.

We have demonstrated that PUR1900 achieves higher local lung itraconazole concentrations with lower systemic exposure relative to oral dosing, thus allowing for the potential to improve upon both the efficacy and safety profiles observed with oral itraconazole. Furthermore, administration by inhalation reduces the exposure of the drug in the rest of the body, which may be beneficial in reducing systemic side effects and the risk of potentially toxic drug-drug interactions.

There is precedent for both dry powder and nebulized inhaled anti-infective therapy to address specific pulmonary infections in patients which demonstrates potential utility of inhaled drug delivery and market opportunity. Mylan currently markets TOBI Podhaler for treatment of Pseudomonas aeruginosa infection in the United States and Teva markets inhaled colistin, Colobreathe, for the same infection in Europe. Insmed currently markets Amikacin Liposome Inhalation Suspension (Arikayce) in the United States for the treatment of lung disease caused by a group of bacteria, Mycobacterium avium complex in a limited population of patients with the disease who do not respond to conventional treatment (refractory disease). There are currently no products specifically approved for treatment of ABPA, however, there are several inhaled antifungal agents currently under development for the treatment of invasive aspergillosis or ABPA. Treatments under development for invasive aspergillosis include PC945, a novel azole antifungal being developed by Pulmocide as a liquid for nebulization, and a dry powder formulation of voriconazole being developed by TFF Pharmaceuticals. In principle, development of an orally inhaled antifungal for the treatment of invasive aspergillosis could also be effective for ABPA but would require additional clinical studies in the target patient population. Zambon has also developed a dry powder formulation of voriconazole for the treatment of ABPA and completed a Phase 1 study in the third quarter of 2020. However, no additional development has since been reported. Regeneron Pharmaceuticals is currently running a clinical trial with Dupilumab (NCT04442269) for the treatment of ABPA in asthma. This trial, which is focused on prevention of exacerbations in individuals with at least one or more severe respiratory exacerbations, completed in February 2024 and is pending results.

New methods to detect Aspergillus infection in sputum have improved the sensitivity of diagnosis and clinical appreciation for these infections. Pulmonary Aspergillus infections affect approximately 14 million patients worldwide according to the Global Action Fund for Fungal Infections (Improving Outcomes for Patients with Fungal Infections across the World: A Road Map for the Next Decade). The majority of these cases occur in patients with asthma who have allergic disease and also include invasive Aspergillus infections that are associated with a high rate of mortality in immunocompromised patients. We believe that PUR1900 compares favorably to the products discussed above and has the potential to generate substantial value based on treating and preventing pulmonary fungal infections in multiple patient populations.

Clinical Development

We completed a Phase 1/1b clinical study in 2018, wherein PUR1900 appeared to be safe and well tolerated in healthy normal volunteers (Parts 1 and 2) and in patients with asthma (Part 3). In Part 3 of the Phase 1/1b clinical study, following a single dose of PUR1900, the pharmacokinetics (“PK”) analysis of sputum samples demonstrated approximately 70-fold higher maximum lung concentration of itraconazole following inhalation of PUR1900 compared to oral Sporanox^® (Janssen Pharmaceuticals) despite inhaling only one-tenth the dose of itraconazole (20 mg) relative to the dose of oral Sporanox^® (200 mg). Lung exposure, as measured by sputum induction and analysis, was approximately 50-fold higher and plasma exposure was approximately 85-fold lower following inhalation of 20 mg of PUR1900 compared to 200 mg of oral Sporanox^®. All endpoints from the Phase 1/1b clinical study were successfully met.

Successful completion of the Phase 1/1b clinical study enabled us to initiate a Phase 2 clinical study in 2019, entitled: “A Randomized, Double-Blind, Multicenter, Placebo-Controlled, Phase 2 Study to Evaluate the Safety, Tolerability, and Pharmacokinetics of Itraconazole Administered as a Dry Powder for Inhalation (PUR1900) in Adult Asthmatic Patients with ABPA.” This clinical study was terminated in July 2020 due to the impact of the COVID-19 pandemic on patient enrollment and clinical study conduct. The completion of a 6-month inhalation toxicology study in dogs in 2020 enabled the conduct of a new Phase 2b clinical study.

The new Phase 2b study included a 16-week dosing regimen and exploration of potential regulatory approval endpoints. We dosed the first patient during the first quarter of 2023. In January 2024, pursuant to the Third Amendment (as defined herein), we announced plans to stop patient enrollment at 8 subjects in this study, effective immediately, and to terminate the study as soon as reasonably possible between the date of the Third Amendment and July 30, 2024. We completed all Phase 2b wind down activities in the third quarter of 2024. As such, we no longer bear further financial responsibility for the commercialization and development with respect to the Product in the Cipla Territory, with such commercialization and development expenses of the Product in the Cipla Territory to be borne at Cipla’s sole cost and expense after January 6, 2024.

Our partner Cipla has continued clinical development outside the United States and has advised us that they have completed their Phase 2 study in India. Should Cipla successfully market PUR1900 outside the United States, Pulmatrix will receive 2% royalties on any potential future net sales by Cipla outside the United States. Within the United States, we and Cipla will seek to monetize PUR1900 for indications where an orally inhaled antifungal may provide a therapeutic benefit or fulfill an unmet medical need.

Business Development

PUR3100

We are currently exploring opportunities to monetize PUR3100.

In September 2023, we announced the FDA’s acceptance of an IND application for PUR3100 and receipt of a “study may proceed” letter for a Phase 2 study. The IND includes a Phase 2 clinical protocol where safety and preliminary efficacy of PUR3100 will be investigated in patients with acute migraine.

PUR1800

We are currently exploring opportunities to monetize PUR1800.

We completed a Phase 1b safety, tolerability, and pharmacokinetics clinical study of PUR1800 for subjects with stable moderate-severe COPD and received topline data from the Phase 1b clinical study in the first quarter of 2022. We analyzed data from the completed Phase 1b clinical study of PUR1800 for AECOPD and presented study results at the American Academy of Allergy, Asthma & Immunology (AAAAI) conference in the first quarter of 2023. The results indicated PUR1800 was safe and well tolerated with no observed safety signals. The topline data, along with the results from chronic toxicology studies, support the continued development of PUR1800 for the treatment of AECOPD and other inflammatory respiratory diseases.

PUR1900

We are currently exploring opportunities to monetize PUR1900 within the United States.

On April 15, 2019, we entered into a Development and Commercialization Agreement (the “Cipla Agreement”) with Cipla for the co-development and commercialization, on a worldwide, except for the Cipla Territory defined below, exclusive basis, of PUR1900, our inhaled iSPERSE^™ drug delivery system (the “Product”) enabled formulation of the antifungal drug itraconazole, which is only available as an oral drug, for the treatment of all pulmonary indications, including ABPA in patients with asthma. We entered into an amendment to the Cipla Agreement on November 8, 2021 (the “Second Amendment”) and a subsequent amendment on January 6, 2024 (the “Third Amendment”). All references to the Cipla Agreement herein refer to the Cipla Agreement, as amended. The Cipla Agreement will remain in effect in perpetuity, unless otherwise earlier terminated in accordance with its terms.

Pursuant to the Third Amendment, all development and commercialization activities with respect to the Product in all markets other than the United States (the “Cipla Territory”) will be conducted exclusively by Cipla at Cipla’s sole cost and expense, and Cipla shall be entitled to all profits from the sale of the Product in the Cipla Territory, except that we will receive 2% royalties on any potential future net sales by Cipla outside the United States.

Also pursuant to the Third Amendment, we and Cipla stopped patient enrollment for the ongoing Phase 2b clinical study. We agreed that during the period commencing on January 6, 2024 and ending July 30, 2024 (the “Wind Down Period”), we would complete all Phase 2b activities, assign or license all patents to Cipla and their registration with the appropriate authorities in the Cipla Territory, complete a physical and demonstrable technology transfer and secure all data from the Phase 2b study for inclusion in the safety database for the Cipla Territory.

For the duration of the Wind Down Period, we and Cipla were each responsible for 60% and 40%, respectively, of our Direct Costs. We shared all other development costs with Cipla that are not Direct Costs, such as the cost of clinical research organizations, manufacturing costs and other third-party costs, on a 50/50 basis. Reimbursements from Cipla to us for these costs were subject to a maximum reimbursement amount as approved by the joint steering committee.

We completed all Phase 2b wind down activities in the third quarter of 2024. As such, we no longer bear further financial responsibility for the commercialization and development with respect to the Product in the Cipla Territory, with such commercialization and development expenses of the Product in the Cipla Territory to be borne at Cipla’s sole cost and expense after January 6, 2024. We will receive 2% royalties on any potential future net sales by Cipla outside the United States. Within the United States, we and Cipla will seek to monetize PUR1900, our inhaled iSPERSE^™ formulation of the antifungal drug itraconazole for indications where an orally inhaled antifungal may provide a therapeutic benefit or fulfill an unmet medical need.

Intellectual Property

Patents and Patent Applications

We protect our intellectual property by filing and advancing patent applications and maintaining granted patents on our iSPERSE^™ platform technology and in-licensed kinase inhibitors, which includes claims to compositions of matter and methods of use for our PUR3100, PUR1800, PUR1900 and other programs, as well as manufacturing processes, devices and packaging relevant to our iSPERSE^™ platform and product candidates.

The status of our patent portfolio changes frequently in the ordinary course of patent prosecution. As of December 31, 2024, our patent portfolio related to iSPERSE™ included approximately 149 granted patents, 19 of which are granted US patents, with expiration dates from 2024 to 2037, and approximately 50 additional pending patent applications in the US and other jurisdictions. Our in-licensed portfolio related to kinase inhibitors included approximately 281 granted patents, 33 of which are granted US patents, with expiration dates from 2029 to 2035, and approximately 17 additional pending patent applications in the US and other jurisdictions. We have national phase applications pending in Australia, Brazil, Canada, China, Europe, Israel, India, Japan, Korea, Mexico, New Zealand, Russia, and the United States that cover certain formulations and methods of use relevant to our PUR3100 program.

There can be no assurance that the patent applications will be granted. The term of individual patents depends upon the legal term of the patents in the countries in which they are obtained. In most countries in which we file, the patent term is 20 years from the earliest date of filing a non-provisional patent application. In the United States, the patent term of a patent that covers a FDA-approved drug may also be eligible for patent term extension, which permits patent term restoration as compensation for the patent term lost during the FDA regulatory review process. The length of the patent term extension is related to the length of time the drug is under regulatory review. Patent term extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval and only one patent applicable to an approved drug may be extended. In the future, if and when our products receive FDA approval, we expect to apply for patent term extensions on patents covering those products. Similar provisions are available in Europe and other foreign jurisdictions to extend the term of a patent that covers an approved drug. We plan to seek patent term extensions to extend the patent coverage of any of our products that received regulatory approval in any jurisdiction where these extensions are available. However, there is no guarantee that the applicable authorities, including the FDA in the United States, will agree with our assessment on whether such extensions should be granted, and if granted, the length of such extensions.

The patent positions of biotechnology companies like ours are generally uncertain and involve complex legal, scientific and factual questions. In addition, the coverage claimed in a patent application can be significantly reduced before the patent is issued, and its scope can be reinterpreted after issuance. Consequently, we may not obtain or maintain adequate patent protection for any of our product candidates. We cannot predict whether the patent applications we are currently pursuing will issue as patents in any particular jurisdiction or whether the claims of any issued patents will provide sufficient proprietary protection from competitors. Any patents that we hold may be challenged, circumvented or invalidated by third parties.

Trade Secrets

We also rely on trade secret protection of our confidential and proprietary information, including the iSPERSE^™ technology. Although we take steps to protect our proprietary information and trade secrets, including through contractual means with our employees, consultants and others, third parties may independently develop substantially equivalent proprietary information and techniques or otherwise gain access to our trade secrets or disclose our technology. Thus, we may not be able to meaningfully protect our trade secrets. It is our policy to require our employees, consultants, outside scientific collaborators, sponsored researchers and other advisors to execute confidentiality agreements upon the commencement of employment or consulting relationships with us. These confidentiality agreements provide that all confidential information concerning our business or financial affairs developed or made known to the individual during the course of the individual’s relationship with us must be kept confidential and not disclosed to third parties except in specific circumstances. Our confidentiality agreements with our employees also provide that all inventions conceived by the employee in the course of employment with us or from the employee’s use of our confidential information are our exclusive property.

Manufacturing

We do not currently own or operate manufacturing facilities for the production of clinical or commercial quantities of our product candidates. We have historically maintained small-scale production capabilities and performed early process development for our product candidates to produce the quantities necessary to conduct preclinical studies of our investigational product candidates. We do not have, and do not currently plan to acquire or develop, the facilities or capabilities to manufacture bulk drug substance or drug product for use in human clinical studies. We rely on contract manufacturing organizations (“CMOs”) and third-party contractors to manufacture drug substance and drug product required for our clinical studies. We expect to continue to rely on CMOs to manufacture drug substances and drug products under the appropriate current Good Manufacturing Practices (“cGMP”) conditions to perform clinical studies for the foreseeable future. We also contract with CMOs for the labeling, packaging, storage and distribution of investigational drug products. These arrangements allow us to maintain a more flexible infrastructure while focusing our expertise on researching and developing our products.

We expect to continue to rely on contract manufacturers to produce sufficient quantities of our product candidates in accordance with the appropriate cGMPs for the pertinent phase of clinical trials. cGMP compliance includes strict adherence to regulations for quality control, quality assurance, and the maintenance of records and documentation. The manufacturing facilities that manufacture our approved drug products, if any are approved in the future, must comply with the FDA’s cGMP regulation requirements and have acquired FDA or other regulatory approval for the manufacturing of our commercial products. Our contract manufacturers may also be subject to inspections of facilities by regulatory authorities to ensure compliance with applicable regulations. Contract manufacturers often encounter difficulties involving production yields, quality control and quality assurance, as well as shortages of qualified personnel. We have little or no direct control over our manufacturers’ compliance with these regulations and standards. Failure to comply with applicable regulatory requirements may result in fines and civil penalties, suspension of production, suspension or delay in product approval, product seizure or recall, or withdrawal of product approval. These actions could have a material impact on the availability of products.

Suppliers

We also rely on third-party contract manufacturers to supply the APIs that are used to formulate our therapeutic candidates. We place purchase orders with different contract manufacturers for the APIs required for PUR3100, PUR1800 and PUR1900. We additionally rely on third-party vendors to supply raw materials for our APIs and drug products.

Research and Development

For fiscal years ended December 31, 2024 and 2023, we spent approximately $7.2 million and $15.5 million, respectively, on research and development activities.

Government Regulation

Pharmaceutical companies are subject to extensive regulation by national, state and local agencies, such as the FDA, in the United States and the European Medicines Agency in Europe. The manufacture, distribution, marketing, and sale of pharmaceutical products are subject to government regulation in the United States and various foreign countries. Additionally, in the United States, we must follow rules and regulations established by the FDA requiring the presentation of data indicating that our products are safe and efficacious and are manufactured in accordance with cGMP regulations. If we do not comply with applicable requirements, we may be fined, the government may refuse to approve our marketing applications or allow us to manufacture or market its products, and we may be criminally prosecuted. We and our manufacturers and clinical research organizations may also be subject to regulations under other federal, state and local laws, including, but not limited to, the U.S. Occupational Safety and Health Act, the Resource Conservation and Recovery Act, the Clean Air Act and import, export and customs regulations as well as the laws and regulations of other countries. Pharmaceutical companies must ensure their compliance with the Foreign Corrupt Practices Act and federal healthcare fraud and abuse laws, including the False Claims Act, and the U.S. government has increased its enforcement activity regarding illegal marketing practices domestically and internationally.

These regulatory requirements impact our operations and differ from one country to another, such that securing the applicable regulatory approvals of one country does not imply the approval of another country. However, securing the approval of a more stringent body, e.g., the FDA, may facilitate receiving the approval by a regulatory authority in a different country where the regulatory requirements are similar or less stringent. The approval procedures involve high costs and are manpower intensive and usually extend over many years and require highly skilled and professional resources.

FDA Approval Process

The steps required to be taken before a new drug may be marketed in the United States generally include:

Clinical studies are conducted under protocols detailing, among other things, the objectives of the study, what types of patients may enter the study, schedules of tests and procedures, drugs, dosages, and length of study, as well as the parameters to be used in monitoring safety, and the efficacy criteria to be evaluated. A protocol for each clinical study and any subsequent protocol amendments must be submitted to the FDA as part of the IND application and, subsequently adhered to in conducting clinical trials, if the IND application is accepted.

In all the countries that are signatories of the Helsinki Declaration, the prerequisite for conducting clinical trials on human subjects is securing the preliminary approval of the competent authorities of that country to conduct medical experiments on human subjects in compliance with the other principles established by the Helsinki Declaration.

The clinical testing of a product candidate (also commonly referenced as a “drug product candidate” or a “therapeutic product candidate”) generally is conducted in three sequential phases prior to approval, but the phases may overlap or be combined. A fourth, or post approval, phase may include additional clinical studies. The phases are generally as follows:

Phase 1. In Phase 1 clinical studies, the product is tested in a small number of patients with the target condition or disease or in healthy volunteers. These studies are designed to evaluate the safety, dosage tolerance, metabolism and pharmacologic actions of the product candidate in humans, side effects associated with increasing doses, and, in some cases, to gain early evidence on efficacy. The number of participants included in Phase 1 studies is generally in the range of 20 to 80.

Phase 2. In Phase 2 studies, in addition to safety, the sponsor evaluates the efficacy of the product candidate on targeted indications to determine dosage tolerance and optimal dosage and to identify possible adverse effects and safety risks. Phase 2 studies typically are larger than Phase 1 but smaller than Phase 3 studies and may involve several hundred participants.

Phase 3. Phase 3 studies typically involve an expanded patient population at geographically-dispersed test sites. They are performed after preliminary evidence suggesting effectiveness of the product candidate has been obtained and are designed to further evaluate clinical efficacy and safety, to establish the overall benefit-risk relationship of the product candidate and to provide an adequate basis for a potential product approval. Phase 3 studies usually involve several hundred to several thousand participants.

Phase 4. Phase 4 clinical trials are post marketing studies designed to collect additional safety data as well as potentially expand a product indication. Post marketing commitments are required of, or agreed to by, a sponsor after the FDA has approved a product for marketing. These studies are used to gain additional information from the treatment of patients in the intended therapeutic indication and to verify a clinical benefit in the case of drugs approved under accelerated approval regulations. If the FDA approves a product while a company has ongoing clinical trials that were not necessary for approval, a company may be able to use the data from these clinical trials to meet all or part of any Phase 4 clinical trial requirement. These clinical trials are often referred to as Phase 4 post-approval or post marketing commitments. Failure to promptly conduct Phase 4 clinical trials could result in the inability to deliver the product into interstate commerce, misbranding charges, and civil monetary penalties.

Clinical trials must be conducted in accordance with the FDA’s good clinical practices (“GCP”), requirements. The FDA may order the temporary or permanent discontinuation of a clinical study at any time or impose other sanctions if it believes that the clinical study is not being conducted in accordance with FDA requirements or that the participants are being exposed to an unacceptable health risk. In addition, to support an IND or an application for marketing approval with the FDA, clinical studies conducted outside of the United States must conform with GCP requirements. An institutional review board (“IRB”) generally must approve the clinical trial design and patient informed consent at study sites that the IRB oversees and also may halt a study, either temporarily or permanently, for failure to comply with the IRB’s requirements, or may impose other conditions. Additionally, some clinical studies are overseen by an independent group of qualified experts organized by the clinical study sponsor, known as a data safety monitoring board or committee. This group recommends whether or not a trial may move forward at designated check points based on access to certain data from the study. The clinical study sponsor may also suspend or terminate a clinical trial based on evolving business objectives and/or competitive climate.

As a product candidate moves through the clinical testing phases, manufacturing processes are further defined, refined, controlled and validated. The level of control and validation required by the FDA would generally increase as clinical studies progress. We and the third-party manufacturers on which we rely for the manufacture of our product candidates and their respective components (including the API) are subject to requirements that drugs be manufactured, packaged and labeled in conformity with cGMP. To comply with cGMP requirements, manufacturers must continue to spend time, money and effort to meet requirements relating to personnel, facilities, equipment, production and process, labeling and packaging, quality control, recordkeeping and other requirements.

Assuming completion of all required testing in accordance with all applicable regulatory requirements, detailed information on the product candidate is submitted to the FDA in the form of an NDA, requesting approval to market the product for one or more indications, together with payment of a user fee, unless waived. An NDA includes all relevant data available from pertinent nonclinical and clinical studies, including negative or ambiguous results as well as positive findings, together with detailed information on the chemistry, manufacture, control and proposed labeling, among other things. To support marketing approval, the data submitted must be sufficient in quality and quantity to establish the safety and efficacy of the product candidate for its intended use to the satisfaction of the FDA.

If an NDA submission is accepted for filing, the FDA begins an in-depth review of the NDA. Under the Prescription Drug User Fee Act (the “PDUFA”), the FDA’s goal is to complete its initial review and respond to the applicant within twelve months of submission, unless the application relates to an unmet medical need in a serious or life-threatening indication, in which case the goal may be within eight months of NDA submission. However, PDUFA goal dates are not legal mandates and FDA response often occurs several months beyond the original PDUFA goal date. Further, the review process and the target response date under PDUFA may be extended if the FDA requests or the NDA sponsor otherwise provides additional information or clarification regarding information already provided in the NDA. The NDA review process can, accordingly, be very lengthy. During its review of an NDA, the FDA may refer the application to an advisory committee for review, evaluation and recommendation as to whether the application should be approved. The FDA is not bound by the recommendation of an advisory committee, but it typically follows such recommendations. Data from clinical studies are not always conclusive and the FDA and/or any advisory committee it appoints may interpret data differently than the applicant.

After the FDA evaluates the NDA and inspects manufacturing facilities where the drug product and/or its API will be produced, it will either approve commercial marketing of the drug product with prescribing information for specific indications or issue a complete response letter indicating that the application is not ready for approval and stating the conditions that must be met in order to secure approval of the NDA. If the complete response letter requires additional data and the applicant subsequently submits that data, the FDA nevertheless may ultimately decide that the NDA does not satisfy its criteria for approval. The FDA could also approve the NDA with a Risk Evaluation and Mitigation Strategies, plan to mitigate risks, which could include medication guides, physician communication plans, or elements to assure safe use, such as restricted distribution methods, patient registries and other risk minimization tools. The FDA also may condition approval on, among other things, changes to proposed labeling, development of adequate controls and specifications, or a commitment to conduct post-marketing testing. Such post-marketing testing may include Phase 4 clinical studies and surveillance to further assess and monitor the product’s safety and efficacy after approval. Regulatory approval of products for serious or life-threatening indications may require that participants in clinical studies be followed for long periods to determine the overall survival benefit of the drug.

If the FDA approves one of our therapeutic candidates, we will be required to comply with a number of post-approval regulatory requirements. We will also be required to report, among other things, certain adverse reactions and production problems to the FDA, provide updated safety and efficacy information and comply with requirements concerning advertising and promotional labeling for any of its products. Also, quality control and manufacturing procedures must continue to conform to cGMP after approval, and the FDA periodically inspects manufacturing facilities to assess compliance with cGMP, which imposes extensive procedural, substantive and record keeping requirements. If we seek to make certain changes to an approved product, such as certain manufacturing changes, we will need FDA review and approval before the change can be implemented. For example, if we change the manufacturer of a product or its API, the FDA may require stability or other data from the new manufacturer, which will take time and is costly to generate, and the delay associated with generating this data may cause interruptions in its ability to meet commercial demand, if any. While physicians may use products for indications that have not been approved by the FDA, we may not label or promote the product for an indication that has not been approved. Securing FDA approval for new indications is similar to the process for approval of the original indication and requires, among other things, submitting data from adequate and well-controlled studies that demonstrate the product’s safety and efficacy in the new indication. Even if such studies are conducted, the FDA may not approve any change in a timely fashion, or at all.

We rely, and expect to continue to rely, on third parties for the manufacture of clinical and future commercial, quantities of its therapeutic candidates. Future FDA and state inspections may identify compliance issues at these third-party facilities that may disrupt production or distribution or require substantial resources to correct. In addition, discovery of previously unknown problems with a product or the failure to comply with applicable requirements may result in restrictions on a product, manufacturer or holder of an approved NDA, including withdrawal or recall of the product from the market or other voluntary, FDA-initiated or judicial action that could delay or prohibit further marketing. Newly discovered or developed safety or efficacy data may require changes to a product’s approved labeling, including the addition of new warnings and contraindications, and also may require the implementation of other risk management measures. Many of the foregoing could limit the commercial value of an approved product or require us to commit substantial additional resources in connection with the approval of a product. Also, new government requirements, including those resulting from new legislation, may be established, or the FDA’s policies may change, which could delay or prevent regulatory approval of its products under development.

Section 505(b)(2) New Drug Applications

As an alternate path for FDA approval of new indications or new formulations of previously approved products, a company may file a Section 505(b)(2) NDA, instead of a “stand-alone” or “full” NDA. Section 505(b)(2), was enacted as part of the Drug Price Competition and Patent Term Restoration Act of 1984, otherwise known as the Hatch-Waxman Amendments. Section 505(b)(2) permits the submission of an NDA where at least some of the information required for approval comes from studies not conducted by or for the applicant and for which the applicant has not obtained a right of reference. Some examples of products that may be allowed to follow a 505(b)(2) path to approval are drugs that have a new dosage form, strength, route of administration, formulation or indication.

The Hatch-Waxman Amendments permit the applicant to rely upon certain published nonclinical or clinical studies conducted for an approved product or the FDA’s conclusions from prior review of such studies. The FDA may require companies to perform additional studies or measurements to support any changes from the approved product. The FDA may then approve the new product for all or some of the labeled indications for which the reference product has been approved, as well as for any new indication supported by the NDA. While references to nonclinical and clinical data not generated by the applicant or for which the applicant does not have a right of reference are allowed, all development, process, stability, qualification and validation data related to the manufacturing and quality of the new product must be included in an NDA submitted under Section 505(b)(2).

To the extent that the Section 505(b)(2) applicant is relying on the FDA’s conclusions regarding studies conducted for an already approved product, the applicant is required to certify to the FDA concerning any patents listed for the approved product in the FDA’s Orange Book publication. Specifically, the applicant must certify that: (i) the required patent information has not been filed; (ii) the listed patent has expired; (iii) the listed patent has not expired but will expire on a particular date and approval is sought after patent expiration; or (iv) the listed patent is invalid or will not be infringed by the new product. The Section 505(b)(2) application also will not be approved until any non-patent exclusivity, such as exclusivity for obtaining approval of a new chemical entity, listed in the Orange Book for the reference product has expired. Thus, the Section 505(b)(2) applicant may invest a significant amount of time and expense in the development of its products only to be subject to significant delay and patent litigation before its products may be commercialized.

Orphan Drug Designation

The Orphan Drug Act of 1983 (the “Orphan Drug Act”) encourages manufacturers to seek approval of products intended to treat “rare diseases and conditions” with a prevalence of fewer than 200,000 patients in the United States or for which there is no reasonable expectation of recovering the development costs for the product. For products that receive Orphan Drug designation by the FDA, the Orphan Drug Act provides tax credits for clinical research, FDA assistance with protocol design, eligibility for FDA grants to fund clinical studies, waiver of the FDA application fee, and a period of seven years of marketing exclusivity for the product following FDA marketing approval. In limited circumstances, the FDA may approve a competing product if the product shows clinical superiority over a product with orphan drug designation exclusivity.

Foreign Regulation

In addition to regulations in the United States, we will be subject to a variety of foreign regulations governing clinical trials and commercial sales and distribution of its products. Whether or not we obtain FDA approval for a product, we must obtain approval by the comparable regulatory authorities of foreign countries before we can commence clinical trials or marketing of the product in those countries. The approval process varies from country to country and the time may be longer or shorter than that required for FDA approval. The requirements governing the conduct of clinical trials, product licensing, pricing and reimbursement vary greatly from country to country.

Under European Union regulatory systems, a company may submit marketing authorization applications either under a centralized or decentralized procedure. The centralized procedure, which is compulsory for medicines produced by biotechnology or those medicines intended to treat acquired immunodeficiency syndrome, cancer, neurodegenerative disorders or diabetes and optional for those medicines which are highly innovative, provides for the grant of a single marketing authorization that is valid for all European Union member states. Abridged applications for the authorization of generic versions of drugs authorized by European Medicines Agency can be submitted to the European Medicines Agency through a centralized procedure referencing the innovator’s data and demonstrating bioequivalence to the reference product, among other things. The decentralized procedure provides for mutual recognition of national approval decisions. Under this procedure, the holder of a national marketing authorization may submit an application to the remaining member states. Within 90 days of receiving the applications and assessments report, each member state must decide whether to recognize approval. If a member state does not recognize the marketing authorization, the disputed points are eventually referred to the European Commission, whose decision is binding on all member states.

Reimbursement

In the United States and other countries, sales of any products for which we receive regulatory approval for commercial sale will depend in part on the availability of reimbursement from third-party payors, including government payors, managed care providers, private health insurers and other organizations. Each third-party payor may have its own policy regarding what products it will cover, the conditions under which it will cover such products, and how much it will pay for such products. Third-party payors are increasingly examining the medical necessity and cost effectiveness of medical products and services in addition to safety and efficacy and, accordingly, significant uncertainty exists as to the reimbursement status of newly approved therapeutics. Without adequate coverage and reimbursement from third-party payors, patients and providers are unlikely to use or prescribe any products for which we receive regulatory approval for commercial sale and may not enable us to realize an appropriate return on our investment in research and product development may not be available for our products.

The passage of the Medicare Prescription Drug, Improvement and Modernization Act of 2003 (the “MMA”) sets forth requirements for the distribution and pricing of prescription drugs for Medicare beneficiaries, which may affect the marketing of our products. The MMA also introduced a new reimbursement methodology. Moreover, while the MMA applies only to drug benefits for Medicare beneficiaries, private payors often follow Medicare coverage policy and payment limitations in setting their own payment rates. Any reduction in payment that results from the MMA may result in a similar reduction in payments from non-governmental payors.

More recently, the Inflation Reduction Act of 2022 requires, among other things, the Secretary of the U.S. Department of Health and Human Services to negotiate the price of a set number of high Medicare spend drugs starting in 2026, requires rebates from manufacturers who increase their drug prices above inflation, and makes several changes to the Medicare Part D benefit that will increase manufacturer liability for drug costs previously borne by the government and beneficiaries under the program.

In addition, in some foreign countries, the proposed pricing for a drug must be approved before it may be lawfully marketed. The requirements governing drug pricing vary widely from country to country. For example, the European Union provides options for its member states to restrict the range of medicinal products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use. A member state may approve a specific price for the medicinal product, or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the medicinal product on the market.

We expect that there will continue to be a number of federal and state proposals to implement governmental pricing controls. While we cannot predict whether such legislative or regulatory proposals will be adopted, the adoption of such proposals could have a material adverse effect on our business, financial condition and profitability.

Compliance with Environmental Laws

Compliance with applicable environmental requirements during the years ended December 31, 2024 and 2023 has not had a material effect upon our capital expenditures, earnings or competitive position.

Employees

As of December 31, 2024, we had two full-time employees, both of whom were engaged in full-time administrative activities. None of our employees are represented by any collective bargaining unit. We believe that we maintain good relations with our employees.

Properties

We are a virtual company and do not lease or own any physical space. We maintain a mailing address at 945 Concord Street, Suite 1217, Framingham, Massachusetts 01701.

We assigned our previous lease, for our previous headquarters in Bedford, Massachusetts, during the third quarter of 2024 to MannKind Corporation.

Available Information

We are subject to the information and periodic reporting requirements of the Securities Exchange Act of 1934, as amended, and, in accordance therewith, we file periodic reports, proxy statements and other information with the Securities and Exchange Commission. We make available, free of charge, our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to these reports on our website at www.pulmatrix.com as soon as reasonably practicable after those reports and other information is electronically filed with, or furnished to, the Securities and Exchange Commission.

The following risk factors, together with all of the other information included or incorporated in this Annual Report on Form 10-K, should be carefully considered. If any of the following risks, either alone or taken together, or other risks not presently known to us or that we currently believe to not be significant, develop into actual events, then our business, financial condition, results of operations or prospects could be materially adversely affected. If that happens, the market price of our common stock could decline, and stockholders may lose all or part of their investment.

Risk Factor Summary

We are providing the following summary of the risk factors contained in this Annual Report on Form 10-K to enhance the readability and accessibility of our risk factor disclosures. We encourage you to carefully review the full risk factors contained in this Annual Report on Form 10-K in their entirety for additional information regarding the material factors that make an investment in our securities speculative or risky. These risks and uncertainties include, but are not limited to, the following:

Risks Related to the Merger with Cullgen

Risks Related to the Proposed Reverse Stock Split

Risks Related to Our Business

Risks Related to Regulatory Matters

Risks Related to Our Financial Position and Need for Additional Capital

Risks Related to Our Intellectual Property

Risks Related to Our Common Stock

Risks Related to the Merger with Cullgen

There is no assurance when or if the Merger will be completed. Any delay in completing the Merger may substantially reduce the potential benefits that we and Cullgen expect to obtain from the Merger.

Completion of the Merger is subject to the satisfaction or waiver of a number of conditions, as set forth in the Merger Agreement, including the approval by our stockholders, approval by Nasdaq of our application for the initial listing of our common stock to be issued in connection with the Merger, and other customary closing conditions. There can be no assurance that we and Cullgen will be able to satisfy the closing conditions or that closing conditions beyond their control will be satisfied or waived. For a discussion of the conditions to the completion of the Merger, see the section titled “The Merger Agreement-Conditions to the Completion of the Merger” beginning on page 147 of the proxy statement/prospectus included in the registration statement on Form S-4, filed with the SEC on February 14, 2025 (the “proxy statement/prospectus”). If the conditions are not satisfied or waived, the Merger may not occur or may not be completed within the expected timeframe, and we and Cullgen each may materially and adversely lose some or all of the potential benefits that we and Cullgen expect to achieve as a result of the Merger and could result in additional transaction costs or other effects associated with uncertainty about the Merger. In addition, pursuant to the Merger Agreement, we may extend the originally scheduled End Date (defined in the Merger Agreement as August 13, 2025) by up to 60 calendar days (to October 12, 2025). Moreover, each of we and Cullgen has incurred and expects to continue to incur significant expenses related to the Merger, such as legal and accounting fees, some of which must be paid even if the Merger is not completed.

We and Cullgen can agree at any time to terminate the Merger Agreement, even if our stockholders and/or Cullgen securityholders have already adopted the Merger Agreement and thereby approved the Merger and the other transactions contemplated by the Merger Agreement. We and Cullgen can also terminate the Merger Agreement under other specified circumstances.

In addition, if the Merger Agreement is terminated and our board of directors or the Cullgen board of directors determines to seek another business combination, it may not be able to find a third party willing to provide equivalent or more attractive consideration than the consideration to be provided by each party in the Merger. In such circumstances, our board of directors may elect to, among other things, divest all or a portion of our business, or take the steps necessary to liquidate all of our business and assets, and in either such case, the consideration that we receive may be less attractive than the consideration to be received by us pursuant to the Merger Agreement.

If the Merger Agreement is not consummated, it is anticipated that we will be delisted from the Nasdaq Capital Market and may need to consider whether to remain a public company. For risks related to a delisting from the Nasdaq Capital Market, see “-In the event that we fail to satisfy any of the listing requirements of Nasdaq, our common stock may be delisted, which could affect our market price and liquidity,” in this Annual Report.

We may engage in the sale, license, transfer, disposition, divestiture or other monetization transaction Pulmatrix Legacy Business.

There can be no assurance that we will be able to conduct such transactions on favorable terms. Likewise, if the Merger is not completed, our ongoing businesses would be significantly impacted if assets of our business as conducted at any time prior to the date of the Merger Agreement (the “Pulmatrix Legacy Business”) is divested prior to the non-completion of the Merger.

The issuance of shares of our common stock to Cullgen stockholders in the Merger will substantially dilute the voting power of our current stockholders. Having a minority share position will reduce the influence that current stockholders have on our management.

Pursuant to the terms of the Merger Agreement, at the First Effective Time, we will issue (or reserve for future issuance) approximately 97,519,045 shares of our common stock using the assumed Exchange Ratio of 1.2491 (which is subject to change depending on the net amount of cash we have and the number of our and Cullgen’s outstanding securities at the First Effective Time), without giving effect to the proposed reverse stock split contemplated by the Reverse Stock Split Proposal (as defined herein), to Cullgen stockholders as merger consideration. As a result, upon completion of the Merger, our securityholders as of immediately prior to the Merger are expected to own approximately 3.6145% of the outstanding shares of the Combined Company on a fully-diluted basis, as further described under “The Merger-Exchange Ratio” in the proxy statement/prospectus. Accordingly, the issuance of the shares of our common stock to Cullgen stockholders in the Merger will significantly reduce the ownership stake and relative voting power of each share of our common stock held by current stockholders. Consequently, following the Merger, the ability of current stockholders to influence Combined Company management will be substantially reduced.

The issuance, or expected issuance, of our common stock in connection with the Merger could decrease the market price of our common stock.

In connection with the Merger and as part of the merger consideration, we expect to issue shares of common stock to Cullgen stockholders. The anticipated issuance of our common stock in the Merger may result in fluctuations in the market price of our common stock, including a stock price decrease. In addition, the perception in the market that the holders of a large number of shares of our common stock may intend to sell shares could reduce the market price of our common stock.

The intended benefits of the Merger may not be realized.

The Merger poses risks for our and Cullgen’s ongoing operations, including, among others:

As a result of the foregoing, the Combined Company may be unable to realize the full strategic and financial benefits currently anticipated from the Merger, and we or Cullgen cannot assure you that the Merger will be accretive to us or Cullgen in the near term or at all. Furthermore, if we or Cullgen fail to realize the intended benefits of the Merger, the market price of the Combined Company’s common stock could decline to the extent that the market price reflects those benefits. Our stockholders will have experienced substantial dilution of their ownership interests in us without receiving any commensurate benefit, or only receiving part of the commensurate benefit to the extent the Combined Company is able to realize only part of the strategic and financial benefits currently anticipated from the Merger.

Because the lack of a public market for Cullgen common stock makes it difficult to evaluate the fairness of the Merger, Cullgen stockholders may receive consideration in the Merger that is greater than or less than the fair market value of Cullgen common stock.

The outstanding Cullgen common stock is privately held and is not traded in any public market. The lack of a public market makes it extremely difficult to determine the fair market value of Cullgen shares. Since the percentage of our common stock to be issued to Cullgen stockholders was determined based on negotiations between the parties, it is possible that the value of our common stock to be issued in connection with the Merger will be greater than the fair market value of Cullgen shares. Alternatively, it is possible that the value of the shares of our common stock to be issued in connection with the Merger will be less than the fair market value of Cullgen shares.

Transfers of the Combined Company’s securities utilizing Rule 144 of the Securities Act may be limited.

To the extent that we complete a sale of the assets of the Pulmatrix Legacy Business prior to completion of the Merger or are otherwise deemed a shell company, a significant portion of the Combined Company’s securities will be restricted from immediate resale. Holders should be aware that transfers of the Combined Company’s securities pursuant to Rule 144 may be limited as Rule 144 is not available, subject to certain exceptions, for the resale of securities initially issued by shell companies (other than business combination related shell companies) or issuers that have been at any time previously a shell company. Our expected disposal of our historical assets and operations in connection with the Merger with Cullgen will make us a shell company. We anticipate that following the consummation of the Merger, the Combined Company will no longer be a shell company. As a result, we anticipate that holders will not be able to sell their restricted Combined Company securities pursuant to Rule 144 without registration until one year after we file the Current Report on Form 8-K following the Closing that includes the required Form 10 information that reflects that the Combined Company is no longer a shell company.

Our expected disposal of our historical assets and operations in connection with our proposed Merger with Cullgen will make us a shell company. As a result, we will be subject to more stringent reporting requirements, offering limitations and resale restrictions.

We are seeking to divest our three remaining ongoing development programs, PUR3100, PUR1800 and its legacy technology and intellectual property. If deemed necessary by us, such a transaction may be contingent upon obtaining stockholder approval. As such, if successful in the divestment or if otherwise is deemed a shell company, we expect to become a shell company prior to or upon consummation of the Merger, and our Merger with Cullgen would be subject to the requirements applicable to shell company business combinations; provided, however, that if the Merger is not consummated, the disposal of our legacy technology and intellectual property is not expected to occur and we would therefore not expect to become a shell company.

The requirements applicable to shell company business combinations are as follows:

The foregoing SEC requirements would increase the Combined Company’s time and cost of raising capital, offering stock under equity plans, and complying with securities laws. Further, such requirements will add burdensome restrictions on the resale of Combined Company shares by affiliates of Cullgen and any holders of “restricted” or “control” securities.

Directors and officers of us and Cullgen may have interests in the Merger that are different from, or in addition to, those of our stockholders and Cullgen stockholders generally that may influence them to support or approve the Merger.

Our and Cullgen’s officers and directors may have interests in the Merger that are different from, or are in addition to, those of our stockholders and Cullgen stockholders generally. Effective upon the Closing, Ying Luo, Ph.D., Thomas Eastling and Yue Xiong, Ph.D. are expected to be employed as executive officers by the Combined Company. It is expected that five directors designated by Cullgen, Drs. Luo and Xiong, Mr. Eastling, Claire Weston, Ph.D. and Maxwell Kirkby, and one director of our existing board of directors to be agreed to by Cullgen (which such director has not been identified as of the date of this Annual Report) are to be appointed as Combined Company directors after the completion of the Merger and will receive cash and equity compensation in consideration for such service as described in more detail in the section titled “Management Following the Merger” beginning on page 284 of the proxy statement/prospectus. Upon the Merger, the vesting of outstanding equity awards held by our current directors and officers will accelerate. Each outstanding option to acquire shares of Cullgen common stock held by Cullgen executive officers and directors will be converted into an option to acquire shares of our common stock.

In addition, our and Cullgen’s directors and executive officers also have certain rights to indemnification or to directors’ and officers’ liability insurance that will survive the completion of the Merger. These interests may have influenced our and Cullgen’s directors and executive officers to support or recommend the proposals presented to our and Cullgen’s stockholders. See the sections titled “The Merger-Interests of Pulmatrix Directors and Executive Officers in the Merger” beginning on page 124 and “The Merger-Interests of Cullgen Directors and Executive Officers in the Merger” beginning on page 126 of the proxy statement/prospectus.

If the Merger is completed, Cullgen executive officers and Cullgen appointees to the Combined Company board of directors will have the ability to significantly influence the Combined Company’s management and business affairs, as well as matters submitted to the Combined Company board of directors or stockholders for approval, especially if they decide to act together with the current Cullgen stockholders.

Upon completion of the Merger, the former Cullgen securityholders are expected to own approximately 96.3655% of the outstanding shares of the Combined Company on a fully diluted basis, excluding the effects of adjustments based on Pulmatrix’s Net Cash (as defined in the Merger Agreement). If the Merger is completed, the Combined Company is expected to be led by Cullgen executive officers. Furthermore, the Combined Company’s anticipated board of directors will consist of six members, five of which will be appointed by Cullgen pursuant to the terms of the Merger Agreement and one of which will be an existing member of the Pulmatrix board of directors to be agreed to by Cullgen. As a result, such persons, if they choose to act together, will have the ability to significantly influence the Combined Company’s management and business affairs, as well as matters submitted to the Combined Company board of directors or stockholders for approval.

The announcement and pendency of the Merger could have an adverse effect on our or Cullgen’s business, financial condition, results of operations or business prospects.

The announcement and pendency of the Merger could disrupt our and/or Cullgen’s businesses in the following ways, among others:

Should they occur, any of these matters could adversely affect the businesses of, or harm the financial condition, results of operations or business prospects of, us or Cullgen.

During the pendency of the Merger, we or Cullgen may not be able to enter into a business combination with another party and will be subject to contractual limitations on certain actions because of restrictions in the Merger Agreement.

Covenants in the Merger Agreement impede our and Cullgen’s the ability to make dispositions or acquisitions or complete other transactions that are not in the ordinary course of business pending completion of the Merger, potential spin-off of all or a portion of our assets prior to the consummation of the Merger, other than the Parent Restructuring (as defined in the Merger Agreement) and certain permitted financings as set forth in the Merger Agreement. As a result, if the Merger is not completed, the parties may be at a disadvantage to their competitors. In addition, while the Merger Agreement is in effect and subject to limited exceptions, each party is prohibited from soliciting, initiating, encouraging or taking actions designed to facilitate any inquiries or the making of any proposal or offer that could lead to the entering into certain extraordinary transactions with any third party, such as a sale of assets, an acquisition, a tender offer, a merger or other business combination outside the ordinary course of business. These restrictions may prevent each of us and Cullgen from pursuing otherwise attractive business opportunities or other capital structure alternatives and making other changes to their business or executing certain of their business strategies prior to the completion of the Merger, which could be favorable to our stockholders or Cullgen stockholders. See the section titled “The Merger Agreement-Non-Solicitation” beginning on page 143 of the proxy statement/prospectus.

Certain provisions of the Merger Agreement may discourage third parties from submitting competing proposals, including proposals that may be superior to the arrangements contemplated by the Merger Agreement.

The terms of the Merger Agreement prohibit each of us and Cullgen from soliciting competing proposals or cooperating with persons making unsolicited takeover proposals, except in limited circumstances if our board of directors determines in good faith, after consultation with its independent financial advisor and outside counsel, that an unsolicited competing proposal constitutes, or would reasonably be expected to result in, a superior competing proposal and that failure to take such action would be reasonably likely to result in a breach of the fiduciary duties of our board of directors. In the event that our board of directors withdraws or modifies its recommendation for Nasdaq Stock Issuance Proposal (as defined in the proxy statement/prospectus) based on such superior competing proposal, Cullgen may terminate the Merger Agreement. See the section titled “The Merger Agreement-Termination and Termination Fees” beginning on page 148 of the proxy statement/prospectus.

The rights of Cullgen stockholders who become our stockholders in the Merger and our stockholders following the Merger will be governed by the Certificate of Incorporation, as amended.

Upon consummation of the Merger, outstanding shares of Cullgen common stock will be converted into the right to receive shares of our common stock. Cullgen stockholders who receive shares of our common stock in the Merger will become our stockholders. As a result, Cullgen stockholders who become our stockholders will be governed by the Certificate of Amendment, rather than being governed by the Cullgen Charter. Pursuant to the Merger Agreement, the Amended and Restated Certificate of Incorporation (the “Certificate of Incorporation”) will be amended, subject to our stockholders’ approval of the applicable proposals described in the proxy statement/prospectus, immediately prior to the effective time of the Merger. See the section titled “Comparison of Rights of Holders of Pulmatrix Capital Stock and Cullgen Capital Stock” beginning on page 305 of the proxy statement/prospectus.

The Exchange Ratio is not adjustable based on the market price of our common stock, so the Merger consideration at the Closing may have a greater or lesser value than at the time the Merger Agreement was signed.

The Merger Agreement has set the Exchange Ratio (as defined in the Merger Agreement) formula for the Cullgen common stock, and the Exchange Ratio is only adjustable upward or downward to reflect our and Cullgen’s equity capitalization as of immediately prior to the effective time of the Merger and the excess cash we have at the effective time of the Merger. Any changes in the market price of common stock before the completion of the Merger will not affect the number of shares Cullgen securityholders will be entitled to receive pursuant to the Merger Agreement. Therefore, if before the completion of the Merger, the market price of our common stock declines from the market price on the date of the Merger Agreement, then Cullgen securityholders could receive merger consideration with substantially lower value. Similarly, if before the completion of the Merger, the market price of our common stock increases from the market price on the date of the Merger Agreement, then Cullgen securityholders could receive merger consideration with substantially more value for their shares of Cullgen common stock than the parties had negotiated for in the establishment of the Exchange Ratio. For a discussion of the Exchange Ratio, see the section titled “The Merger Agreement-Exchange Ratio” beginning on page 136 of the proxy statement/prospectus.

We are expected to incur substantial expenses related to the Merger with Cullgen.

We have incurred, and expect to continue to incur, substantial expenses in connection with the Merger, as well as operating as a public company. We will incur significant fees and expenses relating to legal, accounting, financial advisory and other transaction fees and costs associated with the Merger. Actual transaction costs may substantially exceed our estimates and may have an adverse effect on the Combined Company’s financial condition and operating results.

Failure to complete the Merger could negatively affect the value of our common stock and the future business and financial results of both us and Cullgen.

If the Merger is not completed, our and Cullgen’s ongoing businesses could be adversely affected. Moreover, we and Cullgen will be subject to a variety of risks associated with the failure to complete the Merger, including without limitation the following:

If the Merger is not completed, the market price of our common stock and the business and financial results of both us (including the cessation of its operations) and Cullgen could be materially affected.

The Merger is expected to result in a limitation on the Combined Company’s ability to utilize its net operating loss carryforward.

Under Section 382 of the Code, use of our net operating loss carryforwards (“NOLs”) will be limited if we experience a cumulative change in ownership of greater than 50% in a moving three-year period. As of December 31, 2024, we had approximately $70.0 million of net operating loss carryforwards, of which $3.8 million will expire, if unused, between the years 2026 and 2037. We may experience an ownership change as a result of the Merger and therefore its ability to utilize its NOLs and certain credit carryforwards remaining at the effective time of the Merger may be limited. The limitation would be determined by the fair market value of our common stock outstanding prior to the ownership change, multiplied by the applicable federal rate. Limitations imposed on us ability to utilize NOLs could cause U.S. federal and state income taxes to be paid earlier than would be paid if such limitations were not in effect and could cause such NOLs to expire unused, in each case reducing or eliminating the benefit of such NOLs.

The analysis received by our board of directors from Lucid Capital Markets, LLC has not been, and is not expected to be, updated to reflect changes in circumstances that may have occurred since the date of the analysis.

Such analysis was one of many factors considered by our board of directors in approving the Merger. The analysis does not speak as of the time the Merger will be completed or any date other than the date of such analysis. Subsequent changes in the operation and prospects of us or Cullgen, general market and economic conditions and other factors that may be beyond the control of us or Cullgen, may significantly alter the value of us or Cullgen or the prices of the shares of our common stock by the time the Merger is to be completed. The analysis does not address the fairness of the merger consideration from a financial point of view to us at the time the Merger is to be completed, or as of any other date other than the date of such analysis, and the Merger Agreement does not require that the analysis be updated, revised or reaffirmed prior to the Closing to reflect any changes in circumstances between the date of the signing of the Merger Agreement and the completion of the Merger as a condition to closing the Merger. See the section titled “The Merger-Opinion of Pulmatrix’s Financial Advisor” beginning on page 112 of the proxy statement/prospectus.

The Merger may be completed even though material adverse changes may result from the announcement of the Merger, industry-wide changes or other causes.

In general, either party can refuse to complete the Merger if there is a material adverse effect affecting the other party between November 13, 2024, the date of the Merger Agreement, and the Closing of the Merger. However, some types of changes do not permit either party to refuse to complete the Merger, even if such changes would have a material adverse effect on us or Cullgen, as the case may be:

If adverse changes occur but we and Cullgen must still complete the Merger, the market price of our common stock may suffer. For a more complete discussion of what constitutes a material adverse effect on us or Cullgen under the Merger Agreement, see the section titled “The Merger Agreement- Representations and Warranties” beginning on page 140 of the proxy statement/prospectus.

We, our Board of Directors, and/or and Cullgen may become involved in securities litigation or stockholder derivative litigation in connection with the Merger, and this could divert the attention of our and Cullgen’s management and harm our, Cullgen, and/or the Combined Company’s business, and insurance coverage may not be available or sufficient to cover all related costs, expenses, and damages.

Securities litigation or stockholder derivative litigation frequently follows the announcement of certain significant business transactions, such as the sale of a business division or announcement of a business combination transaction. We, our Board of Directors, and/or Cullgen may become involved in this type of litigation in connection with the Merger, and the Combined Company may become involved in this type of litigation in the future. Litigation often is expensive and diverts management’s attention and resources, which could adversely affect the business of us, Cullgen and the Combined Company.

In connection with the Merger Agreement and the proxy statement/prospectus, Pulmatrix has received multiple demand letters from purported Pulmatrix stockholders demanding that Pulmatrix disclose certain additional information related to the merger (the “Demands”). Pulmatrix cannot predict the outcome of the Demands. Pulmatrix believes that the claims asserted in the Demands are without merit and intends to defend against them vigorously. Additional demand letters or lawsuits arising out of the Merger may also be received or filed in the future.

We have never paid and, other than in connection with the Merger with Cullgen, does not intend to pay any cash dividends in the foreseeable future.

We have never paid cash dividends on any of its capital stock. Pursuant to the terms of the Merger Agreement, we may declare and pay a special cash dividend to our stockholders of record prior to the Merger (the “Cash Dividend”). The Cash Dividend will be up to an amount equal in the aggregate to our reasonable, good faith approximation of the amount by which Parent Net Cash (as defined in the Merger Agreement) will exceed the Cash Dividend Amount (as defined in the Merger Agreement), provided, that if the Closing Parent Net Cash is greater than $7,000,000, the Cash Dividend Amount shall not exceed (x) $4,500,000 plus (y) an amount equal to (A) 0.5 multiplied by (B) the Closing Parent Net Cash in excess of $7,000,000. There is no guarantee that the Parent Net Cash will exceed $2,500,000. The amount of the Cash Dividend is currently uncertain, pending the determination of our outstanding obligations and net cash position as of the Closing. Other than such potential special cash dividend in connection with the Closing, we do not currently anticipate declaring or paying cash dividends on its capital stock in the foreseeable future.

We are substantially dependent on our remaining employees, key contractors and consultants to facilitate the consummation of the Merger.

Our ability to successfully complete the Merger depends in large part on our ability to retain certain remaining personnel, in addition to key contractors and consultants. Despite our efforts to retain these employees, as well as key contractors and consultants, one or more may terminate their employment or services with us on short notice. The loss of the service of certain employees, key contractors or consultants could potentially harm our ability to consummate the Merger and run our day-to-day business operations, as well as fulfill our reporting obligations as a public company.

Risks Related to the Proposed Reverse Stock Split

The proposed reverse stock split may not increase the Combined Company’s common stock price over the long term.

If the proposal to approve an amendment to the Certificate of Incorporation to effect a reverse stock split of the issued and outstanding common stock at a ratio determined by our board of directors and agreed to by Cullgen as further described in the joint proxy statement/prospectus (the “Reverse Stock Split Proposal”) is approved, the Combined Company anticipates effecting a reverse stock split in order at a ratio to be determined in the future. While it is expected that the reduction in the number of outstanding shares of common stock will proportionally increase the market price of the Combined Company common stock upon effectiveness of the proposed reverse stock split, it cannot be assured that the proposed reverse stock split will result in any sustained proportionate increase in the market price of the Combined Company common stock, which is dependent upon many factors, including the business and financial performance of the Combined Company, general market conditions, and prospects for future success, which are unrelated to the number of shares of the Combined Company common stock outstanding. While the Combined Company common stock price might meet the initial listing requirements for Nasdaq initially, it cannot be assured that it will continue to do so.

The proposed reverse stock split would have the effect of increasing the amount of common stock that the Combined Company is authorized to issue without further approval by the Combined Company stockholders.

The proposed amendment to the Certificate of Incorporation in connection with the proposal to increase the number of authorized shares of common stock of the Company as set forth in the joint proxy statement/prospectus is anticipated to authorize the Combined Company to issue up to a certain number of shares of common stock yet to be determined as of the date of this Annual Report on Form 10-K, and does not anticipate reducing this amount in connection with the proposed reverse stock split. Except in certain instances, as required by law or by the rules of the securities exchange that lists the Combined Company common stock, these additional shares may be issued by the Combined Company without further vote of the Combined Company stockholders. If the Combined Company’s board of directors chooses to issue additional shares of the Combined Company common stock, such issuance could have a dilutive effect on the equity, earnings and voting interests of the Combined Company stockholders.

The proposed reverse stock split may decrease the liquidity of our common stock.

Although our board of directors believes that the anticipated increase in the market price of our common stock could encourage interest in its common stock and possibly promote greater liquidity for its stockholders, such liquidity could also be adversely affected by the reduced number of shares outstanding after the reverse stock split. The reduction in the number of outstanding shares may lead to reduced trading and a smaller number of market makers for our common stock.

The proposed reverse stock split may lead to a decrease in overall market capitalization of the Combined Company.

Should the market price of our common stock decline after the proposed reverse stock split, the percentage decline may be greater, due to the smaller number of shares outstanding, than it would have been prior to the reverse stock split. A reverse stock split is often viewed negatively by the market and, consequently, can lead to a decrease in the overall market capitalization of the Combined Company. If the per share market price does not increase in proportion to the reverse stock split ratio, then the value of the Combined Company, as measured by its stock capitalization, will be reduced. In some cases, the per-share stock price of companies that have effected reverse stock splits subsequently declined back to pre-reverse split levels and, accordingly, it cannot be assured that the total market value of our common stock will remain the same after the reverse stock split is effected, or that the proposed reverse stock split will not have an adverse effect on our common stock price due to the reduced number of shares outstanding after the proposed reverse stock split.

Risks Related to Our Business

We have a history of net losses and may experience future losses.

We have yet to establish any history of profitable operations. We reported a net loss of $9.6 million and $14.1 million for the fiscal years ended December 31, 2024 and 2023, respectively. As of December 31, 2024, we had an accumulated deficit of $297.2 million. We expect to incur additional operating losses for the foreseeable future. There can be no assurance that we will be able to achieve sufficient revenues throughout the year or be profitable in the future.

We will need to raise additional capital to meet our business requirements in the future and such capital raises may be costly or difficult to obtain and could dilute our stockholders’ ownership interests.

Our current capital will be sufficient to enable us to continue operations for at least 12 months following the filing date of this Annual Report on Form 10-K. In order to continue our operations and to fully realize all of our business objectives, absent any non-dilutive funding from a strategic partner or some other strategic transactions, we will need to raise additional capital, which may not be available on reasonable terms, or at all. For instance, we will need to raise additional funds to accomplish the following:

Any additional capital raised through the sale of equity or equity backed securities will dilute our stockholders’ ownership percentages and could also result in a decrease in the market value of our equity securities.

The terms of any securities issued by us in future financing transactions may be more favorable to new investors, and may include preferences, superior voting rights and the issuance of warrants or other derivative securities, which may have a further dilutive effect on the holders of any of our securities then outstanding.

Furthermore, any additional capital financing that we may need in the future may not be available on terms favorable to us, or at all. If we are unable to obtain such additional financing on a timely basis, we may have to curtail our development activities and growth plans and/or be forced to sell assets, perhaps on unfavorable terms, which would have a material adverse effect on our business, financial condition and results of operations, and ultimately could be forced to discontinue our operations and liquidate, in which event it is unlikely that stockholders would receive any distribution on their shares. Further, we may not be able to continue operating if we do not generate sufficient revenues from operations needed to stay in business.

In addition, we may incur substantial costs in pursuing future capital financing, including investment banking fees, legal fees, accounting fees, securities law compliance fees, printing and distribution expenses and other costs. We may also be required to recognize non-cash expenses in connection with certain securities we issue, such as convertible notes and warrants, which may adversely impact our financial condition and cause further dilution to our stockholders.

We have historically been a clinical development stage biopharmaceutical company and have never been profitable. We expect to incur additional losses in the future and may never be profitable.

We have historically been a clinical development stage biopharmaceutical company. We have not commercialized any product candidates or recognized any revenues from our product sales. All of our product candidates are still in the preclinical or clinical development stage, and none have been approved for marketing or are currently being marketed or commercialized. Our product candidates will require substantial additional development, clinical studies, regulatory clearances, and additional investments of time and capital before they can be commercialized. We cannot be certain when or if any of our product candidates will obtain the required regulatory approval.

We have never been profitable and have incurred net losses each year since our inception. Our losses are principally a result of research and development and general administrative expenses in support of our operations. We may incur substantial additional losses as we continue to focus our resources on prioritizing, selecting and advancing our product candidates. Our ability to generate revenue and achieve profitability depends mainly upon our ability, alone or with others, to successfully develop our product candidates, obtain the required regulatory approvals in various territories and commercialize our product candidates. We may be unable to achieve any or all of these goals with regard to our product candidates. As a result, we may never be profitable or achieve significant and/or sustained revenues.

All of our product candidates are still under development, and there can be no assurance of successful commercialization of any of our products.

All of our research and development programs are in developmental stages. One or more of our product candidates may fail to meet safety and efficacy standards in human testing, even if those product candidates are found to be effective in animal studies. To develop and commercialize inhaled therapeutic treatment for allergic bronchopulmonary aspergillosis (“ABPA”), acute migraine, and other iSPERSE^™-based product candidates, we must provide the FDA and foreign regulatory authorities with human clinical and non-clinical animal data that demonstrate adequate safety and effectiveness. To generate these data, we will have to subject our product candidates to substantial additional research and development efforts, including extensive non-clinical studies and clinical testing. Our approach to drug development may not be effective or may not result in the development of any drug. Currently our development efforts are primarily focused on PUR3100, PUR1800 and PUR1900. Even if PUR3100, PUR1800 and PUR1900 or our other product candidates are successful when tested in animals, such success would not be a guarantee of the safety or effectiveness of such product candidates in humans. It can take several years for a product to be approved and we may not be successful in bringing any therapeutic candidates to the market. A new drug may appear promising at an early stage of development or after clinical trials and never reach the market, or it may reach the market and not sell, for a variety of reasons. For example, the drug may:

If our delivery platform technologies or product development efforts fail to generate product candidates that lead to the successful development and commercialization of products, our business and financial condition will be materially adversely affected.

Drug development is a long, expensive and inherently uncertain process with a high risk of failure at every stage of development, and results of earlier studies and trials may not be predictive of future trial results.

We have a number of proprietary drug candidates in research and development ranging from the early research phase through preclinical testing and clinical trials. Preclinical testing and clinical trials are long, expensive and highly uncertain processes. It will take us several years to complete clinical trials and we may not have the resources to complete the development and commercialization of any of our proposed drug candidates. The start or end of a clinical trial can often be delayed or halted due to changing regulatory requirements, manufacturing challenges, required clinical trial administrative actions, slower than anticipated patient enrollment, changing standards of care, availability or prevalence of use of a competitor drug or required prior therapy, clinical outcomes, or financial constraints of us and our partners.

Drug development is a highly uncertain scientific and medical endeavor, and failure can unexpectedly occur at any stage of preclinical and clinical development. Typically, there is a high rate of attrition for drug candidates in preclinical and clinical trials due to scientific feasibility, safety, efficacy, changing standards of medical care and other variables. The risk of failure is heightened for our drug candidates that are based on new technologies, such as the application of our dry powder delivery platform, iSPERSE^™, including PUR3100, PUR1800, PUR1900 and other iSPERSE^™-based drug candidates currently in research or preclinical development. The failure of one or more of our iSPERSE^™-based drug candidates could have a material adverse effect on our business, financial condition, and results of operations.

In addition, the results of preclinical studies and clinical trials of previously published iSPERSE^™-based products may not necessarily be indicative of the results of our future clinical trials. The design of our clinical trials is based on many assumptions about the expected effects of inhaled drugs used historically in the industry and if those assumptions are incorrect, the trials may not produce statistically significant results. Preliminary results may not be confirmed upon full analysis of the detailed results of an early clinical trial. Product candidates in later stages of clinical trials may fail to show safety and efficacy sufficient to support intended use claims despite having progressed through initial clinical trials. The data collected from clinical trials of our product candidates may not be sufficient to obtain regulatory approval in the United States or elsewhere. Because of the uncertainties associated with drug development and regulatory approval, we cannot determine if, or when, we may have an approved product for commercialization or whether we will ever achieve sales of or profits on our product candidates or those we may pursue in the future.

If our collaborators are not successful, or breach their agreements with us, we may not effectively develop and market some of our therapeutic candidates.

At this time, we have entered into a co-development agreement regarding one of our therapeutic candidates and, as a result, we no longer have complete control over the development of this candidate. We may also enter into co-development agreements for our other therapeutic candidates in the future. If our collaborators do not successfully carry out their contractual duties or meet expected deadlines, or they otherwise breach their contractual obligations to us, we may be delayed or may not obtain regulatory approval for, or commercialize, our product candidates. We are also subject to the terms of such co-development agreements that may affect our ability to develop and manufacture our therapeutic candidates. As a result of such limitations, we may be unable to pursue the most efficient or profitable path in developing our therapeutic candidates.

If our relationships with these collaborators terminate, we believe that we would be able to enter into arrangements with alternative third parties. However, replacing any collaborator could delay our clinical trials and could jeopardize our ability to obtain regulatory approvals and commercialize our product candidates on a timely basis, if at all.

We may not be able to attract, retain, or manage highly qualified personnel, which could adversely impact our business.

Our future success and ability to compete in the biopharmaceutical industry is substantially dependent on our ability to identify, attract, and retain highly qualified key managerial, scientific, medical, and operations personnel. The market for key employees in the biopharmaceutical, pharmaceutical and biotechnology industries is competitive. The loss of the services of any of our principal members of management or key employees without an adequate replacement or our inability to hire new employees as needed could delay our product development efforts, harm our ability to sell our products or otherwise negatively impact our business.

The scientific, research and development personnel upon whom we have historically relied to operate our business have expertise in certain aspects of drug development and clinical development, and it may be difficult to replace these individuals. We have previously conducted our research and development operations within the greater Boston area, and this region is headquarters to many other biopharmaceutical, biotechnology, pharmaceutical, and medical technology companies, as well as many academic and research institutions, and, therefore, we face increased competition for technical and managerial personnel in this region.

In addition, we have scientific, medical and clinical advisors who assist us in designing and formulating our products and with development and clinical strategies. These advisors are not our employees and may have commitments to, or consulting or advisory contracts with, other entities that may limit their availability to us, or may have arrangements with other companies to assist in the development of products that may compete with ours.

Despite our efforts to retain valuable employees, members of our management and scientific and development teams may terminate their employment with us at any time. Although we have written employment offer letter agreements with our executive officers, our executive officers can leave their employment at any time, for any reason, with 30 days’ notice. A sustained labor shortage or increased turnover rates within our employee base could lead to increased costs, such as increased overtime to meet demand and increased wage rates to attract and retain employees, and could negatively affect our ability to efficiently operate our manufacturing and distribution facilities and overall business. If we are unable to hire and retain employees capable of performing at a high-level, or if mitigation measures we may take to respond to a decrease in labor availability, such as overtime and third-party outsourcing, have unintended negative effects, our business could be adversely affected. An overall labor shortage, lack of skilled labor, increased turnover or labor inflation could have a material adverse impact on our operations, results of operations, liquidity or cash flows. The loss of the services of any of our executive officers or our other key employees and our inability to find suitable replacements could potentially harm our business, financial condition and prospects. We do not maintain “key man” insurance policies on the lives of these individuals or the lives of any of our other employees.

We face substantial competition in the development of our product candidates and may not be able to compete successfully, and our product candidates may be rendered obsolete by rapid technological change.

The pharmaceutical and biotechnology industry is highly competitive, and we face substantial competition from many pharmaceutical, biopharmaceutical and biotechnology companies that are researching and marketing products designed to address the indications for which we are currently developing therapeutic candidates or for which we may develop product candidates in the future.

Many of our existing or potential competitors have, or have access to, substantially greater financial, research and development, production, and sales and marketing resources than we do and have a greater depth and number of experienced managers. As a result, our competitors may be better equipped than us to develop, manufacture, market and sell competing products. In addition, gaining favorable reimbursement is critical to the success of our product candidates. We are aware of many established pharmaceutical companies in the United States and other parts of the world that have or are developing technologies for inhaled drug delivery for the prevention and treatment of respiratory diseases, including GlaxoSmithKline, Mereo BioPharma, Mylan, Savara, Insmed, Satsuma, Bristol-Meyers, TFF Pharmaceuticals, Zambon Pharma and Pulmocide, which we consider our potential competitors in this regard. If we are unable to compete successfully with these and other potential future competitors, we may be unable to grow or generate revenue.

The rapid rate of scientific discoveries and technological changes could result in one or more of our product candidates becoming obsolete or noncompetitive. Our competitors may develop or introduce new products that render our iSPERSE^™ delivery technology and other product candidates less competitive, uneconomical or obsolete. Some of these technologies may have an entirely different approach or means of accomplishing similar therapeutic effects compared to our drug candidates. Our future success will depend not only on our ability to develop our product candidates but to improve them and keep pace with emerging industry developments. We cannot assure you that we will be able to do so.

We also expect to face increasing competition from universities and other non-profit research organizations. These institutions carry out substantial research and development in the areas of respiratory diseases. These institutions are becoming increasingly aware of the commercial value of their findings and are more active in seeking patent and other proprietary rights as well as licensing revenues.

The potential acceptance of therapeutics that are alternatives to ours may limit market acceptance of our product candidates, even if commercialized. Respiratory diseases, including our targeted diseases and conditions, can also be treated by other medication or drug delivery technologies. These treatments may be widely accepted in medical communities and have a longer history of use. The established use of these competitive drugs may limit the potential for our product candidates to receive widespread acceptance if commercialized.

If the third parties on which we rely to conduct our clinical trials and to assist us with preclinical development do not perform as contractually required or expected, we may not be able to obtain regulatory clearance or approval for, or to commercialize, our products.

We do not have the ability to independently conduct our preclinical and clinical trials for our products and we must rely on third parties, such as contract research organizations, medical institutions, clinical investigators and contract laboratories to conduct such trials. If these third parties do not successfully carry out their contractual duties or regulatory obligations or meet expected deadlines, if these third parties need to be replaced, or if the quality or accuracy of the data they obtain is compromised due to the failure to adhere to our clinical protocols or regulatory requirements or for other reasons, our preclinical development activities or clinical trials may be extended, delayed, suspended or terminated, and we may not be able to obtain regulatory approval for, or successfully commercialize, our products on a timely basis, if at all, and our business, operating results and prospects may be adversely affected. Furthermore, our third-party clinical trial investigators may be delayed in conducting our clinical trials for reasons outside of our control, such as, but not limited to, patient enrollment.

We rely on third-party contract vendors to manufacture and supply us with high quality active pharmaceutical ingredients and manufacture our therapeutic candidates in the quantities we require on a timely basis.

We currently do not manufacture any active pharmaceutical ingredients (“APIs”). Instead, we rely on third-party vendors for the manufacture and supply of our APIs that are used to formulate our therapeutic candidates. We also do not currently own or operate manufacturing facilities and therefore rely, and expect to continue to rely, on third parties to manufacture clinical and commercial quantities of our therapeutic candidates and for quality assurance related to regulatory compliance. If these suppliers or manufacturers are incapable or unwilling to meet our current or future needs at our standards or on acceptable terms, if at all, we may be unable to locate alternative suppliers or manufacturers on acceptable terms, if at all, or produce necessary materials or components on our own.

While there may be several alternative suppliers of API in the market, changing API suppliers or finding and qualifying new API suppliers can be costly and can take a significant amount of time. Many APIs require significant lead time to manufacture. There can also be challenges in maintaining similar quality or technical standards from one manufacturing batch to the next. We could experience a delay in conducting clinical trials of or obtaining regulatory approval for PUR3100, PUR1800, PUR1900 or our other drug candidates and incur additional costs if we changed API suppliers for any reason. Similarly, replacing our manufacturers could cause us to incur added costs and experience delays in identifying, engaging, qualifying and training any such replacements.

If we are not able to find stable, affordable, high quality, or reliable supplies of the APIs, or if we are unable to maintain our existing or future third-party manufacturing arrangements, we may not be able to produce enough supply of our therapeutic candidates or commercialize any therapeutic candidates on a timely and competitive basis, which could adversely affect our business, financial condition or results of operations.

Supply chain and shipping disruptions may result in shipping delays, a significant increase in shipping costs, and could increase product costs and result in lost sales and reputational damage, which may have a material adverse effect on our business, operating results and financial condition.

Our third-party manufacturers and suppliers have experienced, and may continue to experience, supply chain disruption and shipping disruptions, including disruptions or delays in loading container cargo in ports of origin or off-loading cargo at ports of destination, congestion in port terminal facilities, labor supply and shipping container shortages, inadequate equipment and persons to load, dock and offload container vessels and for other reasons. These disruptions may impact our ability to receive our raw materials and certain components required for the manufacture of our clinical trial materials or products in the future, to distribute our products in a cost-effective and timely manner and to meet demand, all of which could have an adverse effect on our financial condition and results of operations. There can be no assurance that further unforeseen events impacting the supply chain will not have a material adverse effect on us in the future. Additionally, the impacts that supply chain disruptions have on our third-party manufacturers and suppliers are not within our control. It is not currently possible to predict how long it will take for these supply chain disruptions to cease or ease. Prolonged supply chain disruption that may impact us or our manufacturers and suppliers could interrupt or delay our clinical trials, product manufacturing, increase raw material and product lead times, increase raw material and product costs, impact our ability to meet customer demand and result in lost sales and reputational damage, all of which could have a material adverse effect on our business, financial condition and results of operations.

We may not be successful in negotiating for an appropriate price in a future sale or assignment of our rights related to our current drug candidates.

We may seek to sell or assign our rights related to our current drug candidates. If completed, any such sale or assignment may be at a substantial discount, the consideration received may not accurately represent the value of the assets sold or assigned and our stockholders may not be entitled to participate in the future prospects of such drug candidates.

Our failure to successfully acquire, develop and market additional drug candidates or approved drug products could impair our ability to grow.

As part of our growth strategy, we may evaluate, acquire, license, develop and/or market additional product candidates and technologies, subject to the availability of adequate financing. However, our internal research capabilities are limited, and we may be dependent upon pharmaceutical and biotechnology companies, academic scientists and other researchers to sell or license products or technology to us. The success of this strategy depends partly upon our ability to identify, select and acquire promising pharmaceutical product candidates and products. The process of proposing, negotiating and implementing a license or acquisition of a product candidate or approved product is lengthy and complex. Other companies, including some with substantially greater financial, marketing and sales resources, may compete with us for the license or acquisition of product candidates and approved products. We have limited resources to identify and execute the acquisition or in-licensing of third-party products, businesses and technologies and integrate them into our current infrastructure. Moreover, we may devote resources to potential acquisitions or in-licensing opportunities that are never completed, or we may fail to realize the anticipated benefits of such efforts. We may not be able to acquire the rights to additional product candidates on terms that we find acceptable, or at all.

Any product candidate that we acquire may require additional development efforts prior to commercial sale, including extensive clinical testing and approval by the FDA and applicable foreign regulatory authorities. All product candidates are prone to risks of failure typical of pharmaceutical product development, including the possibility that a product candidate will not be shown to be sufficiently safe and effective for approval by regulatory authorities. In addition, we cannot provide assurance that any products that we develop or approved products that we acquire will be manufactured profitably or achieve market acceptance. We cannot guarantee that we will be able to successfully conduct the preclinical studies of the identified potential product candidates as anticipated.

Our business strategy may include entry into additional collaborative or license agreements. We may not be able to enter into collaborative or license agreements or may not be able to negotiate commercially acceptable terms for these agreements.

Our current business strategy may include the entry into additional collaborative or license agreements for the development and commercialization of our product candidates and technologies. The negotiation and consummation of these types of agreements typically involve simultaneous discussions with multiple potential collaborators or licensees and require significant time and resources. In addition, in attracting the attention of pharmaceutical and biotechnology company collaborators or licensees, we compete with numerous other third parties with product opportunities as well as the collaborators’ or licensees’ own internal product opportunities. We may not be able to consummate collaborative or license agreements, or we may not be able to negotiate commercially acceptable terms for these agreements.

If we do enter into such arrangements, we could be dependent upon the subsequent success of these other parties in performing their respective responsibilities and the cooperation of our partners. Our collaborators may not cooperate with us or perform their obligations under our agreements with them. We cannot control the amount and timing of our collaborators’ resources that will be devoted to researching our product candidates pursuant to our collaborative agreements with them. Our collaborators may choose to pursue existing or alternative technologies in preference to those being developed in collaboration with us. If we do not consummate collaborative or license agreements, we may use our financial resources more rapidly on our product development efforts, continue to defer certain development activities or forego the exploitation of certain geographic territories, any of which could have a material adverse effect on our business prospects. Further, we may not be successful in overseeing any such collaborative arrangements. If we fail to establish and maintain necessary collaborative or license relationships, our business prospects could suffer.

We may be subject to claims that our employees, independent consultants or agencies have wrongfully used or inadvertently disclosed confidential information of third parties.

We employ individuals and contract with independent consultants and agencies that may have previously worked at or conducted business with third parties; and, we may be subject to claims that we or our employees, consultants or agencies have inadvertently or otherwise used or disclosed confidential information of our employees’ former employers or other third parties. We may also be subject to claims that our employees’ former employers or other third parties have an ownership interest in our patents. Litigation may be necessary to defend against these claims. There is no guarantee of success in defending these claims, and if we are successful, litigation could result in substantial cost and be a distraction to our management and other employees.

Market and economic conditions may negatively impact our business, financial condition and share price.

Concerns over inflation, geopolitical issues, the U.S. financial markets and a declining real estate market, unstable global credit markets and financial conditions, and volatile oil prices have led to periods of significant economic instability, diminished liquidity and credit availability, declines in consumer confidence and discretionary spending, diminished expectations for the global economy and expectations of slower global economic growth going forward, increased unemployment rates, and increased credit defaults in recent years. Our general business strategy may be adversely affected by any such economic downturns, volatile business environments and continued unstable or unpredictable economic and market conditions. If these conditions continue to deteriorate or do not improve, it may make any necessary debt or equity financing more difficult to complete, more costly, and more dilutive. In addition, there is a risk that one or more of our current and future service providers, manufacturers, suppliers, hospitals and other medical facilities, our third-party payors, and other partners could be negatively affected by difficult economic times, which could adversely affect our ability to attain our operating goals on schedule and on budget or meet our business and financial objectives.

If we fail to maintain proper and effective internal controls, our ability to produce accurate and timely financial statements could be impaired, which could harm our operating results, our ability to operate our business and investors’ views of us.

Ensuring that we have adequate internal financial and accounting controls and procedures in place so that we can produce accurate financial statements on a timely basis is a costly and time-consuming effort that will need to be evaluated frequently. Section 404 of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act”) requires public companies to conduct an annual review and evaluation of their internal controls. Our failure to maintain the effectiveness of our internal controls in accordance with the requirements of the Sarbanes-Oxley Act could have a material adverse effect on our business. We could lose investor confidence in the accuracy and completeness of our financial reports, which could have an adverse effect on the price of our common stock.

Our ability to use our net operating loss carryforwards to offset future taxable income may be subject to certain limitations

Our ability to use our net operating loss carryforwards to offset future taxable income may be subject to certain limitations. In general, under Section 382 of the Internal Revenue Code of 1986, as amended (the “Code”) a corporation that undergoes an “ownership change” is subject to annual limitations on its ability to use its pre-change net operating loss carryforwards or other tax attributes (“NOLs”), to offset future taxable income or reduce taxes. Our past issuances of stock and other changes in our stock ownership may have resulted in ownership changes within the meaning of Section 382 of the Code; accordingly, our pre-change NOLs may be subject to limitation under Section 382. If we determine that we have not undergone an ownership change, the Internal Revenue Service could challenge our analysis, and our ability to use our NOLs to offset taxable income could be limited by Section 382 of the Code. Future changes in our stock ownership, some of which are outside of our control, could result in ownership changes under Section 382 of the Code further limiting our ability to utilize our NOLs. Furthermore, our ability to use NOLs of companies that we may acquire in the future may be subject to limitations. For these reasons, we may not be able to use a material portion of the NOLs, even if we attain profitability.

Our business is subject to cybersecurity risks.

Our operations are increasingly dependent on information technologies and services. Threats to information technology systems associated with cybersecurity risks and cyber incidents or attacks continue to grow, and include, among other things, storms and natural disasters, terrorist attacks, utility outages, theft, viruses, phishing, malware, design defects, human error, and complications encountered as existing systems are maintained, repaired, replaced, or upgraded. Risks associated with these threats include, among other things:

Although we utilize various procedures and controls to mitigate our exposure to such risk, cybersecurity attacks and other cyber events are evolving and unpredictable. Moreover, we have no control over the information technology systems of third parties conducting our clinical trials, our suppliers, and others with which our systems may connect and communicate. As a result, the occurrence of a cyber incident could go unnoticed for a period of time.

We have cybersecurity insurance coverage in the event we become subject to various cybersecurity attacks, however, we cannot ensure that it will be sufficient to cover any particular losses we may experience as a result of such cyberattacks. Any cyber incident could have a material adverse effect on our business, financial condition and results of operations.

Risks Related to Regulatory Matters

Our product candidates must undergo rigorous nonclinical and clinical testing, and we must obtain regulatory approvals, which could be costly and time-consuming and subject us to unanticipated delays or prevent us from marketing any products. We cannot be certain that any of our current and future product candidates will receive regulatory approval, and without regulatory approval we will not be able to market our product candidates.

Our ability to generate revenue related to product sales, if ever, will depend on the successful development and regulatory approval of our product candidates. We currently have no products approved for sale, and we cannot guarantee that we will ever have marketable products. The development of a product candidate and issues relating to its approval and marketing are subject to extensive regulation, including regulation for safety, efficacy and quality, by the FDA in the United States and comparable regulatory authorities in other countries, with regulations differing from country to country. The FDA regulations and the regulations of comparable foreign regulatory authorities are wide-ranging and govern, among other things:

Clinical testing can be costly and take many years, and the outcome is uncertain and susceptible to varying interpretations. We cannot predict whether our current or future trials and studies will adequately demonstrate the safety and efficacy of any of our product candidates or whether regulators will agree with our conclusions regarding the preclinical studies and clinical trials we have conducted to date, including the clinical trials for PUR1900. The clinical trials of our product candidates may not be completed on schedule, the FDA or foreign regulatory agencies may order us to stop or modify our research, or these agencies may not ultimately approve any of our product candidates for commercial sale. The data collected from our clinical trials may not be sufficient to support regulatory approval of our various product candidates. Even if we believe the data collected from our clinical trials are sufficient, the FDA has substantial discretion in the approval process and may disagree with our interpretation of the data. If the FDA believes our clinical trials fail to demonstrate the requisite safety and efficacy of a product candidate, we will not obtain regulatory approval.

We are not permitted to market our product candidates in the United States until we receive approval of an NDA from the FDA. Obtaining approval of an NDA is a lengthy, expensive and uncertain process, and we may not be successful in obtaining approval. The FDA review processes can take years to complete and approval is never guaranteed. We cannot be certain that any of our submissions will be accepted for filing and review by the FDA.

The requirements governing the conduct of clinical trials and manufacturing and marketing of our product candidates outside the United States vary widely from country to country. Foreign approvals may take longer to obtain than FDA approvals and can require, among other things, additional testing and different clinical trial designs. Foreign regulatory approval processes include essentially all of the risks associated with the FDA approval processes. Some of those agencies also must approve prices of the products. Approval of a product by the FDA does not ensure approval of the same product by the health authorities of other countries, or vice versa. In addition, changes in regulatory policy in the United States or in foreign countries for product approval during the period of product development and regulatory agency review of each submitted new application may cause delays or rejections.

If we are unable to obtain approval from the FDA or other regulatory agencies for our product candidates, or if, subsequent to approval, we are unable to successfully market and commercialize our product candidates, we will not be able to generate sufficient revenue to become profitable. Furthermore, the introduction of government price controls or other price-reducing regulations may affect the prices we obtain on our product candidates, if approved and commercialized.

We have limited experience in filing and pursuing applications necessary to gain regulatory approvals, which may impede our ability to obtain timely approvals from the FDA or foreign regulatory agencies, if at all.

Before obtaining regulatory approval, the FDA requires the sponsor to file a marketing application, which must include all required information detailed in FDA regulations. If the application is incomplete, the FDA may refuse to review the application until the application is complete, which may, for example, require additional clinical trials. As a company, we have no experience in late-stage regulatory filings, such as preparing and submitting NDAs, which may place us at risk of delays, overspending and human resources inefficiencies. Any delay in obtaining, or inability to obtain, regulatory approval could harm our business.

Any failure by us to comply with existing or future regulations could harm our reputation and operating results.

We will be subject to extensive regulation by U.S. federal and state and foreign governments in each of the markets where we intend to sell our product candidates if and after we are approved. If we fail to comply with applicable regulations, including the FDA’s pre-or post-approval cGMP requirements, then the FDA or other foreign regulatory authorities could sanction us. Even if a drug is FDA-approved, regulatory authorities may impose significant restrictions on a product’s indicated uses or marketing or impose ongoing requirements for potentially costly post-marketing studies.

If a regulatory agency discovers previously unknown problems with a product, such as adverse events of unanticipated severity or frequency, or problems with the facility where the product is manufactured, or disagrees with the promotion, marketing or labeling of the product, the regulatory agency may impose restrictions on that product or us, including requiring withdrawal of the product from the market. If we fail to comply with applicable regulatory requirements, a regulatory agency or enforcement authority may:

Any government investigation of alleged violations of law could require us to expend significant time and resources in response and could generate negative publicity. Any failure to comply with ongoing regulatory requirements may significantly and adversely affect our ability to commercialize and generate revenue from our product candidates. If regulatory sanctions are applied or if regulatory approval is withdrawn, our value and operating results will be adversely affected. Additionally, if we are unable to generate revenue from sales of our product candidates, our potential for achieving profitability will be diminished and the capital necessary to fund our operations will be increased.

Any action against us for violation of these laws, even if we successfully defend against it, could cause us to incur significant legal expenses, divert management’s attention from the operation of our business and damage our reputation. We expend significant resources on compliance efforts and such expenses are unpredictable and might adversely affect our results. Changing laws, regulations and standards might also create uncertainty, higher expenses and increase insurance costs.

While we believe we understand the current laws and regulations to which our products are and will be subject, laws and regulations are constantly changing, as are administrative interpretations of laws and regulations. If we fail to comply with future changes in laws, regulations, or administrative interpretations, we may be unable to gain regulatory approval. In addition, any changes in current laws or regulations may result in an increase in costs for clinical trials and other requirements to gain regulatory approval. Finally, if we are slow to comply with new laws or regulations, our ability to gain regulatory approval may be substantially delayed.

Recently, President Trump’s administration issued a memorandum instructing U.S. executive agencies to prepare for reductions in workforce at governmental agencies, which likely includes the FDA. If the new administration takes action that substantially reduces FDA’s workforce, in particular, at the Center for Drug Evaluation and Research, we may face significant delay in obtaining approval and subsequently marketing our product candidates.

We and our third-party manufacturers are, and will be, subject to regulations of the FDA and other foreign regulatory authorities.

We and our contract manufacturers are, and will be, required to adhere to laws, regulations and guidelines of the FDA or other foreign regulatory authorities setting forth current good manufacturing practices. These laws, regulations and guidelines cover all aspects of the manufacturing, testing, quality control and recordkeeping relating to our therapeutic candidates. We and our third-party manufacturers may not be able to comply with applicable laws, regulations and guidelines. We and our contract manufacturers are and will be subject to unannounced inspections by the FDA, state regulators and similar foreign regulatory authorities outside the United States. Our failure, or the failure of our third-party manufacturers, to comply with applicable laws, regulations and guidelines could result in the imposition of sanctions on us, including fines, injunctions, civil penalties, refusal of regulatory authorities to grant marketing approval of our therapeutic candidates, delays, suspension or withdrawal of approvals, license revocation, seizures or recalls of our therapeutic candidates, operating restrictions and criminal prosecutions, any of which could significantly and adversely affect regulatory approval and supplies of our therapeutic candidates, and materially and adversely affect our business, financial condition and results of operations.

Failure to establish that our manufacturing capabilities are sufficient to comply with FDA regulatory requirements during clinical trials, including cGMP requirements, may result in an inability to gain regulatory approval for our product candidates. While we currently believe our iSPERSE technology will allow us to deliver our product candidates in compliance with FDA cGMPs and other manufacturing regulations, the FDA may disagree. This could result in an inability to receive timely regulatory approval, if at all, for our iSPERSE product candidates.

Even if we obtain regulatory approvals, our therapeutic candidates will be subject to ongoing regulatory review. If we fail to comply with continuing U.S. and applicable foreign laws, regulations and guidelines, we could lose those approvals, and our business would be seriously harmed.

Even if our therapeutic candidates receive regulatory approval, we or our commercialization partners, as applicable, will be subject to ongoing reporting obligations, including pharmacovigilance, and the therapeutic candidates and the manufacturing operations will be subject to continuing regulatory review, including inspections by the FDA or other foreign regulatory authorities. The results of this ongoing review may result in the withdrawal of a therapeutic candidate from the market, the interruption of the manufacturing operations and/or the imposition of new product labeling (such as warnings) and/or marketing limitations. Since many more patients are exposed to drugs following their marketing approval, serious but infrequent adverse reactions that were not observed in clinical trials may be observed during the commercial marketing of the therapeutic candidate. In addition, the manufacturer and the manufacturing facilities that we or our commercialization partners use to produce any therapeutic candidate will be subject to periodic review and inspection by the FDA and other foreign regulatory authorities. Later discovery of previously unknown problems with any therapeutic candidate, manufacturer or manufacturing process, or failure to comply with rules and regulatory requirements, may result in actions, including but not limited to the following:

If we or our commercialization partners, suppliers, third-party contractors or clinical investigators are slow to adapt, or are unable to adapt, to changes in existing regulatory requirements or the adoption of new regulatory requirements or policies, we or our commercialization partners may lose marketing approval for any of our therapeutic candidates if any of our therapeutic candidates are approved, resulting in decreased or lost revenue from milestones, product sales or royalties.

Our employees may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements and insider trading.

We are exposed to the risk of employee fraud or other misconduct. Misconduct by employees could include intentional failures to comply with any regulations applicable to us, to provide accurate information to regulatory authorities, to comply with manufacturing standards we may have established, to comply with federal and state healthcare fraud and abuse laws and regulations, or to report financial information or data accurately or disclose unauthorized activities to us. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, misconduct, kickbacks, self-dealing and other abusive practices. These laws and regulations may restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs and other business arrangements. Employee misconduct could also involve the improper use of information obtained in the course of clinical trials, which could result in regulatory sanctions and serious harm to our reputation. We have adopted a Code of Business Conduct, but it is not always possible to identify and deter employee misconduct, and the precautions we take to detect and prevent this activity may not be effective in controlling unknown or unmanaged risk.

If we fail to comply with federal or state “fraud and abuse” laws, the failure to comply with these laws may adversely affect our business, financial condition and results of operations.

In the United States, we will be subject to various federal and state health care “fraud and abuse” laws, including anti-kickback laws, false claims laws and other laws intended to reduce fraud and abuse the healthcare industry, which could affect us, particularly upon successful commercialization of our products in the United States. The federal Anti-Kickback Statute makes it illegal for any person, including a prescription drug manufacturer (or a party acting on our behalf), to knowingly and willfully solicit, receive, offer or pay any remuneration in exchange for or to induce the referral of an individual for, or the purchase, order or recommendation of, any good or service, including the purchase, order or prescription of a particular drug for which payment may be made under a federal health care program, such as Medicare or Medicaid. Under federal government regulations, some arrangements, known as safe harbors, are deemed not to violate the federal Anti-Kickback Statute. However, these laws are broadly written, and it is often difficult to determine precisely how the law will be applied in specific circumstances. Accordingly, it is possible that our practices may be challenged under the federal Anti-Kickback Statute. False claims laws prohibit anyone from knowingly and willfully presenting or causing to be presented for payment to third-party payors, including government payors, claims for reimbursed drugs or services that are false or fraudulent, claims for items or services that were not provided as claimed, or claims for medically unnecessary items or services. Cases have been brought under false claims laws alleging that off-label promotion of pharmaceutical products or the provision of kickbacks has resulted in the submission of false claims to governmental healthcare programs. Under the Health Insurance Portability and Accountability Act of 1996, we are prohibited from knowingly and willfully executing a scheme to defraud any healthcare benefit program, including private payors, or knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services. Violations of fraud and abuse laws may be punishable by criminal and/or civil sanctions, including fines, penalties and/or exclusion or suspension from federal and state healthcare programs such as Medicare and Medicaid and debarment from contracting with the U.S. government. In addition, private individuals have the ability to bring actions on behalf of the government under the federal False Claims Act as well as under the false claims laws of several states.

Many states have adopted laws similar to the federal Anti-Kickback Statute, some of which apply to the referral of patients for, or purchase, order or recommendation of, goods or services reimbursed by any source, not just governmental payors. The scope and enforcement of these laws are uncertain and subject to change in the current environment of healthcare reform. We cannot predict the impact on our business, financial condition nor results of operations of any changes in these laws. Any state or federal regulatory review of us, regardless of the outcome, would be costly and time-consuming. Law enforcement authorities are increasingly focused on enforcing these laws, and if we are challenged under of one of these laws, we could be required to pay a fine and/or penalty and could be suspended or excluded from participation in federal or state healthcare programs, and our business, results of operations and financial condition may be adversely affected.

Legislative or regulatory reform of the U.S. healthcare system may adversely affect our business.

On March 23, 2010, President Obama signed the “Patient Protection and Affordable Care Act” (P.L. 111-148) (the “ACA”) and on March 30, 2010, he signed the “Health Care and Education Reconciliation Act” (P.L. 111-152), collectively commonly referred to as the “Healthcare Reform Law.” The Healthcare Reform Law included a number of new rules regarding health insurance, the provision of healthcare, conditions to reimbursement for healthcare services provided to Medicare and Medicaid patients, and other healthcare policy reforms. Through the law-making process, substantial changes have been and continue to be made to the current system for paying for healthcare in the U.S., including changes made to extend medical benefits to certain Americans who lacked insurance coverage and to contain or reduce healthcare costs (such as by reducing or conditioning reimbursement amounts for healthcare services and drugs, and imposing additional taxes, fees, and rebate obligations on pharmaceutical and medical device companies). This legislation was one of the most comprehensive and significant reforms ever experienced by the U.S. in the healthcare industry and has significantly changed the way healthcare is financed by both governmental and private insurers. This legislation has impacted the scope of healthcare insurance and incentives for consumers and insurance companies, among others. Additionally, the Healthcare Reform Law’s provisions were designed to encourage providers to find cost savings in their clinical operations. Pharmaceuticals represent a significant portion of the cost of providing care. This environment has caused changes in the purchasing habits of consumers and providers and resulted in specific attention to the pricing negotiation, product selection and utilization review surrounding pharmaceuticals which could result in lower pricing and/or reduced market acceptance for any drug products we may commercialize in the U.S. in the future. At this stage, it is difficult to estimate the full extent of the direct or indirect impact of the Healthcare Reform Law on us.

Further, the healthcare regulatory environment has seen significant changes in recent years and is still in flux. Legislative initiatives to modify, limit, replace, or repeal the ACA and judicial challenges have continued for over a decade. However, as of the Supreme Court’s ruling ordering the dismissal of, arguably, the most promising case challenging the ACA to-date on June 17, 2021, it appears that the ACA will remain in-effect in its current form for the foreseeable future; however, we cannot predict what additional challenges may arise in the future, the outcome thereof, or the impact any such actions may have on our business. The Biden administration also introduced various measures in 2021 focusing on healthcare and drug pricing, in particular. For example, on January 28, 2021, President Biden issued an executive order that initiated a special enrollment period for purposes of obtaining health insurance coverage through the ACA marketplace, which began on February 15, 2021, and remained open through August 15, 2021. The executive order also instructed certain governmental agencies to review and reconsider their existing policies and rules that limit access to healthcare, including among others, reexamining Medicaid demonstration projects and waiver programs that include work requirements and policies that create unnecessary barriers to obtaining access to health insurance coverage through Medicaid or the ACA. On the legislative front, the American Rescue Plan Act of 2021 was signed into law on March 11, 2021, which, in relevant part, eliminates the statutory Medicaid drug rebate cap, currently set at 100% of a drug’s average manufacturer price, for single source drugs and innovator multiple source drugs, beginning January 1, 2024. And, in July 2021, the Biden administration released an executive order entitled, “Promoting Competition in the American Economy,” with multiple provisions aimed at prescription drugs. In response, on September 9, 2021, HHS released a “Comprehensive Plan for Addressing High Drug Prices” that outlines principles for drug pricing reform and sets out a variety of potential legislative policies that Congress could pursue as well as potential administrative actions HHS can take to advance these principles. And, in August 2022, the Inflation Reduction Act (“IRA”) was signed into law, which will, among other things, allow U.S. Department of Health and Human Services (“HHS”) to negotiate the selling price of certain drugs and biologics that the Centers for Medicare & Medicaid Services (“CMS”) reimburses under Medicare Part B and Part D, although only high-expenditure single-source drugs that have been approved for at least 7 years (11 years for biologics) can be selected by CMS for negotiation, with the negotiated price taking effect two years after the selection year. The negotiated prices, which will first become effective in 2026, will be capped at a statutory ceiling price. Beginning in October 2023, the IRA also began penalizing drug manufacturers that increase prices of Medicare Part B and Part D drugs at a rate greater than the rate of inflation. The IRA permits the Secretary of HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. Manufacturers that fail to comply with the IRA may be subject to various penalties, including civil monetary penalties. The IRA also extends enhanced subsidies for individuals purchasing health insurance coverage in ACA marketplaces through plan year 2025. Additionally, in December 2023, the Biden-Harris Administration announced further related initiatives under the IRA to lower prescription costs and increase competition with help from HHS, the DOJ, and the FTC.

There is uncertainty as to what healthcare programs and regulations may be implemented or changed at the federal and/or state level in the U.S. or the effect of any future legislation or regulation. Furthermore, we cannot yet assess the impact that President Trump’s second term will have on healthcare programs and regulations or the pharmaceutical industry in general. However, it is possible that such initiatives could have an adverse effect on our ability to obtain approval and/or successfully commercialize products in the U.S. in the future, as applicable.

Risks Related to Our Financial Position and Need for Additional Capital

We will be required to raise additional capital to fund our operations, and we may not be able to continue as a going concern if we are unable to do so.

Pharmaceutical product development, which includes research and development, preclinical and clinical studies and human clinical trials, is a time-consuming and expensive process that takes years to complete. Contingent on securing additional funding, we anticipate that our expenses would remain at a high level as we pursue development of PUR3100 and PUR1800 or other iSPERSE^™-based product candidates, and/or pursue development of iSPERSE^™-based pharmaceuticals in additional indications. Based upon our current expectations, we believe that our existing capital resources will enable us to continue planned operations for at least 12 months following the filing date of this Annual Report on Form 10-K. We cannot assure you, however, that our plans will not change or that changed circumstances will not result in the depletion of our capital resources more rapidly than we currently anticipate. We will need to raise additional funds, whether through the sale of equity or debt securities, the entry into strategic business collaborations, the establishment of other funding facilities, licensing arrangements, or asset sales or other means, in order to continue our research and development and clinical trial programs for our iSPERSE^™-based product candidates and to support our other ongoing activities. However, it may be difficult for us to raise additional funds on reasonable terms or at all. Since inception, we have incurred losses each year and have an accumulated deficit of $297.2 million as of December 31, 2024, which may raise concerns about our solvency and affect our ability to raise additional capital.

The amount of additional funds we need will depend on a number of factors, including:

We have raised capital in the past primarily through debt and public offerings and private placements of stock. We may in the future pursue the sale of additional equity and/or debt securities, or the establishment of other funding facilities including asset-based borrowings. There can be no assurances, however, that we will be able to raise additional capital through such an offering on acceptable terms, or at all. Issuances of additional debt or equity securities could impact the rights of the holders of our common stock and may dilute their ownership percentage. Moreover, the establishment of other funding facilities may impose restrictions on our operations. These restrictions could include limitations on additional borrowing and specific restrictions on the use of our assets, as well as prohibitions on our ability to create liens, pay dividends, redeem our stock or make investments.

We also may seek to raise additional capital by pursuing opportunities for the licensing or sale of certain intellectual property and other assets. We cannot offer assurances, however, that any strategic collaborations, sales of securities or sales or licenses of assets will be available to us on a timely basis or on acceptable terms, if at all.

In the event that sufficient additional funds are not obtained through strategic collaboration opportunities, sales of securities, funding facilities, licensing arrangements and/or asset sales on a timely basis, we will be required to reduce expenses through the delay, reduction or curtailment of our projects, including PUR3100, PUR1800 or PUR1900 development activities, or reduction of costs for facilities and administration. Moreover, if we do not obtain such additional funds, doubt may arise about our ability to continue as a going concern and increased risk of insolvency and loss of investment to the holders of our securities. If we are or become insolvent, investors in our stock may lose the entire value of their investment.

Our long-term capital requirements are subject to numerous risks.

Our long-term capital requirements are expected to depend on many potential factors, including, among others:

We may engage in strategic transactions that could impact our liquidity, increase our expenses and present significant distractions to our management.

From time to time, we may consider strategic transactions, such as acquisitions of companies, business combinations, asset purchases and out-licensing or in-licensing of products, product candidates or technologies. Additional potential transactions that we may consider include a variety of different business arrangements, including spin-offs, strategic partnerships, joint ventures, restructurings, divestitures, business combinations and investments. Any such transaction may require us to incur non-recurring or other charges, may increase our near- and long-term expenditures and may pose significant integration challenges or disrupt our management or business, which could adversely affect our business, financial condition and results of operations. These transactions may entail numerous operational and financial risks, including:

Accordingly, although there can be no assurance that we will undertake or successfully complete any transactions of the nature described above, any transactions that we do complete may be subject to the foregoing or other risks and could have a material adverse effect on our business, financial condition and results of operations.

Risks Related to Our Intellectual Property

We may be unable to adequately protect or enforce our rights to intellectual property, causing us to lose valuable rights. Loss of patent rights may lead us to lose market share and anticipated profits.

Our success, competitive position and future revenues depend, in part, on our ability to obtain patent protection for our products, methods, processes and other technologies, to preserve our trade secrets, to prevent third parties from infringing on our proprietary rights and to operate without infringing the proprietary rights of third parties. Despite our efforts to protect our proprietary technologies and processes, it is possible that competitors or other unauthorized third parties may obtain, copy, use or disclose proprietary technologies and processes.

We try to protect our proprietary position by, among other things, filing U.S., European and other patent applications related to our product candidates, methods, processes and other technologies, to prevent third parties from infringing on our proprietary rights and to operate without infringing the proprietary rights of third parties.

Because the patent position of pharmaceutical companies involves complex legal and factual questions, we cannot predict the validity and enforceability of patents with certainty. Our issued patents may not provide us with any competitive advantages or may be held invalid or unenforceable as a result of legal challenges by third parties or could be circumvented. Our competitors may also independently develop inhaled drug delivery technologies or products similar to iSPERSE^™ and iSPERSE^™-based product candidates or design around or otherwise circumvent patents issued to us. Thus, any patents that we own may not provide any protection against competitors. Our pending patent applications, those we may file in the future or those we may license from third parties may not result in patents being issued. Even if these patents are issued, they may not provide us with proprietary protection or competitive advantages. The degree of future protection to be afforded by our proprietary rights is uncertain because legal means afford only limited protection and may not adequately protect our rights or permit us to gain or keep our competitive advantage.

Furthermore, the issuance of a patent, while presumed valid and enforceable, is not conclusive as to its validity or its enforceability and it may not provide us with adequate proprietary protection or competitive advantages against competitors with similar products. Competitors may also be able to design around our patents. Other parties may develop and obtain patent protection for more effective technologies, designs or methods. We may not be able to prevent the unauthorized disclosure or use of our technical knowledge or trade secrets by consultants, vendors, former employees and current employees.

Patent rights are territorial, and accordingly, the patent protection we do have will only extend to those countries in which we have issued patents. Even so, the laws of certain countries do not protect our intellectual property rights to the same extent as do the laws of the United States and the European Union. Competitors may successfully challenge our patents, produce similar drugs or products that do not infringe our patents, or produce drugs in countries where we have not applied for patent protection or that do not respect our patents. Furthermore, it is not possible to know the scope of claims that will be allowed in published applications and it is also not possible to know which claims of granted patents, if any, will be deemed enforceable in a court of law.

We have not pursued or maintained, and may not pursue or maintain in the future, patent protection for our product candidates in every country or territory in which we may sell our products, if approved. The laws of some foreign countries do not protect intellectual property rights to the same extent as federal and state laws in the United States. Consequently, we may not be able to prevent third parties from infringing our patents in all countries outside the United States, or from selling or importing products that infringe our patents in and into the United States or other jurisdictions.

Indeed, several companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions. The legal systems of some countries do not favor the enforcement of patents and other intellectual property rights, which could make it difficult for us to stop the infringement, misappropriation or other violation of our intellectual property rights generally. Proceedings to enforce our intellectual property rights in foreign jurisdictions could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly and our patent applications at risk of not issuing and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate, and the damages or other remedies awarded, if any, may not be commercially meaningful.

After the completion of prosecution and granting of our patents, third parties may still manufacture and/or market therapeutic candidates in infringement of our patent protected rights. Such manufacture and/or market of our product candidates in infringement of our patent protected rights is likely to cause us damage and lead to a reduction in the prices of our product candidates, thereby reducing our anticipated profits.

In addition, due to the extensive time needed to develop, test and obtain regulatory approval for our therapeutic candidates, any patents that protect our product candidate may expire during early stages of commercialization. This may reduce or eliminate any market advantages that such patents may give us. Following patent expiration, we may face increased competition through the entry of generic products into the market and a subsequent decline in market share and profits.

In addition, in some cases we may rely on our licensors to conduct patent prosecution, patent maintenance or patent defense on our behalf. Therefore, our ability to ensure that these patents are properly prosecuted, maintained, or defended may be limited, which may adversely affect our rights in our therapeutic products. Any failure by our licensors or development partners to properly conduct patent prosecution, patent maintenance or patent defense could harm our ability to obtain approval or to commercialize our products, thereby reducing our anticipated profits.

Furthermore, our ability to enforce our patent rights depends on our ability to detect infringement. It is difficult to detect infringers who do not advertise the components that are used in their products. Moreover, it may be difficult or impossible to obtain evidence of infringement in a competitor’s or potential competitor’s product, particularly in litigation in countries other than the U.S. that do not provide an extensive discovery procedure. Any litigation to enforce or defend our patent rights, if any, even if we were to prevail, could be costly and time-consuming and would divert the attention of our management and key personnel from our business operations. We may not prevail in any lawsuits that we initiate, and the damages or other remedies awarded if we were to prevail may not be commercially meaningful.

If we are unable to protect the confidentiality of our trade secrets or know-how, such proprietary information may be used by others to compete against us.

In addition to filing patents, we generally try to protect our trade secrets, know-how and technology by entering into confidentiality or non-disclosure agreements with parties that have access to us, such as our development and/or commercialization partners, employees, contractors and consultants. We also enter into agreements that purport to require the disclosure and assignment to us of the rights to the ideas, developments, discoveries and inventions of our employees, advisors, research collaborators, contractors and consultants while employed or engaged by us. However, these agreements can be difficult and costly to enforce or may not provide adequate remedies. Any of these parties may breach the confidentiality agreements and willfully or unintentionally disclose our confidential information, or our competitors might learn of the information in some other way. The disclosure to, or independent development by, a competitor of any trade secret, know-how or other technology not protected by a patent could materially adversely affect any competitive advantage we may have over any such competitor.

To the extent that any of our employees, advisors, research collaborators, contractors or consultants independently develop, or use independently developed, intellectual property in connection with any of our products, disputes may arise as to the proprietary rights to this type of information. If a dispute arises with respect to any proprietary right, enforcement of our rights can be costly and unpredictable, and a court may determine that the right belongs to a third party.

Legal proceedings or third-party claims of intellectual property infringement and other challenges may require us to spend substantial time and money and could prevent us from developing or commercializing our product candidates.

Our commercial success also depends upon our ability, and the ability of any third party with which we may partner, to develop, manufacture, market and sell our product candidates and/or products, if approved, and use our patent-protected technologies without infringing the patents of third parties. There is considerable patent litigation in the pharmaceutical industry. As the pharmaceutical industry expands and more patents are issued, we face increased risks that there may be patents issued to third parties that relate to our product candidates and technology of which we are not aware or that we must challenge to continue our operations as currently contemplated.

We may not have identified all patents, published applications or published literature that affect our business either by blocking our ability to commercialize our products or product candidates, by preventing the patentability of one or more aspects of our products or product candidates to us or our licensors, or by covering the same or similar technologies that may affect our ability to market our products and product candidates. For example, we (or the licensor of a product or product candidate to us) may not have conducted a patent clearance search sufficient to identify potentially obstructing third-party patent rights. Moreover, patent applications in the United States are maintained in confidence for up to 18 months after their filing. In some cases, however, patent applications remain confidential in the U.S. Patent and Trademark Office, or the USPTO, for the entire time prior to issuance as a U.S. patent. Patent applications filed in countries outside of the United States are not typically published until at least 18 months from their first filing date. Similarly, publication of discoveries in the scientific or patent literature often lags behind actual discoveries. We cannot be certain that we or our licensors were the first to invent, or the first to file, patent applications covering our products and candidates. We also may not know if our competitors filed patent applications for technology covered by our pending applications or if we were the first to invent the technology that is the subject of our patent applications. Competitors may have filed patent applications or received patents and may obtain additional patents and proprietary rights that block or compete with our patents.

The development, manufacture, use, offer for sale, sale or importation of our product candidates may therefore infringe on the claims of third-party patents or other intellectual property rights. The nature of claims contained in unpublished patent filings around the world is unknown to us, and it is not possible to know which countries patent holders may choose for the extension of their filings under the Patent Cooperation Treaty or other mechanisms. We may also be subject to claims based on the actions of employees and consultants with respect to the usage or disclosure of intellectual property learned at other employers. The cost to us of any intellectual property litigation or other infringement proceeding, even if resolved in our favor, could be substantial. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively because of their substantially greater financial resources. Uncertainties resulting from the initiation, continuation or defense of intellectual property litigation or other proceedings could have a material adverse effect on our ability to compete in the marketplace. Intellectual property litigation and other proceedings may also absorb significant management time. Consequently, we are unable to guarantee that we will be able to manufacture, use, offer for sale, sell or import our therapeutic candidates in the event of an infringement action.

In the event of patent infringement claims, or to avoid potential claims, we may choose or be required to seek a license from a third party and would most likely be required to pay license fees or royalties or both. These licenses may not be available on acceptable terms, or at all. Even if we were able to obtain a license, the rights may be non-exclusive, which could potentially limit our competitive advantage. Ultimately, we could be prevented from commercializing a product candidate or be forced to cease some aspect of our business operations if, as a result of actual or threatened patent infringement or other claims, we are unable to enter into licenses on acceptable terms. This inability to enter into licenses could harm our business significantly.

We may be subject to other patent-related litigation or proceedings that could be costly to defend and uncertain in their outcome.

In addition to infringement claims against us, we may in the future become a party to other patent litigation or proceedings before regulatory agencies, including interference, re-examination inter partes review, or post grant review proceedings filed with the U.S. Patent and Trademark Office or opposition proceedings in other foreign patent offices regarding intellectual property rights with respect to our therapeutic candidates, as well as other disputes regarding intellectual property rights with development and/or commercialization partners, or others with whom we have contractual or other business relationships. Post-issuance oppositions are not uncommon and we or our development and/or commercialization partners will be required to defend these opposition procedures as a matter of course. Opposition procedures may be costly, and there is a risk that we may not prevail, which could harm our business significantly.

Obtaining and maintaining patent protection depends on compliance with various procedures and other requirements, and our patent protection could be reduced or eliminated in case of non-compliance with these requirements.

Periodic maintenance fees, renewal fees, annuity fees and various other governmental fees on patents and/or applications will be due to the relevant patent agencies in several stages over the lifetime of the patents and /or applications. The relevant patent agencies require compliance with a number of procedural, documentary, fee payment and other provisions during the patent application process. In many cases, an inadvertent lapse can be cured by payment of a late fee or by other means in accordance with the applicable rules. However, there are situations in which the failure to comply with the relevant requirements can result in the abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. In such an event, our competitors might be able to use our technologies and know-how which could have a material adverse effect on our business, prospects, financial condition and results of operation.

If we fail to comply with our obligations under our license agreements, we could lose the rights to intellectual property that is important to our business.

Our current license agreements impose on us various development obligations, payment of royalties and fees based on achieving certain milestones as well as other obligations. If we fail to comply with our obligations under these agreements, the licensor may have the right to terminate the license. In addition, if the licensor fails to enforce its intellectual property, the licensed rights may not be adequately maintained. The termination of any license agreements or failure to adequately protect such license agreements could prevent us from commercializing our product candidates or possible future products covered by the licensed intellectual property. Any of these events could materially adversely affect our business, prospects, financial condition and results of operation.

We may be subject to damages resulting from claims that we or our employees have wrongfully used or disclosed alleged trade secrets of their former employers.

Our employees may have been previously employed at other companies in the industry, including our competitors or potential competitors. Although we are not aware of any claims currently pending against us, we may be subject to claims that these employees or we have inadvertently or otherwise used or disclosed trade secrets or other proprietary information of the former employers of our employees. Litigation may be necessary to defend against these claims. Even if we are successful in defending against these claims, litigation could result in substantial costs and be a distraction to management. If we fail in defending such claims, in addition to paying money claims, we may lose valuable intellectual property rights or personnel. A loss of key personnel or their work product could hamper or prevent our ability to commercialize product(s), which would materially adversely affect our commercial development efforts.

Risks Related to Our Common Stock

The price of our common stock is subject to fluctuation and has been and may continue to be volatile.

The stock market in general, and Nasdaq in particular, as well as biotechnology companies, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of small companies. The market price of our common stock may fluctuate as a result of, among other factors:

In addition, if the market for stocks in our industry or industries related to our industry, or the stock market in general, experiences a loss of investor confidence, the trading price of our common stock could fluctuate or decline for reasons unrelated to our business, financial condition and results of operations. If any of the foregoing occurs, it could cause our stock price to fall and may expose us to lawsuits that, even if unsuccessful, could be costly to defend and a distraction to management.

Financial reporting obligations of being a public company in the United States are expensive and time-consuming, and our management may be required to devote substantial time to compliance matters.

As a publicly traded company, we incur significant additional legal, accounting and other expenses. The obligations of being a public reporting company require significant expenditures, including costs resulting from public company reporting obligations under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and the rules and regulations regarding corporate governance practices, including those under the Sarbanes-Oxley Act, the Dodd-Frank Wall Street Reform and Consumer Protection Act, and the Nasdaq. These rules require the establishment and maintenance of effective disclosure and financial controls and procedures, internal control over financial reporting and corporate governance practices, among many other complex rules that are often difficult and time consuming to implement, monitor and maintain compliance with. Moreover, despite reforms made possible by the Jumpstart Our Business Startups Act of 2012, the reporting requirements, rules, and regulations will make some activities more time-consuming and costly, particularly as we are no longer an “emerging growth company.”

In addition, these rules and regulations make it more difficult and more expensive for us to obtain director and officer liability insurance. Compliance with such requirements also places demands on management’s time and attention.

In the foreseeable future, we do not intend to pay cash dividends on shares of our common stock, except the potential Cash Dividend in connection with the Merger, so any investor gains will be limited to the value of our shares.

We have not paid dividends to our stockholders since inception. Pursuant to the terms of the Merger Agreement, we may declare and pay the Cash Dividend. The Cash Dividend will be up to an amount equal in the aggregate to our reasonable, good faith approximation of the amount by which Parent Net Cash will exceed the Cash Dividend Amount, provided, that if the Closing Parent Net Cash is greater than $7,000,000, the Cash Dividend Amount shall not exceed (x) $4,500,000 plus (y) an amount equal to (A) 0.5 multiplied by (B) the Closing Parent Net Cash in excess of $7,000,000. There is no guarantee that the Parent Net Cash will exceed $2,500,000. The amount of the Cash Dividend is currently uncertain, pending the determination of our outstanding obligations and net cash position as of the Closing. Other than such potential special cash dividend in connection with the Closing, we do not currently anticipate declaring or paying cash dividends on its capital stock in the foreseeable future.

We may be at risk of securities class action litigation.

We may be at risk of securities class action litigation. This risk is especially relevant due to our dependence on positive clinical trial outcomes and regulatory approvals. In the past, biotechnology and pharmaceutical companies have experienced significant stock price volatility, particularly when associated with binary events such as clinical trials and product approvals. If we face such litigation, it could result in substantial costs and a diversion of management’s attention and resources, which could harm our business and result in a decline in the market price of our common stock.

In the event that we fail to satisfy any of the listing requirements of Nasdaq, our common stock may be delisted, which could affect our market price and liquidity.

Our common stock is listed on Nasdaq. For continued listing on Nasdaq, we will be required to comply with the continued listing requirements, including the minimum market capitalization standard, the minimum stockholders’ equity requirement, the corporate governance requirements and the minimum closing bid price requirement, among other requirements. In the event that we fail to satisfy any of the listing requirements of Nasdaq, our common stock may be delisted. If our securities are delisted from trading on the Nasdaq Stock Market, and we are not able to list our securities on another exchange or to have them quoted on the Nasdaq Stock Market, our securities could be quoted on the OTC Markets. As a result, we could face significant adverse consequences including:

We may issue additional equity securities in the future, which could result in dilution to existing investors.

We may seek the additional capital necessary to fund our operations through public or private equity offerings, debt financings, and collaborative and licensing arrangements. To the extent we raise additional capital by issuing equity securities, including in a debt financing where we issue convertible notes or notes with warrants and any shares of our common stock to be issued in a private placement, our stockholders may experience substantial dilution. We may, from time to time, sell additional equity securities in one or more transactions at prices and in a manner we determine. If we sell additional equity securities, existing stockholders may be materially diluted. In addition, new investors could gain rights superior to existing stockholders, such as liquidation and other preferences. In addition, the exercise or conversion of outstanding options or warrants to purchase shares of capital stock may result in dilution to our stockholders upon any such exercise or conversion.

In addition, as of March 17, 2025, 963,666 shares remained available to be awarded under our Amended and Restated 2013 Employee, Director and Consultant Equity Incentive Plan (the “Incentive Plan”). Further, an aggregate of 34,046 shares of our common stock could be delivered upon the exercise or conversion of outstanding stock options or restricted stock units under the Incentive Plan and other equity incentive plans we previously assumed. We may also issue additional options, warrants and other types of equity in the future as part of stock-based compensation, capital raising transactions, technology licenses, financings, strategic licenses or other strategic transactions. To the extent these options are exercised, existing stockholders would experience additional ownership dilution. In addition, the number of shares available for future grant under our equity compensation plans may be increased in the future, as our equity compensation plan contains an “evergreen” provision, pursuant to which additional shares may be authorized for issuance under the plan each year.

We currently take advantage of reduced disclosure and governance requirements applicable to smaller reporting companies, which could result in our common stock being less attractive to investors.

We have a public float of less than $250 million and therefore qualify as a smaller reporting company under the rules of the SEC. As a smaller reporting company, we are able to take advantage of reduced disclosure requirements, such as simplified executive compensation disclosures and reduced financial statement disclosure requirements in our SEC filings. Decreased disclosures in our SEC filings due to our status as a smaller reporting company may make it harder for investors to analyze our results of operations and financial prospects. We cannot predict if investors will find our common stock less attractive if we rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile. We may take advantage of the reporting exemptions applicable to a smaller reporting company until we are no longer a smaller reporting company, which status would end once we have a public float greater than $250 million. In that event, we could still be a smaller reporting company if our annual revenues were below $100 million and we have a public float of less than $700 million.

Anti-takeover provisions under Delaware corporate law may make it difficult for our stockholders to replace or remove our board of directors and could deter or delay third parties from acquiring us, which may be beneficial to our stockholders.

We are subject to the anti-takeover provisions of Delaware law, including Section 203 of the General Corporation Law of Delaware (the “DGCL”). Under these provisions, if anyone becomes an “interested stockholder,” we may not enter into a “business combination” with that person for three (3) years without special approval, which could discourage a third party from making a takeover offer and could delay or prevent a change of control. For purposes of Section 203 of the DGCL, “interested stockholder” means, generally, someone owning fifteen percent (15%) or more of our outstanding voting stock or an affiliate that owned fifteen percent (15%) or more of our outstanding voting stock during the past three (3) years, subject to certain exceptions as described in Section 203 of the DGCL.

Protective provisions in our charter and bylaws could prevent a takeover which could harm our stockholders.

Our certificate of incorporation and bylaws contain a number of provisions that could impede a takeover or prevent us from being acquired, including, but not limited to, a classified board of directors and limitations on the ability of our stockholders to remove a director from office without cause. Each of these charter and bylaw provisions give our board of directors the ability to render more difficult or costly the completion of a takeover transaction that our stockholders might view as being in their best interests.

None.

 CYBERSECURITY

We operate in the biopharmaceutical industry, which is subject to various cybersecurity risks that could adversely affect our business, financial condition, and results of operations, including intellectual property theft, fraud, extortion, harm to employees or customers, violation of privacy laws and other litigation and legal risk, and reputational risk. We recognize the critical importance of developing, implementing, and maintaining robust cybersecurity measures to safeguard our information systems and protect the confidentiality, integrity, and availability of our data. We currently have security measures in place to protect information and prevent data loss and other security breaches, including a cybersecurity risk assessment program. Both management and the board of directors are actively involved in the continuous assessment of risks from cybersecurity threats, including prevention, mitigation, detection, and remediation of cybersecurity incidents.

We are a virtual company and do not lease or own any physical space. We maintain a mailing address at 945 Concord Street, Suite 1217, Framingham, Massachusetts 01701.

We assigned our previous lease, for our previous headquarters in Bedford, Massachusetts, during the third quarter of 2024 to MannKind Corporation.

From time to time, we may be involved in litigation that arises through the normal course of business. As of the date of this filing, we are not aware of any material legal proceedings to which we or our subsidiaries are a party or to which any of our property is subject, nor are we aware of any such threatened or pending litigation or proceedings known to be contemplated by governmental authorities.

There are no material proceedings in which any of our directors, officers or affiliates or any registered or beneficial stockholder of more than 5% of our common stock, or any associate of any of the foregoing, is an adverse party or has a material interest adverse to our interest.

Not applicable.

PART II

Market Information

Our common stock trades on The Nasdaq Capital Market under the symbol “PULM”.

Stockholders

As of March 17, 2025, there were approximately 43 stockholders of record of our common stock.

Dividends

We have not paid dividends to our stockholders since inception. Pursuant to the terms of the Merger Agreement, Pulmatrix may declare and pay a special cash dividend to Pulmatrix stockholders of record prior to the Merger. The Cash Dividend will be up to an amount equal in the aggregate to Pulmatrix’s reasonable, good faith approximation of the amount by which Pulmatrix’s Net Cash will exceed the Cash Dividend Amount, provided, that if the Closing Pulmatrix Net Cash is greater than $7,000,000, the Cash Dividend Amount shall not exceed (x) $4,500,000 plus (y) an amount equal to (A) 0.5 multiplied by (B) the Closing Pulmatrix Net Cash in excess of $7,000,000. There is no guarantee that the Pulmatrix Net Cash will exceed $2,500,000. The amount of the Cash Dividend is currently uncertain, pending the determination of Pulmatrix’s outstanding obligations and net cash position as of the Closing. Other than such potential special cash dividend in connection with the Closing, Pulmatrix does not currently anticipate declaring or paying cash dividends on its capital stock in the foreseeable future.

Unregistered Sales of Securities

None.

Issuer Purchases of Equity Securities

Not applicable.

The information set forth below should be read in conjunction with our consolidated financial statements and related notes thereto included elsewhere in this Annual Report on Form 10-K. This discussion and analysis contain forward-looking statements based on our current expectations, assumptions, estimates and projections. These forward-looking statements involve risks and uncertainties. Our actual results could differ materially from those indicated in these forward-looking statements as a result of certain factors, including those discussed in Item 1 of this Annual Report on Form 10-K, entitled “Business,” under “Forward-Looking Statements” and Item 1A of this Annual Report on Form 10-K, entitled “Risk Factors.” References in this discussion and analysis to “us,” “we,” “our,” or our “Company” refer to Pulmatrix, Inc., a Delaware corporation, and our subsidiaries, Pulmatrix Operating Company, Inc. and PCL Merger Sub, Inc., both Delaware corporations, and PCL Merger Sub II, LLC, a Delaware limited liability company.

Overview

We are a biopharmaceutical company that has focused on the development of novel inhaled therapeutic products intended to prevent and treat migraine and respiratory diseases with important unmet medical needs using our patented iSPERSE^™ technology. Our proprietary product pipeline includes treatments for central nervous system (“CNS”) disorders such as acute migraine and serious lung diseases such as Chronic Obstructive Pulmonary Disease (“COPD”) and allergic bronchopulmonary aspergillosis (“ABPA”). Our product candidates are based on our proprietary engineered dry powder delivery platform, iSPERSE^™, which seeks to improve therapeutic delivery to the lungs by optimizing pharmacokinetics and reducing systemic side effects to improve patient outcomes.

We design and develop inhaled therapeutic products based on our proprietary dry powder delivery technology, iSPERSE^™, which enables delivery of small or large molecule drugs to the lungs by inhalation for local or systemic applications. The iSPERSE^™ powders are engineered to be small, dense particles with highly efficient dispersibility and delivery to airways. iSPERSE^™ powders can be used with an array of dry powder inhaler technologies and can be formulated with a broad range of drug substances including small molecules and biologics. We believe the iSPERSE^™ dry powder technology offers enhanced drug loading and delivery efficiency that outperforms traditional lactose-blend inhaled dry powder therapies.

We believe the advantages of using the iSPERSE^™ technology include reduced total inhaled powder mass, enhanced dosing efficiency, reduced cost of goods, and improved safety and tolerability profiles.

After a comprehensive review of strategic alternatives, including identifying and reviewing potential candidates for a strategic transaction, on November 13, 2024, we entered into an Agreement and Plan of Merger and Reorganization (the “Merger Agreement”), by and among Pulmatrix, PCL Merger Sub, Inc., a Delaware corporation and our wholly owned subsidiary of (“Merger Sub I”), PCL Merger Sub II, LLC, a Delaware limited liability company and our wholly owned subsidiary (“Merger Sub II” and together with Merger Sub I, “Merger Subs”) and Cullgen Inc., a Delaware corporation (“Cullgen”), pursuant to which, and subject to the satisfaction or waiver of the conditions set forth in the Merger Agreement, among other things, Merger Sub I will merge with and into Cullgen, with Cullgen surviving the merger as the surviving corporation (the “First Merger”) and as part of the same overall transaction, Cullgen will merge with and into Merger Sub II, with Merger Sub II continuing as wholly owned subsidiary and the surviving corporation of the merger (the “Second Merger” and together with the First Merger, the “Merger”). The Merger Agreement was unanimously approved by our board of directors (the “Board” or “board of directors”), which resolved to recommend approval of the Merger Agreement to our stockholders.

The closing of the Merger is subject to approval by our stockholders and Cullgen stockholders, as well as other customary closing conditions, including the effectiveness of a registration statement filed with the SEC in connection with the transaction, Nasdaq’s approval of the listing of the shares of our common stock to be issued in connection with the Merger, and approval from the China Security Regulatory Commission. If the Merger is completed, the business of Cullgen will continue as the business of the combined company. We are currently seeking opportunities to monetize our existing clinical assets.

Our future operations are highly dependent on the success of the Merger and there can be no assurances that the Merger will be successfully consummated. There can be no assurance that the strategic review process or any transaction relating to a specific asset, including the Merger and any asset sale, will result in the Company pursuing such a transaction, or that any transactions, if pursued, will be completed on terms favorable to the Company and its stockholders in the existing Pulmatrix entity or any possible entity that results from a combination of entities. If the strategic review process is unsuccessful, and if the Merger is not consummated, the Pulmatrix board of directors may decide to pursue a dissolution and liquidation of the Company.

Our goal has been to develop breakthrough therapeutic products that are safe, convenient, and more effective than the existing therapeutic products for respiratory and other diseases where iSPERSE^™ properties are advantageous.

Our current pipeline of clinical assets is aligned to this goal and includes iSPERSE^™-based therapeutic candidates which target the prevention and treatment of a range of diseases, including CNS disorders and pulmonary diseases. These therapeutic candidates include PUR3100 for the treatment of acute migraine, PUR1800 for the treatment of acute exacerbations of chronic obstructive pulmonary disease (“AECOPD”), and PUR1900 for the treatment of ABPA in patients with asthma and in patients with cystic fibrosis (“CF”). Each program is enabled by its unique iSPERSE^™ formulation designed to achieve specific therapeutic objectives.

We are exploring opportunities to monetize these clinical assets in connection with the Merger. Continued development of these candidates, if that were to occur, would be contingent on securing additional funding and would require significant expenditures to advance. Thereafter, if development of such product candidates were to be continued and successfully advanced (of which there can be no assurance), it would be necessary to seek and obtain marketing approval to commercialize such product candidates, which could be expected to require the expenditure of significant additional resources and expenses related to regulatory, product sales, medical affairs, marketing, manufacturing and distribution.

Contingent on securing additional funding and continuing development of these candidates, we would expect to continue to incur substantial expenses and operating losses for at least the next several years, as we would:

We do not have any products approved for sale and have not generated any revenue from product sales. We will not generate product sales unless and until we successfully complete clinical developments and obtain regulatory approvals for our product candidates. Additionally, we currently utilize third-party contract research organizations (“CROs”) to carry out our clinical development activities and third-party contract manufacturing organizations (“CMOs”) to carry out our clinical manufacturing activities as we do not yet have a commercial organization. If we obtain regulatory approval for any of our product candidates, we expect to incur substantial expenses related to developing our internal commercialization capability to support product sales, marketing and distribution. Accordingly, we anticipate that we will seek to fund our operations through public or private equity or debt financings, licensing arrangements, collaborations with third parties, non-dilutive grants or other sources, potentially including collaborative commercial arrangements. Likewise, we intend to seek to limit our commercialization costs by partnering with other companies with complementary capabilities or larger infrastructure including sales and marketing.

Because of the numerous risks and uncertainties associated with product development, we are unable to predict the timing or amount of increased expenses or when or if we will be able to achieve or maintain profitability. Even if we are able to generate product sales, we may not become profitable. If we fail to become profitable or are unable to sustain profitability on a continuing basis, we may be unable to continue our operations at planned levels and be forced to reduce or terminate our operations.

Therapeutic Candidates

PUR3100

We are currently exploring opportunities to monetize PUR3100.

In 2020, we developed PUR3100, the iSPERSE^™ formulation of DHE, for the treatment of acute migraine. Currently DHE is only available as subcutaneous, intravenous infusion or intranasal delivery. If approved for commercialization, PUR3100 has the opportunity to be the first orally inhaled DHE treatment for acute migraine and be an alternative to other acute therapies. Given the oral inhaled route of delivery, PUR3100 is anticipated to provide relief from the rapid onset of migraine symptoms and provide a favorable tolerability profile.

A total of three 14-day GLP toxicology studies have been completed with PUR3100 to support single-dose clinical studies. We are planning to conduct a chronic toxicology study to support long-term dosing. Based on discussions with the FDA, this would complete the non-clinical requirements to support an NDA.

Our interactions with the FDA have indicated that, in addition to the planned Phase 2 and Phase 3 studies, long-term safety should be assessed in a minimum of one hundred patients for six months of dosing and fifty patients for twelve months of dosing. The FDA also confirmed that it will be necessary to perform a safety study administering PUR3100 to otherwise healthy patients with asthma before an NDA is submitted.

On September 26, 2022, we announced the completion of patient dosing in a Phase 1 clinical study, performed in Australia. The study design was a double-dummy, double-blinded trial to assess the safety, tolerability, and pharmacokinetics of three dose levels of single doses of inhaled PUR3100 with IV placebo, as compared to IV DHE (DHE mesylate injection) with inhaled placebo. This study may also provide preliminary comparative bioavailability data to support the use of the 505(b)(2) pathway for marketing authorization. Twenty-six healthy subjects were enrolled and each of the four groups contained at least six subjects.

On January 4, 2023, we announced topline results. We presented the Phase 1 study data at the American Headache Society 65th Annual Meeting in June 2023. The study showed that PUR3100 achieved peak exposures in the targeted therapeutic range and time to maximum concentration occurred at five minutes after dosing at all dosing levels. The PUR3100 dose groups also showed a lower incidence of nausea and no vomiting compared to observations of nausea and vomiting in the IV administered DHE dose group.

Based on the rapid systemic exposure in the therapeutic range and the improved side effect profile relative to IV dosing, we believe the PUR3100 formulation of DHE may differentiate from approved DHE products or those known to be in development. If effectiveness is demonstrated, PUR3100 may offer the convenience of being self-administered with a pharmacokinetic profile that may potentially provide rapid onset of action.

In September 2023, we announced that the FDA accepted the PUR3100 IND and the receipt of a “study may proceed” letter for the clinical study: “A Phase 2, Multicenter, Randomized, Double-Blind, Placebo-Controlled, Single Event Study to Evaluate the Safety, Tolerability, and Efficacy of PUR3100 (Dihydroergotamine Mesylate Inhalation Powder) in the Acute Treatment of Migraine”. We anticipate that this Phase 2 clinical study will initiate once financing or partnership arrangements have been made.

On May 15, 2024, we announced publication of, “Safety, tolerability, and pharmacokinetics of a single orally inhaled dose of PUR3100, a dry powder formulation of dihydroergotamine versus intravenous dihydroergotamine: A Phase 1 randomized, double-blind study in healthy adults” in the peer-reviewed publication Headache: The Journal of Head and Face Pain.

We believe that in this trial, PUR3100 demonstrated the potential for rapid pain relief and improved DHE tolerability versus IV DHE. With a T_max of 5 minutes and a C_max in the therapeutic window for all doses tested, we believe that PUR3100 has the potential to address an unmet need for acute migraine sufferers and we are pursuing different options to advance PUR3100 into a Phase 2 clinical trial to further investigate its promising profile in treating acute migraine.

The completed Phase 1 study demonstrated optimal pharmacokinetics and improved tolerability of PUR3100 compared to IV DHE. The Phase 1 trial was a randomized, double-dummy, double-blinded design to assesses the safety, tolerability, and pharmacokinetics (PK) of three dose groups treated with inhaled PUR3100 with intravenous (IV) placebo, compared to a single dose of IV DHE (DHE mesylate injection) with inhaled placebo in healthy volunteers. All doses of PUR3100 were generally well tolerated with a lower incidence of nausea (21% vs. 86%), vomiting (0% vs. 29%), and headache (16% vs. 57%) compared to IV DHE. The PK profile of PUR3100 versus IV DHE was characterized by a similar mean time to C_max (5 vs. 5.5 min), with reduced AUC0–2h (1120–4320 vs. 6340), and a lower C_max (3620–14,400 vs. 45,000). All doses of PUR3100 were associated with mean C_max above the minimum level required to achieve efficacy (1000 pg/mL).

PUR1800

We are currently exploring opportunities to monetize PUR1800.

PUR1800 is a Narrow Spectrum Kinase Inhibitor, engineered with our iSPERSE^™ technology, being developed for the treatment of acute exacerbations in chronic obstructive pulmonary disease (AECOPD). PUR1800 targets p38 MAP kinases (p38MAPK), Src kinases, and Syk kinases. These kinases play a critical role in chronic inflammation and airway remodeling.

We completed a Phase 1b safety, tolerability, and pharmacokinetics of PUR1800 for patients with stable moderate-severe COPD. Topline data was delivered in the first quarter of 2022 and presented at the American Academy of Allergy, Asthma and Immunology conference in the first quarter of 2023.

The clinical study, performed at the Medicines Evaluation Unit in Manchester, UK, was a randomized, three-way crossover double-blind study with 14 days of daily dosing, which included placebo and one of two doses of PUR1800, and included a 28-day follow-up period after each treatment period. A total of 18 adults with stable COPD were enrolled. Safety and tolerability, as well as systemic pharmacokinetics (“PK”) were evaluated.

PUR1800 was well tolerated and there were no observed safety signals. The PK data indicate that PUR1800 results in low and consistent systemic exposure when administered via oral inhalation. The topline data, along with the results from chronic toxicology studies, support the continued development of PUR1800 for the treatment of AECOPD and other inflammatory respiratory diseases. These data will inform the design of a potential Phase 2 study in the treatment of AECOPD.

Toxicology studies in rats and dogs, with durations of six and nine months respectively, are complete. The data from both studies demonstrated that PUR1800 is safe and well tolerated with chronic dosing, with little to no progression of findings from 28-day studies. We believe that this indicates potential for chronic dosing of PUR1800, enabling us to explore PUR1800 therapy for chronic respiratory diseases such as steroid resistant asthma, COPD, or idiopathic pulmonary fibrosis. While the program is currently in development for treatment of acute exacerbation of COPD, these positive toxicology study results could expand potential indications and value of the program.

PUR1900

We are currently exploring opportunities to monetize PUR1900 within the United States.

On April 15, 2019, we entered into a Development and Commercialization Agreement (the “Cipla Agreement”) with Cipla for the co-development and commercialization, on a worldwide, except for the Cipla Territory defined below, exclusive basis, of PUR1900, our inhaled iSPERSE^™ drug delivery system (the “Product”) enabled formulation of the antifungal drug itraconazole, which is only available as an oral drug, for the treatment of all pulmonary indications, including ABPA in patients with asthma. We entered into an amendment to the Cipla Agreement on November 8, 2021 (the “Second Amendment”) and a subsequent amendment on January 6, 2024 (the “Third Amendment”). All references to the Cipla Agreement herein refer to the Cipla Agreement, as amended. The Cipla Agreement will remain in effect in perpetuity, unless otherwise earlier terminated in accordance with its terms.

Pursuant to the Third Amendment, all development and commercialization activities with respect to the Product in all markets other than the United States (the “Cipla Territory”) will be conducted exclusively by Cipla at Cipla’s sole cost and expense, and Cipla shall be entitled to all profits from the sale of the Product in the Cipla Territory, except that we will receive 2% royalties on any potential future net sales by Cipla outside the United States.

Also pursuant to the Third Amendment, we and Cipla stopped patient enrollment for the ongoing Phase 2b clinical study. We agreed that during the period commencing on January 6, 2024 and ending July 30, 2024 (the “Wind Down Period”), we would complete all Phase 2b activities, assign or license all patents to Cipla and their registration with the appropriate authorities in the Cipla Territory, complete a physical and demonstrable technology transfer and secure all data from the Phase 2b study for inclusion in the safety database for the Cipla Territory.

For the duration of the Wind Down Period, we and Cipla were each responsible for 60% and 40%, respectively, of our Direct Costs. We shared all other development costs with Cipla that are not Direct Costs, such as the cost of clinical research organizations, manufacturing costs and other third-party costs, on a 50/50 basis. Reimbursements from Cipla to us for these costs were subject to a maximum reimbursement amount as approved by the joint steering committee.

We completed all Phase 2b wind down activities in the third quarter of 2024. As such, we no longer bear further financial responsibility for the commercialization and development with respect to the Product in the Cipla Territory, with such commercialization and development expenses of the Product in the Cipla Territory to be borne at Cipla’s sole cost and expense after January 6, 2024. We will receive 2% royalties on any potential future net sales by Cipla outside the United States. Within the United States, we and Cipla will seek to monetize PUR1900, our inhaled iSPERSE^™ formulation of the antifungal drug itraconazole for indications where an orally inhaled antifungal may provide a therapeutic benefit or fulfill an unmet medical need.

Financial Overview

Revenues

To date, we have not generated any product sales. Revenues for the years ended December 31, 2024 and 2023 were primarily generated from the Cipla Agreement as related to our PUR1900 program, for which wind down activities have been completed.

For more discussion on the Cipla Agreement, please see Note 6, Significant Agreements, to our consolidated financial statements included in this report.

Research and Development Expenses

Research and development expenses consist primarily of costs incurred for the research and development of our preclinical and clinical candidates, and include:

We expense research and development costs to operations as incurred. We recognize costs for certain development activities, such as clinical trials, based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations or information provided to us by our vendors.

Research and development activities are central to our business model. We have utilized a combination of internal and external efforts to advance product development from early-stage work to clinical trial manufacturing and clinical trial support. External efforts have included work with consultants and substantial work at CROs and CMOs. We have historically supported an internal research and development team and facility for our pipeline and other potential development programs, however following the closing of the MannKind Transaction in the third quarter of 2024, in which the majority of our research and development employees were terminated and our facility lease was assigned to MannKind, we expect to utilize external resources for further development.

To continue development of existing programs or opportunities identified for iSPERSE^™ in any new indications, we will need to secure additional funding and anticipate additional development costs would be incurred. Because of the numerous risks and uncertainties associated with product development, however, we cannot determine with certainty the duration and completion costs of these or other current or future preclinical studies and clinical trials. The duration, costs and timing of our future clinical trials and development of our product candidates will depend on a variety of factors, including the selected development path and uncertainties associated with clinical and preclinical studies, clinical trial enrollment rates and changing government regulation. In addition, the probability of success for each product candidate will depend on numerous factors, including competition, manufacturing capability and commercial viability.

General and Administrative Expenses

General and administrative expenses consist principally of salaries, benefits and related costs such as stock-based compensation for personnel and consultants in executive, finance, business development, corporate communications and human resource functions, facility costs not otherwise included in research and development expenses, patent filing fees and legal fees. Other general and administrative expenses include travel expenses, expenses related to being a publicly traded company, professional fees for consulting, auditing and tax services, and expenses related to the Company’s exploration of strategic alternatives, including the Merger.

Critical Accounting Estimates

Our management’s discussion and analysis of our financial condition and results of operations is based on our consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). The preparation of our consolidated financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities in our consolidated financial statements. We base our estimates on historical experience, known trends and events, and other assumptions that we believe are reasonable under the circumstances, and we evaluate these estimates on an ongoing basis. Actual results may differ from these estimates under different assumptions or conditions.

Our significant accounting policies are described in the notes to our consolidated financial statements appearing elsewhere in this Annual Report on Form 10-K. We believe the following are our critical accounting estimates which involve a significant level of uncertainty at the time the estimate was made, and changes in them have had or are reasonably likely to have a material effect on our financial condition or results of operations.

Revenue Recognition

Our principal source of revenue during the years ended December 31, 2024 and 2023 was derived from the Cipla Agreement. Revenue is recognized for the Cipla Agreement over the period of performance using a measure of progress based on costs incurred to date relative to the total expected costs (i.e., cost-to-cost method). Prior to the completion of the wind down of the Phase 2b study for PUR1900, a significant level of judgment has been necessary to estimate the total expected costs. The amount of revenue recognized in a given period is dependent on the accuracy of our estimate of the total expected costs. When estimating total expected costs, we make assumptions and estimates regarding the total amount of internal and external resources required to satisfy the performance obligation, including the contracted scope of work with Cipla and tasks required to be completed, along with our ability and that of our contracted third parties to successfully carry out expected duties, achieve certain regulatory requirements and meet expected deadlines. We evaluate our measure of progress to recognize revenue for these agreements at each reporting date and, as necessary, adjust the measure of progress and related revenue recognition. We also evaluate contract modifications and amendments to determine whether any changes should be accounted for prospectively or on a cumulative catch-up basis.

Accrued Research and Development Costs

We have various contracts with third parties related to our research and development activities. Research and development costs are expensed as incurred. Costs that are incurred but not billed to us as of the end of the period are accrued. Prior to the completion of the wind down of the Phase 2b study for PUR1900, estimating the expense incurred with CROs and CMOs involved significant uncertainty because these service providers may invoice us several months in arrears, on a pre-determined schedule or when contractual milestones are met; however, some require advance payments. We make estimates of the expense incurred in each period based on the information available to us, our knowledge of the nature of the contractual activities generating such costs and communications with the service providers. Although we do not expect our estimates to be materially different from amounts actually incurred, such estimates for the status and timing of services performed relative to the actual status and timing of services performed may vary and could result in us reporting amounts that are too high or too low in any particular period. To date, our estimates have not been materially different than amounts actually incurred.

Results of Operations

Comparison of the Years Ended December 31, 2024 and 2023

The following table sets forth our results of operations for each of the periods set forth below (in thousands):