xfor-20260908

Date of Report (Date of earliest event reported): September 8, 2026



X4 PHARMACEUTICALS, INC.
(Exact name of registrant as specified in its charter)

Delaware

001-38295

27-3181608

(State or other jurisdiction of incorporation)

(Commission File Number)

(IRS Employer Identification No.)


61 North Beacon Street,	4th Floor
Boston,	Massachusetts	02134
(Address of principal executive offices)		(Zip Code)

(Registrant’s telephone number, including area code)

(Former name or former address, if changed since last report)

_______________________________________________________________________________________________________

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common stock, par value $0.001 per share

XFOR

The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 or Rule 12b-2 of the Securities Exchange Act of 1934.

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. ☐

On September 8, 2026, X4 Pharmaceuticals, Inc. (the “Company”) issued a press release announcing the positive outcome of the Company’s Type C Meeting with the U.S. Food and Drug Administration related to the global 4WARD Phase 3 clinical trial.

A copy of the press release is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated by reference herein.

(d) Exhibits. The following exhibits are being furnished herewith:


Exhibit Number						Exhibit Title or Description
99.1						Press Release, dated September 8, 2026

104						Cover Page Interactive Data File (embedded within the Inline XBRL document)

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.


	X4 PHARMACEUTICALS, INC.

	By:	/s/ David Kirske
		David Kirske
Date: September 8, 2026		Chief Financial Officer and Treasurer


FORM			8-K


Item 8.01.			Other Events.


Item 9.01.			Financial Statements and Exhibits.