Form 8-K

8-K — X4 Pharmaceuticals, Inc

Accession: 0001501697-26-000060

Filed: 2026-07-01

Period: 2026-06-30

CIK: 0001501697

SIC: 2836 (BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES))

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — xfor-20260630.htm (Primary)

EX-99.1 (exhibit991_pressreleasedat.htm)

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8-K

8-K (Primary)

Filename: xfor-20260630.htm · Sequence: 1

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 30, 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)

(857) 529-8300

(Registrant’s telephone number, including area code)

Not applicable

(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.

Emerging growth company ☐

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. ☐

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On June 30, 2026, of X4 Pharmaceuticals, Inc. (the “Company”) appointed Kelly Gold as a Class II director of the Company, effective as of July 1, 2026. In connection with Ms. Gold’s appointment, the size of the Company’s board of directors (the “Board”) was increased from five to six directors. Ms. Gold has also been appointed to serve on the Audit Committee of the Board.

Ms. Gold, age 49, has served as Chief Financial Officer of CAMP4 Therapeutics Corporation, a clinical-stage biopharmaceutical company (Nasdaq: CAMP), since April 2022. Ms. Gold previously served as CAMP4’s Chief Business Officer from April 2021 to March 2022, and held positions of increasing responsibility in Finance and Corporate Development at CAMP4 from 2017 to March 2021. Ms. Gold previously served as Associate Director, Strategic Corporate Finance at Biogen Inc. (Nasdaq: BIIB) from 2014 to 2017, where she provided financial leadership for the company’s late stage and marketed rare disease programs and developed long term strategic financial trajectories for the R&D organization. Ms. Gold also previously served as a Healthcare Investment Banking Associate at Deutsche Bank from 2009 to 2013, where she worked in the healthcare investment banking group. Ms. Gold earned bachelor’s degrees in Life Sciences and Mechanical Engineering from Queen’s University in Ontario and an MBA from the MIT Sloan School of Management.

In connection with her appointment to the Board, Ms. Gold will be entitled to receive compensation in accordance with the Company’s non-employee director compensation policy as generally described in the Company’s Definitive Proxy Statement filed on March 20, 2026. Ms. Gold is also entering into the Company’s standard form of indemnification agreement, a form of which was previously filed as Exhibit 10.36 to Amendment No. 1 to the Company’s Registration Statement on Form S-1 filed on November 6, 2017.

There are no arrangements or understandings between Ms. Gold and any other person pursuant to which she was appointed as director of the Company; there are no family relationships between Ms. Gold and any director or executive officer of the Company; and Ms. Gold is not a party to any transactions of the type that would require disclosure under Item 404(a) of Regulation S-K.

Item 7.01 Regulation FD Disclosure.

A copy of the Company’s press release announcing the foregoing appointment is furnished hereto as Exhibit 99.1.

The information in this Item 7.01 (including Exhibit 99.1) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 9.01. Financial Statements and Exhibits.

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

Exhibit Number Exhibit Title or Description

99.1

Press Release, dated July 1, 2026

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

SIGNATURE

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: July 1, 2026 Chief Financial Officer and Treasurer

EX-99.1

Filename: exhibit991_pressreleasedat.htm · Sequence: 2

Document

Exhibit 99.1

X4 Pharmaceuticals Appoints Kelly Gold, Experienced Chief Financial Officer, to its Board of Directors

BOSTON, July 1, 2026 – X4 Pharmaceuticals (Nasdaq: XFOR), a company focused on improving the lives of people with rare hematology diseases, today announced the appointment of Kelly Gold to the Company’s Board of Directors effective July 1, 2026, adding strong strategic and financial expertise. Ms. Gold will serve as an independent director and member of the Audit Committee.

“We are thrilled to welcome Kelly to our Board of Directors as she brings a distinct combination of financial leadership, capital markets expertise and a scientific background,” said Adam Craig, M.D., Ph.D., Executive Chairman of X4 Pharmaceuticals. “As we continue to strengthen our team to align with our strategic priorities, Kelly’s experience as a public company CFO, coupled with her deep understanding of the biotech landscape will be a great addition to our Board. We look forward to leveraging her experience as we continue to progress mavorixafor towards potential approval and commercialization.”

"I am honored to join X4 Pharmaceuticals’ Board at this important stage in the company's evolution. X4 has built a strong foundation through its commitment to developing innovative therapies for patients living with rare diseases, and I look forward to working alongside my fellow directors and the leadership team as the company advances its mission," added Ms. Gold.

Ms. Gold is currently the Chief Financial Officer at CAMP4 Therapeutics (Nasdaq: CAMP) where she has held roles of increasing responsibility leading the Business Development and Finance functions before becoming CFO. At CAMP4, she leads all corporate finance and accounting, investor relations, strategic financial planning, and is responsible for guiding and executing the company’s strategy for establishing innovative strategic and technology-based partnerships. Previously, Ms. Gold held various roles in corporate finance and business planning at Biogen, where she provided financial leadership for the company’s late stage and marketed rare disease programs and developed long-term strategic financial trajectories for the R&D organization. Prior to Biogen, Ms. Gold worked in the Healthcare and Latin American Investment Banking groups at Deutsche Bank. Ms. Gold began her career as a mechanical engineer designing biocontainment systems for Biosafety Level 4 research facilities. She holds bachelor’s degrees in

Biochemistry and Mechanical Engineering from Queen’s University in Ontario, as well as an MBA from the MIT Sloan School of Management.

About X4 Pharmaceuticals

X4 Pharmaceuticals is a company focused on improving the lives of people with rare hematology diseases by developing and commercializing innovative therapies in areas with significant unmet needs. Leveraging expertise in diseases of the immune system and CXCR4 biology, X4 has successfully developed mavorixafor, an orally available CXCR4 antagonist that is approved in the U.S. and EU as XOLREMDI® for patients with WHIM syndrome. The Company is currently conducting a global, pivotal Phase 3 clinical trial (4WARD) evaluating mavorixafor in chronic neutropenic disorders. The U.S. FDA has granted Fast Track designation to mavorixafor for the treatment of chronic neutropenia. X4 is headquartered in Boston, Massachusetts. For more information, please visit www.x4pharma.com.

X4 Investor Contact:

Remy Bernarda

Jenny Kobin

IR Advisory Solutions

ir@x4pharma.com

Source: X4 Pharmaceuticals, Inc.

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X4 PHARMACEUTICALS, INC.

Entity Incorporation, State or Country Code

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001-38295

Entity Tax Identification Number

27-3181608

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