SEC Form SC 13G/A filed by X4 Pharmaceuticals Inc. (Amendment)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 4)*

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

o Rule 13d-1(b)

x Rule 13d-1(c)

o Rule 13d-1(d)

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

X4 Pharmaceuticals, Inc.

61 North Beacon Street, 4th Floor

Boston, Massachusetts 02134

OrbiMed Advisors LLC

OrbiMed Capital GP IV LLC

601 Lexington Avenue, 54th Floor

New York, NY 10022

Please refer to Item 4 on each cover sheet for each filing person.

Common Stock, par value $0.001 per share

         98420X103

Item 3.

OrbiMed Capital GP IV LLC (“GP IV”) is the general partner of OrbiMed Private Investments IV, LP. OrbiMed Advisors LLC (“Advisors”) is an investment advisor in accordance with ss.240.13d-1(b)(1)(ii)(E) and is the managing member of GP IV.

 Item 4. Ownership:

Information with respect the Reporting Persons’ ownership as of December 31, 2023 is incorporated by reference to items (5) – (9) and (11) of the cover page for the Reporting Person.

Item 5. Ownership of Five Percent or Less of a Class.

If this statement is being filed to report the fact that as of the date hereof the Reporting Person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following [ ].

Item 6. Ownership of More Than Five Percent on Behalf of Another Person.

The Reporting Persons are holding 6.7% of the shares of Common Stock in the aggregate on behalf of other persons who have the right to receive or the power to direct the receipt of dividends from, or proceeds from the sale of, such securities. Advisors exercises investment and voting power over the shares of Common Stock through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the shares of Common Stock reported herein.

Item 7. Identification and Classification of the Subsidiary which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not Applicable.

Item 8. Identification and Classification of Members of the Group.

Not Applicable.

Item 9. Notice of Dissolution of Group.

Not Applicable.

Item 10. Certification.

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a–11.

SIGNATURES

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: February 14, 2024