13D Filings
X4 Pharmaceuticals, Inc.
XFOR
Amendment
Ownership

6.20%

Total Shares

5,057,610

Issuer CIK

1501697

CUSIP

98420X202

Event Date

Oct 26, 2025

Accepted

Oct 29, 2025, 06:04 PM

Reporting Persons (12)
Joint Filing

This is a joint filing. The reported shares may overlap between reporting persons and should not be summed.

NameType% of ClassAggregateSole VotingShared Voting
Growth Equity Opportunities 18 VGE, LLC
Other
6.20%5,057,61005,057,610
NEA 18 Venture Growth Equity, L.P.
Partnership
6.20%5,057,61005,057,610
NEA Partners 18 VGE, L.P.
Partnership
6.20%5,057,61005,057,610
NEA 18 VGE GP, LLC
Other
6.20%5,057,61005,057,610
Ali Behbahani
Individual
6.20%5,057,61005,057,610
Carmen Chang
Individual
6.20%5,057,61005,057,610
Anthony A. Florence, Jr.
Individual
6.20%5,057,61005,057,610
Mohamad H. Makhzoumi
Individual
6.20%5,057,61005,057,610
Edward T. Mathers
Individual
6.20%5,057,61005,057,610
Scott D. Sandell
Individual
6.20%5,057,61005,057,610
Paul Walker
Individual
6.20%5,057,61005,057,610
Rick Yang
Individual
6.20%5,057,61005,057,610
Disclosure Items (7)

Security Title

Common Stock, par value $0.001 per share

Issuer Name

X4 Pharmaceuticals, Inc.

Issuer Address

61 North Beacon Street, Boston, MA, 02134

Filing Persons

Growth Equity Opportunities 18 VGE, LLC ("GEO"); NEA 18 Venture Growth Equity, L.P. ("NEA 18 VGE"), which is the sole member of GEO; NEA Partners 18 VGE, L.P. ("NEA Partners 18 VGE"), which is the sole general partner of NEA 18 VGE; and NEA 18 VGE GP, LLC ("NEA 18 VGE LLC" and together with NEA Partners 18 VGE, the "Control Entities"), which is the sole general partner of NEA Partners 18 VGE; and Ali Behbahani ("Behbahani"), Carmen Chang ("Chang"), Anthony A. Florence, Jr. ("Florence"), Mohamad H. Makhzoumi ("Makhzoumi"), Edward T. Mathers ("Mathers"), Scott D. Sandell ("Sandell"), Paul Walker ("Walker") and Rick Yang ("Yang") (together, the "Managers"). The Managers are the managers of NEA 18 VGE LLC. The persons named in this Item 2 are referred to individually herein as a "Reporting Person" and collectively as the "Reporting Persons."

Business Address

The address of the principal business office of GEO, NEA 18 VGE, each Control Entity and Sandell is New Enterprise Associates, 1954 Greenspring Drive, Suite 600, Timonium, MD 21093. The address of the principal business office of Behbahani, Chang, Makhzoumi, Walker and Yang is New Enterprise Associates, 2855 Sand Hill Road, Menlo Park, CA 94025. The address of the principal business office of Florence and Mathers is New Enterprise Associates, 104 5th Avenue, 19th Floor, New York, NY 10011.

Principal Occupation

The principal business of GEO and NEA 18 VGE is to invest in and assist growth-oriented businesses located principally in the United States. The principal business of NEA Partners 18 VGE is to act as the sole general partner of NEA 18 VGE. The principal business of NEA 18 VGE LLC is to act as the sole general partner of NEA Partners 18 VGE. The principal business of each of the Managers is to manage the Control Entities, GEO and a number of affiliated partnerships with similar businesses.

Convictions

During the five years prior to the date hereof, none of the Reporting Persons has been convicted in a criminal proceeding or has been a party to a civil proceeding ending in a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

Citizenship

GEO and NEA 18 VGE LLC are limited liability companies organized under the laws of the State of Delaware. NEA 18 VGE and NEA Partners 18 VGE are limited partnerships organized under the laws of the State of Delaware. Each of the Managers is a United States citizen.

Item 3 is hereby amended to add the following: On October 27, 2025, the Issuer completed the closing of an underwritten offering (the "Offering") of (i) 52,844,000 shares of Common Stock and (ii) pre-funded warrants to purchase 700,000 shares of Common Stock. In connection with the Offering, GEO purchased 1,000,000 shares of Common Stock at a purchase price of $2.90 per share. GEO now owns a total of 3,233,744 shares of Common Stock and a right, upon exercise of the 2025 GEO Pre-Funded Warrants, the Pre-Funded Warrants, GEO Class C Warrants and/or the GEO Warrants and taking into account their respective beneficial ownership limitations, to purchase up to 1,823,866 shares of Common Stock (the "Exercisable Shares") for a total deemed ownership of 5,057,610 shares of Common Stock (the "GEO Shares"). The working capital of GEO is the source of the funds for the purchase of the GEO Shares. No part of the purchase price of the GEO Shares is represented by funds or other consideration borrowed or otherwise obtained for the purpose of acquiring, holding, trading or voting the GEO Shares.

GEO acquired the GEO Shares for investment purposes. Information with respect to the Offering set forth in Item 3 above is incorporated herein by reference to the extent responsive to this Item 4. Subject to the foregoing, depending on market conditions, its continuing evaluation of the business and prospects of the Issuer and other factors, GEO and other Reporting Persons may dispose of or acquire additional shares of the Issuer. Except as set forth above, none of the Reporting Persons has any present plans which relate to or would result in: (a) The acquisition by any person of additional securities of the Issuer, or the disposition of securities of the Issuer; (b) An extraordinary corporate transaction, such as a merger, reorganization or liquidation, involving the Issuer or any of its subsidiaries; (c) A sale or transfer of a material amount of assets of the Issuer or any of its subsidiaries; (d) Any change in the present board of directors or management of the Issuer, including any plans or proposals to change the number or term of directors or to fill any existing vacancies on the board; (e) Any material change in the present capitalization or dividend policy of the Issuer; (f) Any other material change in the Issuer's business or corporate structure; (g) Changes in the Issuer's charter, bylaws or instruments corresponding thereto or other actions which may impede the acquisition of control of the Issuer by any person; (h) Causing a class of securities of the Issuer to be delisted from a national securities exchange or to cease to be authorized to be quoted in an inter-dealer quotation system of a registered national securities association; (i) A class of equity securities of the Issuer becoming eligible for termination of registration pursuant to Section 12(g)(4) of the Securities Exchange Act of 1934; or (j) Any action similar to any of those enumerated above.

Percentage of Class

GEO is the record owner of the GEO Shares. As the sole member of GEO, NEA 18 VGE may be deemed to own beneficially the GEO Shares. As the sole general partner of NEA 18 VGE, NEA Partners 18 VGE may be deemed to own beneficially the GEO Shares. As the sole general partner of NEA Partners 18 VGE, NEA 18 VGE LLC may be deemed to own beneficially the GEO Shares. As members of NEA 18 VGE LLC, each of the Managers may be deemed to own beneficially the GEO Shares. Each Reporting Person disclaims beneficial ownership of the GEO Shares other than those shares which such person owns of record. The percentage of outstanding Common Stock of the Issuer which may be deemed to be beneficially owned by each Reporting Person is set forth on Line 13 of such Reporting Person's cover sheet. Such percentage was calculated based on 81,038,574 shares of Common Stock, which includes the sum of (i) 79,214,708 shares of Common Stock reported by the Issuer to be outstanding following the Offering as described in the Issuer's press release published on October 27, 2025 and (ii) the Exercisable Shares.

Number of Shares

Regarding the number of shares as to which such person has: (i) sole power to vote or to direct the vote: See line 7 of cover sheets (ii) shared power to vote or to direct the vote: See line 8 of cover sheets (iii) sole power to dispose or to direct the disposition: See line 9 of cover sheets (iv) shared power to dispose or to direct the disposition: See line 10 of cover sheets.

Transactions

Except as set forth in Item 3 above, none of the Reporting Persons has effected any transaction in the Common Stock during the last 60 days.

Shareholders

No other person is known to have the right to receive or the power to direct the receipt of dividends from, or any proceeds from the sale of, Common Stock beneficially owned by any of the Reporting Persons.

Date of 5% Ownership

Not applicable.

Not applicable.

Exhibit 1 - Agreement regarding filing of joint Schedule 13D. Exhibit 2 - Power of Attorney regarding filings under the Securities Exchange Act of 1934, as amended.

X4 Pharmaceuticals, Inc. — Schedule 13D | 13D Filings