Welcome to our dedicated page for X4 Pharmaceuticals SEC filings (Ticker: XFOR), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
X4 Pharmaceuticals, Inc. filings document a rare-disease biopharmaceutical issuer with commercial activity for XOLREMDI and development work around mavorixafor. Its 8-K reports cover operating and financial results, material agreements, restructuring actions, executive and board changes, and capital-structure updates involving common stock, pre-funded warrants, registration rights, and equity purchase arrangements.
Proxy materials describe shareholder voting matters, board composition, committee assignments, executive compensation, equity awards, and governance procedures. The filing record also includes disclosures tied to the company’s inducement and equity incentive practices, financing arrangements, and formal reporting of material corporate events.
Saturn V Capital Management LP and Xiaoying Tian report beneficial ownership of 6,433,481 shares of X4 Pharmaceuticals, Inc. common stock, representing 7.36% of the class. The percentage is based on 87,436,688 shares outstanding as of October 31, 2025.
The shares are held across pooled investment vehicles and managed accounts (the “Clients”) for which Saturn V serves as investment manager. Saturn V and Ms. Tian have shared voting and dispositive power over all 6,433,481 shares, with no sole voting or dispositive power.
No individual Client holds or beneficially owns five percent or more of X4’s outstanding shares, and both Saturn V and Ms. Tian expressly disclaim beneficial ownership of the shares held by the Clients. The filing certifies that the securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of X4 Pharmaceuticals.
X4 Pharmaceuticals received an updated ownership report from Nantahala Capital Management and its principals. As of December 31, 2025, the reporting group may be deemed to beneficially own 2,449,468 shares of common stock, representing 2.80% of the outstanding shares.
The filing shows that Nantahala, Wilmot B. Harkey, and Daniel Mack share voting and dispositive power over these shares through funds and separately managed accounts. They certify the holdings are kept in the ordinary course of business and are not intended to change or influence control of X4 Pharmaceuticals.
Morgan Stanley and its investment management arm have reported a significant passive stake in X4 Pharmaceuticals, Inc. They beneficially own 8,196,489 shares of X4 common stock, representing 9.4% of the outstanding class as of December 31, 2025.
The filing shows no sole voting or dispositive power; all 8,196,489 shares are held with shared voting and shared dispositive power. The firms certify the holdings are in the ordinary course of business and not for the purpose of changing or influencing control of X4 Pharmaceuticals.
FMR LLC and Abigail P. Johnson report a significant passive ownership stake in X4 Pharmaceuticals, Inc. common stock on an amended Schedule 13G. They beneficially own 8,499,100 shares, representing 9.7% of the outstanding common stock, with sole dispositive power over all reported shares.
The filing states the shares were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of X4 Pharmaceuticals, or in connection with any control-related transaction.
Empery Asset Management, LP and Ryan M. Lane report a significant stake in X4 Pharmaceuticals, Inc. They beneficially own 9,043,894 shares of X4 Pharmaceuticals common stock as of December 31, 2025, including 92,789 shares issuable upon exercise of warrants, representing 9.99% of the outstanding common stock.
This percentage is calculated using 90,436,688 shares outstanding, which includes 87,436,688 shares reported as of October 31, 2025 plus 3,000,000 shares issued from warrant exercises completed by December 31, 2025. The warrants are subject to a 9.99% “Blocker” that prevents the reporting persons from exercising warrants if it would push their ownership above 9.99% of the company’s outstanding common stock.
Empery Asset Management acts as investment manager to the funds that hold the shares and warrants, and Lane is the individual who ultimately oversees the investment manager. They certify that the holdings are in the ordinary course of business and not for the purpose of changing or influencing control of X4 Pharmaceuticals.
X4 Pharmaceuticals director Bridger Gary received a new stock option grant. On 01/01/2026, he was awarded options to purchase 110,000 shares of X4 Pharmaceuticals common stock at an exercise price of $4.00 per share, expiring on 01/01/2036.
The options will vest in full only if stockholders approve an increase in the share reserve under the company’s Amended and Restated 2017 Equity Incentive Plan at the company’s 2026 annual meeting of stockholders, and if he continues providing services through that date. This filing reports an equity-based compensation grant rather than a share sale.
X4 Pharmaceuticals (XFOR) filed its Q3 2025 10‑Q, highlighting early commercial traction, a major partnership, and cost actions. Total revenue was $1.8 million for the quarter, driven by $1.6 million in U.S. product sales of XOLREMDI and $0.2 million of license and other revenue. For the nine months, revenue reached $32.5 million, primarily from $28.3 million recognized under the Norgine license and supply agreement.
The company reported a Q3 net loss of $29.8 million and a nine‑month net loss of $55.3 million. Cash, cash equivalents and short‑term marketable securities were $122.2 million as of September 30, 2025. Long‑term debt stood at $76.1 million. A 1‑for‑30 reverse stock split was effected on April 28, 2025.
X4 executed significant financings: approximately $81.0 million in net proceeds from an August private placement and approximately $145.6 million in net proceeds from an October underwritten offering. The company undertook two restructurings in 2025, including an additional ~50% workforce reduction announced in September, recording about $4.9 million of related Q3 charges and ending Q3 with $3.7 million of accrued severance. As of October 31, 2025, shares outstanding were 87,436,688.
X4 Pharmaceuticals, Inc. filed an 8-K stating it furnished a press release announcing financial results and other business highlights for the third quarter ended September 30, 2025. The release is attached as Exhibit 99.1 and incorporated by reference. The company notes the Item 2.02 information is furnished, not filed, under the Exchange Act.
X4 Pharmaceuticals (XFOR) Executive Chairman, also a director, reported a grant of stock options for 2,329,154 shares at an exercise price of $1.42 per share. The options were granted on August 12, 2025 and became eligible to vest after a performance-based condition was satisfied on October 29, 2025.
One third of the shares underlying the option vest on August 12, 2026, with the remainder vesting in equal monthly installments over the following 24 months, subject to continued service. The options expire on August 12, 2035.
X4 Pharmaceuticals (XFOR) reported an insider equity award. The company’s President filed a Form 4 disclosing stock options to purchase 2,329,154 shares at an exercise price of $1.42. The options were granted on August 12, 2025 and became subject to reporting when a performance-based vesting condition was satisfied on October 29, 2025.
One third of the shares subject to the option will vest on August 12, 2026, with the remaining shares vesting in equal monthly installments over the following 24 months, contingent on continued service. The options expire on August 12, 2035. Following the reported transaction, 2,329,154 derivative securities were beneficially owned, held directly.