aibioAlumis carries ACELYRIN securities class action over izokibep trial; dismissal motion pending
Tickers ALMS
Alumis (Nasdaq: ALMS) inherited Boukadoum v. Acelyrin in its May 2025 merger. The filing names ACELYRIN and unnamed officers and directors; ACELYRIN's 2024 signers are listed.
Key facts
- Company
- Alumis Inc. (NASDAQ: ALMS)
- News type
- Legal
- Primary source
- Alumis 10-Q for the quarter ended June 30, 2026 (SEC EDGAR)
Alumis Inc. (Nasdaq: ALMS) inherited a federal securities class action when it completed its merger with ACELYRIN, Inc. The case, Boukadoum v. Acelyrin, Inc. et al., No. 2:23-cv-09672-FMO-MAA, is pending in the United States District Court for the Central District of California. Alumis described it in its 10-Q filed August 13, 2026. A purported class action was commenced on November 15, 2023, and joint lead plaintiffs were appointed on February 15, 2024. The named plaintiff in the caption is Boukadoum.
The amended complaint names ACELYRIN and "then-current and former executive officers and directors" as defendants. The 10-Q does not name the individuals. ACELYRIN's own annual report, filed March 28, 2024, was signed by its chief executive officer, its chief financial officer and its other directors, who are listed below.
The case
The amended complaint, filed March 26, 2024, alleges the defendants violated the Exchange Act and the Securities Act by misleading investors about the Phase 2b trial of izokibep in hidradenitis suppurativa. The original complaint followed ACELYRIN's announcement of week 16 results from the Part B portion of that trial. The plaintiffs seek damages and an award of costs and expenses, including attorneys' fees and expert fees. The 10-Q does not state the class period.
Defendants
The named defendant entity is ACELYRIN, Inc., now a direct wholly owned subsidiary of Alumis. The 10-Q does not list the individual defendants. ACELYRIN's 10-K for 2023, filed March 28, 2024, was signed by these people: Shao-Lee Lin, M.D., Ph.D., founder, chief executive officer and director; Gil M. Labrucherie, chief financial officer; and directors Bruce C. Cozadd, Dan Becker, M.D., Ph.D., Alan B. Colowick, M.D., M.P.H., Henry O. Gosebruch, Patrick Machado, J.D., Beth Seidenberg, M.D., Dawn Svoronos and Lynn Tetrault. Neither filing says these individuals are defendants.
Where it stands
The defendants moved to dismiss the amended complaint on May 3, 2024. The court granted that motion in January 2026 with leave to amend. The plaintiffs filed a second amended complaint on February 5, 2026, which again seeks damages and costs. The defendants moved to dismiss it on February 19, 2026, and the 10-Q says that motion "remains pending." Alumis's only 8-K since the 10-Q, filed September 1, 2026 on lupus trial results, does not mention the case.
Alumis says it cannot estimate its possible loss because the case is at an early stage, and that any amount could be material to its financial statements even if it prevails. As of June 30, 2026, it did not consider any payment probable or reasonably estimable and had accrued nothing. It cannot say how long the case may take to resolve.
Why it matters to shareholders
Alumis assumed ACELYRIN's liabilities in the merger. The 10-Q says Alumis completed the ACELYRIN Merger on May 21, 2025, for purchase consideration of $238.1 million that included 48,653,549 shares of Alumis common stock and the fair value of replacement awards. Alumis says it could be forced to spend significant resources defending this and any related suits and may not prevail.
The company also warns that more suits could follow over the same or other matters, naming Alumis or its officers and directors. Separately, Alumis says it has agreed to indemnify its directors and officers to the extent Delaware law permits. It reports that it has not paid any claims or been required to defend any action under those obligations, had no material indemnification claims at June 30, 2026, and recorded no related liabilities. The 10-Q does not say whether insurance covers the class action.
Related matters
The 10-Q reports a second dispute that came with ACELYRIN. On December 31, 2025, Climb Bio, Inc., the parent of Tenet Medicines, Inc., filed a complaint in Delaware Superior Court seeking a declaratory judgment that budoprutug is not a "Product" under ACELYRIN's January 2024 asset purchase agreement with Tenet, so that no milestone or royalty payments are owed. The 10-Q does not say which entity Climb Bio sued. The company disputes that reading. In January 2026 it issued a notice of material breach over an unpaid $3.0 million development milestone, and it intends to seek recovery through litigation. The matter remains pending.