aibioAlumis and ACELYRIN agree to all-stock merger with $737 million pro forma cash
Tickers ALMS
ACELYRIN holders would receive 0.4274 Alumis shares for each share they own, and the $737 million pro forma cash figure rests on preliminary year-end balances.
Key facts
- Company
- Alumis Inc. (NASDAQ: ALMS)
- News type
- Mergers
- Primary source
- Alumis Inc. 8-K (2025-02-06)
Alumis Inc. (Nasdaq: ALMS) and ACELYRIN, Inc. (Nasdaq: SLRN) agreed on February 6, 2025 to combine in an all-stock merger, according to a press release attached to an 8-K the same day. Alumis is developing ESK-001, a TYK2 inhibitor in Phase 3 testing for psoriasis. ACELYRIN is advancing lonigutamab, a subcutaneous anti-IGF-1R being tested in thyroid eye disease.
The terms
Under the merger agreement, Arrow Merger Sub, Inc. will merge into ACELYRIN, which will survive as a wholly owned Alumis subsidiary. Each ACELYRIN common share will be converted into 0.4274 shares of Alumis common stock. On a fully diluted basis, Alumis holders would own about 55% of the combined company and ACELYRIN holders about 45%.
ACELYRIN options with an exercise price of $18.00 or less will convert into Alumis options, adjusted by the exchange ratio. Options priced above $18.00 will be cancelled without any payment. Unvested restricted stock units will convert into Alumis units. The combined company's board will grow to nine directors, including two from ACELYRIN's board. It will be led by the current Alumis executive team, and its headquarters stays in South San Francisco.
The deal needs an effective Form S-4 registration statement, approval from a majority of ACELYRIN's outstanding shares, and approval from a majority of the votes cast at Alumis's stockholder meeting. Voting agreements cover about 62% of Alumis's voting common stock and about 24% of ACELYRIN's common stock, so most ACELYRIN shares are not yet committed. Each board acted on a unanimous recommendation from a special committee of independent and disinterested directors.
The release names Morgan Stanley & Co. LLC as financial advisor to Alumis and Cooley LLP as its legal counsel. Guggenheim Securities, LLC is financial advisor to ACELYRIN and Fenwick & West LLP is its legal counsel.
Cash and the runway into 2027
Alumis had about $289 million and ACELYRIN about $448 million in cash, cash equivalents and marketable securities as of December 31, 2024. Both figures are preliminary. The companies add them to a pro forma total of about $737 million and say it provides runway into 2027, through what they call "multiple planned key data readouts."
The release does not give the combined company's expected spending or net loss, so the runway cannot be checked against burn. Chief executive Martin Babler said the company will "maintain financial discipline and a flexible capital allocation strategy."
What the pipeline still has to show
The company calls ESK-001 a potentially best-in-class molecule. Its evidence so far comes from a Phase 2 trial, where the company says the drug showed a favorable safety profile and high clinical responses in psoriasis. Those are the company's descriptions. Phase 3 topline data in psoriasis are expected in the first half of 2026, and Phase 2b data in systemic lupus erythematosus in 2026. A 52-week update from the psoriasis program is due in 2025.
Alumis also has A-005, a central nervous system penetrant TYK2 inhibitor. The release cites a Phase 1 trial in healthy volunteers, which it says showed the drug was well tolerated and showed an ability to cross the blood-brain barrier. A Phase 2 multiple sclerosis trial is expected to start in the second half of 2025, with topline data in 2026.
Lonigutamab is the least defined part of the release. The company says the drug has shown robust efficacy in thyroid eye disease, comparable to the intravenous standard of care, with a favorable safety profile, but it is still in a Phase 2 trial. ACELYRIN plans to re-evaluate the program "to confirm its differentiation in a capital efficient manner." In a February 6 email to employees, Babler said Alumis does not have clear plans to share yet for lonigutamab, and that it will evaluate the work only after the deal closes.
Approvals and break fees
The companies expect to close in the second quarter of 2025, and Alumis will file a Form S-4 with a joint proxy statement and prospectus. Either side may end the agreement if the deal has not closed before July 7, 2025. A party that terminates to accept a superior proposal, among other cases, owes the other a termination fee of $10 million.