FTP-637

Topline data from Phase 3 ONWARD trials for Alumis’ ESK-001 in moderate-to-severe plaque psoriasis on track for readout in first half of 2026; Topline data from Phase 2b LUMUS trial in systemic lupus erythematosus on track for readout in 2026 Evaluation underway of development plan for ACELYRIN’s lonigutamab to confirm differentiation in a capital efficient manner Pro forma cash position of approximately $737 million as of December 31, 2024, provides runway into 2027, beyond expected multiple clinical readouts for highly differentiated late-stage portfolio Alumis and ACELYRIN stockholders to own ~55% and ~45%, respectively, of combined company on a fully diluted basis Combined company will operate under Alumis name with current Alumis executive team SOUTH SAN FRANCISCO, CA and LOS ANGELES, CA, USA I February 06, 2025 I Alumis Inc. (Nasdaq: ALMS), a clinical-stage biopharmaceutical company developing therapies using a precision approach to optimize clinical outcomes and significantly improve the lives of patients with immune-mediated diseases, and ACELYRIN, INC. (Nasdaq: SLRN), a late-stage clinical biopharma company focused on accelerating the development and delivery of transformative medicines in immunology, today announced a definitive merger agreement under which Alumis and ACELYRIN will merge in an all-stock transaction. Martin Babler, President, Chief Executive Officer and Chairman of Alumis, said, “Through this combination with ACELYRIN, Alumis will have the financial flexibility and runway to advance an expanded late-stage pipeline, now including lonigutamab, and build commercial capabilities. Since completing our IPO, Alumis has operated with speed and rigor, and the multiple development milestones expected in 2025 and 2026, coupled with potential additional indications for ESK-001, represent exciting breakthroughs for our patients and value-driving opportunities for the combined company’s stockholders. As we move forward together, we will maintain financial discipline and a flexible capital allocation strategy with the goal of maximizing the value of our highly differentiated portfolio.” Bruce Cozadd, Chair of the ACELYRIN Board of Directors and member of the Board Transaction Committee said, “This merger represents the culmination of a thorough strategic review process by our Board and management team to determine the best and most value-maximizing path forward for ACELYRIN. We are confident that Alumis is the right partner to optimize the development of lonigutamab and together deliver long-term stockholder value.” “We are pleased to join with Alumis and further advance our mission of developing and delivering transformative medicines in immunology,” said Mina Kim, Chief Executive Officer of ACELYRIN. “This merger brings together two complementary organizations and pipelines, enabling the company to leverage the benefits of combined development and commercial expertise, as well as catalyst diversification, to achieve even more together. I am deeply grateful to the entire ACELYRIN team, whose efforts have made today’s milestone possible, and am excited that Alumis shares our mission of providing patients with life-changing new treatment options.” Alumis and ACELYRIN had cash, cash equivalents and marketable securities of approximately $289 million and approximately $448 million, respectively, on a preliminary basis, as of December 31, 2024. With a pro forma cash position of approximately $737 million as of December 31, 2024, and continued operating discipline, Alumis expects that this cash position provides runway to advance the combined company’s pipeline through multiple planned key data readouts across several clinical trials and to fund operating expenses and capital expenditure requirements into 2027. Combined Pipeline The combined company will benefit from a differentiated late-stage portfolio of therapies and increased resources enabling the development of life-changing medicines. Together, the combined company will leverage its track record of R&D success, along with its proprietary data and analytics platform, which utilizes key genetic and translational insights to optimize outcomes to patients. Alumis ACELYRIN Transaction Terms Under the terms of the agreement, ACELYRIN stockholders will receive 0.4274 shares of Alumis common stock for each share of ACELYRIN common stock owned. Upon the close of the transaction, Alumis stockholders will own approximately 55% of the combined company and ACELYRIN stockholders will own approximately 45% of the combined company, on a fully diluted basis. The transaction was unanimously recommended and approved by the disinterested directors of each company’s Board. Headquarters and Leadership Following close, the combined company will be led by the current Alumis executive team and will comprise a deep bench of talented professionals and medical experts that have successfully advanced multiple programs through clinicals trials to commercialization. This will include key members of ACELYRIN’s team who will ensure continuity and optimization of the lonigutamab development plan. The combined company’s Board will expand to nine directors, including two additional directors from ACELYRIN’s Board. The combined company will operate under the Alumis name with its corporate headquarters remaining in South San Francisco. Timing and Approvals The transaction is expected to close in the second quarter of 2025, subject to approval by the stockholders of both companies and satisfaction of other customary closing conditions. Stockholders representing approximately 62% of Alumis voting common stock and approximately 24% of ACELYRIN common stock have entered into voting agreements in support of the transaction. Conference Call and Webcast Alumis and ACELYRIN will host a joint conference call and webcast today at 5:00 p.m. E.T. to discuss the transaction. The webcast will be available live via the link here . The webcast link and associated presentation materials will be available on the investor relations section of each company’s website. Advisors Morgan Stanley & Co. LLC is serving as financial advisor to Alumis, and Cooley LLP is serving as its legal counsel. Guggenheim Securities, LLC is serving as financial advisor to ACELYRIN and Fenwick & West LLP is serving as its legal counsel. About Alumis Alumis is a clinical-stage biopharmaceutical company developing oral therapies using a precision approach to optimize clinical outcomes and significantly improve the lives of patients with immune-mediated diseases. Leveraging its proprietary precision data analytics platform, Alumis is building a pipeline of molecules with the potential to address a broad range of immune-mediated diseases as monotherapy or combination therapies. Alumis’ most advanced product candidate, ESK-001, is an oral, highly selective, small molecule, allosteric inhibitor of tyrosine kinase 2 that is currently being evaluated for the treatment of patients with moderate-to-severe plaque psoriasis and systemic lupus erythematosus. Alumis is also developing A-005, a CNS-penetrant, allosteric TYK2 inhibitor for the treatment of neuroinflammatory and neurodegenerative diseases. Beyond TYK2, Alumis’ proprietary precision data analytics platform and drug discovery expertise have led to the identification of additional preclinical programs that exemplify its precision approach. Incubated by Foresite Labs and led by a team of industry veterans experienced in small-molecule compound drug development for immune-mediated diseases, Alumis is pioneering a precision approach to drug development to potentially produce the next generation of treatment to address immune dysfunction. About ACELYRIN ACELYRIN, INC. (Nasdaq: SLRN) is focused on providing patients life-changing new treatment options by identifying, acquiring, and accelerating the development and commercialization of transformative medicines. ACELYRIN’s lead program, lonigutamab, is a subcutaneously delivered monoclonal antibody targeting IGF-1R being investigated for the treatment of thyroid eye disease. SOURCE : ACELYRIN

Dive Brief:Alumis and Acelyrin are merging, the biotechnology companies said Thursday afternoon, in an all-stock deal that leaves the combined company with a bigger cash balance and three drugs in clinical testing.Per deal terms, Acelryinstockholders will receive 0.4274 shares of Alumis stock for each share they own,leaving them with about 45% of the combined company and Alumis equity holders with 55%. The new company, which will keep the Alumis name and be run by its executive team, would have $737 million in cash, enough to keep operating into 2027.The merged entity will continue to develop Alumis two so-called TYK2 inhibitors, one of which is being developed for plaque psoriasis and lupus while the other is targeting neuroinflammatory conditions like multiple sclerosis. Acelyrinstop prospect, a thyroid eye disease drug called lonigutamab, is part of the deal, too, but the program will be re-evaluated to “confirm its differentiation in a capital efficient manner,“ the companies said.Dive Insight:Prior to the merger, Acelyrin and Alumis were struggling with depressed share prices. The two biotechswent public in 2023 and 2024, respectively, in large initial public offerings Acelyrin netted $540 million, while Alumis raised $250 million but both have since lost most of their market value.Acelryinhas already changed up its strategy. The company went public to support development of a drug, izokibep, being tested in multiple autoimmune conditions. But izokibep failed a late-stage study in September 2023and, a year later, was shelved in a restructuring that saw Acelyrin focus resources around lonigutamab. The company has been discussing plans to bring lonigutamabinto late-stage testing, but earlier results havent been convincing enough to lift its share price, which closed Thursday at less than $2.Alumis, meanwhile, has seen its stock sink about two thirds from its IPO price. Though the company has a TYK2 inhibitor a type of oral autoimmune medicine in late-stage testing, it trails other, similar drugs. Its development has also advanced during a crowding of competition for oral autoimmune therapies and while the only approved TYK2 blocker, Bristol Myers Squibbs Sotyktu, hasnt yet met expectations commercially.Still, Alumis has claimed its top TYK2 drug, ESK-001, could be superior to Sotyktu, and that a second candidate, A-005,has the potential to treat inflammation in the central nervous system. For ESK-001, data are expected next year from a Phase 3 trial in psoriasis and a mid-stage study in lupus. A-005 should have results from a Phase 2 test in multiple sclerosis as well.The merger, then, is a creative and capital efficient transaction that gives Alumis a significant influx of cash to get to those readouts while relieving any potential financing overhang,wrote Leerink Partners analyst Thomas Smith.The deal also enables Acelyrin shareholders to bet on those results, while handing Alumis a program in lonigutamab it could advance in parallel.We believe that scale and diversity of the portfolio is extremely important, and sufficient capital is critical, Alumis CEO Martin Babler said on a Thursday afternoon call with analysts.The drugs fate, though, is unclear. While Acelyrin has pitched it as more convenient alternativeto Amgens thyroid eye disease drug Tepezza, Wall Street analysts have been skeptical of its ability to stand out from Tepezza and a competing program from Viridian Therapeutics.Leerink analyst Smith, who connected with management following the conference call, said executives reiterated they are pausing Acelyrins previously stated plans to move lonigutamab directly into Phase 3 testing. A decision will only be made after fully assessing early study results and finding a study path that can show clear clinical differentiation, he wrote.We do not expect significant investment in lonigutamab in the near term, Smith added.The companies anticipate that the deal will close in the second quarter. '