Alumis Announces Late-Breaker Oral Presentation of Phase 3 Data for Envudeucitinib in Moderate-to-Severe Plaque Psoriasis at 2026 American Academy of Dermatology Annual Meeting

– Phase 3 data presentation highlighting results from the ONWARD1 and ONWARD2 clinical trials of envudeucitinib –

– Phase 2 STRIDE e-poster presentation to describe disease biomarker activity of envudeucitinib –

– Alumis to host investor webcast on Sunday, March 29, 2026, at 5:00 pm MDT / 7:00 pm EDT –

SOUTH SAN FRANCISCO, Calif., March 18, 2026 — Alumis Inc. (Nasdaq: ALMS), a late-stage biopharmaceutical company developing next-generation targeted therapies for patients with immune-mediated diseases, today announced that results from its Phase 3 ONWARD program evaluating envudeucitinib, a next-generation oral tyrosine kinase 2 (TYK2) inhibitor for moderate-to-severe plaque psoriasis, have been accepted for a late-breaking oral presentation, and that a new biomarker analysis from the Phase 2 STRIDE trial of envudeucitinib has been accepted as an e-poster at the 2026 American Academy of Dermatology (AAD) Annual Meeting, taking place March 27–31, 2026, in Denver, Colorado.

Details regarding the presentations are as follows:

Late-Breaking Oral Presentation

Title: Envudeucitinib (ESK-001) in moderate-to-severe plaque psoriasis: 24-week results from the randomized, double-blind, active comparator- and placebo-controlled, Phase 3 ONWARD 1 and 2 studies Location: Bellco Theatre 3 Date and Time: March 28, 2026, at 11:12 am MDT

E-Poster Presentations

Title: Envudeucitinib Attenuates Inflammatory Biomarkers in Plaque Psoriasis at Both a Proteomic and Transcriptomic Level: A Subgroup Analysis of Tape Strip Biomarkers from the STRIDE Phase 2 Clinical Trial Poster number: 73714

The presentations will be made available under the Publications section of the Alumis website on March 28, 2026 in accordance with the AAD embargo policy.

Investor Conference Call and Webcast Details

Alumis will also host a webcast for the investment community on Sunday, March 29, 2026, at 5:00 pm MDT (7:00 pm EDT) to review the Phase 3 ONWARD data being presented at AAD. The live webcast can be accessed via this link or on the Events tab on the Investors section of the Company’s website. A replay of the webcast will be made available on the Company’s website following the call.

About Envudeucitinib

Envudeucitinib is a next‑generation, highly selective, oral allosteric inhibitor of tyrosine kinase 2 (TYK2) designed to correct immune dysregulation across a range of diseases driven by proinflammatory mediators, including IL-23, IL-17, and Type I interferon. Clinical data indicate its selective targeting delivered sustained, maximal 24-hour inhibition in patients with psoriasis while minimizing off-target binding and effects. Alumis is currently evaluating the long-term efficacy and safety of envudeucitinib in the Phase 3 ONWARD3 clinical program for moderate-to-severe plaque psoriasis. Envudeucitinib is also being evaluated in LUMUS, a potentially pivotal Phase 2b clinical trial in patients with systemic lupus erythematosus, with topline data expected in the third quarter of 2026.

About Alumis

Alumis is a late-stage biopharma company developing next-generation targeted therapies with the potential to significantly improve patient health and outcomes across a range of immune-mediated diseases. Leveraging its proprietary data analytics platform and precision approach, Alumis is developing a pipeline of oral tyrosine kinase 2 inhibitors, consisting of envudeucitinib for the treatment of systemic immune-mediated disorders, such as moderate-to-severe plaque psoriasis and systemic lupus erythematosus, and A-005 for the treatment of neuroinflammatory and neurodegenerative diseases. In addition, the pipeline includes lonigutamab, a subcutaneously delivered anti–insulin-like growth factor 1 receptor therapy for the treatment of thyroid eye disease, as well as several preclinical programs identified through this precision approach. For more information, visit www.alumis.com or follow us on LinkedIn or X.