Artiva Biotherapeutics cuts 94% of workforce after patient deaths and failed autoimmune cell therapy

Artiva Biotherapeutics announced it is halting development of its AlloNK natural killer cell therapy for autoimmune diseases and is laying off roughly 94% of its employees.

The AlloNK product, an off‑the‑shelf NK cell therapy, was being pursued for rheumatoid arthritis and other B‑cell‑driven conditions, with a pivotal Phase 3 trial slated for this year. A review of the risk‑benefit profile led the company to abandon the program, citing insufficient durability of clinical responses.

Safety concerns intensified after two participants in a Phase 2a basket trial died. One death was linked to fludarabine, a chemotherapy agent used in the lymphodepletion regimen, and the FDA subsequently asked Artiva to pause enrollment and dosing. The second death occurred suddenly about two months after treatment initiation.

The combined safety setbacks and lack of durable efficacy prompted Artiva to drastically reduce its workforce, signaling a major setback for the biotech and its investors.