Artiva Biotherapeutics to Cut 94% of Staff, Halt Autoimmune Cell Therapy After Two Trial Deaths

Artiva Biotherapeutics will lay off 94% of its staff and stop developing its experimental "natural killer" cell therapy AlloNK for autoimmune conditions after two patient deaths in a clinical trial, the company said Tuesday. Both deaths appeared unrelated to AlloNK, Artiva said. One participant developed leukoencephalopathy that a study investigator linked to fludarabine, a chemotherapy used to prepare patients for treatment. The other patient died suddenly about two months after starting treatment, with a researcher again concluding no component of the regimen was to blame. Artiva reported the first event to the FDA, which requested a pause of its Phase 2a trial; the company also stopped planned enrollment and dosing in a Phase 3 study. Artiva said AlloNK's effects did not show the durability needed to support continued development. The company held $319.1 million in cash as of the end of September and has hired a financial adviser to begin a strategic review, which often ends in a reverse merger or asset sale.