Artiva halts cell therapy due to the deaths of two patients and cuts 94% of workforce

Reuters, October 27 - Artiva Biotherapeutics (ARTV.O) said on Tuesday that, following the deaths of two patients participating in its therapy trial, it will suspend the development of its experimental cell therapy for certain autoimmune diseases. As a result, the company's share price fell by 30% in pre-market trading.

The company also stated that it will lay off approximately 94% of its staff and is currently evaluating strategic options.

Details are as follows:

• Artiva's therapy, AlloNK, was previously being tested in a mid-stage clinical trial as a potential treatment for autoimmune diseases such as rheumatoid arthritis

• Artiva said that, during the trial, one patient experienced a fatal neurological event after treatment

• According to the company, both the principal investigator and an independent safety review committee assessed that the event was likely related to complications from the chemotherapy drug fludarabine

• Artiva added that another patient in the trial died suddenly about two months after starting treatment, with researchers concluding that this death was not related to AlloNK

• "After careful consideration, we have made a difficult decision: to terminate the development of AlloNK and seek other strategic alternatives," said CEO Fred Aslan

• As of September 30, Artiva held approximately $319.1 million in cash, cash equivalents, and investments

• According to its annual report, as of December 31, 2025, the company had 104 full-time employees

(To assist non-native English speakers, Reuters provides automated translations of its reports into various other languages. As automated translations may contain errors or lack required context, Reuters does not guarantee the accuracy of the translated text and provides it solely for the convenience of readers. Reuters assumes no responsibility for any damage or loss caused by the use of the automated translation feature.)