Artiva said it would reduce its workforce by about 94% and has hired Leerink Partners to explore strategic options, including a merger and asset sale.

  • Artiva was testing AlloNK alongside Rituximab for rheumatoid arthritis and other autoimmune conditions in a Phase 2 trial
  • During the study, one patient died due to fludarabine-associated neurotoxicity.
  • A second participant died about two months into treatment, though investigations revealed that the death was unrelated to AlloNK or any other component of the study.

Shares of Artiva Biotherapeutics (ARTV) crashed 32% on Tuesday, heading for their worst session since April 2025, after the company stopped the development of its lead drug candidate following two patient deaths during a clinical trial.

At the time of writing, ARTV shares traded near eight-month lows.

Artiva Reports 2 Deaths

Artiva was testing AlloNK alongside Rituximab for rheumatoid arthritis and other autoimmune conditions in a Phase 2 trial. During the study, one patient died due to fludarabine-associated neurotoxicity. Fludarabine is a chemotherapy drug.

After the company notified the U.S. Food and Drug Administration (FDA) about the death, the regulator asked Artiva to pause enrolment and dosing. The company also paused enrolment of its Phase 3 trial.

A second participant in the trial experienced sudden death about two months after initiating treatment. An investigator found that the death was unrelated to AlloNK or any other component of the study treatment regimen, and the cause of death has not been determined.

Artiva also stated that while the treatment initially showed promising results, longer-term data indicated its benefits did not last long enough to justify further development.

“We are deeply saddened by the deaths of two patients who participated in our clinical studies and extend our sincere condolences to their families. We plan to provide findings from the first case, which was assessed as likely related to fludarabine toxicity, given its widespread use in cell therapy conditioning regimens,” said Fred Aslan, CEO of Artiva Biotherapeutics.

What Happens Next?

Artiva said it would reduce its workforce by about 94% and has hired Leerink Partners to explore strategic options, including a merger, an asset sale, a licensing agreement, or liquidation. Artiva reported about $319.1 million in cash, cash equivalents and investments as of September 30.

Retail Turns Bullish On ARTV Despite Crash

Retail sentiment for ARTV on Stocktwits turned ‘bullish’ from ‘neutral’ over the past 24 hours despite the slump.  

The stock has edged marginally higher in 2026.

Also read: Aclaris Reports Positive Asthma, Eczema Drug Trial Results — So, Why Is ACRS Stock Down Nearly 8%?

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