Artiva drops its NK cell therapy for autoimmune disease and cuts 94% of staff

Artiva Biotherapeutics is ending development of AlloNK, its off-the-shelf natural killer (NK) cell therapy for autoimmune disease, and cutting about 94% of its workforce. The San Diego company announced the decision on 27 October after reviewing the programme's overall risk and benefit, including updated clinical data, longer follow-up and two patient deaths.

What happened

AlloNK (AB-101) is an allogeneic NK cell therapy that is not genetically modified. Artiva was testing it with rituximab in rheumatoid arthritis and other B-cell-driven autoimmune diseases. The company says B-cell depletion and clinical activity matched earlier results, but responses did not last long enough to justify going further. No more patients will be dosed and the planned Phase 3 pivotal trial will not start.

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One participant in the Phase 2a basket trial died of leukoencephalopathy after the protocol's lymphodepleting chemotherapy, cyclophosphamide and fludarabine. The investigator and an independent safety review judged it likely related to fludarabine neurotoxicity, and the FDA asked Artiva to pause Phase 2a enrolment and dosing. A second participant died suddenly about two months after starting treatment. The investigator judged that death unrelated to AlloNK or other study treatments, and the cause has not been determined.

"we have made the difficult decision to discontinue development of AlloNK" Fred Aslan, M.D., chief executive officer, Artiva Biotherapeutics

The numbers

BioSpace reports that Artiva had 115 employees at 30 June, so the cut affects about 108 roles and should be finished in the first quarter of 2027. Preliminary, unaudited cash and investments were about $319.1 million at 30 September. BioSpace also notes Artiva raised $179 million in its 2024 IPO and $300 million in an offering in May 2026.

What's next

The board is reviewing strategic alternatives, which could include a merger, a sale or licensing of assets, or dissolution and liquidation. Leerink Partners is advising. Artiva has also cancelled its planned ACR Convergence 2026 presentation and its 9 November investor webcast, and says it will not give further updates on the review unless the board approves a course of action, the process ends or disclosure is required.

The bigger picture

Artiva's decision is a reminder of two questions every cell therapy programme in autoimmune disease has to answer before Phase 3: is the conditioning regimen safe enough for patients who are not facing cancer, and do responses last? The company's cash position means its next step will be a corporate decision as much as a scientific one.

What it means for hiring

A cut of this size releases experienced cell therapy people in clinical development, translational science and manufacturing into the San Diego market at once. For companies hiring in the region, this is a moment to be visible.
The safety findings put conditioning regimens under a brighter light. We'd expect autoimmune cell therapy companies to lean harder on safety physicians and clinical scientists with neurotoxicity experience.
Well-funded companies in a strategic review often keep a very small team to run the process. Interim finance, legal and business development leaders with wind-down or reverse-merger experience tend to be in demand in these situations.

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