Artiva Biotherapeutics announced that the U.S. Food and Drug Administration has granted Fast Track Designation to AlloNK (AB-101) for the treatment of refractory rheumatoid arthritis in combination with rituximab. The company has simultaneously prioritized refractory RA as the program's lead indication, representing a strategic shift toward addressing a significant unmet medical need.
AlloNK is believed to represent the first drug candidate in the deep B-cell depleting therapeutic category to receive Fast Track Designation in refractory RA, positioning it as a potential first-in-class therapy to advance to pivotal trials in this indication.
Addressing Treatment-Refractory Patient Population
"We are prioritizing refractory RA as our lead autoimmune indication for AlloNK given the size of this underserved population," said Fred Aslan, M.D., Chief Executive Officer of Artiva. "Despite the many approved therapies in RA, there are over 100,000 patients in the United States who remain treatment refractory and could potentially benefit from a deep B-cell depleting therapy."
Rheumatoid arthritis affects over 1.5 million people in the United States and can cause painful joint inflammation, progressive joint damage, and disability if not adequately treated. While existing treatments such as methotrexate, TNF inhibitors, and B-cell depleting antibodies have improved outcomes for many patients, a significant subset becomes refractory and no longer responds to or tolerates these options. These patients face ongoing disease activity, increased risk of disability and joint destruction, and reliance on steroids or immunosuppressants that have long-term toxicity.
Mechanism and Clinical Advantage
AlloNK is designed to enhance the activity of B-cell-targeting antibodies, such as rituximab, through antibody-dependent cellular cytotoxicity. This mechanism of action is intended to drive deeper and more durable B-cell depletion than antibodies alone, potentially enabling long-term durable responses.
"Having contributed to the development of leading RA therapies including Humira and Orencia, I have witnessed the unmet need among patients with refractory RA who continue to suffer from inadequate disease control," said Subhashis Banerjee, M.D., Chief Medical Officer of Artiva.
The therapy's accessibility advantage lies in its administration format. Most patients with RA are treated at community rheumatology clinics rather than at large academic medical centers. Emerging deep B-cell depleting therapies such as CAR-T and T-cell engagers can be limited by the need for hospitalization or specialized oncology oversight, making them challenging for widespread use. With its infusion-ready, off-the-shelf format, and ease of use similar to IV-administered RA drugs, AlloNK in combination with rituximab has the potential to address this unmet need in a scalable and broadly accessible way.
Clinical Progress and Data Timeline
More than 20 patients have been treated with AlloNK plus monoclonal antibody therapy across refractory RA, Sjögren's disease, systemic lupus erythematosus, lupus nephritis, and systemic sclerosis in company-sponsored trials and an investigator-initiated basket trial, at 1 billion and 4 billion cells per AlloNK dose.
The company plans to share initial safety and translational data for over 20 patients treated with AlloNK plus monoclonal antibody across multiple autoimmune diseases in mid-November, including insights into the patient journey from community rheumatology sites. Translational data is expected to highlight uniform, consistent, deep B-cell depletion, while safety data is expected to highlight tolerability and ease-of-use of the regimen, including cyclophosphamide/fludarabine conditioning regimen, when administered and managed in community clinics.
Regulatory Pathway Forward
Artiva is on track to share clinical response data across dose levels from more than 15 refractory RA patients in the first half of 2026, with several patients having six or more months of follow-up. The company plans to conduct FDA regulatory interactions in the first half of 2026 to align on the pivotal trial design for AlloNK in refractory RA.
Depending on regulatory interactions with the FDA, AlloNK has the potential to become the first therapy within the emerging deep B-cell depletion category, which includes auto-CAR-T and T-cell engagers, to advance to a pivotal trial for patients with refractory RA.
AlloNK is an allogeneic, off-the-shelf, non-genetically modified, cryopreserved NK cell therapy candidate currently being evaluated in three ongoing clinical trials for the treatment of B-cell driven autoimmune diseases, including a company-sponsored basket trial across autoimmune diseases that includes rheumatoid arthritis and Sjögren's disease and an investigator-initiated basket trial in B-cell driven autoimmune diseases.
