Artiva Biotherapeutics shares fell 32% on Tuesday after the company said it is halting development of its NK cell therapy AlloNK (AB-101), including a planned phase 3 pivotal trial. Longer-term data showed the durability of clinical response fell short of the threshold needed to continue. The company also cited two recent Grade 5 safety events. One, a fatal neurological event in a phase 2a trial, was assessed as likely related to the chemotherapy drug fludarabine. The US Food and Drug Administration (FDA) had asked Artiva to pause enrollment and dosing. Artiva will cut its workforce by about 94% and is weighing strategic alternatives, including a merger, asset sale, or liquidation. It has hired Leerink Partners as financial adviser. The company held about $319.1 million in cash and investments as of September 30, 2026.

Artiva Biotherapeutics announces multiple AlloNK(R) data presentations at the american college of rheumatology (ACR) Convergence 2026. * Oral presentation highlighting updated clinical data from at least 20 patients with refractory rheumatoid arthritis (RA), 11 patients with Sjögren disease (SjD) and at least five patients with systemic sclerosis (SSc) treated with AlloNK plus rituximab in the ongoing Phase 2a basket trial, all with at least six months of follow-up * Poster presentation highlighting deep, consistent B-cell depletion comparable to that observed with CD19 CAR T-cell therapies and a favorable tolerability profile across immune-mediated diseases * Poster presentation characterizing the high unmet medical need and low clinical response rates among patients with refractory RA following an inadequate response to at least two distinct classes of biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs), a population similar to that being studied in the Phase 3 registrational trial * Live webcast on Monday, November 9, 2026 at 8:15 am EST to review Artiva's presentations, including an in-depth analysis of data from at least 10 patients with refractory RA who have at least six months of follow-up and would meet key eligibility criteria for the Phase 3 registrational trial SAN DIEGO, Oct. 02, 2026 (GLOBE NEWSWIRE) - Artiva Biotherapeutics, Inc. (Nasdaq: ARTV) (Artiva), a clinical-stage biotechnology company whose mission is to develop effective, safe and accessible cell therapies for patients with debilitating autoimmune diseases, today announced one oral and two poster presentations at ACR Convergence 2026 featuring updated data from its AlloNK(R) program and a registry analysis of the high unmet medical need in refractory RA. Artiva will host a live webcast on Monday, November 9, 2026, at 8:15 am EST to review its ACR presentations and updated clinical data from at least 20 patients with refractory RA who have at least six months of follow-up. The webcast will include an in-depth analysis of data from at least 10 of these patients who would meet key eligibility criteria for the Phase 3 registrational trial. The following abstracts will be presented at ACR Convergence 2026, taking place November 6 - 11, 2026, at the Orange County Convention Center in Orlando: | 1899 Oral Presentation | AB-101, Outpatient-Administered, Non-Genetically Modified NK Cells in Combination with Rituximab Generate Robust Efficacy Responses Comparable with Autologous CAR T in 34 Patients with Rheumatologic Diseases | | Presenting Author: | Guillermo J. Valenzuela, M.D., F.A.C.R. Medical Director, Integral Rheumatology & Immunology Specialists | | Session: | Abstracts: Rheumatoid Arthritis - Treatment | | Date/Time/Location: | Monday, November 9, 2026 at 3:00 - 4:30 pm EST | | 2384 Poster | AB-101, Outpatient-Administered, Non-Genetically Modified NK Cells in Combination with Rituximab, Demonstrates Favorable Safety Profile in a Large Cohort of 60 Patients with Rheumatological Diseases while Consistently Achieving Deep B-cell Depletion | | Presenting Author: | Subhashis Banerjee, M.D. Chief Medical Officer, Artiva Biotherapeutics | | Session: | Poster Session C: Rheumatoid Arthritis - Treatment | | Date/Time/Location: | Tuesday, November 10, 2026 at 10:30 am - 12:30 pm EST, WB1 & 2 | | 2402 Poster | High Unmet Need and Low Clinical Response Rates Among Rheumatoid Arthritis Patients Failing Two or More Classes of b/tsDMARDs: A United States Registry Analysis | | Presenting Author: | Jonathan Kay, M.D., M.A.C.R. Timothy S. and Elaine L. Peterson Chair in Rheumatology, UMass Chan Medical School | | Session: | Poster Session C: Rheumatoid Arthritis - Treatment | | Date/Time/Location: | Tuesday, November 10, 2026 at 10:30 am - 12:30 pm EST, WB1 & 2 | | / | / | Virtual Webcast Details Investors and the general public are invited to register for the webcast here. A live question-and-answer session will follow the presentation. A replay will be available for 90 days in the Investors section of Artiva's website. About Artiva Biotherapeutics Artiva is a clinical-stage biotechnology company whose mission is to develop effective, safe and accessible cell therapies for patients with debilitating autoimmune diseases. Artiva is initiating a Phase 3 registrational trial of its lead program, AlloNK(R)(also known as AB-101), for refractory rheumatoid arthritis (RA) during the second half of 2026. AlloNK is an allogeneic, off-the-shelf, non-genetically modified, cryopreserved natural killer (NK) cell therapy candidate designed to enhance antibody-dependent cellular cytotoxicity in combination with a range of therapeutic antibodies. Initial clinical data evaluating AlloNK in combination with anti-CD20 antibodies have demonstrated encouraging activity across multiple B-cell-driven autoimmune diseases and a tolerability profile supportive of outpatient administration. Artiva is developing AlloNK plus rituximab as a scalable, outpatient-administered, deep B-cell depletion treatment regimen for use in community rheumatology settings. In addition to refractory RA, AlloNK is being evaluated in Sjögren disease, systemic sclerosis and myositis. Artiva is headquartered in San Diego, California. For more information, please visit www.artivabio.com. Forward-Looking Statements This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Statements in this press release that are not statements of historical fact are forward-looking statements. Such forward-looking statements include, without limitation, statements regarding: the potential benefits, accessibility, practicality, effectiveness, safety and tolerability of AlloNK, including based on interim pooled data across clinical trials, and the potential for administration in an outpatient community setting; the registrational Phase 3 trial for AlloNK, including trial design, expectations for response rates, and timing of initiation, future updates on site activation and enrollment, and topline data readout; and Artiva's ability to generate sufficient data to support a BLA submission; clinical data expected to be presented from patients with refractory RA, SjD and SSc, and the timing of such data disclosures; the number of patients with data from the basket study who would be expected to meet the key eligibility criteria for the planned Phase 3 trial; Artiva's ability to realize the potential benefits associated with FDA RMAT designation for AlloNK; Artiva's beliefs regarding its competitive position, including its belief that AlloNK may be the first deep B-cell depleting therapy of any modality to reach patients with, and be approved and commercialized in, refractory RA; and Artiva's future results of operations and financial position, including cash runway. These forward-looking statements are based on the beliefs of the management of Artiva as well as assumptions made by and information currently available to Artiva. Such statements reflect the current views of Artiva with respect to future events and are subject to known and unknown risks and uncertainties, including, without limitation, risks and delays relating to initiation of the Phase 3 registrational trial, activation of clinical trial sites, patient enrollment and the availability and timing of disclosure of data; risks that future clinical trial results may not be consistent with interim, initial, preliminary, or topline results or results from prior preclinical studies or clinical trials, or with Artiva's expectations; the risk that the number of patients, or the duration of follow-up for such patients, available for presentation differs from current expectations; the risk that differences exist between trial designs, patient characteristics and other factors for the Phase 3 trial, Artiva-sponsored Phase 2a basket trial and investigator-initiated basket trial, and caution should be exercised in drawing any conclusions from such data across separate trials as such pooling and comparative data is inherently limited and such data may not be directly comparable; the risk that other deep B-cell depleting therapies may advance more rapidly than Artiva currently anticipates, that Artiva's assessment of publicly disclosed competitor development timelines may be incomplete or inaccurate, and that Artiva may not achieve or be the first to achieve regulatory approval or commercialization of a therapy in this category; the risk that Artiva's registrational strategy is based in part on recent interactions with the FDA and later feedback from the FDA may be inconsistent with past interactions; Artiva's ability to obtain adequate financing to fund its planned clinical trials and other expenses; risks inherent in developing product candidates; and risks related to the legal and regulatory framework for the industry. In light of these risks and uncertainties, the events or circumstances referred to in the forward-looking statements may not occur. These and other factors that may cause Artiva's actual results to differ from current expectations are discussed in Artiva's filings with the Securities and Exchange Commission (the "SEC"), including the section titled "Risk Factors" in Artiva's Quarterly Report on Form 10-Q for the quarter ended June 30, 2026. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date this press release is given. Except as required by law, Artiva undertakes no obligation to publicly update any forward-looking statements, whether as a result of new information, future events or otherwise. Investors & Media Noopur Batsha Liffick, MPH NBL LifeSci Advisory LLC [email protected]

Artiva's NK cell therapy takes FDA RMAT status for rheumatoid arthritis. June 11, 2026 San Diego-based Artiva Biotherapeutics, Inc. (Nasdaq: ARTV) announced receipt of US FDA Regenerative Medicine Advanced Therapy (RMAT) designation for AlloNK (AB-101) in combination with rituximab for refractory rheumatoid arthritis treatment, coinciding with five data presentations at the European Alliance of Associations for Rheumatology (EULAR) 2026 Congress in London. AlloNK is an allogeneic, off-the-shelf, non-genetically modified, cryopreserved natural killer (NK) cell therapy designed to enhance the antibody-dependent cellular cytotoxicity (ADCC) effect of anti-CD20 monoclonal antibodies to drive deep B-cell depletion. RMAT designation, established under the 21st Century Cures Act, applies to cell therapies, gene therapies, and tissue-engineered products intended to treat serious conditions, and confers early and frequent FDA interactions, rolling review eligibility, and potential qualification for accelerated and priority review. Artiva has not previously disclosed any other expedited designation for AlloNK. The designation is grounded in Phase II data from two basket trials - a company-sponsored Phase IIa study and an investigator-initiated trial - enrolling patients with long-standing, highly active RA who had failed multiple prior biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs). As of the April 3, 2026 data cutoff, in the company-sponsored Phase IIa trial, 71% of patients with six months of follow-up achieved an ACR50 response (5 of 7 patients). In the investigator-initiated trial, 5 of 6 patients with six months of follow-up achieved an ACR50 or modified ACR50 response. Across the pooled RA dataset of 21 patients with at least 12 weeks of follow-up, clinical responses emerged as early as three months and deepened at six months. As of the data cutoff, no patient had experienced loss of response, required high-dose steroids, or initiated a new b/tsDMARD following treatment. No p-values have been reported; all data derive from single-arm, non-randomized studies. Baseline patient characteristics reported in a May 8, 2026 data release - which contains more granular detail than the EULAR announcement - indicated a mean age of 52.5 years, 100% female, mean disease duration of 14.8 years, mean baseline Clinical Disease Activity Index (CDAI) of 50.7, mean baseline DAS28-ESR of 7.3, and 81% of patients having failed two or more prior b/tsDMARDs. Translational data from 51 evaluable autoimmune patients demonstrated uniform B-cell depletion by Day 13 following treatment with the conditioning regimen of cyclophosphamide and fludarabine, AlloNK, and rituximab. Complete B-cell depletion, confirmed by high-sensitivity assay, was observed in all 28 evaluable RA patients. B-cell reconstitution was characterized by a predominance of naïve and transitional B cells, consistent with the proposed immune reset hypothesis. Safety data from 55 autoimmune patients treated with AlloNK plus rituximab showed no cytokine release syndrome (CRS), no immune effector cell-associated neurotoxicity syndrome (ICANS), no AlloNK-related serious adverse events, and no treatment discontinuations due to adverse events. The rate of Grade 3 or higher infections was 2%. Two of 55 patients were hospitalized for treatment-emergent adverse events during the initial 28-day post-treatment period, neither deemed related to AlloNK. EULAR 2026 presentations also included initial data in Sjögren disease (SjD) and systemic sclerosis (SSc). In SjD, mean stimulated salivary flow increased from 0.65 mL/min at baseline to 1.23 mL/min at six months, with high baseline disease activity (mean ClinESSDAI 16.1, mean ESSPRI 8.0). In SSc, mean modified Rodnan skin score improved by 9.5 points at six months, all patients achieved rCRISS25, and 50% achieved rCRISS50. These indications are not covered by the RMAT designation. Artiva plans to initiate a Phase III registrational trial evaluating AlloNK plus rituximab versus rituximab alone in refractory RA in 2026, with ACR50 at six months as the primary endpoint and approximately 150 patients enrolled. The company has cited FDA alignment on this registrational strategy and stated that capital from a recent financing is expected to extend runway into 2029. Research context. Refractory RA represents a population with limited options after failure of multiple b/tsDMARDs. The current treatment landscape includes TNF inhibitors, IL-6 receptor antagonists, JAK inhibitors, and rituximab, none of which reliably produce deep, durable responses in multiply-refractory patients. The most directly competitive approach is CD19-directed CAR-T cell therapy. Early investigator-initiated data with autologous CD19 CAR-T, including work from groups at Erlangen and elsewhere, have reported sustained drug-free remissions in small numbers of RA patients, generating substantial interest in B-cell depletion as a disease-modifying strategy. However, autologous CAR-T requires patient-specific manufacturing, inpatient administration, and access to specialized centers, constraints that limit scalability. Artiva has positioned AlloNK as delivering comparable depth of B-cell depletion to CD19 CAR-T - a claim supported by the 100% complete depletion rate in evaluable patients - while using an allogeneic, off-the-shelf product that the company contends is compatible with outpatient, community rheumatology settings. Unlike autologous CAR-T, AlloNK is not genetically modified and does not carry a CD19-targeting construct; instead, it relies on enhancing the ADCC activity of co-administered rituximab to achieve B-cell killing. This distinction has implications for manufacturing scalability and the absence of CRS and ICANS in the current dataset, though the dataset remains small and non-randomized. Whether the depth and durability of B-cell depletion observed with AlloNK plus rituximab will replicate in a randomized Phase III setting, and how it will compare against the emerging autologous CAR-T data in RA, remains to be established. This article was generated with AI assistance and reviewed and edited by the AllSci editorial team Explore more at AllSci News: https://allsci.com/news/