Kyverna Therapeutics Updates COMPARE Trial Data

Kyverna Therapeutics announced the presentation of updated data from the Phase 1 portion of COMPARE, a Phase 1/2 investigator-initiated trial evaluating miv-cel in patients with active anti-citrullinated protein antibody-positive, treatment-refractory rheumatoid arthritis. The data will be presented today in an oral presentation by Charite - University of Berlin at the European Alliance of Associations for Rheumatology, or EULAR, 2026 Congress in London. Building on the safety and efficacy results reported at ACR Convergence 2025, the updated data showed a single dose of miv-cel resulted in deep B-cell depletion with subsequent reconstitution with a naive B-cell phenotype in ACPA-positive RA patients. These findings demonstrate the potential of an immune reset and translate into meaningful clinical improvement. The COMPARE trial is an open-label, randomized, controlled Phase 1/2 study evaluating miv-cel against the anti-CD20 monoclonal antibody rituximab in patients with active ACPA-positive, treatment-refractory RA with moderate to high disease activity. All six patients enrolled in the Phase 1 portion of the study displayed highly refractory disease and had failed a median of 6.5 prior biologic and targeted synthetic disease-modifying anti-rheumatic drugs before entering the study. Patients received a single infusion of 1108 miv-cel CAR T cells following lymphodepletion with follow-up ranging up to 52 weeks. The primary endpoint for the Phase 1 study was safety and tolerability with patients additionally evaluated for efficacy and key biomarkers of RA. Deep depletion of autoreactive CD19+ B cells and plasmablasts in periphery and tissues. Rapid and substantial reduction in disease-associated autoantibodies, including ACPA, rheumatoid factor immunoglobulin A and M, for up to 52 weeks, while preserving long-term protective vaccine immunity. Substantial reduction in disease activity in all six patients who showed fewer tender and swollen joints and less joint inflammation following a single dose of miv-cel. In addition, the majority of patients met the ACR70 response by Week 36. Evidence of immune reset with repopulated B-cells returning as predominantly naive and transitional cells. Well-tolerated safety profile with no high-grade cytokine release syndrome and no immune effector cell-associated neurotoxicity syndrome. Based on the Phase 1 findings, the Phase 2 portion of the COMPARE trial has been initiated and is fully enrolled. This trial compares B-cell depletion with miv-cel versus rituximab in patients with active ACPA-positive, treatment refractory RA with moderate to high disease activity.