Kyverna CAR-T gains in stiff person syndrome hold at one year

Kyverna Therapeutics reported one-year results on 24 September 2026 for miv-cel (KYV-101), a fully human, autologous CD19-targeting CAR T-cell therapy given as a single dose to reset the immune system in autoimmune disease.

In the registrational KYSA-8 trial, 26 adults with stiff person syndrome, a rare autoimmune disorder that locks muscles in painful spasms, received the therapy. Their time on the timed 25-foot walk improved by a median 46% at week 16 and 49% at month 12. Of the 12 patients who needed a walking aid before treatment, 67% no longer used one at a year, and 92% of all patients remained free of chronic immunotherapy for the disease.

In the Phase 2 KYSA-6 study, all seven patients with generalized myasthenia gravis reached a clinically meaningful improvement on the MG-ADL and QMG scales at 24 weeks. Neither trial recorded high-grade cytokine release syndrome or immune effector cell-associated neurotoxicity. Kyverna says its rolling Biologics License Application for stiff person syndrome is on track to be completed in the fourth quarter of 2026, and that Phase 3 enrollment in myasthenia gravis should finish by mid-2027.