Kyverna touts one-year durability data for autoimmune CAR-T

Kyverna Therapeutics announced positive one-year topline data from its registrational trial of miv-cel in patients with stiff person syndrome, and positive topline longer-term follow-up data from the phase 2 portion of a registrational trial in patients with generalized myasthenia gravis.

Miv-cel is an autologous, CD19-targeting CAR-T cell therapy with CD28 co-stimulation, designed for potency and tolerability.

In the KYSA-8 stiff person syndrome (SPS) trial, primary and all key secondary endpoints were achieved with statistical significance, with one-year data showing sustained benefit. As of the July 2026 database lock, 26 patients with SPS had completed 12-month follow-up, with median timed 25-Foot Walk (T25FW) improvement sustained at 49% from baseline; 95% of patients who achieved a clinically meaningful improvement at the primary analysis maintained that benefit. Among 12 patients who required a walking aid before treatment, 67% remained independent at 12 months, while 92% remained free of chronic immunotherapy. Secondary endpoint improvements were also sustained, and miv-cel remained well tolerated, with no high-grade CRS, ICANS or IEC-HS reported.

Longer-term data in the KYSA-6 trial in myasthenia gravis also showed durable responses following a single dose of miv-cel. All seven patients achieved clinically meaningful improvements in Myasthenia Gravis Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) at 24 weeks. Improvements in MG-ADL, QMG and MGC scores were sustained for at least one year in all five patients who reached that time point, while 57% maintained minimal symptom expression. All seven patients remained free of immunotherapy at 24 weeks, with six still off immunosuppressants at last follow-up.

Kyverna intends to include the one-year data in its rolling BLA submission, first initiated in May and on track to be completed in Q4 2026.

Kyverna's good news comes less than a month after Novartis and BMS paused multiple trials of their investigational CAR-T therapies in autoimmune diseases due to patient deaths and other safety concerns.