Kyverna reports one-year mobility gains and safety for CAR-T miv-cel in stiff-person syndrome, bolstering FDA filing plans

Kyverna Therapeutics presented data from its Phase 2 KYSA-8 trial of miv-cel, a CAR-T therapy aimed at stiff-person syndrome (SPS). The study followed 26 patients for one year.

At the one-year mark, participants showed notable improvements in mobility and leg function, effectively reversing the typical decline seen in SPS. The safety profile remained favorable, with no new safety concerns reported.

These results meet the trial's primary endpoints and are expected to strengthen Kyverna's upcoming priority-review filing with the FDA later this year. The positive readout comes as other companies have paused autoimmune CAR-T programs after safety issues.

Analysts at William Blair said the durability data further de-risk the regulatory path, positioning Kyverna to potentially achieve the first FDA approval for a CAR-T therapy in an autoimmune disease.