Kyverna Therapeutics reported positive primary-analysis results from its registrational Phase II trial KYSA-8 of mivocabtagene autoleucel (miv-cel, KYV-101) in stiff-person syndrome. The company presented the data as a potential step toward a first-in-class CAR T in an autoimmune indication. The trial design centers on a single dose intended to avoid chronic immunotherapy and address disease progression in a population where current options are limited. Kyverna reported statistically significant improvements across primary and secondary endpoints at 16 weeks, with a majority of patients regaining function and all stopping chronic immunotherapies. The update also included tolerability commentary, supporting the case for continued development and regulatory submission timing. Kyverna said it plans to submit a BLA to the FDA in the first half of the year. For the autoimmune-cell-therapy field, the key watch item is whether the efficacy and safety signal holds up as Kyverna moves from registrational trial execution toward submission-level data expectations.