Kyverna's miv-cel shows durable one-year benefit in stiff person syndrome and myasthenia gravis

US immunology company Kyverna Therapeutics (Nasdaq: KYTX) has reported positive one-year topline data from its registrational KYSA-8 trial of miv-cel (mivocabtagene autoleucel, KYV-101) in stiff person syndrome (SPS), alongside longer-term Phase II follow-up from its KYSA-6 trial in generalized myasthenia gravis (gMG).

In KYSA-8, a single-arm trial of 26 adults with SPS who had inadequately responded to prior immunotherapy, median improvement in the timed 25-foot walk reached 49% at month 12, with 95% of patients who achieved a clinically meaningful response at the primary analysis sustaining that benefit. Of 12 patients who needed a walking aid before treatment, 67% no longer required one, and 92% remained free of chronic SPS immunotherapies at 12 months. No high-grade cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, or IEC-HS was reported.