Kyverna Therapeutics is preparing to submit its CAR T cell therapy, mivocabtagene autoleucel (miv-cel), for approval to the Food and Drug Administration in the first half of 2026. The company aims for miv-cel to become the first CAR T therapy approved specifically for an autoimmune disease.
Kyverna began developing miv-cel after licensing it from the National Institutes of Health in January 2022, focusing on B cell-driven autoimmune diseases. Early preclinical research suggested that miv-cel offered potency, durability, and improved safety compared with existing cell therapies used in lymphoma. According to analysts from William Blair, this decision positioned Kyverna ahead as data emerged supporting cell therapy's use beyond oncology.
The company's initial target is stiff person syndrome (SPS), a rare disorder affecting approximately 6,000 people in the United States and characterized by muscle rigidity and severe spasms. There are currently no specific treatments approved for SPS; about 80% of patients progress to disability requiring mobility aids such as walkers or wheelchairs. In Kyverna’s Phase 2 clinical trial, two-thirds of participants who previously relied on mobility aids were able to walk without them following treatment with miv-cel. Patients also discontinued background immunosuppressant medications after receiving the one-time therapy.
Chief Executive Officer Warner Biddle said at a recent industry convention, "sometimes being smaller and being nimble and being able to focus allows you to start to accelerate." He added that many patients continue showing strong results two years after participating in Kyverna’s trial: “In a way we’re providing this tremendous clinical benefit for patients, but we’re also changing the paradigm of how autoimmune diseases are being managed, which we’re really proud to be a part of and leading.”
After SPS, Kyverna plans further trials targeting generalized myasthenia gravis—a larger market where other companies like Amgen, Johnson & Johnson, AstraZeneca and argenx already have approved therapies—and progressive multiple sclerosis. However, Biddle said current treatments only provide modest improvements: “All the treatments that are managing and approved for this indication right now aren’t doing what we’re doing with miv-cel.” He pointed out that their Phase 2 trial brought patients closer to minimal symptom expression than existing drugs.
