Kyverna's CAR T Therapy Shows Promising Results in Myasthenia Gravis, Advancing Autoimmune Applications

Kyverna Therapeutics has reported groundbreaking results from its Phase II study of KYV-101, a CAR T cell therapy for generalized myasthenia gravis (gMG), setting a new efficacy standard in the field and potentially revolutionizing treatment for this debilitating autoimmune condition.

100% Response Rate in Phase II Trial

In a significant development for both Kyverna and the broader field of autoimmune therapeutics, the company announced a 100% response rate in patients treated with KYV-101. The Phase II portion of the KYSA-6 study, involving six patients with moderate to severe gMG who had previously failed immunosuppressant therapies, demonstrated clinically meaningful improvements in activities of daily living at 36 weeks post-treatment.

All treated patients met the criteria for treatment response, defined as at least a 3-point reduction in two disease inventories. This level of efficacy has been described by analysts at William Blair as establishing "a new efficacy standard in the field," positioning KYV-101 as a potentially game-changing therapy compared to current treatments and other late-stage assets.

Reduced Treatment Burden and Safety Profile

Beyond its remarkable efficacy, KYV-101 showed promise in reducing the overall treatment burden for gMG patients. All participants in the study were able to discontinue non-steroidal immunosuppressants, high-dose steroids, and other therapies after 24 weeks of treatment with KYV-101.

The safety profile of KYV-101 appears favorable, with the therapy being well-tolerated overall. Notably, there were no documented cases of high-grade cytokine release syndrome or immune effector cell–associated neurotoxicity syndrome, which are common concerns with CAR T therapies. One patient developed grade 4 neutropenia, which was expected and improved to grade 1 by the data cutoff.

Advancing to Phase III and Broader Implications

With these promising results, Kyverna is poised to move forward with the Phase III portion of the KYSA-6 study. Chief Medical and Development Officer Naji Gehchan stated that the company expects to begin enrollment by the end of this year, marking a significant step towards potential regulatory approval.

The success of KYV-101 in gMG has broader implications for the application of CAR T therapies in autoimmune diseases. Traditionally associated with cancer treatment, CAR T technology is now showing potential in treating a range of autoimmune conditions. Other companies, including Cabaletta Bio, Bristol Myers Squibb, CRISPR Therapeutics, and Autolus Therapeutics, are also exploring CAR T platforms for various autoimmune indications.

As the pharmaceutical industry continues to expand the applications of cell therapies beyond oncology, Kyverna's success with KYV-101 in myasthenia gravis represents a significant milestone. The ongoing development of this therapy, along with similar efforts by other companies, could herald a new era in the treatment of autoimmune diseases, offering hope to patients who have exhausted conventional treatment options.