Dive Brief:

• Kyverna Therapeutics will seek clearance of what could be the first marketed cell therapy for an autoimmune condition after the treatment succeeded in a pivotal trial in a progressive condition known as stiff person syndrome. 
• According to Kyverna, four months after treatment with its therapy miv-cel, Phase 2 study participants had a median 46% improvement from the trial’s start on a type of timed walking test. More than four-fifths had at least a 20% improvement, a threshold that’s believed to be “clinically meaningful,” Kyverna said Monday. The therapy met its key secondary study goals as well.
• Kyverna said there were no “high-grade” cases of the immune or neurological side effects associated with treatments like miv-cel. There were Grade 3 or 4 instances of neutropenia, or low counts of a kind of white blood cell, but Kyverna said they were “manageable.” Kyverna will seek U.S. approval in the first half of next year. 

Dive Insight:

Kyverna has long been a front-runner in the race to transform the types of cell therapies originally developed for cancer into autoimmune disease treatments. 

Originally formed to pursue so-called Treg cell therapy, Kyverna changed direction and licensed a more conventional cell therapy technology that’s yielded what’s now known as miv-cel. Fueled by academic studies suggesting these therapies might rewire the immune systems of people with autoimmune disorders like lupus, it raised hundreds of millions of dollars in private and public funding. But mixed early results and growing competition tempered excitement about these treatments, depressing the share price of Kyverna and many of its peers. 

Kyverna swapped CEOs and, under a new leader, began developing miv-cel for stiff person syndrome, a disorder that causes intensifying muscle stiffness. While rare, the condition has less therapeutic competition than Kyverna’s other targets and, because of its fast progression, offered a quicker path to clinical results.  

Since then, Kyverna has begun clawing back some of its stock value and quickly completed enrollment in a registrational trial. Its goal in the 26-patient study was for miv-cel to help drive at least a 20% change on a timed, 25-foot walking test. Executives had pointed to case reports suggesting miv-cel could produce more powerful effects.

According to Leerink Partners analyst Thomas Smith, the results announced Monday are a “best-case scenario” for Kyverna, enabling the company to bring to market the first and only therapy for stiff person syndrome as well as, more broadly, the first approved cell therapy for autoimmune disease. In addition to clearing the important walking test threshold, miv-cel also helped many patients no longer need a walking device after 16 weeks and, so far, has freed all study participants from the immunotherapies typically used to treat their condition. 

“We believe this highlights miv-cel's potential to provide unprecedented clinical benefit, while significantly reducing or eliminating chronic treatment burden,” Smith wrote. 

Kyverna will provide detailed study results at a medical meeting next year. Company shares climbed by more than 25% in early Monday trading.