By Rob Curran

Kyverna Therapeutics' stock was higher before the market's open after a treatment for a rare neurological condition showed promise in a mid-stage clinical trial.

Shares of Kyverna were up 20% at $11.68 in premarket trading.

The Emeryville, Calif., biotechnology company said its mivocabtagene autoleucel, or KYV-101, product was tested on patients with stiff person syndrome in a phase II trial. After 16 weeks on the treatment, the majority of the 26 patients with the autoimmune condition regained function and one-third of them were able to walk at a typical adult speed.

"We see compelling evidence that a one-time therapy can reset the immune system, reverse the course of disease, and free patients from lifelong treatment burden," said Chief Executive Warren Biddle, in a statement.

Canadian singer Celine Dion suffers from stiff person syndrome and supports research into the neurological condition. The lead investigator for the trial, Dr. Amanda Piquet, is the Celine Dion Foundation endowed chair and the director of autoimmune neurology at the University of Colorado Anschutz School of Medicine.

Write to Rob Curran at rob.curan@dowjones.com

(END) Dow Jones Newswires

April 22, 2026 06:35 ET (10:35 GMT)

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