FDA Approves Itvisma for Spinal Muscular Atrophy

MONDAY, Dec. 8, 2025 (HealthDay News) — The U.S. Food and Drug Administration has approved Itvisma (onasemnogene abeparvovec-brve) for the treatment of spinal muscular atrophy (SMA) in patients 2 years and older with confirmed mutation in the survival motor neuron 1 (SMN1) gene.

Itvisma, an adeno-associated virus vector-based gene therapy, is administered with a one-time, fixed-dose intrathecal injection that does not need to be adjusted for age or body weight.

The approval was based on data from the registrational phase 3 STEER study and the open-label phase 3b STRENGTH study, which showed statistically significant improvements in motor function and stabilization of motor abilities typically not seen in the natural history of the disease. Effects were sustained over 52 weeks of follow-up. The most common adverse events in the STEER study were upper respiratory tract infection and pyrexia, and in the STRENGTH study, the most common adverse events were common cold, pyrexia, and vomiting.

“The FDA”s approval of intrathecal onasemnogene abeparvovec is a game-changing advance, expanding the use of transformational gene replacement therapy for SMA across age groups,” John W. Day, M.D., Ph.D., from Stanford University in California, said in a statement. “This achievement is not only a significant step forward for SMA — it also signals new possibilities for the broader field of neurological disorders and genetic medicine.”

Approval of Itvisma was granted to Novartis.

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