Itvisma is uniquely designed to address the genetic root cause of spinal muscular atrophy with a one-time fixed dose that does not need to be adjusted for age or body weight. By replacing the SMN1 gene, Itvisma can improve motor function, offering the potential to reduce the need for chronically administered treatment associated with other available therapies for this population.
“The FDA’s approval of intrathecal onasemnogene abeparvovec is a game-changing advance, expanding the use of transformational gene replacement therapy for
spinal muscular atrophy across age groups,” said John W. Day, MD, PhD, Professor of Neurology and Pediatrics, Director, Division of Neuromuscular Medicine at Stanford University School of Medicine, and Co-Director of Stanford’s Neuro IGNITE Center. “This achievement is not only a significant step forward for
spinal muscular atrophy – it also signals new possibilities for the broader field of neurological disorders and genetic medicine.”
The approval of Itvisma is based on data from the registrational Phase lll STEER study and supported by the open-label Phase lllb STRENGTH study. Itvisma showed statistically significant improvements in motor function and stabilization of motor abilities typically not seen in the natural history of the disease, with effects sustained over 52 weeks of follow-up. Additionally, Itvisma demonstrated a safety profile with adverse events that were consistent across both studies. These data were presented at the 2025 Muscular Dystrophy Association (MDA) Clinical and Scientific Conference.
“This new route of administration for a single dose of gene replacement therapy can mean so much more than what is measured by numbers on a functional motor scale – it could mean greater independence and freedom in activities of daily life,” said Kenneth Hobby, President, Cure SMA. “The
spinal muscular atrophy disease landscape has dramatically changed over the last six years, when the first gene therapy was approved. This is another welcome advancement, and it represents real progress in expanding access for many older patients and addressing the unmet needs that remain in our community.”
Spinal muscular atrophy is a rare, genetic neuromuscular disease caused by a mutated or missing
SMN1 gene. The
SMN1 gene is responsible for producing most of the SMN protein a body needs for muscle function, including breathing, swallowing and basic movement. Without it, motor neurons are irreversibly lost, leading to progressive, debilitating muscle weakness. A second gene, the
SMN2 gene, produces a small fraction (~10%) of functional SMN protein compared with the
SMN1 gene. Individuals with more copies of the
SMN2 gene generally have a less severe form of
spinal muscular atrophy than those with fewer copies.
Approximately 9,000 people in the US live with
spinal muscular atrophy, and though there have been advancements in treating the disease, unmet needs remain for older children, teens, and adults in preserving motor neurons and maintaining physical strength.
“After redefining spinal muscular atrophy care with the first gene replacement therapy for this challenging disease, we can now help address unmet needs across an even broader spinal muscular atrophy population with the approval of Itvisma," said Victor Bultó, President, Novartis, US. “We are proud to support the spinal muscular atrophy community by empowering patients of all ages through our innovative, one-time therapies, offering the potential to reduce the burden that comes with chronic treatment.”
Disclaimer: This website is primarily for healthcare professionals. The content here does not replace medical advice and should not be used as medical, diagnostic, endorsement, treatment, or prescription advice. Medical science evolves rapidly, and we strive to keep our information current. If you find any discrepancies, please contact us at corrections@medicaldialogues.in. Read our Correction Policy here. Nothing here should be used as a substitute for medical advice, diagnosis, or treatment. We do not endorse any healthcare advice that contradicts a physician's guidance. Use of this site is subject to our Terms of Use, Privacy Policy, and Advertisement Policy. For more details, read our Full Disclaimer here.
NOTE: Join us in combating medical misinformation. If you encounter a questionable health, medical, or medical education claim, email us at factcheck@medicaldialogues.in for evaluation.