The U.S. FDA has approved Itvisma, Novartis’ newest gene replacement therapy for spinal muscular atrophy (SMA), marking a significant expansion of treatment options for people living with this rare and life-limiting genetic disorder. SMA is caused by a missing or mutated SMN1 gene, which results in insufficient levels of a protein essential for basic muscle function – including breathing, swallowing and movement. It remains the leading genetic cause of infant mortality, with an estimated 9,000 people in the United States currently living with the condition.
Itvisma is approved for patients aged two years and older, filling a key therapeutic gap. Until now, Novartis’ earlier therapy Zolgensma has been available only for children under two. While both therapies replace the SMN1 gene using the same active ingredient, their delivery differs: Zolgensma is administered intravenously and dosed according to body weight, whereas Itvisma is a concentrated formulation delivered directly into the central nervous system via the spinal cord, eliminating the need for weight-based adjustment. This distinction not only broadens the eligible population but also simplifies dosing and may offer more predictable administration for older children.
In a late-stage trial, treatment with Itvisma led to a statistically significant 2.39-point improvement on a recognised motor-function and disease-progression scale – an important indicator of clinical benefit in a condition where muscle decline can be rapid and severe.
The therapy’s wholesale acquisition cost is $2.59 million, slightly higher than Zolgensma’s $2.5 million price, continuing the trend of ultra-premium pricing in line with other one-time gene therapies. Yet Novartis emphasises that these therapies have the potential to reduce or even eliminate the need for chronically administered SMA treatments, which can accumulate substantial lifetime costs.
With Itvisma now available for a broader age group, many families who were previously excluded now have access to a transformative treatment option. This approval marks an important step in widening access to gene replacement therapies for this rare neuromuscular disease.
