FDA grants priority review for SMA drug in infants younger than 2 months

The FDA has granted priority review to PTC Therapeutics Inc. for a supplemental new drug application regarding Evrysdi, according to a company release.

Evrysdi (risdiplam; Genentech, Roche Group), which was recently approved by the FDA for treatment of spinal muscular atrophy in adults and children aged 2 months and older, is now under review to include pre-symptomatic infants younger than 2 months. If approved, risdiplam would be the first medication approved for in-home use to treat pre-symptomatic babies with SMA.

“The results demonstrating that almost all of the pre-symptomatic infants achieved motor milestones comparable to healthy infants is tremendous,” Stuart W. Peltz, PhD, chief executive officer at PTC Therapeutics, said in the release. “The granting of the priority review for Evrysdi recognizes this and the significant need to treat babies with SMA as early as possible. We are proud that such a transformative treatment for patients living with SMA came from our splicing platform.”

The FDA based the priority review designation on interim data derived from RAINBOWFISH, an open-label, single-arm, multicenter study examining the efficacy, safety, pharmacokinetics and pharmacodynamics of risdiplam in pre-symptomatic patients from birth to 6 weeks who have genetically diagnosed SMA.

Results showed 80% of pre-symptomatic infants with SMA treated with risdiplam for at least 1 year were able to reach developmental landmarks appropriate for the age group, including sitting without support, rolling, crawling and unaided standing and walking.

Risdiplam is designed to treat SMA by increasing and maintaining production of the SMN protein, which is crucial to maintain healthy motor neurons and proper movement. The Roche Group leads the clinical development of risdiplam as part of a collaboration between the SMA Foundation and PTC Therapeutics.