Evrysdi for Infants Under 2 Months Old Given FDA Priority Review
The U.S. Food and Drug Administration (FDA) is giving priority review to a request that the oral therapy Evrysdi (risdiplam) be approved to treat pre-symptomatic infants with spinal muscular atrophy (SMA) who are less than 2 months old.
Priority review is given to therapies with the potential to substantially improve care for serious diseases. The designation means that the FDA will devote extra resources to speed the review process, so the application will be reviewed in about six months rather than the standard 10.
“Treating very young babies with Evrysdi before SMA symptoms arise may help them to achieve milestones such as standing and walking within timeframes typical of healthy infants,” Levi Garraway, MD, PhD, said in a press release.
Garraway is chief medical officer and head of global product development at Genentech (a subsidiary of Roche), which is continuing to develop Evrysdi in collaboration with PTC Therapeutics and the SMA Foundation.
Evrysdi works to increase levels of the SMN protein, deficits in which cause SMA. It was approved in the U.S. in 2020 to treat adults and children ages 2 months and older with all SMA types, becoming the third disease-modifying SMA therapy to gain FDA approval since 2016, and its first oral and at-home treatment.
According to Roche, Evrysdi is currently available in more than 70 countries, and over 4,500 people have been treated with the medication.
“Extending treatment access for the youngest members of the SMA community is crucial and we look forward to working with the FDA on this application,” Garraway said.
The request for an extension to cover infants younger than 2 months — called a supplemental new drug application — is supported by data from the ongoing and open-label RAINBOWFISH (NCT03779334) clinical trial.
This Phase 2 study is evaluating Evrysdi in up to 25 babies with genetically confirmed SMA but no evident disease symptoms, and who have not received any other disease treatments. Newborns up to 6 weeks old are actively being recruited at sites in the U.S., Brazil, China, Italy, Poland, Saudi Arabia, and Taiwan.
Data from the first five children treated for at least one year in RAINBOWFISH were presented at a conference last year. All five maintained the ability to swallow and to be fed by mouth, and all met motor milestones for head control, sitting upright, rolling, and crawling. Four of these children were also able to stand and walk independently within developmentally typical time frames.
“The results demonstrating that almost all of the pre-symptomatic infants achieved motor milestones comparable to healthy infants is tremendous,” said Stuart Peltz, PhD, CEO of PTC Therapeutics, said in a separate press release.
Safety data to date on 12 babies dosed in RAINBOWFISH have been largely positive, with no serious side effects related to the treatment reported.
The most common adverse events recorded so far are nasal congestion (33%), cough (25%), teething (25%), vomiting (25%), eczema or red and inflamed skin (17%), abdominal pain (17%), diarrhea (17%), stomach inflammation (17%), papule or solid pimples (17%), and fever (17%). According to Roche, these events are likely not related to treatment with Evrysdi or to SMA, being “reflective of the age” of these infants.
“The granting of the Priority Review for Evrysdi recognizes … 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,” Peltz said.
Further RAINBOWFISH findings are expected to be reported at the Muscular Dystrophy Association (MDA) Clinical and Scientific Conference set for March, Roche noted.