Risdiplam Treatment of Type 1 Spinal Muscular Atrophy in Infants Has Long-Term Benefit

New 3-year data from the FIREFISH study (NCT02913482) reinforce long-term efficacy and safety of risdiplam (Evrysdi; Genentech, South San Francisco, CA) for treatment of symptomatic type 1 spinal muscular atrophy (SMA) in infancy. Approximately 91% (53/58) of infants treated with risdiplam have survived and continue having improved or maintained motor functions, including swallowing, sitting or standing without support, and walking with support. 

Infants treated with risdiplam maintained or continued to improve in their ability to sit without support between 24-36 months. Among the infants with an available assessment (n=48) treated with risdiplam, 32 maintained and 4 gained the ability to sit without support for at least 5 seconds since month 24, as assessed by the Gross Motor Scale of the Bayley Scales of Infant and Toddler Development Third Edition (BSID-III). 

“These long-term results in babies treated with Evrysdi are very encouraging, with the vast majority improving or maintaining motor functions after 3 years,” said Levi Garraway, MD, PhD, chief medical officer, head of global product development, Genentech. “Without treatment, they would typically not survive beyond 2 years of age. Support for the compelling efficacy of Evrysdi continues to grow for a broad range of people, including infants with one of the most severe forms of SMA.”

The most common adverse events (AEs) were pyrexia (60%), upper respiratory tract infection (57%), pneumonia (43%), constipation (26%), nasopharyngitis (24%), diarrhea (21%), rhinitis (19%), vomiting (19%), and cough (17%). The most common serious adverse events (SAEs) were pneumonia (36%), respiratory distress (10%), viral pneumonia (9%), acute respiratory failure (5%), and respiratory failure (5%).