New Data Shows Evrysdi Helps Children With SMA Achieve Independent Mobility

At the 29th World Muscle Society (WMS) Congress, held from October 8-12, 2024, Genentech, part of the Roche Group, shared encouraging two-year data from the RAINBOWFISH study. This ongoing trial evaluates the safety and efficacy of Evrysdi® (risdiplam) in infants diagnosed with SMA who began treatment before six weeks of age (sample size: 23). The results revealed that most children met significant motor milestones, maintained the ability to swallow and feed orally, and exhibited cognitive development on par with typical children of the same age, with none requiring continuous ventilation.

Among the children with three or more copies of the SMN2 gene (n=18), all reached the milestones for standing and walking (100%) as measured by the Bayley Scales of Infant and Toddler Development, Third Edition (BSID-III) and the Hammersmith Infant Neurological Examination, Module 2 (HINE-2). Remarkably, most achieved these milestones within the normal developmental timelines established by the World Health Organization (WHO).

In the group of children with two SMN2 gene copies (n=5), all were able to sit independently (100%), and the majority (60%) achieved independent standing and walking milestones after two years of Evrysdi treatment. Additionally, every child was able to swallow and feed orally, with no instances of permanent ventilation needed. According to natural history data, without treatments that modify the disease, children with Type 1 SMA typically do not reach these milestones and rarely live beyond age two.

Two years into Evrysdi treatment, children in the study displayed cognitive abilities comparable to their peers without SMA, as evaluated by the Cognitive Scale of the BSID-III. Notably, this study was the first SMA clinical trial to incorporate a standardized cognitive assessment as an exploratory measure.

In this study, infants began receiving Evrysdi treatment before reaching six weeks of age, with the first dose administered at a median age of 25 days. Researchers aimed to assess the outcomes of early treatment initiation prior to symptom onset by comparing results based on each child’s SMN2 gene copy number. Typically, children with fewer SMN2 copies face a more severe form of SMA.

Throughout the study, there were no fatalities or adverse events (AEs) that led to treatment discontinuation or withdrawal. Common AEs included teething, gastroenteritis, diarrhea, eczema, and fever. The adverse events seen in this second-year analysis are generally aligned with those reported in other Evrysdi trials for SMA and appeared to correlate more with the children’s age than with SMA itself. Most AEs were not deemed related to the treatment and resolved naturally over time. The clinical development of Evrysdi is led by Genentech in partnership with the SMA Foundation and PTC Therapeutics.

Laurent Servais, M.D., Ph.D., Professor of Paediatric Neuromuscular Diseases at the MDUK Oxford Neuromuscular Centre, said in a statement, “In children with SMA, motor neuron degeneration starts before the onset of symptoms, so time is of the essence if we hope to preserve muscle function. It’s heartening to see that through early intervention with Evrysdi these children have achieved important milestones like sitting, standing and walking that would typically be unattainable without treatment.” 

Levi Garraway, M.D., Ph.D., Genentech’s chief medical officer and head of Global Product Development, said in a statement, “These 2-year findings confirm the potential of early intervention with Evrysdi to meaningfully improve the lives of children with SMA. Working in tandem with newborn screening programs, Evrysdi is the only non-invasive SMA treatment that can be administered during a child’s first hours of life.”