October 04, 2023
Evrysdi's new data demonstrated that 80% of infants with SMA could sit for five seconds or more after one year.
The RAINBOWFISH study has yielded promising results regarding treating spinal muscular atrophy (SMA) in newborns using Roche's Evrysdi. After one year of treatment, many infants demonstrated the ability to sit independently, a milestone previously unattainable without this intervention.
This study's primary objective was met, which included 26 pre-symptomatic SMA infants aged from birth to six weeks. Approximately 80% of infants with two or more copies of the SMN2 gene (a marker of disease severity) could sit unsupported for at least five seconds after one year of Evrysdi treatment. This assessment used the Bayley Scales of Infant and Toddler Development (BSID-III). Generally, a lower number of SMN2 copies implies a more severe form of SMA.
Furthermore, the study revealed that 81% of infants could independently sit for 30 seconds, and many were progressing towards standing and walking. This motor function improvement is noteworthy, especially considering that children with Type 1 SMA typically do not achieve independent sitting without intervention.
The RAINBOWFISH study also explored cognitive development using the BSID as an exploratory endpoint, showing that infants exhibited cognitive skills within the expected range of normal child development after one year of Evrysdi treatment.
Regarding safety, adverse events (AEs) noted during the study were generally linked to the age of the infants rather than the underlying SMA condition. Most AEs were not considered treatment-related, and no deaths or AEs necessitating treatment discontinuation occurred. Common AEs included teething, COVID-19, pyrexia, gastroenteritis, eczema, and constipation, consistent with AEs seen in other Evrysdi trials in SMA.
It's important to note that Evrysdi, a non-invasive SMA therapy, is approved in over 100 countries and has been administered to more than 11,000 patients globally. This treatment is particularly significant because it offers hope to infants with SMA, even before symptoms appear, underscoring the importance of early intervention in enhancing outcomes.
In addition to the RAINBOWFISH study, Roche is also exploring the potential of Evrysdi in combination with an anti-myostatin molecule to promote muscle growth in SMA patients aged 2-10 years in the Phase 2/3 MANATEE trial, which represents a promising avenue for further advancing SMA treatment options.