Last week also at Myology 2019 conference Roche shared early observations from Sunfish Part I clinical trial of risdiplam.
The Sunfish trial commenced in autumn 2016. Part I enrolled 51 participants with SMA types 2 and 3, aged 2 to 25 years. A third of them were administered placebo for 12 weeks before being switched to risdiplam. The data below does not include the placebo period.
Risdiplam was shown to double the SMN protein level within 4 weeks of first administration. Continuous treatment sustained that higher concentration. After 12 months of treatment, all participants improved by an average of 2.5 points on the MFM scale. Improvement was stronger in participants below 12 years (mean of 3.3 points MFM) as compared to older participants (mean of 1.4 points). Median improvement was 4.2 points for younger participants and 2.1 points for the older group (3.1 points for the entire cohort).
Overall, after 12 months of risdiplam treatment 63% participants experienced an improvement of at least 3 points MFM. As expected, the number of improvers was higher in the younger group (77%) than in the older group (46%).
Part II of Sunfish trial is ongoing and results are expected in late 2020.