Data from part 1 of the SUNFISH trial (NCT02908685), an exploratory efficacy study in children and adults with type 2 or type 3 spinal muscular atrophy (SMA), show that the risdiplam (Roche; Genentech, San Francisco, CA) treatment significantly improved motor function. This improvement was seen after 24 months of treatment and is compared with natural history data (Motor Function Measure [MFM] Scale 3.99-point difference; P<.0001).
These results are consistent with those from part 2 of the SUNFISH trial at 12 months in nonambulatory participants, which showed that the change from baseline in total MFM-32 score was significantly greater in people treated with the therapy compared with placebo (1.55-point difference; P=.0156).
The therapy is designed to increase and sustain SMN protein levels both throughout the central nervous system and in peripheral tissues of the body.
Also, preliminary 12-month data from the JEWELFISH trial (NCT03032172) of risdiplam treatement of individuals with SMA age 6 months to 60 years who were previously treated with other SMA medicines showed that risdiplam led to rapid and sustained increases in SMN protein levels.
"We continue to be highly encouraged by the positive results observed in the SUNFISH and JEWELFISH trials that further support the long-term benefits of risdiplam," said Stuart W. Peltz, PhD, chief executive officer, PTC Therapeutics. "These results are clinically meaningful with a favorable safety profile. They also reinforce the potential of risdiplam as a differentiated, oral therapy to improve motor function for children and adults with SMA. We anticipate that risdiplam will be a new and meaningful at-home treatment for a broad range of people affected by this devastating disease."
James Geyer, MD, and Paul Cox
Brad Klein, MD, MBA, FAAN, FAHS, FAANEM, and Raissa Villanueva MD, MPH, FAAN
Melissa W. Ko, MD; Kevin E. Lai, MD; and Devin D. Mackay, MD