Risdiplam Treatment Results in Sustained Motor Function Improvement for Individuals with Spinal Muscular Atrophy

The second part of the SUNFISH trial (NCT02908685) evaluated risdiplam (Evrysdi; PTC Therapeutics, South Plainfield, NJ) in children and adults with type 2 or type 3 spinal muscular atrophy (SMA). The participants in the study sustained or improved motor function after 24 months of risdiplam treatment as well as independentlymaintaining or gaining the ability to complete daily tasks. Risdiplam is designed to treat SMA by increasing and sustaining the production of the SMN protein. 

"We're encouraged by the long-term results from the SUNFISH trial, which reinforce the sustained clinical benefit that Evrysdi offers to a very broad population of patients with SMA, many of whom experience difficulty performing daily functions," said Stuart W. Peltz, PhD, chief executive officer, PTC Therapeutics. "These data further support the strong US launch and the need for an at home oral treatment option for the SMA community."

Data from SUNFISH Part 2 include efficacy and safety data in the overall population for 2 years as follows.

•    Motor function as measured by the  -32 (MFM32), revised upper limb module (RULM) and Hammersmith functional motor scale expanded (HFMSE) was improveed or maintained
•    Motor function improvements between months 12 and 24 as measured by MFM-32 were maintained
•    Motor function for participants who started treatment with risdiplam after 12 months of placebo, as measured by MFM-32, RULM and HFMSE was stabilized
•    Upper limb use improved, as measured by the caregiver reported SMA Independence Scale (SMAIS) upper limb module

During the study, a decrease in serious adverse events, high-grade adverse events and treatment-related adverse events was observed. The most common adverse events observed were upper respiratory tract infection, nasopharyngitis, pyrexia, headache, diarrhea, vomiting and cough. The most common serious adverse events were pneumonia and influenza.