Risdiplam is an orally bioavailable small molecule that distributes into the central nervous system (CNS) and peripheral tissues where it modifies SMN2 pre-mRNA splicing and increases tissue SMN protein levels. It was approved by the U.S. Food and Drug Administration for all SMA patients older than 2 months of age in August 2020.
Clinical trial data prompted us to consider risdiplam a reasonable alternative to nusinersen administered intrathecally or by subcutaneous intrathecal catheter (SIC) for patients with more advanced SMA. Considered within this clinical context, risdiplam presents a significant advantage by eliminating the risks of mechanical failure, intrathecal bleeding, and CNS infection associated with the SIC device. The schedule of assessments (SOAs) used in this cohort during the previous three-year period as part of a nusinersen study provide us with an established framework for data collection. Thus, the overall clinical experience with risdiplam as compared to nusinersen can be assessed using a prospective, crossover design in a real-world setting.
