Bioavailability and Bioequivalence of Two Risdiplam Tablets in Healthy Participants

Part 1 of the study is an exploratory comparison of the relative oral bioavailability of the two dispersible tablets versus risdiplam powder for oral solution as the reference. The effect of food on the bioavailability of the two dispersible tablets will be assessed by comparing fed and fasted states in a five-way crossover manner. It will also be assessed whether antacids (omeprazole) have an impact on the bioavailability of the dispersible tablets in a two-way crossover manner. The food effect on the risdiplam oral solution will also be assessed by comparing fed and fasted states in a two-way crossover manner. In Part 2, based on the data obtained in Part 1 and provided data support further evaluation, a bioequivalence assessment and a food-effect evaluation will be conducted in two groups with the selected dispersible tablet formulation. Each group will randomly receive, in a four-way crossover, a single dose of risdiplam oral solution 5 mg in both fed and fasted states, and a single dose of the selected dispersible tablet in both fed and fasted states. In Part 3, provided Part 1 data support further evaluation of the second formulation, the second formulation may be assessed for bioequivalence in the same way as described in Part 2. Enrollment of the same participant in more than one cohort or group will not be permitted regardless of the study part.