First in Human SAD/MAD Safety and PK Study With Adult DMD Safety and PK Cohort

This is a first-in-human (FIH), Phase 1 study of orally administered SAT-3247 in healthy volunteers (HVs) and adult participants with DMD. The study will be conducted in 4 parts.

Part A is a Single Ascending Dose (SAD) part that will enroll approximately 40 HVs in up to 5 dose cohorts. Each participant will receive a single oral dose of SAT 3247 or matched placebo on Day 1; each cohort will receive a higher dose than the prior cohort. Part B is a Multiple Ascending Dose (MAD) part that will enroll approximately 32 HVs in up to 4 sequential dose cohorts. Each participant will receive a daily oral dose of SAT-3247 or matched placebo on Day 1 to Day 7 each cohort will receive a higher dose than the prior cohort. Part C will assess the effect of food on the PK of SAT-3247 in a fixed sequence, crossover design. The dose to be tested will be determined by the Safety Review Committee (SRC) following review of safety, tolerability, and available PK and PD data from Part A. Approximately 8 healthy participants who completed Part A at the anticipated dose level (in a fasted state) will crossover into a subsequent fed cohort and receive a single dose of the same randomized IP at the same dose level that they received in Part A but, following a high fat meal. Part D is a open-label Multiple Dose cohort that will comprise 10 adult males with genetically confirmed DMD. Each participant will receive SAT-3247 once daily for 5 consecutive days of each of 4 weeks