Background: SAT-3247 is an investigational, small molecule inhibitor of adaptor-associated protein kinase (AAK1) that has been shown to increase asymmetric stem cell division, muscle progenitor formation, and muscle fiber regeneration that is impaired due to an absence of dystrophin. TRAILHEAD (NCT06867107) is an open-label, Phase 2 study evaluating the long-term safety, tolerability, and potential efficacy of orally-administered SAT-3247.
Methods: TRAILHEAD will enroll up to 30 male participants in Australia and the United States aged ≥16 years with a definitive diagnosis of DMD and a confirmed mutation in the DMD gene. Participants will receive SAT-3247 at a dose of 60 mg administered orally using a 5-days-on/2-days-off (weekday) dosing regimen for up to 12 months. This study will be conducted at multiple sites in Australia and the United States. The primary objectives include evaluation of long-term safety and tolerability of SAT-3247, as well as changes in fat fraction of the biceps brachii muscle measured by magnetic resonance imaging (MRI) following 12 months of treatment. Key secondary and exploratory objectives include quantitative assessments of muscle composition via MRI, muscle force by dynamometry, physical activity and function via limb sensors and PUL 2.0, pulmonary function, participant and caregiver quality of life, health economic impact, and proteomic biomarkers.
Results: Enrollment in TRAILHEAD is ongoing and demographic, clinical, imaging, and functional characteristics of participants enrolled in the study will be shared at the time of presentation.
Conclusions: The Phase 2 TRAILHEAD study will extend upon previously-reported results of SAT-3247 among adults living with DMD and will further elucidate the potential utility of a novel, recently-identified approach of AAK1 inhibition to increase muscle regeneration in people living with DMD.