Reldesemtiv

Fast skeletal muscle troponin activator

Reldesemtiv is an investigational, small molecule fast skeletal muscle troponin activator, or FSTA. Reldesemtiv slows the rate of calcium release from the regulatory troponin complex of fast skeletal muscle fibers. Contraction of skeletal muscles is driven by the sarcomere, the fundamental unit of muscle contraction, which contains myosin, a protein which converts chemical energy into mechanical force through its interaction with another protein, actin. This interaction is regulated by other proteins including troponin and tropomyosin, and is dependent on changes in calcium. By slowing the rate of calcium release, reldesemtiv sensitizes the sarcomere to calcium, leading to an increase in muscle contractility

Reldesemtiv was the subject of COURAGE-ALS (Clinical Outcomes Using Reldesemtiv on ALSFRS-R in a Global Evaluation in ALS), a Phase 3, multi-center, double-blind, randomized, placebo-controlled trial in patients with ALS. In March 2023, COURAGE-ALS was discontinued due to futility at the second planned interim analysis.