PI-111

PI-111 is a first-in-class, patented topical small molecule muscle relaxant being developed by Prima Innovations. It acts as an antispasmodic by specifically targeting the NaV 1.4 sodium channel (SCN4A) located in skeletal muscles. Unlike traditional oral muscle relaxants that often act on central nervous system (CNS) targets, PI-111 is designed for topical application to provide localized relief of acute musculoskeletal pain and chronic muscle spasms—including those in the back, neck, shoulder, and legs—while avoiding systemic side effects such as drowsiness and cognitive impairment. The program has established proof-of-principle in four animal models and is currently in preclinical development.