Setara Biosciences launched with $90 million in Series A funding, building on a portfolio carried forward after Jazz Pharmaceuticals acquired Actio Biosciences. The new company is pursuing rare-disease genetics at scale, with its lead program STAR-0871 advancing a genetics-root approach to both a rare neuromuscular disorder and a more prevalent condition. STAR-0871 is a small-molecule TRPV4 inhibitor originally developed at Actio as ABS-0871. Setara plans to develop it for Charcot-Marie-Tooth disease type 2C, a rare inherited neuromuscular disorder affecting about 2,500 people in the US tied to gain-of-function TRPV4 gene mutations. The company’s strategy is to selectively block overactive TRPV4 signaling that drives the disorder’s biology. Setara’s platform ambition extends beyond rare disease: TRPV4 is also implicated in bladder and neuromuscular signaling, and management described a “one to many” approach toward the overactive bladder market. Jazz’s acquisition of Actio in August left behind an asset set that Setara now intends to carry forward under new ownership. Setara cofounder David Goldstein said Series A funding was built largely on Actio’s investor syndicate, with Jazz joining as a new shareholder.