The U.S. Food and Drug Administration issued a complete response letter rejecting Biohaven’s new drug application for troriluzole to treat spinocerebellar ataxia, prompting immediate corporate restructuring. Biohaven said the FDA cited problems with the externally‑controlled, real‑world evidence dataset used to support efficacy. The company announced plans to reduce annual R&D spending by roughly 60% and to reprioritize its pipeline toward three late‑stage programs. Real‑world evidence (RWE) refers to clinical data collected outside randomized controlled trials, often from registries or electronic health records; regulators have warned that externally controlled trials can suffer from bias unless effects are large and pre‑specified.