Biogen agreed to acquire RayThera in a deal valued at up to $1 billion, adding a suite of early-stage immunology-focused small-molecule candidates to its pipeline. RayThera’s investors will receive an undisclosed upfront payment plus potential milestone payments tied to clinical and regulatory progress. The acquisition follows Biogen’s expanding immunology strategy, including its earlier $5.6 billion purchase of Apellis for complement-targeting assets. RayThera, founded in 2023, disclosed limited pipeline detail publicly, describing prospects as “anti-inflammatory” while patents suggest targets across pathways such as TNF activity modulation and STAT6 and JAK2. Biogen said it aims to deepen pipeline diversification beyond its core neurology base, with the lead RayThera candidate positioned to enter Phase I in early Q3 2026. The transaction is expected to close in Q3 2026.