Biogen struck a deal to acquire RayThera in a transaction valued at up to $1 billion, aiming to deepen its immunology pipeline with anti-inflammatory small-molecule candidates. The acquisition, announced after RayThera’s $110 million Series A, includes undisclosed upfront terms and milestone-driven upside tied to clinical and regulatory progress. Biogen said the move expands its immunology portfolio beyond neurology and brings multiple assets into its early pipeline. RayThera’s lead program is expected to enter Phase I clinical development in early Q3 2026, giving Biogen a near-term pathway to generate human data. The company’s cash flow and pipeline strategy align with recent immunology M&A: Biogen also acquired Apellis for $5.6 billion earlier this year, adding marketed complement therapeutics and earlier-stage research projects. RayThera’s acquisition further diversifies the types of immune targets Biogen can pursue. For RayThera, founded by Qing Dong and Gene Hung, the transaction represents a rapid value realization after raising institutional capital and building a focused immunology discovery platform that has disclosed limited public detail on specific targets.