Biogen agreed on 17 June to acquire RayThera, a privately held San Diego biotech developing small-molecule therapies for immune-mediated diseases, for up to $1bn.
Why Biogen Inc. is buying RayThera Inc.
Biogen said RayThera's anti-inflammatory assets could treat immune-mediated conditions across a range of indications and allow it to expand into new disease areas. Biogen takes over global development, manufacturing and commercialisation.
“Biogen is the natural fit to move these assets forward into Phase 1 development and beyond”
Deal terms and financing
RayThera shareholders receive an upfront payment, which was not disclosed, and are eligible for clinical and regulatory milestones that make up most of the potential value.
Regulatory approvals and timing
Closing was expected in the third quarter subject to regulatory approvals. Biogen announced on 6 August 2026 that it had completed the deal.
Market context
RayThera was co-founded by Qing Dong and Gene Hung. Its Series A was co-led by Foresite Capital and OrbiMed Advisors with participation from TTM Capital.
