Biogen Inc. announced the completion of the acquisition of RayThera Inc., a privately held biotechnology company focused on discovering and developing small-molecule therapies in immunology.

The acquisition strengthens Biogen’s growing immunology portfolio, adding multiple assets that have potential to treat immune-mediated conditions across a range of indications. The lead program entered Phase 1 development in July 2026.

“We are excited about the potential of these immunology assets as we continue to strengthen and diversify our pipeline for long-term growth,” said Priya Singhal, M.D., M.P.H., Executive Vice President and Head of Development at Biogen. “With the lead program now in Phase 1, this acquisition highlights strong execution on our open innovation model in sourcing external opportunities and reflects our continued investment in immunology as a strategic growth area.”