Biogen Inc. (Biogen (BIIB)) is making another move to diversify beyond its Alzheimer's focus. On Wednesday, the company announced it will acquire private biotech RayThera Inc. in a deal worth up to $1 billion.
The acquisition is designed to expand Biogen's immunology pipeline, adding early-stage assets that target inflammatory and immune-mediated diseases. The upfront payment to RayThera shareholders is relatively small; the bulk of the consideration is tied to hitting clinical and regulatory milestones down the road.
The transaction is expected to close in the third quarter of 2026.
What Biogen Is Getting
RayThera is a small-molecule therapy developer focused on immunological diseases. Its portfolio includes several anti-inflammatory programs that could treat a range of immune-mediated conditions. The lead candidate is slated to enter Phase 1 development in early Q3 2026 — so it's still very early stage.
Biogen has been synonymous with Alzheimer's disease for years, but the company has been actively reshaping its pipeline through M&A. In May, Biogen reported Phase 2 results for diranersen (BIIB080), an experimental tau-targeting therapy for early Alzheimer's. The data showed cognitive benefits and reductions in tau biomarkers, even though the study missed its primary endpoint.
But Biogen isn't putting all its eggs in the Alzheimer's basket. The RayThera deal is the latest in a string of moves to bolster its immunology and rare disease portfolio. In March, Biogen acquired Apellis Pharmaceuticals for $41 per share in cash — about $5.6 billion — to strengthen its position in immunology and rare diseases. In April, Biogen struck a deal with Alloy Therapeutics to accelerate development of antisense therapies for multiple undisclosed indications. Alloy received an undisclosed upfront payment and is eligible for milestone payments and tiered royalties.
Biogen shares were down 2.38% at $193.93 on Thursday afternoon.
