Biogen acquires RayThera in deal worth up to $1 billion

Biogen acquires RayThera in deal worth up to $1 billion Quartz · Bloomberg / Getty Images Colleen Cabili Thu, June 18, 2026 at 3:40 PM GMT+2 2 min read BIIB Biogen agreed to acquire RayThera Inc. , a private San Diego-based biotechnology company developing small-molecule anti-inflammatory therapies, for up to $1 billion, the companies said Wednesday. Shareholders of RayThera will receive an upfront payment, with the total deal value subject to increase through payments tied to hitting future clinical and regulatory benchmarks, the company said.

Closing is anticipated in the third quarter of 2026, pending customary regulatory approvals and other standard conditions. After closing, responsibility for bringing RayThera's assets through development, manufacturing, and global commercialization will transfer to Biogen. Among the assets changing hands are several small-molecule drug candidates aimed at immune-mediated conditions spanning various therapeutic indications.

The company said its most advanced program is on track to begin Phase 1 testing no later than early in the third quarter of this year. "With this acquisition, we are further deepening our pipeline in immunology by adding a suite of assets that can allow us to expand into new disease areas," Priya Singhal, Executive Vice President and Head of Development at Biogen, said in a statement. "We believe these assets can meaningfully contribute to our long-term pipeline potential and we're excited about the opportunity to rapidly advance the first candidate into the clinic.

" Qing Dong, co-founder, Chairman, and CEO of RayThera, said in a statement that Biogen's "strong global development capabilities in immunology" make it "the natural fit" to advance the programs into Phase 1 and beyond. RayThera was co-founded by Qing Dong and Gene Hung, M. D.

, and completed a Series A financing round co-led by Foresite Capital and OrbiMed Advisors, with participation from TTM Capital, according to Pharmaphorum . The two co-founders previously built and sold two other San Diego biotech companies — FronThera and XinThera — to Alumis and Gilead Sciences, respectively, according to Pharmaphorum . The RayThera deal comes shortly after Biogen completed its acquisition of Apellis Pharmaceuticals , a transaction that added two complement-targeting drugs — SYFOVRE and EMPAVELI — to its portfolio in a deal valued at about $5.

3 billion. That acquisition expanded Biogen's presence in nephrology and ophthalmology. Pressure on Biogen's revenue base — driven in part by biosimilar rivals eroding sales of the MS drug Tysabri and other core products — has intensified the company's push to diversify its pipeline through acquisitions.