Biogen Inc. will present new data across its Alzheimer’s disease portfolio at the Alzheimer’s Association International Conference (AAIC) 2026, taking place July 12-15 in London, UK. The presentations will include data from the Phase 2 CELIA study evaluating diranersen, an investigational tau-targeting antisense oligonucleotide (ASO), and new analyses from studies of LEQEMBI (lecanemab). The company aims to underscore its leadership in Alzheimer’s care by highlighting advances in treatment delivery, real-world evidence, and approaches targeting core pathologies such as amyloid and tau.

Priya Singhal, M.D., M.P.H., Executive Vice President and Head of Development at Biogen, emphasized the significance of the data. "Tau has long remained one of the most important targets in Alzheimer’s disease, and the Phase 2 CELIA topline results for diranersen reinforce the potential of tau reduction as a therapeutic approach in early Alzheimer’s disease," Singhal said.

Diranersen and CELIA Study Data

The featured presentation on diranersen will include clinical, biomarker, and safety data from the CELIA study. This 18-month Phase 2 randomized, double-blind, placebo-controlled, dose-ranging study evaluated the efficacy, safety, and tolerability of diranersen in individuals with early Alzheimer’s disease. The study enrolled 416 participants with mild cognitive impairment due to Alzheimer’s disease or mild Alzheimer’s disease dementia, none of whom had previously received anti-amyloid therapy.

Diranersen is an investigational ASO designed to target microtubule-associated protein tau (MAPT) mRNA to reduce the production of tau protein. In 2025, the U.S. Food and Drug Administration (FDA) granted Fast Track designation to diranersen for the treatment of Alzheimer’s disease. Biogen obtained a worldwide, exclusive, royalty-bearing license to develop and commercialize diranersen from Ionis Pharmaceuticals in December 2019.

Lecanemab Presentations

Presentations on lecanemab will focus on subcutaneous administration and real-world use. Key sessions include emerging clinical evidence on the subcutaneous formulation and practical use considerations, such as at-home administration. Additionally, the LEADER study will provide three-year real-world evidence from diverse U.S. clinical settings, covering maintenance dosing and patient satisfaction.

LEQEMBI is a humanized monoclonal antibody directed against aggregated soluble protofibril and insoluble forms of amyloid beta. It is indicated in the U.S. for the treatment of Alzheimer’s disease in patients with mild cognitive impairment or mild dementia. The FDA granted traditional approval on July 6, 2023. Eisai serves as the lead of LEQEMBI development and regulatory submissions globally, with both companies co-commercializing the product.

Biogen Inc. has agreed to acquire RayThera Inc., a private biotechnology company, for up to $1 billion to expand its immunology pipeline. The transaction consists of an upfront payment and additional payments contingent on the achievement of future clinical and regulatory milestones. This acquisition will allow Biogen to add multiple anti-inflammatory assets to its portfolio, potentially treating immune-mediated conditions across various indications.

Transaction Details

Under the definitive agreement, Biogen will make an upfront payment to RayThera's shareholders. The total potential deal value of up to $1 billion includes these upfront funds and milestone payments. The transaction is subject to customary closing conditions, including the receipt of necessary regulatory approvals. It is currently anticipated to close in the third quarter of 2026.

Strategic Rationale

Priya Singhal, M.D., M.P.H., Executive Vice President and Head of Development at Biogen, stated that the acquisition deepens the company's pipeline in immunology. She emphasized that the new assets could allow Biogen to expand into new disease areas and contribute to its long-term pipeline potential. The lead candidate from RayThera's portfolio is expected to enter Phase 1 development in early Q3 2026.

Qing Dong, co-founder, Chairman and CEO of RayThera, expressed confidence in Biogen's global development capabilities in immunology. He highlighted the innovative pipeline built by the RayThera team and the rapid advancement of its molecules.

Post-Acquisition Plans

Once the transaction closes, Biogen will lead the development, manufacturing, and global commercialization of the acquired assets. RayThera is a small molecule drug discovery company focused on building an immunology pipeline. It recently completed its Series A financing co-led by Foresite Capital and OrbiMed Advisors, with participation from TTM Capital.