Biogen (BIIB) FY2025 results: revenue $9.9 billion, up 2.2% on the year

Biogen is a global biopharmaceutical company that discovers, develops and delivers therapies for serious and complex diseases, working mainly in neurology, specialised immunology and rare diseases. Its own marketed products are VUMERITY, TYSABRI, TECFIDERA, AVONEX and PLEGRIDY for multiple sclerosis; SPINRAZA for SMA; SKYCLARYS for FA; and QALSODY for ALS. The filing notes that the company introduced the first approved treatment for SMA, launched the first approved treatment targeting a genetic cause of ALS, and markets the first and only drug approved in the U.S., the E.U. and certain international markets for FA in adults and adolescents aged 16 years and older. Product sales of TYSABRI and of SPINRAZA each accounted for more than 10.0 percent of total revenue in 2025, 2024 and 2023. There were about 7,500 employees worldwide at the end of 2025, about 4,200 of them in the United States.

Multiple sclerosis and the neurology line

The filing describes a broad portfolio of medicines to treat MS, covering TECFIDERA, VUMERITY, AVONEX, PLEGRIDY and TYSABRI. The collaboration and licence agreement for global commercialisation rights to FAMPYRA was terminated with effect from 1 January 2025. In Alzheimer's disease the company works with Eisai on LEQEMBI and takes a 50.0 percent share of that product's revenue, net, and cost of sales, including royalties. In neuropsychiatry it works with Supernus on ZURZUVAE for PPD in adults following childbirth, which the filing says is among the most common complications during and after pregnancy.

Rare disease

Rare disease covers SPINRAZA for SMA, QALSODY for ALS, which became commercially available in the E.U. during the second quarter of 2024, and SKYCLARYS for FA, which became commercially available there during the first quarter of 2024. In November 2025 the company acquired Alcyone Therapeutics, a clinical-stage business built around ThecaFlex DRx, an implantable subcutaneous port and catheter device being investigated for intrathecal delivery of antisense oligonucleotides including SPINRAZA, as an alternative to repeated lumbar punctures. Consideration was about $85.0 million, a $50.0 million payment on closing plus $35.0 million paid on FDA approval of a supplemental application in January 2026, with up to a further $75.0 million in development and regulatory milestones.

The Genentech and Roche relationships

The company holds certain business and financial rights in a set of anti-CD20 therapies developed with Genentech, a wholly owned member of the Roche Group: RITUXAN and RITUXAN HYCELA for non-Hodgkin's lymphoma and chronic lymphocytic leukemia, GAZYVA for chronic lymphocytic leukemia, follicular lymphoma and, after approval in October 2025, lupus nephritis, OCREVUS for primary progressive and relapsing multiple sclerosis, LUNSUMIO for relapsed or refractory follicular lymphoma, and COLUMVI, a bispecific antibody for non-Hodgkin's lymphoma. There is also an option to add other potential anti-CD20 therapies. All of these products are marketed and distributed by the Roche Group and its sublicensees, not by Biogen.

Biosimilars

The company commercialises biosimilars of advanced biologics under its agreement with Samsung Bioepis in certain international markets: BENEPALI, an etanercept biosimilar referencing ENBREL; IMRALDI, an adalimumab biosimilar referencing HUMIRA; and FLIXABI, an infliximab biosimilar referencing REMICADE. It distributes these in certain European countries and holds an option to acquire exclusive distribution rights in China. During 2025 it completed the sale of its rights to two others, TOFIDENCE and BYOOVIZ.

Selling and making

Marketed products are promoted worldwide, including in the United States, Europe, Asia, the Middle East and Latin America, primarily through the company's own sales forces and marketing groups, with third-party partners used in some countries as it expands into new geographies. Selling effort goes to health care providers in private practice or at major medical centres, through sales representatives calling in person and virtually, advertisements, professional symposia, direct mail, digital and point of care marketing and public relations. In the United States the products are distributed principally through wholesale and specialty distributors and specialty pharmacies, while outside it the arrangement varies by country, in some cases through third-party distribution partners who take on most of the marketing and distribution. Manufacturing runs from Research Triangle Park in North Carolina, which makes AVONEX and PLEGRIDY and also holds a drug product facility with a parenteral plant and an oral solid dose plant, and from a large-scale biologics facility in Solothurn, Switzerland, which is operational and approved for LEQEMBI and TYSABRI. The company also uses strategic contract manufacturing partners.

From Biogen's annual report on Form 10-K for the year ended 31 December 2025. The filing

Written from the 10-K filed 6 February 2026: read the full 10-K.