Founded in 1978, Biogen focuses on neuroscience and biotechnology research. The company's core portfolio includes multiple sclerosis therapies such as Tecfidera, Tysabri, and Avonex, as well as Spinraza for spinal muscular atrophy. Biogen has expanded its focus into rare diseases and Alzheimer's disease, notably co-commercializing the anti-amyloid therapy Leqembi with Eisai. In addition to its branded therapeutics, the company generates revenue through biosimilars and strategic collaboration agreements, including anti-CD20 therapeutic programs with Genentech. Biogen operates globally, serving specialist healthcare providers and patient populations with complex medical needs.