Biogen Inc. (BIIB) Stock Rating & Analysis

Biogen is a biopharmaceutical company focused on treatments for neurodegenerative and rare diseases. Its declining multiple sclerosis franchise is its biggest revenue source at 40% of total revenue in 2025. It also earns significant revenue (19% of total in 2025) from CD20 collaboration agreements with Roche covering the oncology drugs Rituxan and Gazyva and the multiple sclerosis drug Ocrevus.