Biogen (BIIB) Stock Analysis & Winston Score

Biogen is a biotechnology company that makes medicines for serious brain and nervous system diseases. Its main products treat multiple sclerosis (MS), spinal muscular atrophy (SMA), and Alzheimer's disease. The company sells drugs like Tecfidera, Spinraza, and Leqembi, primarily to hospitals, neurologists, and specialty pharmacies in the United States and Europe. Biogen makes money by selling prescription drugs, earning revenue each time a patient fills a prescription or a hospital orders treatment. It operates globally, with the US generating the majority of sales, and reported roughly $9–10 billion in annual revenue in recent years. Its moat comes from patented medicines and deep expertise in neurology, a field most drug companies avoid due to its complexity. The biggest growth opportunity is Leqembi, its Alzheimer's drug developed with Eisai, but slow patient uptake and questions about real-world effectiveness remain key risks to watch.