Understand any stock in simple English
Enter a ticker to learn what the company does and how it makes money.
Biogen makes and sells medicines for brain and nerve diseases.
Biogen is a biotechnology company that discovers, develops, and sells prescription medicines, mostly for diseases of the brain and nervous system. Its customers are not regular shoppers — they are hospitals, clinics, pharmacies, and insurers, and ultimately patients, who get these drugs through doctors. The company makes money by selling its approved medicines, and it also earns a share of profits from drugs it partners on with other companies. Its headquarters are in Cambridge, Massachusetts, which puts it in the middle of one of the world's densest clusters of biotech research and talent.
Think of Biogen as a specialist doctor for the nervous system rather than a general pharmacy. Its biggest sellers have historically been treatments for multiple sclerosis, a disease where the body's immune system attacks the nerves. It also sells a drug for spinal muscular atrophy, a rare and devastating genetic condition in babies and young children, and it has pushed into Alzheimer's disease with a medicine designed to clear a protein called amyloid from the brain. The Alzheimer's drugs have been the most talked-about part of the story: they won regulatory approval, but their rollout has been slow and controversial because of questions about how much they actually help patients and how they are paid for. Biogen has also been cutting costs and reshaping its pipeline as some older drugs face cheaper competition, and it has looked to partnerships and acquisitions to refill its shelves with new products, including deals in areas like depression and rare diseases.
The business is a classic high-risk, high-reward research engine: decades and billions of dollars can go into a drug that never works, but a single success can be enormously profitable. Biogen uses its cash to fund that research, buy promising science from other companies, and return some money to shareholders. It has also faced pressure from generic competition on older products and from investors wanting faster growth. The core question for Biogen is simple: can it keep finding and selling medicines that genuinely change the lives of people with brain and nerve diseases, and get paid well enough for them to fund the next round of discovery?
Saved answer · last researched 15 Oct 2026