Regeneron Pharmaceuticals is a biotechnology company built on Eylea, a treatment for age-related macular degeneration and other eye diseases that has been one of the best-selling drugs in ophthalmology for years, alongside Dupixent, an immunology drug developed in partnership with Sanofi that treats conditions like eczema and asthma. The company runs its own antibody discovery technology platform, which it uses both to develop its own drugs and to partner with other pharmaceutical companies on shared discovery programs. As Eylea faces biosimilar competition, the pharmaceutical equivalent of generic drugs, Regeneron has worked to transition patients to a higher-dose reformulation and to grow Dupixent and its pipeline of newer drugs to offset that pressure. The company has also moved into obesity and cardiometabolic treatments, entering the same fast-growing therapeutic category that has reshaped growth expectations for Eli Lilly and Novo Nordisk.