Angelini Pharma agreed to acquire Catalyst Pharmaceuticals for about $4.1 billion in cash, adding a portfolio of three FDA-approved rare-disease CNS medicines and a larger US commercial footprint. The deal values Catalyst at $31.50 per share, a premium of about 21% to the prior close, and is expected to close in the third quarter of 2026. Catalyst’s marketed assets include Firdapse (amifampridine) for Lambert-Eaton myasthenic syndrome, Agamree (vamorolone) for Duchenne muscular dystrophy, and Fycompa (perampanel) for certain seizure types. In 2025, Catalyst reported roughly $589 million in revenue, driven primarily by these franchises. Angelini positioned the acquisition as a platform build for “brain health” and rare neurological diseases, with an integration plan focused on Catalyst’s commercial infrastructure. The company also cited its ongoing epilepsy development in multiple clinical trials. The transaction follows a broader slate of neuroscience-focused dealmaking and underscores how established revenue-generating rare-disease products continue to attract strategic buyers as they seek scale in the US market.