Horizon Therapeutics plc is an Irish-domiciled biopharmaceutical company focused on the discovery, development, and commercialization of medicines addressing critical needs in rare, autoimmune, and severe inflammatory diseases.
Founded in 2005 and headquartered in Dublin, Ireland, with operational headquarters in Lake Forest, Illinois, the company developed therapies such as Tepezza (teprotumumab) for thyroid eye disease, Krystexxa (pegloticase) for refractory gout, and treatments for conditions like cystinosis and urea cycle disorders. Its portfolio also included products for rheumatology and inflammation, including Duexis, Pennsaid, and Rayos.
Acquired by Amgen Inc. in October 2023 for approximately $27.8 billion, Horizon operates as a subsidiary, contributing to Amgen's rare disease portfolio with around 2,190 employees and 2022 revenues of $3.6 billion prior to the acquisition.
