Horizon Pharma plc is a biopharmaceutical company focused on developing medicines for the treatment of orphan diseases, arthritis, pain, and inflammation and inflammatory diseases. The company markets 11 medicines through its orphan, rheumatology and primary care business units, including ACTIMMUNE, BUPHENYL, DUEXIS, RAVICTI, QUINSAIR and PENNSAID. Horizon Pharma Public Limited Company was founded in 2005 and is headquartered in Dublin, Ireland.