Horizon Pharma plc to Acquire Hyperion Therapeutics, Inc. for $46.00 per Share or $1.1 Billion in Cash

Addition of RAVICTI(R) (Glycerol Phenylbutyrate) Oral Liquid and BUPHENYL(R) (Sodium Phenylbutyrate) Tablets and Powder Significantly Expands Horizon’s Orphan Business; Transaction Is Expected to Be Immediately Accretive to Adjusted Earnings Per Share and Contribute Approximately $100 Million in Adjusted EBITDA in 2016