Irish biopharmaceutical firm Horizon Pharma has completed the acquisition of US-based Hyperion Therapeutics for around $1.1bn.
The deal was first announced at the end of March.
Horizon noted that acquisition of Hyperion has been completed following successful tender for 86% of its outstanding shares.
Under the deal, Horizon purchased all the issued and outstanding shares of Hyperion’s common stock for $46.00 per share in cash.
Horizon Pharma president and CEO Timothy Walbert said: "This is a transformational transaction for Horizon Pharma and adds two important medicines, Ravicti and Buphenyl, which will help strengthen our orphan business and set the foundation for continued growth.
"Above all else, Horizon Pharma is a ‘patients first’ company, so our goal through the integration of these medicines into our portfolio is to ensure continued access for the patients receiving treatment and the physicians who treat them."

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By GlobalDataRavicti and Buphenyl medicines have been developed to treat people with urea cycle disorders (UCDs), a combination of inherited metabolic problems.
Horizon noted that marketing authorisation application was filed for European marketing of Ravicti. Being marketed in the US, Ravicti (glycerol phenylbutyrate) oral liquid received approval in the US in February 2013.
Horizon produces products for arthritis, inflammation and orphan diseases, including Actimmune (interferon gamma-1b), Duexis (ibuprofen/famotidine), Pennsiad (diclofenac sodium topical solution) 2% w/w, Rayos (prednisone) delayed-release tablets and Vimovo (naproxen/esomeprazole magnesium).