Horizon Pharma buying Hyperion for about $1.1 billion

Irish firm Horizon Pharma is buying Hyperion Therapeutics for about $1.1 billion, gaining two treatments for genetic disorders.

Dublin-based Horizon Pharma said Monday that it would pay $46 a share for the Brisbane, Calif., company, marking a 5.6% premium to Hyperion’s closing stock price Friday, before the deal was announced.

The move adds the drugs Raviciti and Buphenyl to Horizon’s offerings. Both drugs are aimed at treating inherited disorders called urea cycle disorders that affect about 2,100 people in the U.S. The genetic condition affects how the body removes nitrogen from the blood. Nitrogen buildup can be toxic.

Combined, the drugs had sales of $113.6 million in 2014.

Horizon has five products, including Actimmune, which is focused on treating the genetic condition chronic granulomatous disease, encompassing a group of immune system conditions. That had sales of $25.3 million in 2014.

The biotechnology company’s biggest revenue comes from the rheumatoid arthritis and osteoarthritis treatment Vimovo, at $163 million in 2014. Overall, Horizon had $297 million in net sales in 2014.

The companies expect the deal to close during the second quarter.

Shares of shares of Hyperion rose $3.24, or 7.6%, to $45.98, while Horizon Pharma shares gained $3.97, or 18.2%, to $25.78.