Merck to Buy Idenix for $3.85 Billion -- Update

By Erin McCarthy 

Merck & Co. agreed to buy Idenix Pharmaceuticals Inc. in a bid to expand its portfolio of hepatitis C treatments.

The pharmaceutical company said it will acquire Idenix for $24.50 per share in cash, more than three times Idenix's closing price Friday.

Idenix is a biopharmaceutical company that focuses on developing treatments for human viral diseases, including hepatitis C. The company currently has three hepatitis C drug candidates in clinical development, the companies said. It has no products on the market.

"Idenix's investigational hepatitis C candidates complement our promising therapies in development" and will help to develop a highly effective, once-daily, all-oral treatment, said Dr. Roger Perlmutter, president of Merck Research Laboratories.

Merck has several hepatitis C medicines in development, including one that has received breakthrough therapy designation from the U.S. Food and Drug Administration, the company said.

Spending on specialty drugs, including treatments for hepatitis C, are expected to surge in the next two years, according to an April report from Express Scripts. It had forecast the U.S. will spend 1,800% more on hepatitis C medications in 2016 than it did in 2013.

The deal, which has been approved by both companies' boards, is expected to close in the third quarter.

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