Merck to Buy Idenix Pharma for $3.85 Billion

Merck will spend nearly $4 billion for Idenix Pharmaceuticals with a per-share bid worth more than triple the per-share price of the hepatitis C drug developer.

Merck & Co says the Cambridge, Massachusetts, company has built a promising portfolio of hepatitis C treatments, including three in clinical testing

Merck will spend $24.50 per share in cash for each share, which closed at $7.23 Friday. Shares of Idenix Pharmaceuticals Inc soared almost 240 percent in premarket trading Monday. The boards of both companies have approved the deal.

Drugmakers are racing to develop new, potentially lucrative treatments for the blood-borne disease, which causes liver damage. The pill Sovaldi racked up more than $2 billion in sales for Gilead Sciences in its first full quarter. Merck is based in Whitehouse Station, New Jersey.