Pfizer and King Pharmaceuticals, Inc. have entered into a definitive merger agreement under which Pfizer will acquire King for $3.6 billion in cash. The transaction, subject to customary closing conditions, is expected to close in late 4Q10 or 1Q11.

The acquisition provides an immediate revenue boost from King’s portfolio, which includes a prescription pharmaceutical business focused on new formulations of pain treatments designed to discourage misuse and abuse, as well as the Meridian auto-injector business for emergency drug delivery, which manufactures the EpiPen, and an animal health business that offers a variety of feed additive products for a wide range of species. King’s three key businesses will be aligned with Pfizer’s Primary Care, Established Products and Animal Health business units. The Meridian unit has a long-standing critical supply relationship with the U.S. Department of Defense.

“We are highly impressed by King’s innovative products and technology in the pain relief disease area, as well as by its success in advancing promising compounds in its pipeline. The combination of our respective portfolios in this area of unmet medical need is highly complementary and will allow us to offer a fuller spectrum of treatments for patients across the globe who are in need of pain relief and management,” stated Jeffrey Kindler, Pfizer’s chairman and chief executive officer.”In addition, the revenue generated by King’s portfolio will further diversify Pfizer’s business, while at the same time contributing to steady earnings growth and shareholder value.”