Pfizer will pay Medivation shareholders $81.50 per share in cash, a 21 percent premium to Medivation's closing stock price Friday of $67.16.
Ian Read, chairman and CEO of Pfizer, said in a joint press release the proposed deal is expected to "immediately accelerate revenue growth and drive overall earnings growth potential for Pfizer."
"The addition of Medivation will strengthen Pfizer's Innovative Health business and accelerate its pathway to a leadership position in oncology, one of our key focus areas," he said, "which we believe will drive greater growth and scale of that business over the long-term. This transaction is another example of how we are effectively deploying our capital to generate attractive returns and create shareholder value."
Pfizer will get access to Medivation's prostate cancer drug Xtandi, which the companies said treated 64,000 men to date in the U.S. alone and generated about $2.2 billion in worldwide net sales over the past four quarters.
Medivation has two development-stage drugs: breast cancer drug talazoparib and lymphoma drug pidilizumab. This will also add to Pfizer's oncology portfolio. Cancer remains the second leading cause of death in the U.S., according to the Center for Disease Control and Prevention.
Pfizer said the acquisition would also add about 5 cents to earnings in the first full year after close and doesn't expect the deal to impact its 2016 forecast.
Both company's boards have unanimously approved the merger.
Pfizer said it expects to complete the acquisition in the third or fourth quarter.
Medivation's stock has risen significantly this year, up more than 66 percent.
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Shares of Pfizer dropped to nearly 1 percent Monday in premarket trading. The company's stock has gone up this year, up more than 8 percent.
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