Pfizer has won the race for biotech firm Medivation. The US drugs giant has agreed to pay about $14 billion in a move that adds leading prostate cancer drug Xtandi to its portfolio. Xtandi already generates just over $2 billion in annual sales with potential to more than double, according to analysts. The deal ends months of bidding for the San Francisco-based firm which rejected offers from rival Sanofi with US Merck, Celgene and Gilead Sciences also reported to have shown interest.

Pfizer will pay $81.50 per share, which represented a 21% premium to Medivation’s closing stock price on Aug. 19. It plans to finance the transaction from its existing cash holdings. Both boards have unanimously approved the merger which is expected to close in the third or fourth quarter of 2016, subject to customary conditions and regulatory approval. Medivation could pay Pfizer a $510 million termination fee if the deal does not complete.

Ian Read, Pfizer’s chairman and CEO, said the addition of Medivation would strengthen its innovative health business and accelerate its path to a leadership position in oncology. Pfizer’s Ibrance breast cancer treatment is also a market leader and had sales of $723 million in 2015. Medivation has a promising pipeline of late-stage oncology assets, namely breast cancer treatment Talazoparib and immuno-oncology drug Pidilzumab which is being developed for diffuse large B-cell lymphoma and other hematologic cancers.

Frank D’Amelio, Pfizer’s chief financial officer, said the purchase of Medivation would not impact the timing of any decision to break up the company. Read stated earlier this month that Pfizer would decide by the end of the year whether it would split into two, following suggestions at its second-quarter financial results conference that it was having second thoughts.