GlaxoSmithKline PLC has issued a tender offer for all of the outstanding shares of Tesaro Inc. for $75 apiece as the U.K.'s biggest pharmaceuticals company acquires the Waltham, Mass.-based biotechnology company.
GSK on Dec. 3 announced plans to buy the U.S.-based cancer drug developer for $5.1 billion. Tesaro's main product is Zejula, which is approved in the U.S. and Europe for ovarian cancer.
Tesaro has yet to file a statement with a recommendation of its directors for stockholders to submit their shares in the offer, which began Dec. 14 and will end Jan. 14, 2019.
Following the completion of the offer, GSK unit Adriatic Acquisition will acquire all remaining shares through a merger. The transaction, which includes the offer and merger, is subject to the approval of Tesaro's stockholders and other closing conditions.
According to GlaxoSmithKline, stockholders owning 25.7% of all issued and outstanding shares of Tesaro have already agreed to submit their shares in the offer as of Dec. 10.