(Bloomberg) -- AstraZeneca Plc and Pfizer Inc. are among firms considering a counteroffer for Medivation Inc., challenging Sanofi’s $9.3 billion bid for the company, people familiar with the matter said.

Novartis AG is also exploring a bid, said people familiar with the matter. The Basel, Switzerland-based firm, along with Pfizer and AstraZeneca, are talking to advisers about Medivation’s value and next steps, including possible bids, the people said. The deliberations are at an early stage and the companies may decide against making offers, they said.

Medivation is looking for bids of at least $65 a share, a separate person said. Medivation rejected Sanofi’s $52.50 per share offer Friday, and said it substantially undervalued the company. Sanofi has the capacity to increase its offer for the San Francisco-based business, though it is reluctant to overpay, two of the people said.

Representatives for AstraZeneca, Pfizer, Medivation and Novartis declined to comment. A Sanofi spokesman said the company looks forward to taking its proposal to Medivation shareholders and declined to comment further.

Medivation specializes in therapies for hard-to-treat diseases. The need for new treatments to spur growth is pushing spending on acquisitions for pharmaceutical, health-care and biotechnology companies up 27 percent from last year, when the industry was on its way to setting a more than 12-year record. Sanofi took its offer public on Thursday after Medivation didn’t respond to an earlier approach and hired banks to defend itself.

Medivation Chief Executive Officer David Hung declined to meet with his Sanofi counterpart and said the company’s board had no interest in discussing the transaction, according to a letter by Sanofi CEO Olivier Brandicourt that the French drugmaker made public Thursday. Brandicourt put the all-cash proposal in a letter to Hung dated April 15. Medivation only acknowledged its receipt.

Medivation has one marketed medicine for prostate cancer called Xtandi. The company is also developing pidilizumab, another immuno-oncology drug, to be used as a treatment for blood cancers and is working on talazoparib for the treatment of breast cancer.

--With assistance from Ketaki Gokhale and Cynthia Koons To contact the reporters on this story: Manuel Baigorri in London at, Ruth David in London at, Dinesh Nair in London at To contact the editors responsible for this story: Aaron Kirchfeld at, Chitra Somayaji at, Amy Thomson, Marthe Fourcade

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