Sanofi launches $9.3 bln fight for U.S. cancer firm Medivation

* Sanofi (LSE: 0O59.L - news) makes approach public after Medivation (NasdaqGS: MDVN - news) stonewalls

* Deal at $52.50 a share would boost Sanofi EPS immediately

* Analysts see scope for sweetened offer (Updates to include historical premiums)

By Ben Hirschler and Leigh Thomas

LONDON/PARIS, April 28 (Reuters) - French drugmaker Sanofi went public with a $9.3 billion offer to buy Medivation on Thursday, setting up what could be a lengthy takeover battle after the U.S (Other OTC: UBGXF - news) . cancer firm rebuffed its approaches.

The decision to target Medivation marks a return to the biotech takeover trail for Sanofi, which is looking to new cancer treatments to bolster its portfolio and help offset declining sales of mainstay diabetes drug Lantus.

Sanofi's non-binding proposal is to buy Medivation for $52.50 per share in cash, representing a roughly 36 percent premium over Medivation's stock price one month prior to Thursday's offer.

It (Other OTC: ITGL - news) is, however, only modestly above Medivation's Wednesday closing price of $52.05 and investors signalled they expected Sanofi to dig deeper, with the shares trading above $56 on Thursday.

In 2015, the average offer price among life sciences deals was 40 percent above the target's stock price four weeks earlier, according to data from Thomson Reuters (Dusseldorf: TOC.DU - news) . Biotech deals saw even frothier premiums, typically around 50 percent.

Reuters reported last month that Medivation had been working with investment bank J.P. Morgan (Other OTC: MGHL - news) to handle interest from companies regarding a potential acquisition, but it had no plans to sell itself.

Bryan Garnier analyst Eric Le Berrigaud said Sanofi could now face a prolonged takeover fight with other players potentially getting involved, including Japan's Astellas Pharma (Other OTC: ALPMF - news) , Medivation's partner on its prostate cancer drug Xtandi.

Britain's AstraZeneca (NYSE: AZN - news) has also been reported to have looked at Medivation.

Officials at Astellas and AstraZeneca declined to comment, although one person close to the British company said it was unlikely to enter a bidding war.

Medivation, which has limited takeover defences, said it would respond to Sanofi's offer following a board meeting on Thursday, with input from financial advisers Evercore and J.P. Morgan.

Sanofi, which is being advised by Morgan Stanley (Xetra: 885836 - news) , has a track record of pushing through unsolicited deals, after buying Genzyme for $20 billion in 2011.

Sanofi's move comes on the same day that Abbott Laboratories (Xetra: 850103 - news) agreed to buy medical device maker St. Jude Medical for $25 billion and AbbVie (LSE: 0QCV.L - news) announced a $5.8 billion deal for cancer firm Stemcentrx, highlighting a pattern of healthcare companies snapping up smaller rivals.

LOOKING FOR DEALS

The French company, whose shares slipped 1 percent, said there was no certainty the deal would get done, but that if it did, it would boost earnings immediately.

Deutsche Bank (LSE: 0H7D.L - news) analysts said Sanofi likely had "significant flexibility" to raise its offer, given the current low cost of debt, while Bernstein calculated the deal would still lift earnings from 2017 even at $62.40 a share, or 20 percent above Wednesday's close.

The premium to the unaffected price offered by Sanofi is below some other recent large biotech deals, with Roche paying a 63 percent premium for Intermune in 2014 and Alexion 140 percent for Synageva last year.

Stepping up acquisitions fits with the strategy of Sanofi Chief Executive Olivier Brandicourt, who took over a year ago. He told Reuters in January that he was looking for deals to broaden its reach in areas such as oncology and could consider deals of up to $20 billion.

France's biggest drugmaker is going through a tough patch, due to falling sales of Lantus, prompting it to warn of no meaningful profit growth over the next two years.

Oncology is currently the hottest area of pharmaceutical research, thanks to advances in understanding the biological drivers of the disease. Sanofi has a long history in selling chemotherapy drugs but has been less successful at developing modern cancer medicines.

'COMPELLING' PROPOSAL

Brandicourt first contacted Medivation about a deal on March 25 but he said Chief Executive Officer David Hung had declined to meet him and had told him the U.S. company's board was not interested in discussing a transaction.

Sanofi then set out its $52.50-a-share offer in an April 15 letter to Hung, to which Medivation only acknowledged receipt without commenting on its contents.

"We do not understand the delay in responding to our letter. The price we put forth represents a very substantial premium, and it would be all cash without any financing condition. In these circumstances we believe it is appropriate to make this letter public, which we are doing today," Brandicourt wrote in a follow-up letter to Hung on April 28.

"We also strongly believe that Medivation shareholders would find our proposal to be compelling."

Xtandi, which had worldwide sales of nearly $2 billion in 2015, is Medivation's only marketed drug. The high price of Xtandi has been criticised by some U.S. lawmakers, including Democratic Party presidential hopeful Bernie Sanders.

Medivation is also conducting clinical trials on two experimental drugs, talazoparib for breast cancer and pidilizumab for blood cancers.

(Editing by Keith Weir and Cynthia Osterman)