Blockbuster breakup: Amylin buys out Lilly's exenatide rights in $1.6B deal

The decade-long union of Amylin ($AMLN) and Eli Lilly ($LLY) on the diabetes front ended in a blockbuster breakup today, with Amylin agreeing to pay Lilly $250 million upfront and up to $1.2 billion from the sales of exenatide products in exchange for full rights to the drug and its successors.

The divorce was presented today as an amicable ending to a long and fruitful partnership, but Amylin has been acting anything but amicably over the course of the year. The biotech filed suit against Eli Lilly earlier this year after the pharma giant joined forces with Boehringer Ingelheim, a rival in the diabetes field, on Trajenta. Today's agreement also ends the litigation.

Under the terms of the deal, Amylin will hand over a $1.2 billion secured note to Lilly, paying it off with the sales revenue from exenatide products. But if the FDA still hasn't approved the once-weekly injectable Bydureon--the successor to Byetta--by mid-2014, then the revenue sharing deal will terminate and Lilly's share of the sales revenue will shrink from 15% to 8%. FDA approval of a once-monthly version of the drug, now in mid-stage development, would trigger a $150 million milestone payment. Transitioning worldwide commercialization and development of new exenatide products starts in the U.S. at the end of this month then rolls around the globe by the end of 2013.

"Lilly remains confident that the resubmission package for Bydureon has addressed the requirements outlined by the FDA and looks forward to Amylin achieving the alliance's long-held goal of making Bydureon available to patients in the U.S.," said Enrique Conterno, president of Lilly Diabetes. "Looking forward, Lilly Diabetes remains committed to providing a comprehensive portfolio of diabetes treatment options for patients through our currently marketed products and robust clinical pipeline."

Alkermes, which has a royalty stake in the success of Bydureon, will evidently stay with Amylin now that the two big partners have severed their union.

- check out the press release

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