In December 2012, Christopher Cox, cochair of the corporate group at Cadwalader, Wickersham & Taft, was retained by Irish drugmaker Élan Corporation PLC to advise on the sale of its stake in Tysabri, a multiple sclerosis drug. It should have been a quick and relatively straightforward engagement: Cox, who is based in New York, had represented the company on eight transactions of more than $1 billion in the past seven years alone. But it would be a full 12 months before Cox finally finished the transaction, and not before dealing with a hostile takeover bid and the eventual sale of Élan itself. “This was by a stretch the longest transaction that I’ve ever worked on,” Cox says. “It was a long, difficult process.”
Everything started off well. Early negotiations with Élan’s joint venture partner on Tysabri, American biotech company Biogen Idec Inc., proved fruitful, and by February 2013 the principals struck a deal in which Biogen would pay $3.25 billion in cash for the drug—a humanized monoclonal antibody that works to slow down the progression of the physical disability caused by multiple sclerosis. Élan also secured a lucrative tiered royalty of up to 25 percent of future worldwide net sales of Tysabri, which in 2012 hit $1.6 billion.
