A day after reporting a failure in the clinic with a mid-stage multiple sclerosis compound, Biogen Idec has responded by buying certain rights to Acorda Therapeutics’ investigational MS drug Fampridine-SR.

Biogen has acquired the rights to develop and commercialise Fampridine-SR (4-aminopyridine) outside the USA. The drug is a novel, oral sustained-release compound being developed to improve walking ability in people with MS, the companies noted.

Under the terms of the agreement, Acorda will receive an upfront payment of $110 million and up to $400 million more based on the successful achievement of future regulatory and sales milestones. Biogen will also make tiered, double-digit royalty payments to Acorda which will make payments to Ireland’s Elan Corp, which will continue to manufacture commercial supply of Fampridine-SR. Biogen and Elan already have a partnership in place covering the MS blockbuster Tysabri (natalizumab).

Biogen chief executive Jim Mullen said that the deal is part of a plan to “expand our global MS leadership” and “we believe Fampridine-SR has the potential to become an important oral therapy that may help improve the walking ability of a wide range of patients.”

Acorda is keeping the rights to Fampridine-SR in the USA and the Food and Drug Administration is giving the treatment a priority review. A Prescription Drug User Fee Act date of October 22 this year has been scheduled. The European Medicines Agency had previously told Acorda that it may proceed with its marketing authorisation application, though the drug has yet to be filed.

Despite signing up a major partner, shares of Acorda fell amid fears that Biogen will focus more on its other MS treatments, such as Tysabri and Avonex (interferon beta-1a), than promoting Fampridine-SR. The deal was sealed a day after Biogen and partner UCB pulled a Phase II study of CDP323 for the treatment of relapsing MS after the drug did not benefit patients as much as expected compared to placebo after six months.