Acorda Therapeutics has been boosted by the news that regulators in the USA have given the go-ahead to Ampyra as a treatment to improve walking in multiple sclerosis patients.

The US Food and Drug Administration has approved Ampyra (dalfampridine), which has demonstrated efficacy in people with all four major types of MS (relapsing remitting, secondary progressive, progressive relapsing and primary progressive). It can be used alone or with existing MS therapies, including immunomodulators.

Difficulty walking is often cited by those with MS as “one of the most pervasive and challenging aspects of their disease", said Ron Cohen, Acorda’s chief executive. He added that Ampyra, which was previously referred to as fampridine-SR, is the only medication indicated for this use.

The approval was expected as last October the FDA’s Peripheral and Central Nervous System Drugs Advisory Committee voted 12 to one on Ampyra’s effectiveness and 10 to two (with one abstention) that it is “clinically meaningful and can be safe for use”. Acorda noted that a risk evaluation and mitigation strategy programme will inform patients about the serious risks, including seizures, associated with use of higher than recommended doses of the extended-release pill.

Acorda added that Ampyra will be commercially available in the USA in March and the company plans to double the number of sales reps to promote the product, which will be manufactured by Elan Drug Technologies using its MXDAS technology. Partner Biogen Idec filed the drug in Europe earlier this month.