Acorda Therapeutics has discontinued further development of Ampyra (dalfampridine) to treat patients with post-stroke walking difficulties, the company said Nov. 21. The drug is currently approved to improve walking in people with multiple sclerosis.
The New York-based biotech company said its MILESTONE clinical study did not show sufficient drug efficacy to support further post-stroke work, failing to separate from placebo.
Acorda now plans to focus its R&D resources on developing the late-stage Parkinson's disease therapies, CVT-301 and tozadenant, along with other early-stage assets, Acorda CEO Ron Cohen said in the company statement.
Ampyra is one of only three FDA-approved products marketed by Acorda, and is the biotech's flagship product. Exploring an indication for post-stroke walking difficulties was meant as life cycle management to expand the use of the top-seller. Its failure, then, could weigh on Acorda's revenue growth plans.
Yet an impending decision on an inter partes review of a patent challenge to Ampyra hangs over those rising sales, threatening Acorda's franchise drug. Cohen, speaking on an earnings call last month, said Acorda expects a decision from the Patent Trial and Appeal Board in March 2017.
While expressing disappointment at Ampyra's trial failure, Cohen said Acorda had "successfully diversified" its pipeline to account for this risk. In January, for example, Acorda acquired the Finnish firm Biote, adding two Parkinson's drugs to its portfolio.
Acorda did note that the failed study confirmed a potentially viable once-a-day formulation of Ampyra, which could give it a more convenient dosing option. Currently, the company markets twice-daily extended-release tablets of Ampyra.
Despite the initial drop of Acorda's stock on the news, industry analysts at Leerink and RBC Capital Markets agreed with Cohen's outlook, indicating expectations for Ampyra were low for the stroke program.