HAWTHORNE, N.Y. (

TheStreet

) -- Drug reviewers working for the Food and Drug Administration questioned whether

Acorda Therapeutics'

(ACOR) - Get Report

drug Amaya improves the walking ability of multiple sclerosis patients in a meaningful way, according to a review of the drug posted to the agency's Web site Friday.

The FDA is convening an advisory panel meeting on Oct. 14 to review Acorda's drug Amaya.

In its review of the drug, the FDA acknowledges that Acorda conducted two phase III studies of Amaya in multiple sclerosis patients, both of which met their primary endpoint of improving patients' ability to walk.

However, the FDA notes that, "it appears that the clinical meaning of the differences seen on the primary outcomes is in question."

Secondary endpoints of the pivotal Amaya studies were also "inconsistent and gave inconsistent results, and indicated a very limited effect on walking speed," the FDA said.

The FDA also raised questions about Amaya's safety, particularly the drug's link to seizures at higher doses.

Acorda conducted its phase III studies of Amaya under a Special Protocol Assessment agreement with the FDA, which means the agency agreed with the design of the studies before they started.

Biogen Idec

(BIIB) - Get Report

is Acorda's marketing partner for Amaya.

In an unusual step, the FDA added a disclaimer to the top of its review, which states: "The FDA background package often contains assessments and/or conclusions and recommendations written by individual FDA reviewers. Such conclusions and recommendations do not necessarily represent the final position of the individual reviewers, nor do they necessarily represent the final position of the Review Division or Office."

Acorda shares were down 10% to $19.86 in pre-market trading.

Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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