) --

Acorda Therapeutics

(ACOR) - Get Report

announced mixed results from two proof-of-concept studies Monday aimed at expanding the use of its multiple sclerosis walking drug Ampyra to include patients suffering from strokes and cerebral palsy.

In a study of 83 patients who had experienced a stroke at least six months prior to enrollment, use of twice-daily Ampyra significantly improved walking ability compared to a placebo, Acorda said in a statement. The company didn't provide detailed data on Ampyra's efficacy

Three patients reported seizures during the study. One seizure occurred in a patient treated with a placebo. The two other seizure cases involved patients on Ampyra, although one was deemed an intentional overdose and suicide attempt.

"There were clear efficacy signals in the

Ampya post-stroke deficits trial and we therefore plan to proceed with a clinical development program for this indication," said Acorda CEO Ron Cohen.

There are approximately 7 million stroke survivors in the U.S., with about half having some difficulty walking, according to the company.

In a separate trial enrolling 24 patients with cerebral palsy, Ampyra "suggested potential treatment activity" related to walking ability and hand strength, Acorda said. The data are still being analyzed to determine if the results are strong enough to justify additional clinical trials.

Ampyra sales in multiple sclerosis totaled $266 million in 2012.

"The post-stroke market is clearly large and would meaningfully expand Ampyra's potential beyond the current MS opportunity," writes ISI Group analyst Mark Schoenebaum, in an email to clients Monday morning. "Ampyra is currently annualizing at about $400M in the U.S. for MS. We calculate that every $50M in additional peak U.S. sales could increase our DCF by around $4-5 (assuming 2027 US patent expiry)."

Acorda shares were up 9% to $34.24 in Monday pre-market trading.

-- Reported by Adam Feuerstein in Boston.

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