Acorda Therapeutics Inc. initiated two Phase III trials of its lead product, Fampridine-SR, in chronic spinal cord injury.

Acorda, of Hawthorne, N.Y., designed the trials to evaluate both the safety and efficacy of Fampridine-SR in treating moderate to severe spasticity, which is experienced as involuntary stiffness or contraction of muscles.

"There are about 250,000 people with chronic spinal cord injury. Of those, 75 percent have permanent spasticity," Acorda President and CEO Ron Cohen told BioWorld Today.

The co-endpoints for the trial are improvements in the Ashworth Score, which specifically measures spasticity, and the Clinical Global Impression of Change score, which compares a subject's evaluation of improvement with a clinician's.

"The participants would be people with chronic spinal cord injury, defined as people who have been injured at least 18 months," Cohen said.

There is no upper limit, so the expected 360 enrollees may have been living with an injury as long as 15 or 20 years, he said.

"We're looking at people who already have healed from the original injury and are dealing with the deficiency that they are living with," he said.

Cohen said he expects the two trials to take about one year to complete.

"Our intention is to file as soon as possible after a successful outcome of these studies," he said.

Fampridine, or 4-aminopyridine, is designed to improve conduction in damaged nerves. Fampridine-SR is an oral, sustained-release formulation designed for twice-daily dosing. It works by blocking exposed potassium channels in demyelinated nerve processes, or axons, the company said.

Fampridine-SR also is in late Phase II trials in multiple sclerosis. The company has initial Phase II data in a double-blind study that showed the compound enabled faster walking.

"At present, we're not prepared to publicly give projections on the market," Cohen said. "In our view, it's a large market, certainly over $100 million."

Cohen said that by combining the market for spasticity and that for multiple sclerosis, "then you're talking about something quite substantial."

Acorda is developing Fampridine-SR under a license from Elan Corp. plc, of Dublin, Ireland. It obtained rights to develop it in spinal cord injury from the Canadian Spinal Research Organization in Richmond Hill, Ontario.

In first quarter of 2001, Acorda raised $39.7 million in two closings of a Series I financing round. At the time, Cohen said the money could last as long as two and a half years, taking it through clinical and preclinical development. Founded in 1995, Acorda operated as a virtual company until 1998. (See BioWorld Today, Jan. 10, 2001.)