Jan. 22, 2010 - The FDA has approved Ampyra (dalfampridine), which improves walking ability in adults with multiple sclerosis (MS).

About three-fourths of MS patients have trouble walking, and 70% of those with walking problems say this is the most challenging aspect of their disease.

Ampyra is taken with other MS drugs and does not keep MS from getting worse, says Andrew D. Goodman, MD, director of the MS center at the University of Rochester, N.Y. Goodman led some of the clinical trials that led to the drug's approval.

"A large segment of people with MS have difficulty walking, and we have found that it helps some patients -- 35% in one study and 42% in another -- to consistently walk faster," Goodman tells WebMD. "Among those who do walk faster, they improve about 25% from baseline. These patients said they could walk longer distances, be on their feet longer, climb stairs better, and better perform other walking functions."

Ampyra does not change the course of MS disease, but enhances nerve function.

"There is no indication this type of treatment slows the progressive nature of the disease process," Goodman says. "But there is every indication that at whatever level of function an MS patient may have, there may still be room for improvement with this type of treatment."

The drug is by no means risk-free. Ampryra is a new formulation of a drug called fampridine, which was originally used as a bird poison.

Some 20 years ago, test tube studies suggested that fampridine could improve nerve conduction. Since then, some neurologists -- Goodman is not one of them -- have ordered the drug from compounding pharmacies for their MS patients.

At doses higher than the approved dose -- 10 milligrams twice daily -- Ampyra can cause seizures. The drug cannot be used by MS patients with a history of seizure, or by those with moderate-to-severe kidney disease. The drug cannot be taken with other forms of fampridine.

Side effects seen in clinical trials include urinary tract infection, insomnia, dizziness, headache, nausea, back pain, loss of muscle strength, balance disorder, multiple sclerosis relapse, tingling or numbness in the extremities, nose or throat inflammation, constipation, upset stomach, and throat pain.

Ampyra is made by Acorda Therapeutics of Hawthorne, N.Y. Acorda says the drug should be available in the U.S. in March. It will be sold through a network of specialty pharmacies coordinated by Ampyra Support Services at 888-881-1918.

http://www.webmd.com/multiple-sclerosis/news/20100122/ms-drug-ampyra-gets-fda-nod