Fampridine treatment and walking distance in multiple sclerosis: A randomised controlled trial.

OBJECTIVE: To explore the benefits of modified-release fampridine on walking distance in MS.

METHODS: This was a randomised double-blind, placebo-controlled crossover trial of fampridine in 25 MS patients. The primary outcome measure was the six minute walk test (6MWT). A p-value<10% led to rejection of the null hypothesis.

RESULTS: The pre-specified criterion for statistical significance was met, with a 17m improvement in 6MWT in the treatment arm. In addition, baseline S2 accommodation, a nerve excitability parameter that reflects slow K+ channel activity, modified the effect of fampridine. For patients who had abnormally high S2 accommodation values, there was a 28m improvement in the 6MWT (p=0.04). In contrast, for patients with low S2 values, a 0m improvement was noted (p=1.0).

CONCLUSION: The study provides evidence that fampridine may improve walking distance. Nerve excitability assessment may be useful in selecting those patients who are most likely to gain benefit from fampridine.

SIGNIFICANCE: Fampridine may improve walking distance in MS. Nerve excitability assessment may assist in identifying those patients most likely to respond to fampridine.