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.