Long-term effects of dalfampridine in patients with multiple sclerosis
Dalfampridine is an extended release formulation of 4-aminopyridine and it is the only approved agent for the symptomatic treatment of impaired mobility in patients with MS. Dalfampridine is a potassium channel blocker which is thought to block voltage-sensitive potassium channels on nerve fibres exposed upon demyelination. This reduces abnormal potassium outward currents, improving conduction, prolonging action-potential duration and increasing the release of neurotransmitters.
This study looks at the short and long term effects of dalfampridine on motor and cognitive assessment parameters in 52 MS patients with an expanded disability status scale (EDSS) between 4.0-7.0 over a period of nine to 12 months. Assessments carried out at the start of treatment, as well as at two weeks and after nine to 12 months of treatment, include walking ability, multiple sclerosis functional composite (MSFC), cognitive and motor fatigue and evoked potentials. 60% of patients remained on treatment after nine to 12 months.
Results showed that two weeks after starting treatment there were significant improvements in the timed-25 foot walk test, maximum walking distance, motor and cognitive fatigue and these results persisted after 9-12 months. In contrast, the effects on velocity were observed only after 2 weeks, while improvement in PASAT was only observed after 9-12 months.
Therefore this study demonstrates both short and long term effects of dalfampridine in patients with MS.
: Ruck T, Bittner S
: J Neurol Sci. 2013 Nov 16. pii: S0022-510X(13)03040-2. doi: 10.1016/j.jns.2013.11.011. [Epub ahead of print]
Read the abstract