Pharmacology and clinical efficacy of dalfampridine for treating multiple sclerosis

Multiple sclerosis (MS) is the most frequent cause of neurological impairment and sustained disability in young adults. Currently approved disease-modifying drugs do not directly ameliorate the most common symptoms, such as walking impairment. Dalfampridine (DAL), currently approved in all forms of MS, might represent an answer to unmet needs in the symptomatic treatment of MS.

The main pharmacological and clinical properties and safety issues of DAL, an extended-release formulation of 4-aminopyridine (4-AP), a broad-spectrum voltage-dependent potassium channel blocker, are described. Relevant publications were identified from a search of PubMed from 1966 to June 2014 (search terms 'dalfampridine OR fampridine OR 4-aminopyridine). DAL, 10 mg twice daily, improves walking ability in approximately one-third and walking speed in about 25% of patients, independently from disease course, compared with placebo; it also improves leg strength. Treatment is generally well tolerated, although there is a dose-dependent increased risk of seizures, especially with dosages > 10 mg twice daily.

DAL represents an option in the symptomatic treatment of MS. Improved ambulation can impact quality of life, motivation and adherence, enhancing the successful management of MS. It has still to be established whether this favorably impacts costs associated with MS.