BARCELONA—Prolonged-release fampridine improves objective and subjective measures of walking in patients with multiple sclerosis (MS), according to research presented at the 31st Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS). The drug also may improve patients’ quality of life.
Rachel Farrell, PhD, a consultant at the National Hospital for Neurology and Neurosurgery in London, and colleagues enrolled 133 patients (93 females) with MS and severe walking impairment into a study to examine the long-term efficacy of prolonged-release fampridine on walking, quality of life, and functional ability when used in routine clinical practice. Participants were examined by neurologists and specialist physiotherapists in a specialist ambulation clinic. Study outcomes included Timed 25-Foot Walk (T25FW), MS Walking Scale (MSWS-12), the EuroQol 5-dimension instrument (EQ-5D-5L), functional goals of treatment, and walking aid use. Patients whose T25FW speed increased by 20% or more from baseline and whose MSWS-12 scores also improved were considered responders.
Participants’ mean Expanded Disability Status Scale score at baseline was 6.41. In all, 105 patients achieved responder status at two weeks. Mean baseline T25FW speed was 0.822 ft/s for responders and 0.934 ft/s for nonresponders.
At two weeks, mean T25FW speed improved by 83.3% from baseline in the responder group, compared with a deterioration of 2.73% among nonresponders. Responders continued to walk faster at 22 months (0.920 ft/s) than at baseline. The researchers also observed significant improvements in the MSWS-12 among responders (-21.7), but not among nonresponders (+5.7).
In addition, the EQ-5D-5L index improved significantly among responders (+0.114), compared with nonresponders (-0.046). Responders reported more anxiety or depression on EQ-5L-5D at baseline than nonresponders, but scored better on the other four domains of the index. After four months, 79% of patients had achieved their goals (eg, walking to the corner shop, reducing falls, increasing social activities, or doing housework). After 10 months, 55% of patients had maintained their goals, and a further 38% had achieved their goals.
The majority of patients required the same walking aids at the end of the study period. A total of 17 patients required fewer aids, and three patients required more assistance. “This [result] suggests that prolonged-release fampridine responders perform better functionally for up to 22 months of treatment,” said Dr. Farrell.
Side effects reported in the study were the same as those described in phase III and IV trials of fampridine. They included insomnia, urinary tract infections, gastrointestinal side effects, dizziness, and headaches.
“This cohort has a higher responder rate than that of pivotal trials. This [result] may be due to the severity of their walking impairment and the open-label nature of this study,” said Dr. Farrell. “This [finding] brings into question the current practice of using a 20% improvement as the threshold for clinical significance.” Overall, “the results of this study validate the utility of prolonged-release fampridine in improving walking of people with MS in routine clinical practice,” she concluded.