Combined walking outcome measures identify clinically meaningful response to prolonged-release fampridine

BACKGROUND: Gait impairment is common in multiple sclerosis (MS) and negatively impacts patients’ health-related quality of life (HRQoL). Prolonged-release fampridine (PR-fam) improves walking speed, but it is unclear which walking measures are the most suitable for identifying treatment response. Our aim was to assess the effect of PR-fam and the outcome measures that best identify short- and long-term clinically meaningful response. METHODS: We conducted a prospective study in 32 MS patients treated with PR-fam for a year. The assessments at 2 weeks, 3, 6 and 12 months included: timed 25-foot walk (T25FW), 6-minute walk test (6MWT), MS Walking Scale-12 (MSWS-12), a five-level version of the EuroQoL-5 dimensions, and accelerometry. PR-fam response was defined as an improvement in T25FW ⩾20%. RESULTS: Twenty-five (78%) patients were considered responders after 2 weeks of PR-fam and improved significantly in all measures. Responders to T25FW and MSWS-12 (n = 19) showed a significant improvement in HRQoL and accelerometer data compared with responders only to T25FW (n = 6). At 1 year, 15/20 (75%) patients remained responders, but only those with permanent response to T25FW and MSWS-12 (n = 8; 53%) showed a significant improvement in 6MWT and HRQoL. CONCLUSION: The combination of T25FW and MSWS-12 identify better those patients with a clinically significant benefit of PR-fam.