[P7.244] Dalfampridine Real World Utilization and Efficacy Assessment
Sylvia Klineova, Joshua Friedman, Colleen Farrell, Christine Hannigan, Fred Lublin, Stephen Krieger
New York, NY, USA
To assess utilization of dalfampridine and magnitude of walking speed improvement in clinical practice.
Two phase 3 trials showed approximately 35% of patients receiving dalfampridine were Timed 25 Foot Walk (T25FW) responders, with average improvement in walking speed of 25%. We examined if T25FW response rate and magnitude differ in clinical practice.
Single-center retrospective study evaluating all patients for whom dalfampridine was prescribed since approval, from March 2010 through August 2013. Inclusion criteria for T25FW analyses: diagnosis of MS, dalfampridine treatment ≥ 3 months, and minimum of two T25FW measurements within one year pre- and post- treatment.
Chart review identified 221 intention-to-treat (ITT) patients. Dalfampridine was shipped to 174 (78.7%), twelve of whom never began therapy. Thirty patients (13.5%) discontinued dalfampridine in < 3 months due to lack of subjective benefit. 67 patients (30.5%) had insufficient visits or documentation during the time window, and 6 patients (2.7%) were non-ambulatory at baseline. Fifty-three patients (23.9%) met our inclusion criteria for walking speed analysis, with mean T25FW of 9.5 seconds (range 3.8 to 66.3).
Twenty-nine of these patients (56.9%) showed improvement in T25FW speed, and 24 (53.8%) showed none. In 10 patients (18.9%), the T25FW improvement was < 10%. Eleven patients (20.8%) improved between 10 - 20%. Only 8 patients (15.1%) achieved a clinically meaningful threshold of > 20% improvement, comprising 3.6% of the 221 patients in the ITT population. Despite this, 47 of the 53 (88.7%) continued therapy at last point of follow up.
Our real world cohort demonstrated a lower rate and magnitude of T25FW improvement than was seen in clinical trials. Given that only a small minority of patients who continued on dalfampridine showed a clinically meaningful T25FW improvement, the T25FW may be an insensitive measure of actual therapeutic response to dalfampridine.
Category - MS and CNS Inflammatory Disease: Clinical Science
Thursday, May 1, 2014 3:00 PM
P7: Poster Session VII: Treatment of Specific Multiple Sclerosis Symptoms (3:00 PM-6:30 PM)