98. AbobotulinumtoxinA (Dysport) in the treatment of adults with upper limb spasticity in a randomized, double-blind, placebo-controlled study

Abstract

Introduction and Objectives: Few extensive studies have assessed the effects of botulinum neurotoxin A in adults with upper limb spasticity (ULS) poststroke/traumatic brain injury (TBI) on muscle tone, spasticity, active range of motion (AROM), and function. The aim of this study was to assess the efficacy and safety of abobotulinumtoxinA (Dysport) in hemiparetic adults with ULS poststroke/TBI. Methods: In this phase 3, prospective, double-blind, placebo-controlled study, 243 patients (34 sites, 9 countries) were randomly assigned (1:1:1) to Dysport 500 or 1000 U or placebo. The primary objective was assessment of upper limb muscle tone (Modified Ashworth Scale; MAS) in the primary targeted muscle group (PTMG; finger, wrist, or elbow flexors). Other measures included spasticity (Tardieu Scale), AROM, ease of applying splint (EOS), clinical benefit (Physician Global Assessment; PGA), and subjective function (Disability Assessment Scale; DAS). Results: Four weeks postinjection, a higher proportion of patients achieved a ≥1 point improvement in MAS with both Dysport doses compared with placebo (placebo, 22.8%; 500 U, 73.8%; 1000 U, 78.5%; P<0.0001 vs placebo). Finger flexors were the most common PTMG across treatment groups (52% to 61%). For finger flexors, mean (standard error of mean; SEM) gain in spasticity angle was significantly improved with Dysport vs placebo at 500 U (27.3° [5.9]; P<0.01) and at 1000 U (29.5° [5.9]; P<0.01). This was associated with significantly improved active finger extension (23.9° [4.2]; P<0.0001 for 500 U and 17.6° [4.5]; P<0.01 for 1000 U). Similar results were observed for wrist and elbow flexors. EOS and PGA significantly improved at both doses; 50% (500 U) and 62% (1000 U) of patients improved on DAS (≥1 grade decrease from baseline) for the principal treatment target. Both doses were well tolerated, and the safety profile was consistent with previous experience with Dysport. Conclusions: Dysport improved muscle tone, spasticity, and AROM in the spastic upper limb at week 4; clinical benefit was also observed, based on PGA and DAS.