Efficacy and Safety of Botulinum Toxin Type A in treating Upper Limb Spasticity in Post-stroke Patients : A Multicenter, Double-blind, Placebo-controlled Trial followed by an Open-label Trial / The Japanese Journal of Rehabilitation Medicine

ABSTRACT

Objective: To evaluate the efficacy and safety of botulinum toxin type A (BTXA) in Japanese patients with post-stroke upper limb spasticity in a multicenter, randomized, double-blind, single dose, placebo-controlled study (double-blind phase) followed by an open-label, multiple dose extension (open-label phase). Methods: One hundred and nine patients with upper limb spasticity were randomized to receive a single treatment with either a lower dose (120-150 Units ; U), higher dose (200-240U) BTXA or placebo into upper limb muscles in the double-blind phase. These treatments were administered to improve wrist and finger flexion for all patients and thumb flexion in patients with thumb spasticity. Patients who met the re-injection criteria received up to 3 repeated treatments of BTXA (200-240U) into their upper limb muscles with at least 12 weeks between treatments in the open-label phase through 48 weeks. Results: In the double-blind phase there was significant improvement from baseline spasticity on the Modified Ashworth Scale (MAS) wrist score between the higher dose BTXA and placebo groups, with a mean difference in the area under the curve (AUC) of -6.830 (<i>p</i><0.001, t test). The MAS wrist score further decreased from baseline in all repeat treatment cycles of BTXA in the open-label phase. No clinically relevant difference was noted in the frequency of treatment-related adverse events between BTXA-treated and placebo-treated patients during the study period. Conclusions: BTXA injections reduced spasticity in the upper limb muscles from the first treatment with continued long-term efficacy. Our results suggest that BTXA injections are safe and effective for the long-term treatment of post-stroke upper limb spasticity.