Efficacy and Safety of Botulinum Toxin Type A in Spasticity Caused by Spinal Cord Injury: A Randomized, Controlled Trial

BACKGROUND: Baclofen is approved by the US FDA to treat spasticity, but its sustained use may cause drug addiction. The objective of this study was to compare the efficacy and safety of botulinum toxin type A versus baclofen in spasticity. MATERIAL/METHODS: A total of 336 patients who had spasticity caused by spinal cord injury were enrolled in a randomized (in 1: 1: 1: ratio) for placebo, controlled trial. Patients had received baclofen (BA group, n=112), local intramuscular injection of 500 U Botulinum toxin type A (BTI group, n=112), or physical therapies alone (placebo group, n=112). Modified Ashworth scale (mAS) score, disability assessment scale (DAS) score, modified medical research council (mMRC) score, the Barthel Index (BI) score, and treatment-emergent adverse effects were evaluated during the follow-up period. Wilcoxon test or one-way ANOVA/Tukey post hoc tests were performed at 95% of confidence level. RESULTS: Baclofen (1.504±0.045 vs. 1.53±0.06, p=0.003, q=4.068) and botulinum toxin type A (1.49±0.09 vs. 1.528±0.15, p=0.0224, q=3.5541) had improved mAS scores after 2 weeks. Baclofen had a more strongly improved DAS score than botulinum toxin type A at 4 (p=0.0496, q=3.48) and 6 (p<0.0001, q=6.48) weeks. Baclofen and botulinum toxin type A had consistently improved BI scores. Baclofen caused asthenia and sleepiness, while botulinum toxin type A caused bronchitis and elevated blood pressure. CONCLUSIONS: Botulinum toxin type A may be an effective therapeutic option for spasticity caused by spinal cord injury.