Comparison of Botulinum Toxins Type A for Managing Pediatric Lower Limb Spasticity

AbobotulinumtoxinA improves tone and functional outcomes in pediatric patients with lower limb spasticity more than onabotulinumtoxinA, but both are comparable in tolerability in this patient population. This is according to a study in the Journal of Child Neurology.

European researchers identified a total of 10 randomized controlled trials that reported the efficacy and safety outcomes of botulinum neurotoxin type A for pediatric spasticity. The 12-week postinjection outcomes analyzed in the network meta-analysis included adverse events as well as outcomes on the Modified Ashworth Scale, Tardieu Scale spasticity grade, and Goal Attainment Scale (standard mean difference only).

Based on scores of the Modified Ashworth Scale at 12 weeks, abobotulinumtoxinA at 15 U/kg/leg was more effective for improving muscle tone than onabotulinumtoxinA at 4 U/kg/leg (-0.99; 95% CI, -1.34 to -0.64]) and onabotulinumtoxinA 4 U/kg/ leg+casting (-0.81; 95% CI, -1.16 to -0.46]). Additionally, abobotulinumtoxinA was numerically better for improving tone than onabotulinumtoxinA at 8 U/kg (-0.40; 95% CI, -0.67 to -0.14]).

AbobotulinumtoxinA at 10 U/kg/leg and 15 U/kg/leg was significantly more effective than onabotulinumtoxinA at 12 U/kg/leg for improving scores on the Goal Attainment Scale. Conversely, abobotulinumtoxinA was similar to other therapies based on the Tardieu Scale spasticity grade, and abobotulinumtoxinA was also similar to onabotulinumtoxinA at all doses with regard to rate of adverse events.

One limitation of this research was the small patient samples in the majority of the included studies and the inconsistency and/or lack of clarity regarding the efficacy and tolerability outcome measures across studies.

The researchers added that further work “is needed to understand why improvement on end points assessed in the above onabotulinumtoxinA studies did not systematically translate in a respective improvement on the Modified Ashworth Scale, Goal Attainment Scale, and Tardieu Scale spasticity grade where measured.”

Reference

Guyot P, Kalyvas C, Mamane C, Danchenko N. Botulinum toxins type a (BoNT-A) in the management of lower limb spasticity in children: a systematic literature review and Bayesian network meta-analysis [published online February 25, 2019]. J Child Neurol. doi:10.1177/0883073819830579