Impact of abobotulinumtoxinA treatment on the assisting hand assessment in children with hemiparesis due to cerebral palsy: Results from an international, Phase 3, pivotal study (abstract)

Background and Aims: When used in conjunction with occupational therapy, the aim of botulinum toxin treatment in children with upper-limb spasticity is to produce a selective reduction in muscle spasticity while optimising the effects of therapies used for improving range of motion, enhancing motor ability and functional skills. We assessed effect of a single abobotulinumtoxinA injection cycle on bimanual performance in children with hemiparesis due to cerebral palsy (CP).

Methods: This was a double-blind, repeat-treatment (<=4 cycles over 1 year) study (NCT02106351). During Cycle 1, children (2-17 years) with CP and spasticity in >=1 upper-limb were randomized to injections of abobotulinumtoxinA 2U/kg (low-dose), 8U/kg and 16U/kg into the primary target muscle group (PTMG; elbow or wrist flexors). All children participated in an individualized home-exercise therapy program. For the subset of children with hemiparesis treated at certified centers, the Assisting Hand Assessment (AHA) was performed at Baseline and Week 6.

Results: Overall 212 children were enrolled, of which 160 had hemiparesis and 92 had AHA assessments at baseline. Mean±SD baseline AHA scores (2U/kg, 8U/kg, 16U/kg) were 43.8±20.5, 46.2±16.7 and 49.3±17.1, respectively. Adjusted mean±SE [95%CI] changes in the AHA scores from baseline to Week 6 of Cycle 1 (n=83) were 4.6±1.8 [1.0, 8.2], 4.8±1.6 [1.6, 8.0] and 3.7±1.6 [0.4, 6.9], respectively. There were no significant differences between higher doses and the 2U/kg low-dose.

Conclusions: By Week 6 post-treatment, abobotulinumtoxinA combined with an individualized home-exercise therapy program provided some improvement in bimanual performance in children with hemiparesis due to CP.