International Journal of Neurorehabilitation

Incobotulinumtoxina (Xeomin®) Versus Onabotulinumtoxina (Botox®): Evaluation of Clinical Onset of Action with Rating Scales and Electroneurography

Abstract

Lucia Mastromauro, Paolo Trerotoli, Ersilia Romanelli, Riccardo Giuseppe Marvulli and Giancarlo Ianieri

Onset of action, duration and maximum efficacy of different botulinum toxin type A (BoNT/A) preparations have been compared mainly in in vitro studies. This single-center open study compared onset of action of the two BoNT/A preparations onabotulinumtoxinA (complex size 900 kDa) and incobotulinumtoxinA (free of complexing proteins, 150 kDa) in patients with spasticity after cerebral stroke over a 15-day treatment period. Outcome measures were changes in muscle tone, increase in passive extension of the elbow, changes in limb functionality, and variation of the amplitude of the compound muscle action potential (cMAP) determined by electroneurography. A total of 108 patients (mean age 64.8 ± 11.3 years) were included in the study, 54 in each treatment arm. Muscle tone, elbow motion range, and limb function significantly improved in both groups from baseline to day 15 after BoNT/A injection (p<0.0001). Improvements were significantly greater under incobotulinumtoxinA compared to onabotulinumtoxinA after 7 treatment days (p<0.0001) but were comparable after 15 days. Regarding cMAP amplitude, a faster reduction in the first 7 treatment days with no further significant reductions during the next week was observed for in cobotulinum toxinA patients, whereas on a botulinum toxinA patients showed a slower, progressive reduction in action potential resulting in comparable values between the two groups after 15 days. Overall, the efficacy of both BoNT/A preparations was comparable two weeks after injection.