Single abobotulinumtoxinA injections over a 1-year period safely and effectively reduce muscle tone and improve walking speed in patients with chronic hemiparesis, according to a multicenter, double-blind, placebo-controlled study published in Neurology.
In this trial (ClinicalTrials.gov Identifier: NCT01249404), investigators randomly assigned patients with chronic hemiparesis to receive 1 lower limb injection consisting of either 1000 U abobotulinumtoxinA, 1500 U abobotulinumtoxinA, or placebo. Efficacy for reducing muscle tone was assessed using the Modified Ashworth Scale (MAS) in gastrocnemius-soleus complex (GSC) and physician global assessment (PGA).
Compared with placebo, participants receiving 1500 U abobotulinumtoxinA experienced a significantly greater MAS GSC change from baseline at 4 weeks (-0.8; P =.009). Additionally, there was a trend toward greater changes in PGA scores from baseline at 4 weeks among the 1000-U and 1500-U abobotulinumtoxinA groups vs placebo (P =.067 for both).
The investigators observed no significant differences between treatment groups and placebo with regard to improvements in walking speed. In the open-label period at cycle 4, week 4, the average MAS GSC change was -1.0, whereas average PGA was 1.9. The walking speed increased +25.3% (17.5, 33.2) during this same period.
Overall, abobotulinumtoxinA was found to have a good tolerability and safety profile.
According to the investigators, data from the open-label extension should be observed with caution because of the small number of participants in this portion of the study.
In addition to single abobotulinumtoxinA injections, the investigators suggest that “repeated abobotulinumtoxinA injections combined with a tailored rehabilitation program should be studied to determine whether even greater improvements over time could occur in chronic hemiparesis.”
Disclosures: The NCT01249404 clinical trial was sponsored by Ipsen, a manufacturer of abobotulinumtoxinA.
Gracies JM, Esquenazi A, Brashear A, et al. Efficacy and safety of abobotulinumtoxinA in spastic lower limb: Randomized trial and extension. Neurology. 2017;89:2245-2253.