Petr Kaňovský, Elie P. Elovic, Michael C. Munin, Angelika Hanschmann, Irena Pulte, Michael Althaus, Reinhard Hiersemenzel, Christina Marciniak
Faculty of Medicine and Dentistry and University Hospital, Palacký University Olomouc, Olomouc, Czech Republic. E-mail: petr.kanovsky@fnol.cz
DOI: 10.2340/16501977-2760

Objective: This post hoc analysis assessed the impact of repeated incobotulinumtoxinA injections on muscle tone, disability, and caregiver burden in adults with upper-limb post-stroke spasticity.
Design: Data from the double-blind, placebo-controlled main period and three open-label extension cycles of two Phase 3, randomized, multicentre trials were pooled.
Methods: Subjects received incobotulinumtoxinA 400 Units at 12-week intervals (±3 days) (study 3001, NCT01392300) or ≤ 400 Units at ≥12-week intervals based on clinical need (study 0410, NCT00432666). Ashworth Scale (AS) arm sumscore (sum of elbow, wrist, finger and thumb flexor, and forearm pronator AS scores), Disability Assessment Scale (DAS), and Carer Burden Scale (CBS) scores were assessed.
Results: Among 465 subjects, from study baseline to 4 weeks post-injection, mean (standard deviation) AS arm sumscore improved continuously: main period, –3. 23 (2. 55) (placebo, –1. 49 (2. 09)); extension cycles 1, 2, and 3, –4. 38 (2. 85), –4. 87 (3. 05), and –5. 03 (3. 02), respectively. DAS principal target domain responder rate increased from 47. 4% in the main period (placebo 27. 2%) to 66. 6% in extension cycle 3. Significant improvements in CBS scores 4 weeks post-injection accompanied improved functional disability in all cycles.
Conclusion: IncobotulinumtoxinA conferred sustained improvements in muscle tone, disability, and caregiver burden in subjects with upper-limb post-stroke spasticity.

Spasticity (muscle overactivity) often occurs in patients after stroke and may lead to further disability. The results of 2 clinical trials were used to assess the effect of incobotulinumtoxinA injections (maximum dose used per injection session 400 Units) on arm and hand spasticity in patients after stroke. This study looked at the impact of treatment on disability and the burden on carers. The results from 4 treatment cycles were assessed. There was a continuous decrease in spasticity, together with improvements in disability in all treatment cycles. The burden on those who cared for patients also decreased. We showed that repeated incobotulinumtoxinA treatment across 4 cycles led to a decrease in spasticity, patient disability and burden on carers.