Quality of life in subjects with upper- and lower-limb spasticity treated with incobotulinumtoxinA

Background: We evaluated quality of life among subjects with upper- and lower-limb spasticity who received escalating doses of incobotulinumtoxinA (total body doses up to 800 U) in the prospective, single-arm, dose-titration TOWER study.

Methods: In this exploratory trial, subjects (N = 155; 18-80 years of age) with upper- and lower-limb spasticity due to cerebral causes who were deemed to require total body doses of up to 800 U incobotulinumtoxinA received three consecutive injection cycles of incobotulinumtoxinA (400, 600, and up to 800 U), each with 12 to 16 weeks' follow-up. QoL was assessed using the EuroQol 5-dimensions questionnaire, three-level (EQ-5D), before and 4 weeks post-injection in each injection cycle and at the end of injection cycle 3.

Results: The mean EQ-5D visual analog scale scores of 155 participants continuously improved from study baseline to 4 weeks post-injection in all injection cycles (mean [standard deviation] change 6.7 [14.1], 9.6 [16.3], and 8.6 [17.0] for injection cycles 1, 2, and 3, respectively; p < 0.0001 for all, paired sample t-test). In general, among those with a change in the EQ-5D rating of their condition, the proportion of subjects with 'improvement' was greater than that with 'worsening' for individual EQ-5D dimensions across all injection cycles. At the end of injection cycle 3, the proportion of subjects rating their condition as 'normal' increased from study baseline for all dimensions, and there was a ≥ 46% reduction in the proportion of subjects with a rating of 'severe impairment'.

Conclusion: These preliminary results suggest that escalating incobotulinumtoxinA doses up to 800 U are associated with improvement in quality of life ratings in subjects with multifocal upper- and lower-limb spasticity, and form a basis for future comparator studies.

Trial registration: ClinicalTrials.gov, NCT01603459. Date of registration: May 22, 2012.