Additional subgroup analysis of onabotulinumtoxinA phase III trial in post-stroke patients with upper limb spasticity

Trial description: Patients with spasticity are highly heterogeneous, and treatment goals vary from patient to patient. Modified Ashworth Scale (MAS) is an established tool to assess spasticity (muscle tonus), but reduction of MAS scores per se does not always signify meaningful improvement for each patient, and should not be the treatment goal. In the phase III trial of upper limb spasticity conducted in Japan, Disability Assessment Scale (DAS) was used to assess four domains of functional impairment (Hygiene, Dressing, Pain, and Limb Position), and one of them was selected as "principal therapeutic target" by patients. In this additional subgroup analysis, the patients will be stratified according to their target (treatment goal), and the degree of their goal attainment will be assessed. The stratification is expected to result in the exclusion of patients with little or no impairment in each domain, and thus show improvement after injections more clearly. This analysis will be yet another piece of evidence to suggest the importance of evaluating the effects of spasticity treatment in the context of goal attainment.