RESUMEN
BACKGROUND: Poststroke spasticity affects motor function and the ability to perform activities of daily living, with the potential to affect quality of life (QoL) and increase caregiver burden. OBJECTIVE: To investigate the effect of repeated incobotulinumtoxinA treatment on spasticity-associated functional disability, caregiver burden, and QoL in the 36-week open-label extension of the phase 3 PURE study (NCT01392300). DESIGN: Open-label extension period of a prospective, double-blind, placebo-controlled, randomized, multicenter study. SETTING: Forty-six investigation sites in seven countries (Czech Republic, Germany, Hungary, India, Poland, Russia, United States). PARTICIPANTS: Adults, aged 18-80 years, ≥12 months since last botulinum neurotoxin injection or entirely toxin naïve, with median poststroke upper-limb spasticity of >2 years' duration. METHODS: Participants who completed the 12-week, double-blind main period could enter the open-label extension and receive up to three additional incobotulinumtoxinA treatments (fixed total dose 400 U at 12-week intervals) into the affected muscles of one upper limb. MAIN OUTCOME MEASURES: Functional disability (Disability Assessment Scale; DAS), caregiver burden (Carer Burden Scale), and quality of life (QoL; EuroQol [EQ] 5-dimensions three-level [EQ-5D-3L]). RESULTS: The open-label extension included 296 treated patients. Mean DAS score for the principal target domain improved significantly from the main period baseline to the end-of-study visit (P < .0001). Carer Burden Scale scores also significantly improved from the main period baseline to the end-of-study visit (P < .05 for all caregiving activities except "applying a splint"). At the end-of-study visit, versus the main period baseline, 19.7%-33.3% of patients experienced improvements for each parameter on the EQ-5D-3L, except "mobility," with significant improvement in EQ-5D visual analog scale scores (P < .001). CONCLUSIONS: Repeated incobotulinumtoxinA treatments at 12-week intervals in participants with chronic poststroke upper-limb spasticity resulted in significant improvements in QoL, as well as significant reductions in upper-limb functional disability and caregiver burden.
Asunto(s)
Toxinas Botulínicas Tipo A , Espasticidad Muscular , Fármacos Neuromusculares , Accidente Cerebrovascular , Extremidad Superior/fisiopatología , Actividades Cotidianas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Toxinas Botulínicas Tipo A/uso terapéutico , Carga del Cuidador , Método Doble Ciego , Humanos , Persona de Mediana Edad , Espasticidad Muscular/tratamiento farmacológico , Espasticidad Muscular/etiología , Fármacos Neuromusculares/uso terapéutico , Estudios Prospectivos , Calidad de Vida , Accidente Cerebrovascular/complicaciones , Resultado del Tratamiento , Adulto JovenRESUMEN
INTRODUCTION: The objective of the study was to investigate the efficacy and safety of repeated incobotulinumtoxinA injections for the treatment of upper-limb post-stroke spasticity in adults. METHODS: Adults 18-80 years of age with post-stroke upper-limb spasticity who completed the 12-week randomized, double-blind, placebo-controlled main period (MP) of a phase 3 trial (NCT01392300) were eligible to enrol in the 36-week open-label extension period (OLEX). The OLEX included three treatment cycles at fixed 12-week injection intervals; subjects were injected with 400 U incobotulinumtoxinA into the affected upper limb. Efficacy assessments included evaluation of muscle tone using the Ashworth Scale (AS) and the Global Impression of Change Scale (GICS) assessed by the investigator, subject, and caregiver. The incidence of adverse events (AEs) was monitored throughout the OLEX. RESULTS: A total of 296 of 299 subjects (99.0%) who completed the MP received incobotulinumtoxinA in the OLEX, and 248 subjects completed the 36-week OLEX. The proportion of subjects with at least a 1-point improvement in AS score from each incobotulinumtoxinA treatment to the respective 4-week post-injection visit ranged by cycle from 52.3% to 59.2% for wrist flexors, 49.1% to 52.3% for elbow flexors, 59.8% to 64.5% for finger flexors, 35.5% to 41.2% for thumb flexors, and 37.4% to 39.9% for forearm pronators (P < 0.0001 for all). Over 90% of subjects were assessed by the investigator to be at least minimally improved (4 weeks post-injection) on the GICS during each injection cycle; 61.0% in the 1st cycle, 58.2% in the 2nd cycle, and 57.4% in the 3rd cycle were considered much improved or very much improved on the GICS. Three percent of subjects (9/296) reported treatment-related AEs; the most frequently reported were pain in the extremity (n = 2, 0.7%) and constipation (n = 2, 0.7%). Serious AEs were reported by 22 subjects (7.4%); however, none were considered treatment-related. CONCLUSIONS: Repeated injections of incobotulinumtoxinA for the treatment of post-stroke upper-limb spasticity led to significant improvements in muscle tone and investigator's global impression of change. Treatment was well tolerated, with no serious treatment-related AEs. FUNDING: Merz Pharmaceuticals GmbH.