Phase III trials shows Vyvanse (Shire) effective in children and adolescents with ADHD

Results from a Phase III extension study of Vyvanse (lisdexamfetamine dimesylate), from Shire, show that after 6 months of treatment, a significantly lower proportion of subjects with ADHD experience treatment failure compared to those on placebo. This study was designed to evaluate the long-term efficacy and safety of Vyvanse for the treatment of ADHD in children and adolescents aged 6 to 17, and as an extension to the European Phase III study of the efficacy and safety of LDX in this population. Patients were give Vyvanse for at least 26 weeks before entering a 6-week randomised withdrawal period, in which they took either Vyvanse or placebo. Results showed maintenance of efficacy in children and adolescents who continued to receive Vyvanse: there were a significantly lower proportion of ADHD treatment failures (13.5%) in this group, compared with placebo (65.8%); and the majority of placebo-treated subjects who met protocol-defined ADHD symptom relapse criteria did so within 2 weeks following randomisation. Treatment-emergent adverse events were also consistent with those reported in other Vyvanse studies in ADHD. This study is a critical element of the European submission package. A European MAA for Vyvanse was accepted for review in January 2012.