Efficacy and Tolerability of Long-Term, Open-Label, Mixed Amphetamine Salts Extended Release in Adolescents With ADHD

Objective Assess long-term tolerability and efficacy of once-daily mixed amphetamine salts extended release (MAS XR) for attention-deficit/hyperactivity disorder (ADHD) in adolescents (13–17 years of age). Methods Efficacy of MAS XR (10–60 mg/day) in 138 adolescents with ADHD was assessed in a 6-month, openlabel, extension study following participation in a 4-week, randomized, placebo-controlled trial of MAS XR. Efficacy was based on ADHD Rating Scale-IV (ADHD-RS-IV) scores and Clinical Global Impressions-Improvement (CGI-I) ratings at end point. Tolerability was based on reported adverse events, physical and laboratory examintions, vital signs, and electrocardiographic measures. Findings Patients exhibited sustained improvement in ADHD symptoms in this 6-month, open-label study of MAS XR 10–60 mg/day. End point ADHD-RS-IV total score was significantly decreased from baseline (-7.9; P<.0001); similar decreases were seen for hyperactivity/impulsivity (-4.0; P<.0001) and indttentiveness (-3.8; P<.0001). Based on CGI-I ratings, 60.9% of patients were very much/much improved, 33.3% were unchanged, 5.8% were much worse, and 0% were very much worse. The most common adverse events related to MAS XR were anorexia (24.6%), weight loss (24.6%), headache (14.5%), and nervousness (13.0%). Conclusion Long-term MAS XR therapy is generally well tolerated and exerts sustained control of ADHD symptoms in otherwise healthy adolescents.