PMH12 - A Cost-Effectiveness Analysis of Guanfacine Extended-Release Treatment in Pediatric Attention-Deficit/Hyperactivity Disorder

Abstract

Attention-deficit/hyperactivity disorder (ADHD) is a developmental disorder characterized by hyperkinesia, impulsivity, and impaired attention. At present, only the stimulant methylphenidate (MPH) and the non-stimulant atomoxetine (ATX) are covered under insurance for the treatment of ADHD in Japan. In 2007, the non-stimulant guanfacine extended-release (GXR) was approved for use in the US, and joint development of the drug has also progressed in Japan. However, a cost-effectiveness analysis (CEAs) has yet to be conducted on the use of GXR in Japan. In this study, we performed a CEA of GXR treatment in pediatric patients with ADHD in Japan. We constructed a Markov model to describe state transitions in ADHD, and conducted a CEA comparing the administration of GXR alone (0.075-0.12 mg/kg/day) with ATX alone (1.2 mg/kg/day). The analysis was conducted from the perspective of the public healthcare payer; reference cases comprised ADHD patients aged 6–18 years, and the study duration was one year. The quality-adjusted life year (QALY) was used as the effect measure, and the final result of the CEA was presented as an incremental cost-effectiveness ratio (ICER). Costs (excluding GXR price) were calculated using the medical fee points list, and the drug price for GXR was calculated using the mean price of the US, UK, Germany, and France. The QALY value included in the model was adopted from one reported in a published ADHD study. When compared with the administration of ATX alone, the administration of GXR alone was associated with both a higher cost (approximately US$67) and effect (0.007 QALY); the ICER was approximately US$9600/QALY. The results of this study indicate that when considering a willingness-to-pay threshold of US$50,000 per QALY, there is a high possibility that the use of GXR will be cost-effective as an ADHD treatment in Japan.