Juvenile idiopathic arthritis (JIA) is the most common chronic pediatric rheumatic disease and can have long-term effects leading to disability in adulthood. Biologics are a new class of drugs increasingly used to treat JIA. The primary study objective was to determine the incremental costs of biologics per additional responder compared to conventional treatment (methotrexate).
A separate decision model was created for etanercept, infliximab, adalimumab, and abatacept. The study population consisted of polyarticular-course JIA patients with a prior inadequate response or intolerance to disease-modifying antirheumatic drugs (DMARDs). The effectiveness measure was the proportion of patients who had a treatment response at 1 year according to the American College of Rheumatology (ACR) Pediatric 30 (Pedi 30) improvement criteria. Direct and indirect costs were calculated in 2008 Canadian dollars. Incremental cost-effectiveness ratios and 95% confidence intervals (95% CIs) were calculated for each biologic agent using probabilistic sensitivity analyses.
The additional costs per additional ACR Pedi 30 responder at 1 year were $26,061 (95% CI $17,070, $41,834), $46,711 (95% CI $30,042, $75,787), $16,204 (95% CI $11,393, $22,608), and $31,209 (95% CI $16,659, $66,220) for etanercept, adalimumab, abatacept, and infliximab, respectively.
Biologics are more effective than methotrexate in achieving a short-term response in JIA patients with prior inadequate responses to DMARDs; however, this comes at a high annual cost. Adequate long-term data with respect to both safety and effectiveness are not currently available, nor are utility estimates. Such data will be important to estimate value for money for treating JIA with biologic drugs over the long term.