​Did a Non-Medical Biosimilar Switching Policy Cause an Increase in Non-Biologic/Biosimilar Health Care Resource Utilization or Cost in Patients With Inflammatory Arthritis?

Abstract

This study aimed to evaluate the impact of a series of policies that mandated switching patients with inflammatory arthritis (IA) from an originator biologic to a biosimilar in British Columbia, Canada, on health care resource use and cost. The health data of patients with IA were obtained from five linked administrative databases held by Population Data BC from January 2013 to December 2022. Our analysis focused on trends in monthly average use and costs of four care resources: physician services, hospital services, emergency department visits, and concomitant drug use. Using interrupted time series analysis, we evaluated the impact of switching policies targeting (1) infliximab or etanercept and (2) adalimumab on total health care costs, excluding biologic and biosimilar costs. We included 3,150 patients in the study. Hospital and physician services accounted for the majority of the total care cost for patients with IA. We found no evidence of any increases in physician services, hospital services, emergency department visits, or concomitant drug use after either nonmedical switch policy. We also found no significant change in level and trend in total health care costs for both policies: infliximab or etanercept (level -$40, 95% confidence interval [CI] -$99 to $19; trend $5.42, 95% CI -$0.62 to $11.46) and adalimumab (level -$34, 95% CI -$139 to $70; trend -$8.97, -$17.94 to $0.00). Nonmedical biosimilar switching policies did not lead to increases in other health care service use and costs.