Trends in the Cost and Utilization of Publicly Dispensed Respiratory Inhalers in Ontario, Canada: A Repeated Cross-Sectional Study

Background: Ongoing renewal of patents for brand-name respiratory inhalers has substantially inflated the cost of respiratory disease treatment, imposing a financial strain on both public and private payers. While novel brand-name combination therapy inhalers and generic alternatives for Advair® and Flovent® were recently listed on public formularies, the cost implications remain unknown.

Objectives: To examine trends in the utilization and cost of respiratory inhalers reimbursed by the public payer in Ontario, Canada.

Methods: We conducted a repeated cross-sectional study among all individuals dispensed a respiratory inhaler through the public drug benefits program between January 1, 2003, to March 31, 2023. The following outcomes were reported per calendar quarter: 1) public payer spending on respiratory inhalers; 2) number of beneficiaries dispensed at least one respiratory inhaler; and 3) per-capita public payer spending. Costs were inflation-adjusted to 2023 Canadian dollars. Lastly, we used joinpoint regression analysis to characterize changes in per-capita public payer spending. All analyses were reported overall and stratified by drug class (e.g., inhaled corticosteroid and long-acting beta-agonist [ICS/LABA], long-acting muscarinic agents [LAMA]/LABA).

Results: Over the study period public payer spending on respiratory inhalers increased by 159.6% ($26,206,322 to $68,054,816), while the number of beneficiaries increased by 92.5% (155,893 to 300,074). Despite rising per-capita costs between Q1, 2003 ($168) to Q4, 2014 ($259), in Q2, 2015 (formulary listing of LAMA/LABA inhalers) the trend declined for the first time, decreasing by 1.38% and 4.07% per quarter between Q2, 2015 - Q2, 2017 and Q3, 2017 - Q2, 2018, respectively. Following Q3, 2018 ($191) per-capita spending increased by 4.38% per quarter until Q2, 2019 ($227). The final significant shift in the trend was noted in Q3, 2019 (formulary listing of ICS/LAMA/LABA), after which per-capita spending plateaued and ranged between $211 to $234 per quarter despite subsequent listing of generic alternatives for Advair® and Flovent®. When stratified by inhaler drug class, ICS/LABA ($33,844,484 in Q1, 2023) was the primary driver of overall costs, while per-capita cost was greatest for ICS/LAMA/LABA ($392 in Q1, 2023).

Conclusions: While formulary listing of combination therapy respiratory inhalers led to a reduction in public payer spending, listing of generic inhalers minimally impacted per-capita spending, in part due to the limited availability of generic alternatives. Regulatory reform should be considered to prevent patent prolongation, and further support introduction of generic inhalers.