OBJECTIVES: Canadian expenditures on glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) have increased significantly in recent years, correlated with regulatory approvals and direct-to-consumer advertising. This may also be explained by the use of these drugs “off reimbursement criteria” (use outside of funding criteria) given their efficacy in other indications (weight management). The use of GLP-1 RAs, publicly funded for type 2 diabetes mellitus (T2DM) in Canada, was analyzed to determine their utilization patterns and estimate their suspected use off reimbursement criteria.

METHODS: Drug claims were analyzed to describe GLP-1 RA claimants and expenditures. GLP-1 RA monotherapy versus combination (with other T2DM drugs) therapy usage and their suspected use off reimbursement criteria (non-T2DM), defined as GLP-1 RA use without a history of other T2DM drugs or glucose monitoring devices, were assessed.

RESULTS: Ozempic is the dominant GLP-1 RA (>99% market share) and its expenditures have increased from $13.5 million to $227 million from 2019-2021 (number of claimants increased 5-fold from 24,733 to 128,910 in this same period). Some patients may not be using Ozempic appropriately for T2DM, including a portion of the 17% using it as monotherapy and the 12% using it in combination with dipeptidyl peptidase-4 inhibitors in 2021. Increasing use of Ozempic can be partially attributed to non-T2DM claims. The proportion of claimants representing suspected non-T2DM use increased more than double from 4.2% in 2019 to 10.7% in 2021. Jurisdictions with the highest proportion of suspected non-T2DM use were those with less restrictive listing status or reimbursement criteria.

CONCLUSIONS: Formulary management strategies (prior authorization or prescriber audits) can promote the appropriate use of GLP-1 RAs. Future research in this field should assess if similar patterns are seen with private insurance, if non-T2DM GLP-1 RA use can be detected for individuals circumventing current funding criteria, and the effects of direct-to-consumer advertising on appropriate drug use.