Healthcare Cost Trends in New Users of SGLT-2i, DPP-4i and GLP-1 RA for Type 2 Diabetes: An Observational...

To analyse the healthcare cost trajectories following the initiation of glucagon-like peptide-1 receptor agonist (GLP-1 RA), sodium-glucose cotransporter-2 inhibitor (SGLT-2i) or dipeptidyl peptidase-4 inhibitor (DPP-4i) therapy in patients with type 2 diabetes.

We conducted a difference-in-difference study using member-level claims data from a national pharmacy benefit manager. Treatment-naïve patients were categorised into three groups based on the drug they initiated first. The first fill date in 2020 or 2021 was the index date, with a one-year look-back period and 2 years of follow-up. Propensity score weighting balanced the groups. We used generalised estimating equations to analyse year-over-year changes in per patient per month (PPPM) costs for medical, pharmacy and total cost of care expenditures.

Changes in medical costs were not statistically different across drug groups in years 1 and 2. In contrast, the increase in pharmacy costs in the first year for GLP-1 RA was significantly higher than the other two drugs. Driven primarily by pharmacy costs, total cost of care trajectories showed similar between-drug differences.

Patients with type 2 diabetes initiating on a GLP-1 RA show significantly higher pharmacy cost patterns as compared to the DPP-4i and SGLT-2i groups; this higher pharmacy cost is not offset by reduced medical cost during the same period. Payers and providers should consider these cost patterns in both coverage and treatment decisions.