Zero Dollar Copay Pharmacy Benefit Decreases Healthcare Expenditures Among Members With Type 2 Diabetes of Blue Cross Blue Shield of Louisiana.

Objectives: Blue Cross Blue Shield of Louisiana implemented the Zero Dollar Co-payment (ZDC) program on July 1, 2020. This study aims to evaluate whether the ZDC program can reduce total healthcare expenditures.

Methods: Blue Cross Blue Shield of Louisiana's medical and pharmacy claims from January 2019 to December 2021 was used in this study, and the index date was July 1, 2020. We identified 7603 continuously enrolled members with type 2 diabetes, including 3045 ZDC-eligible members as the ZDC group and 4558 Administrative Service Only group members as the control group. The primary outcome measure was monthly total healthcare expenditure, which included monthly medical and pharmacy spending. ZDC program's effectiveness was evaluated by a 2-way fixed-effect difference-in-difference regression weighted by odds of propensity scores. The study population was further classified into 3 subgroups based on their baseline use of ZDC-eligible antidiabetic medications: pre-ZDC users, pre-ZDC nonusers, and complex users.

Results: The ZDC pharmacy benefit was associated with a significant reduction in total healthcare spending of $-121.76 per member per month (PMPM) (P = .002) and medical spending of $-131.50 PMPM (P < .001). For complex users, the ZDC program was associated with reductions of $283.44 PMPM (P = .006) in total healthcare spending and $385.45 PMPM (P < .001) in medical spending, whereas pharmacy spending significantly increased by $102.01 PMPM (P = .022). No significant results were observed for pre-ZDC users and pre-ZDC nonusers.

Conclusions: The ZDC program was effective in reducing total healthcare expenditures among ZDC-eligible members with type 2 diabetes in Louisiana.