Cost Effectiveness of DPP-4i and SGLT2i Combination Therapy for the Treatment of Type 2 Diabetes in the U.S.

Management of type 2 diabetes (T2D) needs different treatment strategies to achieve the individualized glycemic goal. This study evaluated the long-term cost effectiveness of strategies involving pathway 1: metformin followed by intensification with dipeptidyl peptidase-4 inhibitors (DPP-4i), sodium-glucose co-transporter 2 inhibitors (SGLT2i) and insulin vs. pathway 2: metformin followed by intensification with sulfonylurea (SU) and insulin in the U.S. Cost-effectiveness analysis was performed using the validated QuintilesIMS CORE Diabetes Model from a U.S. payer perspective. Clinical and economic outcomes were modeled over a lifetime for a cohort of T2D patients who fail to achieve glycemic goal on metformin monotherapy. Clinical data were obtained from clinical trials. Direct medical costs [e.g., medications (whole sale acquisition costs), diabetes management, adverse events, and complications] were obtained from published sources. Despite higher direct medical costs for pathway 1 compared to pathway 2 ($117,779 vs. $93,196 respectively); pathway 1 improved total quality-adjusted life years (QALY) by 0.28 vs. pathway 2. Pathway 1 also led to cost offsets from fewer diabetes-related complications and delayed initiation of insulin. The incremental cost-effectiveness ratio (ICER) was favorable for pathway 1 at $89,038/QALY. Most of the scenario analysis (changes in treatment effect, hypoglycemia, and cardiovascular protective effects of SGLT2is) resulted in ICERs under $100,000/QALY except for the population with baseline HbA1c of 7%, and older age (65+ years). Negotiated discounts on branded medications resulted in significant improvement in ICERs (ICER of $69,554/QALY for 15% discount and $0/QALY for 75% discount). Among patients failing metformin monotherapy in the U.S, additional intensification with DPP-4i followed by SGLT2i may be considered more cost effective compared to intensification with SU followed by insulin.