Sulfonylurea as second-line therapy appeared to lower cost in a population-based model

Sulfonylurea as second-line therapy for glycemic control in type 2 diabetes appeared to yield similar outcomes and quality-adjusted life-years (QALYs) but led to lower costs and longer time to insulin dependence compared with a dipeptidyl peptidase-4 (DPP-4) inhibitor, glucagon-like peptide-1 (GLP-1) receptor agonist, and insulin, according to a recent study.

Researchers used a population-based glycemic control Markov model to simulate natural variation in HbA1c progression. A U.S. data set of type 2 diabetes patients who were privately insured was used for calibration. Treatment intensification of metformin monotherapy with a sulfonylurea, a DPP-4 inhibitor, a GLP-1 receptor agonist, and insulin was compared, with the goals of addressing the benefits and harms of each regimen. In those treated with a sulfonylurea, a DPP-4 inhibitor, or a GLP-1 receptor agonist, the second-line drug was started if and when the goal HbA1c was exceeded; insulin was started as a third-line agent in place of the second-line agent if and when the goal HbA1c was exceeded again. In those treated with insulin as second-line therapy, the drug was started as soon as the goal HbA1c was exceeded. None of the regimens were changed after initiation of insulin.

The study's outcome measures were life-years, QALYs, mean time to insulin dependence, and expected medication cost per QALY from diagnosis to first diabetes-related complication or death. Results were published online Feb. 26 by Diabetes Care.

In the model, life-years and QALYs were similar for all regimens at all glycemic control goals. However, second-line therapy with a sulfonylurea led to significantly lower costs per QALY. Compared with sulfonylurea in the base-case analysis, a DPP-4 inhibitor, a GLP-1 agonist, and insulin as second-line agents were associated with mean additional medication costs in women and men of $141 and $160 per QALY, $191 and $216 per QALY, and $150 and $170 per QALY, respectively. The mean time from diabetes diagnosis to insulin initiation in men and women was 2.76 years and 2.59 years in those whose second-line agent was a sulfonylurea, 2.33 years and 2.13 years in those whose second-line agent was a DPP-4 inhibitor, 2.40 years and 2.21 years in those whose second-line agent was a GLP-1 agonist, and 1.72 years and 1.59 years in those whose second-line agent was insulin, respectively. For all regimens, a HbA1c goal of 7% resulted in higher QALYs than a goal of 8%.

The authors cautioned that their results are from a model and do not necessarily reflect what would occur in clinical practice. In addition, they used data from privately insured patients and the study model assumed that HbA1c values varied not continuously but among discrete states and at discrete time intervals. However, the authors concluded that a sulfonylurea as second-line therapy for type 2 diabetes was comparable to other second-line therapies in glycemic control and QALYs but appeared to cost less at all HbA1c goals ranging from 6.5% to 8%. “Our model can serve as an adjunctive decision aid to facilitate treatment selection for people newly diagnosed with type 2 diabetes in a way that trades off health and economic implications for patients,” the authors wrote. “It can also be used by health care providers and payers to determine whether a particular treatment option is consistent with the goal of high-value care.”