Costs and Consequences Associated With Newer Medications for Glycemic Control in Type 2 Diabetes

OBJECTIVE

Newer medications offer more options for glycemic control in type 2 diabetes. However, they come at considerable costs. We undertook a health economic analysis to better understand the value of adding two newer medications (exenatide and sitagliptin) as second-line therapy to glycemic control strategies for patients with new-onset diabetes.

RESEARCH DESIGN AND METHODS

We performed a cost-effectiveness analysis for the U.S. population aged 25–64. A lifetime analytic horizon and health care system perspective were used. Costs and quality-adjusted life years (QALYs) were discounted at 3% annually, and costs are presented in 2008 U.S. dollars. We compared three glycemic control strategies: 1) glyburide as a second-line agent, 2) exenatide as a second-line agent, and 3) sitagliptin as a second-line agent. Outcome measures included QALYs gained, incremental costs, and the incremental cost-effectiveness ratio associated with each strategy.

RESULTS

Exenatide and sitagliptin conferred 0.09 and 0.12 additional QALYs, respectively, relative to glyburide as second-line therapy. In base case analysis, exenatide was dominated (cost more and provided fewer QALYs than the next most expensive option), and sitagliptin was associated with an incremental cost-effectiveness ratio of $169,572 per QALY saved. Results were sensitive to assumptions regarding medication costs, side effect duration, and side effect–associated disutilities.

CONCLUSIONS

Exenatide and sitagliptin may confer substantial costs to health care systems. Demonstrated gains in quality and/or quantity of life are necessary for these agents to provide economic value to patients and health care systems.Diabetes is increasingly endemic in the U.S. In 2007, 23.5 million Americans aged >20 years had diabetes compared with 18.0 million in 2002 (1). Diabetes was the seventh leading cause of death in 2006 (1). It remains the leading cause of blindness, end-stage renal disease, and nontraumatic amputations. A total of $116 billion in direct health care costs are attributable to diabetes annually (2).Large clinical trials from the U.S. and Europe have demonstrated that tighter glycemic control can prevent diabetes complications in individuals with recent-onset disease (3,4); in older individuals with longer disease duration, recent studies have found no cardiovascular benefit of tight control (5) and possible harm (6). In the past several years, the U.S. Food and Drug Administration (FDA) approved nine new products for glycemic control (7). Some are new forms or combinations of existing classes, whereas others belong to new therapeutic classes such as amylin analogs, glucagon-like peptide-1 receptor agonists, incretins, and dipeptidyl peptidase-IV inhibitors.Although these agents increase the management options available, they come at increased costs (8). Previous analyses of the health economics of glycemic control were published before the FDA approval of many new agents (9–11). Recent studies have examined the cost-effectiveness of exenatide or sitagliptin in European populations, reflecting costs and management appropriate for the modeled populations but not necessarily reflective of the U.S. (12–14).In this analysis, we estimate the costs associated with two of the most prescribed examples of these new medications: exenatide and sitagliptin. We project the gains in health outcomes necessary to have these newer medications pose good economic value for patients with new-onset diabetes, using the incremental cost-effectiveness ratio as our metric.