Sinha A (Center for Healthcare Knowledge Management, VA New Jersey), Rajan M
(Center for Healthcare Knowledge Management, VA New Jersey), Shen C
(Center for Healthcare Knowledge Management, VA New Jersey), Aron D
(Cleveland VAMC ), Hoerger T
(Health, Social, and Economics Research, RTI, Research Triangle Park, NC), Pogach L
(Center for Healthcare Knowledge Management, VA New Jersey)
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 of these medications (exenatide and sitagliptin) as second-line therapy to existing glycemic control strategies.
We performed both cost minimization and cost-effectiveness analysis using a Markov cohort model developed at the CDC. We compared three strategies to prevent diabetic complications in the U.S. general population through glycemic control: 1) using generic drugs only, 2) using exenatide as a second-line agent, and 3) using sitagliptin as a second-line agent. The model incorporated rates of glycemic change before and after therapy, hazards of diabetic complications as a function of glycemic control, and rates of transition among hypoglycemic agents. With a healthcare system perspective and lifetime horizon, treatment costs were derived from literature review; manufacturers’ wholesale prices were used for drug costs. Costs and quality-adjusted life years (QALYs) were discounted at 3% annually; inflation adjustment to 2008 dollars was performed.
Assuming metformin +/- exenatide +/- thiazolidinedione +/- NPH insulin and metformin +/- sitagliptin +/- thiazolidinedione +/- NPH insulin provide the same degree of glycemic control as a generic drug strategy of metformin +/- sulfonylurea +/- thiazolidinedione +/- NPH insulin, then strategies incorporating exenatide and sitagliptin are associated with $17,529 and $14,650 more per treated patient than the generic drug strategy. Assuming a cost-effectiveness threshold of 1 to 3 times per capita GDP ($44,000 to $132,000 per QALY), exenatide would need to provide an additional 0.14 to 0.40 QALYs over a patient’s lifetime in order for exenatide to meet cost-effectiveness criteria. Similarly, sitagliptin would need to provide an additional 0.11 to 0.33 QALYs per patient to meet these criteria. Such QALY gains would need to be realized by decreases in risk of death or increases in preference-weighted quality of life.
Exenatide and sitagliptin confer substantial costs to healthcare systems and require QALY gains to offer economic value.
Demonstrated gains in quality and/or quantity of life are necessary for these agents to provide economic value to patients, healthcare systems, and payors.