Abstract
INTRODUCTION: Treatment with glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors, which target the incretin axis, has the potential to improve glycemic control in type 2 diabetes patients without the weight gain associated with traditional therapies. To evaluate the relative cost-effectiveness of incretin therapies, the present study aimed to compare the long-term clinical and cost implications associated with liraglutide and sitagliptin in type 2 diabetes patients in Spain. METHODS: Data were taken from a randomized, controlled trial (NCT00700817) in which adults with type 2 diabetes failing metformin monotherapy were randomly allocated to receive either liraglutide 1.2 mg or sitagliptin 100 mg daily in addition to metformin. Long-term projections of clinical outcomes and direct costs (2012 EUR) based on observed treatment effects were made using a published and validated type 2 diabetes model. Costs were taken from published sources. Future costs and clinical benefits were discounted at 3% annually. Sensitivity analyses were performed. RESULTS: Liraglutide was associated with improved discounted life expectancy (14.05 versus 13.91 years) and quality-adjusted life expectancy [9.04 versus 8.87 quality-adjusted life years (QALYs)] compared to sitagliptin. Improved clinical outcomes were driven by improved glycemic control, leading to reduced incidence of diabetes-related complications, including renal disease, cardiovascular disease, ophthalmic and diabetic foot complications. Liraglutide was associated with increased direct costs of EUR 2,297, yielding an incremental cost-effectiveness ratio of EUR 13,266 per QALY gained versus sitagliptin. CONCLUSIONS: Liraglutide was projected to improve life expectancy, quality-adjusted life expectancy and reduce incidence of diabetes-related complication. Liraglutide is likely to be cost-effective versus sitagliptin from a healthcare payer perspective in Spain.