Comparison of GLP-1 analogues versus sitagliptin in the management of type 2 diabetes: systematic review and meta-analysis of head-to-head studies.

Author(s): Wang T(1), Gou Z(2), Wang F(3), Ma M(2), Zhai SD(4).

Affiliation(s): Author information: (1)Department of Pharmacy Administration and Clinical Pharmacy, Peking University Health Science Center, Beijing, China; Department of Pharmacy, Peking University Third Hospital, Beijing, China. (2)Department of Pharmacy, First Affiliated Hospital of Harbin Medical University, Harbin, China. (3)Department of Pharmacy Practice, School of Pharmacy, University of Connecticut, Storrs, Connecticut, United States of America. (4)Department of Pharmacy, Peking University Third Hospital, Beijing, China.

Publication date & source: 2014, PLoS One. , 9(8):e103798

BACKGROUND: Incretin-based therapies which include glucagon-like peptide-1 (GLP-1) receptor agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors are recommended by several practice guidelines as second-line agents for add-on therapy to metformin in patients with type 2 diabetes (T2DM) who do not achieve glycemic control with metformin plus lifestyle interventions alone. The purpose of this study is to perform a systematic review with meta-analysis of existing head to head studies to compare the efficacy and safety of GLP-1 analogues with DPP-4 inhibitors. METHODS: We performed a systematic review and meta-analysis of head-to-head studies to compare GLP-1 analogues with DPP-4 inhibitors in the management of type 2 diabetes. A random effects model was selected to perform the meta-analyses, results were expressed as weighted mean differences for continuous outcomes and relative risks for dichotomous outcomes, both with 95% confidence intervals, and with I2 values and P values as markers of heterogeneity. RESULTS: Four head-to-head randomized controlled studies with 1755 patients were included. Compared to sitagliptin, GLP-1 analogues are more effective in reducing HbA1C (weight mean difference -0.41%, 95% CI -0.51 to -0.31) and body weight (weight mean difference -1.55 kg, 95% CI -1.98 to -1.12). Conversely, GLP-1 analogues are associated with a higher incidence of gastrointestinal adverse events compared to sitagliptin: nausea (relative risk 3.14, 95% CI 2.15 to 4.59), vomiting (relative risk 2.60, 95% CI 1.48 to 4.56), diarrhea (relative risk 1.82, 95% CI 1.24 to 2.69), and constipation (relative risk 2.50, 95% CI 1.33 to 4.70). CONCLUSIONS: The result of this meta-analysis demonstrates that compared to sitagliptin, GLP-1 analogues are more effective for glycemic control and weight loss, but have similar efficacy in reducing blood pressure and lipid parameters, however, GLP-1 analogues are associated with a higher incidence of gastrointestinal adverse events and a similar incidence of hypoglycemia compared to sitagliptin.