A Review: Comparison of Efficacy of Liraglutide Versus Sitagliptin add-on-to Metformin in Type 2 Diabetes Mellitus patients

Background: The aim of this review is to compare the efficacy of liraglutide versus sitagliptin add-on-to metformin in patients with Type 2 Diabetes Mellitus and inadequate glycemic control for rational use of drugs. Methods: We searched for randomized controlled trials (RCT) in MEDLINE, Web of science, PubMed, Cochrane library, CNKI, and Wanfang database and extracted data from all randomized controlled trials (RCTs) up to July 11, 2019 of liraglutide versus sitagliptin given in combination with metformin. RCTs were selected only if they were RCTs comparing DPP-4 inhibitor (sitagliptin) monotherapy to metformin monotherapy with the GLP-1 Receptor Agonists (liraglutide), duration of treatment was ≥26 weeks and reported data on hemoglobin A1c (HbA1c) change, fasting plasma glucose (FPG) change, Odds ratio (OR), mean difference (MD), 95% confidence interval are used to analyze the outcomes. Results: A total of 2,257 patients from 6 RCTs were included in the study. When compared with sitagliptin (100mg) in combination with metformin group, the group of patients treated with liraglutide1.2mg and 1.8mg and metformin, produced greater reduction in HbA1c, FBG. (95% CI). The group of patients with 1.8mg liraglutide had significant weight loss. The incidence of nausea, hypoglycemic episodes, gastrointestinal problems was higher than the sitagliptin with metformin groups. Conclusions: The results of this study indicated that the liraglutide – metformin combination therapy could significantly lower the HbA1c level and increased reduction of body weight. ADRs such as gastrointestinal problems, hypoglycemic episodes were common in liraglutide treatment group.