Efficacy and Safety of Dulaglutide Compared to Liraglutide: A Systematic Review and Meta-analysis in Patients with Type 2 Diabetes Mellitus

Diabetes mellitus has been always one of the most prevalent chronic diseases in the last decades. There exist a wide range of pharmacological agents for controlling this disease. However, these agents fare differently in terms of efficacy and safety. Hence, the aim of this study was to compare dulaglutide and liraglutide, two glucagon-like peptide-1 receptor agonists, in terms of efficacy and safety, drawing on a systematic review and meta-analysis. A systematic review and meta-analysis were carried out in January 2018. The articles were evaluated by two independent investigators and their quality was evaluated using Jadad scale and the Cochrane Collaboration's tools. Finally, the eligible articles entered the study. HbA1c and FBS were considered as efficacy outcomes. Safety profile was evaluated based on several outcomes such as serious side effects and vital signs. Three articles met the inclusion and exclusion criteria. The results indicated that the mean difference (MD) of HbA1c reduction was -0.10% (95% CI, -0.20% to -0.01%, P=0.03) in the patients who received dulaglutide in comparison with the patients who received liraglutide. In addition, dulaglutide was safer than liraglutide in terms of gastrointestinal problems (RR=0.85, 95% CI, 0.73 to 0.99, P=0.04, I-2=55%) and heart rate (RR=-1.14, 95% CI, -1.90 to -0.38, P=0.003, I-2=0%). Once-weekly dulaglutide showed a further reduction in HbA1c compared to once-daily liraglutide. However, comparisons between these regimens indicated no significant difference between groups in either FBS reduction or safety profile. Similarly, no statistically significant difference was observed in treatment discontinuation, hypoglycemia events, and vital signs.