Efficacy and safety of tirzepatide in patients with type 2 diabetes: A systematic review and meta-analysis

Purpose: A systematic review and meta-analysis was conducted to combine the data available from clinical trials and evaluate the clinical efficacy and safety of tirzepatide in people with type 2 diabetes (T2D). Methods: We systematically searched the MEDLINE, Embase, Cochrane Library, and clinical trials registries (https://clinicaltrials.gov) up to 25 March 2022 for randomized controlled trials (RCTs) that compared tirzepatide with placebo or active hypoglycemic drugs in subjects with T2D. Heterogeneity was judged by the I (2) value and Cochran’s Q test. The randomized effects model was adopted to calculate risk ratios and weighted mean differences (WMDs). The primary outcome was the change from baseline in HbA1c levels. Secondary efficacy endpoints were fasting serum glucose (FSG), change of body weight, blood pressure, fasting lipid profiles, and safety indexes. Results: Six trials comprising 6,579 subjects (4,410 in the tirzepatide group and 2,054 in the control group) fulfilled the pre-specified criteria and were included in the study. Tirzepatide treatment resulted in reducing HbA1c (WMD: -1.07%; 95% confidence intervals [CIs]: −1.44, −0.56), FSG (WMD, −21.50 mg/dl; 95% CI: −34.44, −8.56), body weight (WMD: −7.99 kg; 95% CI −11.36, −4.62), and blood pressure and ameliorated fasting lipid profiles, without increasing hypoglycemia, either as monotherapy or an add-on therapy. Tirzepatide increased the risk of gastrointestinal adverse events mainly in add-on therapy but not in terms of pancreatitis or cholelithiasis. Furthermore, tirzepatide presented a dose–response effect on the reduction in HbA1c and body weight and increase in nausea and vomiting. Conclusion: In patients with type 2 diabetes, tirzepatide shows superior blood glucose control and weight loss performance, without an increased risk of hypoglycemia. Systematic Review Registration: (https://www.crd.york.ac.uk/PROSPERO), identifier (CRD42022319442).