Is tirzepatide 15 mg the preferred treatment strategy for type 2 diabetes? A meta-analysis and trial-sequence-analysis.

OBJECTIVE: The study aims to evaluate tirzepatide's efficacy and safety in treating type 2 diabetes by meta-analysis and trial-sequential-analysis (TSA). MATERIALS AND METHODS: Eight databases were searched for clinical trials on tirzepatide for type 2 diabetes with a time limit of November 2022. Revman5.3 and TSA 0.9.5.10 Beta were selected for meta-analysis and TSA. RESULTS: Compared with placebo, the meta-analysis demonstrated that tirzepatide 15 mg reduced hemoglobin-type-A1C (HbA1c) (p<0.00001), fasting-serum-glucose (FSG) (p<0.00001), and weight (p<0.00001). Compared with insulin, tirzepatide 15 mg reduced HbA1c (p<0.00001), FSG (p<0.00007), and weight (p<0.00001). Compared with glucagon-like-peptide-1 receptor-agonist (GLP-1 RA), tirzepatide 15 mg reduced HbA1c (p=0.00004), FSG (p=0.001), and weight (p<0.00001). In safety endpoints, the meta-analysis revealed that adverse events (AEs) of placebo, insulin and GLP-1 RA were comparable to tirzepatide 15 mg. The total AEs (p=0.02) and gastrointestinal (GI) AEs (p=0.03) were higher in tirzepatide 15 mg than in the placebo, while hypoglycemia (<54 mg/dl) was comparable. The major adverse cardiovascular events-4 (MACE-4) (p=0.03) and hypoglycemia (<54 mg/dl) (p<0.00001) of tirzepatide 15 mg were lower when compared to insulin, while total AEs (p=0.03) were increased. Compared with GLP-1 RA, tirzepatide 15 mg was comparable in safety endpoints in total AEs and GI AEs, while hypoglycemia (<54 mg/dl) (p=0.04) was higher. TSA indicated that HgA1c, FSG, and weight benefits were conclusive. In safety endpoints, only MACE-4 and hypoglycemia (<54 mg/dl) of Tirzepatide 15 mg vs. Insulin were conclusive. Harbord regression of AEs suggested no evident publication bias (p=0.618). CONCLUSIONS: Tirzepatide 15 mg reduced HbA1c and weight more effectively than placebo, insulin, and GLP-1 RA. Total AEs were higher than placebo and insulin but comparable to GLP-1 RA. Tirzepatide 15 mg is a kind of optimal strategy to treat type 2 diabetes. However, there is a need to focus on GI AEs.