RCT: Tirzepatide Significantly Reduces Weight and Diabetes Risk in Obese Adults with Prediabetes
15 Nov, 2024 | 13:29h | UTCBackground: Obesity is a chronic disease that significantly increases the risk of type 2 diabetes, particularly in individuals with prediabetes. Weight reduction has been shown to improve insulin sensitivity and beta-cell function, potentially delaying or preventing the onset of type 2 diabetes. Tirzepatide, a dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist, has demonstrated significant weight loss and glycemic control in short-term studies.
Objective: To evaluate the long-term efficacy and safety of tirzepatide in reducing body weight and delaying progression to type 2 diabetes in obese adults with prediabetes over a period of three years.
Methods: In this phase 3, double-blind, randomized, controlled trial (SURMOUNT-1), 1032 obese adults with prediabetes were randomized 1:1:1:1 to receive once-weekly subcutaneous tirzepatide (5 mg, 10 mg, or 15 mg) or placebo, alongside lifestyle intervention, for 176 weeks, followed by a 17-week off-treatment period. The primary endpoints included percent change in body weight and onset of type 2 diabetes during the treatment and follow-up periods.
Results: At week 176, participants receiving tirzepatide achieved significant mean weight reductions of –12.3% (5 mg), –18.7% (10 mg), and –19.7% (15 mg), compared to –1.3% with placebo (P<0.001 for all comparisons). Progression to type 2 diabetes was significantly lower in the tirzepatide groups (1.3%) compared to placebo (13.3%), with a hazard ratio of 0.07 (95% CI, 0.0 to 0.1; P<0.001). After the 17-week off-treatment period, 2.4% of tirzepatide-treated participants and 13.7% of placebo-treated participants had developed type 2 diabetes (hazard ratio, 0.12; 95% CI, 0.1 to 0.2; P<0.001). Common adverse events were gastrointestinal and generally mild to moderate.
Conclusions: Three years of tirzepatide treatment in obese adults with prediabetes resulted in substantial and sustained weight loss and significantly reduced the risk of progression to type 2 diabetes compared to placebo, with an acceptable safety profile.
Implications for Practice: Tirzepatide may be an effective long-term therapeutic option for weight management and diabetes prevention in obese patients with prediabetes, potentially altering clinical approaches to obesity and metabolic disease management.
Study Strengths and Limitations: Strengths include the long duration of the trial and large sample size, providing robust data on long-term efficacy and safety. Limitations involve participant attrition and higher withdrawal rates, especially in the placebo group, which may affect the generalizability of the findings.
Future Research: Further studies are needed to explore the mechanisms of tirzepatide’s effects on beta-cell function and insulin sensitivity, as well as its impact on cardiovascular outcomes and quality of life in diverse populations.