Tirzepatide significantly improves glycemic control and body weight in real-world Japanese T2DM patients

Managing Type 2 Diabetes Mellitus (T2DM) effectively requires therapies that not only control blood glucose but also address associated metabolic factors like obesity. While dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonists like tirzepatide have shown remarkable efficacy in controlled clinical trials, real-world evidence, particularly in specific populations such as Japanese patients, remains limited. This gap in data makes it challenging to understand how these agents perform in routine clinical practice, where patient demographics and treatment adherence can vary significantly from trial settings. This study aimed to bridge that gap by evaluating tirzepatide's effectiveness in a diverse Japanese T2DM cohort.

This multicenter, retrospective, observational study included 324 Japanese patients with T2DM from seven institutions who received tirzepatide treatment for at least 24 weeks. The study evaluated effectiveness by comparing clinical and biochemical parameters before and after treatment. Various doses of tirzepatide were administered, with 42 (13.0%) patients on 2.5 mg, 211 (65.1%) on 5 mg, 35 (10.8%) on 7.5 mg, 25 (7.7%) on 10 mg, and 11 (3.4%) on 12.5 mg/15 mg. Primary endpoints included changes in glycated hemoglobin (HbA1c), plasma glucose, body weight, blood pressure, lipid profiles, liver enzyme levels, and renal function.

After 24 weeks of tirzepatide treatment, significant improvements were observed across key metabolic parameters. The median HbA1c level decreased from 7.9% [7.2-8.6] to 6.8% [6.1-7.5]. Similarly, median body weight reduced from 82.5 kg [73.5-94.6] to 80.0 kg [70.9-92.5]. The median changes from baseline to week 24 were -0.9% [-1.6 to -0.3] for HbA1c and -2.0 kg [-4.0 to 0.0] for body weight, both achieving high statistical significance (p < 0.001). Notably, the HbA1c reduction was more pronounced in patients who were GLP-1 receptor agonist-naïve (p < 0.001). Changes in HbA1c levels significantly correlated with baseline HbA1c levels (rs = -0.473, p < 0.001), but not with baseline BMI. These findings confirm the real-world efficacy of tirzepatide in a Japanese population.

Tirzepatide treatment led to a median 0.9% reduction in HbA1c and a 2.0 kg reduction in body weight over 24 weeks (p < 0.001 for both).