# Efficacy and Safety of Tirzepatide in Japanese Participants With Obesity: A Subpopulation Analysis of the SURMOUNT‐1 Trial

## TL;DR

Tirzepatide significantly reduced body weight and improved health markers in Japanese adults with obesity compared to placebo over 72 weeks.

## Contribution

This study provides new evidence on the efficacy and safety of tirzepatide in Japanese individuals with obesity or overweight.

## Key findings

- Tirzepatide doses (5, 10, 15 mg) led to significant weight loss compared to placebo.
- 91.7% to 100% of participants achieved ≥5% weight reduction with tirzepatide.
- Improvements in cardiometabolic measures were observed with no new safety concerns.

## Abstract

This prespecified subpopulation analysis aimed to assess the efficacy and safety of once‐weekly tirzepatide versus placebo alongside lifestyle intervention in Japanese adults with obesity or overweight.

Data from 102 Japanese adults in the SURMOUNT‐1 trial with BMI ≥ 30 kg/m2 or ≥ 27 kg/m2 and ≥ 1 weight‐related comorbidity were analyzed. Coprimary endpoints were mean percent change in body weight and the proportion of participants who achieved ≥ 5% body weight reduction at week 72.

Participants in the tirzepatide 5‐, 10‐, and 15‐mg groups had a statistically significantly greater (all p < 0.001) least squares mean (standard error) percent change in body weight compared with those in the placebo group: −12.0% (1.7%), −22.4% (1.7%), −22.1% (1.6%), and −0.3% (1.6%), respectively. Overall, 91.7%, 100%, and 96.6% of participants in the tirzepatide 5‐, 10‐, and 15‐mg groups, respectively, had ≥ 5% weight reduction at week 72, compared with 15.4% in the placebo group. Significant improvements in cardiometabolic measures were also observed with tirzepatide at week 72 compared to placebo. No new safety concerns were identified.

Once‐weekly treatment with tirzepatide demonstrated significant reductions in body weight and prespecified cardiometabolic measures compared with placebo in Japanese adults with obesity or overweight.

ClinicalTrials.gov identifier: NCT04184622 https://clinicaltrials.gov/study/NCT04184622

What is already known?○The global, multicenter, phase 3 SURMOUNT‐1 trial demonstrated substantial and sustained body weight reductions in adults with obesity or overweight treated with once‐weekly tirzepatide (5, 10, or 15 mg) or placebo over 72 weeks.○Improvements in all prespecified cardiometabolic measures, including lipids, cholesterol, and systolic/diastolic blood pressure, were also observed with tirzepatide treatment.
What does this study add?○In this subpopulation analysis of Japanese adults with obesity or overweight from SURMOUNT‐1, treatment with tirzepatide (5, 10, or 15 mg) for 72 weeks resulted in significant reductions in body weight and prespecified cardiometabolic measures compared with placebo○All doses of tirzepatide were generally well tolerated, with no new safety concerns identified.
How might these results change the direction of research or the focus of clinical practice?○These findings add to the limited data on tirzepatide in Asian populations with obesity or overweight, including Japanese individuals, and are of clinical importance as Japanese individuals have a higher risk of obesity‐related health disorders at a lower BMI than Caucasians.○Considering the chronic nature of obesity and its related health issues, these findings support the longer‐term studies of tirzepatide in Japanese individuals with obesity or overweight.

What is already known?○The global, multicenter, phase 3 SURMOUNT‐1 trial demonstrated substantial and sustained body weight reductions in adults with obesity or overweight treated with once‐weekly tirzepatide (5, 10, or 15 mg) or placebo over 72 weeks.○Improvements in all prespecified cardiometabolic measures, including lipids, cholesterol, and systolic/diastolic blood pressure, were also observed with tirzepatide treatment.

The global, multicenter, phase 3 SURMOUNT‐1 trial demonstrated substantial and sustained body weight reductions in adults with obesity or overweight treated with once‐weekly tirzepatide (5, 10, or 15 mg) or placebo over 72 weeks.

Improvements in all prespecified cardiometabolic measures, including lipids, cholesterol, and systolic/diastolic blood pressure, were also observed with tirzepatide treatment.

What does this study add?○In this subpopulation analysis of Japanese adults with obesity or overweight from SURMOUNT‐1, treatment with tirzepatide (5, 10, or 15 mg) for 72 weeks resulted in significant reductions in body weight and prespecified cardiometabolic measures compared with placebo○All doses of tirzepatide were generally well tolerated, with no new safety concerns identified.

In this subpopulation analysis of Japanese adults with obesity or overweight from SURMOUNT‐1, treatment with tirzepatide (5, 10, or 15 mg) for 72 weeks resulted in significant reductions in body weight and prespecified cardiometabolic measures compared with placebo

All doses of tirzepatide were generally well tolerated, with no new safety concerns identified.

How might these results change the direction of research or the focus of clinical practice?○These findings add to the limited data on tirzepatide in Asian populations with obesity or overweight, including Japanese individuals, and are of clinical importance as Japanese individuals have a higher risk of obesity‐related health disorders at a lower BMI than Caucasians.○Considering the chronic nature of obesity and its related health issues, these findings support the longer‐term studies of tirzepatide in Japanese individuals with obesity or overweight.

These findings add to the limited data on tirzepatide in Asian populations with obesity or overweight, including Japanese individuals, and are of clinical importance as Japanese individuals have a higher risk of obesity‐related health disorders at a lower BMI than Caucasians.

Considering the chronic nature of obesity and its related health issues, these findings support the longer‐term studies of tirzepatide in Japanese individuals with obesity or overweight.