Semaglutide 2.4 mg produced 9-16% weight loss across all demographic subgroups in Japanese and Korean adults, with sex, diabetes status, and cholesterol problems significantly influencing how much weight was lost.
-9.4% to -16.4%Weight loss range across all subgroups with semaglutide 2.4 mg over 68 weeks in Japanese and Korean adults
What the researchers found
In the STEP 6 trial subgroup analysis, semaglutide 2.4 mg produced clinically meaningful weight loss across all demographic subgroups in a Japanese and Korean population, with estimated mean weight changes ranging from -9.40% to -16.42% over 68 weeks. Both semaglutide doses outperformed placebo.
Notably, sex significantly affected the response — the treatment-by-sex interaction was highly significant for both doses (p=0.0008 and p=0.0005). Having type 2 diabetes or dyslipidemia at baseline also significantly modified the response to the higher 2.4 mg dose. Despite these variations, semaglutide worked across all subgroups examined.
Why it matters
Most major semaglutide weight loss trials (STEP 1-5) were conducted primarily in Western populations. East Asian populations tend to develop obesity-related diseases at lower BMIs and have different body composition patterns. This analysis confirms semaglutide is effective across East Asian demographic subgroups, supporting its use in these populations while highlighting that sex, diabetes status, and dyslipidemia may influence how much weight individual patients lose.
The numbers in context
n=401 · 148 female, 253 male · Weight loss: -9.40% to -16.42% (semaglutide 2.4 mg) · 68 weeks · Sex interaction p=0.0005 · T2D interaction p=0.0381 · Dyslipidemia interaction p=0.0181
How the study worked
Post-hoc subgroup analysis of the STEP 6 randomized controlled trial. Japanese and Korean adults with overweight or obesity received subcutaneous semaglutide 2.4 mg, semaglutide 1.7 mg, or placebo for 68 weeks. Weight change was analyzed by subgroups including baseline weight, BMI, age, sex, glycemic status, dyslipidemia, and hypertension. Treatment-by-subgroup interactions were tested statistically.
Who was studied
401 Japanese and Korean adults with overweight or obesity (including a subset with type 2 diabetes), 148 female and 253 male
What this study cannot tell us
This is a post-hoc subgroup analysis, meaning the subgroup comparisons were not the primary study objective and may be underpowered. The study included only Japanese and Korean participants, so results may not generalize to all East Asian populations. With 401 total participants split across three arms and multiple subgroups, some subgroup sizes were relatively small.
How to read the evidence
Strong evidence — this is a subgroup analysis from a well-designed randomized controlled trial (STEP 6) published in a peer-reviewed journal. While post-hoc subgroup analyses have inherent limitations, the parent trial was double-blind and placebo-controlled.
When this study was published
Published in 2024 based on the STEP 6 trial data. Highly relevant as semaglutide continues to be adopted globally and East Asian-specific data is increasingly needed for clinical decision-making.
The bigger picture
As GLP-1 drugs expand globally, understanding how they perform in different ethnic populations is crucial. East Asian patients often develop metabolic disease at lower BMIs than Western patients, and drug metabolism can differ across populations. This study adds important evidence that semaglutide is effective in this population while identifying patient characteristics that predict better or worse responses — information that could help clinicians set expectations and personalize treatment.
Questions still open
- Why does sex significantly modify the weight loss response to semaglutide in East Asian populations?
- Do East Asian patients with type 2 diabetes lose less weight on semaglutide than those without, and if so, why?
- How do these East Asian results compare to subgroup analyses from the primarily Western STEP 1-4 trials?
Common questions
Does semaglutide work differently in East Asian patients?
Why does sex affect how much weight people lose on semaglutide?
Read the original research
Clinical characteristics affecting weight loss in an East Asian population receiving semaglutide: A STEP 6 subgroup analysis.
Obesity research & clinical practice, 18(6), 457-464
Citation
Kadowaki, Takashi; Lee, Sang Yeoup; Ogawa, Wataru; Nishida, Tomoyuki; Overvad, Maria; Tobe, Kazuyuki; Yamauchi, Toshimasa; Lim, Soo. (2024). Clinical characteristics affecting weight loss in an East Asian population receiving semaglutide: A STEP 6 subgroup analysis.. Obesity research & clinical practice, 18(6), 457-464. https://doi.org/10.1016/j.orcp.2025.01.002