P1608 - Demographic and Regional Disparities in GLP-1 Receptor Agonist Clinical Trials for Weight Loss: A Comparative Meta-Analysis of US and International RCTs

Kimberly Ho, MD¹, Taranika Sarkar Das, MD², Joao Monteiro, PhD³, Sonali Paul, MD, MS, FACG⁴, Paige McLean Diaz, MD⁵
1Brown University, Little Neck, NY; 2The Brooklyn Hospital Center, Brooklyn, NY; 3Brown University, Providence, RI; 4University of Chicago, Chicago, IL; 5Brown Medicine/Brown University Health, Riverside, RI

Introduction: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) treat obesity, which disproportionately affects racial/ethnic minorities, including 20% of Black adults, 18% Hispanic, and 19% American Native/Indian compared to 16% White adults and 7% Asian Americans in the US (NIH). We conducted a meta-analysis (MA) to assess demographic and regional representation in GLP-1 RA weight-loss randomized controlled trials (RCTs) because we suspect that GLP-1 RA trial generalizability may be limited by relative underrepresentation of key affected patient populations.

Methods: We reviewed 149 English-language RCTs that looked at GLP-1 RAs for weight loss from 2015 to 2025. Random-effects MA assessed demographic and clinical differences in US vs international trials using RRs.

Results: 61 RCTs met inclusion criteria for MA (n=59,425, 45 US, 16 international) (Figure 1). Mean age was 54.7±6.7 years and most were female (95% CI: 46–54%, I² = 98.8%). Whites comprised 69% overall (I² = 99.91%), including 75% in US RCTs and 47% in international RCTs. US RCTs were 4 times more likely to include Whites (4.10 [4.05-4.16]). Hispanic or Latinos made up 24% (I² = 99.84%), with 27% in US vs 11% internationally (RR 1.93 [1.85–2.01]). Blacks were 6% overall (I² = 99.14%), with 6% in US and 7% internationally. US RCTs were 15% less likely to include Blacks (RR 0.85 [0.74-0.97]). Overall, 19% were Asian (I² = 99.97%), with 11% in the US and 42% internationally. RCTs conducted internationally were 7 times more likely to include Asians than those conducted in the US (RR 6.92 [6.86-6.98]). American Indians/Natives (AI/AN) accounted for 2% (I² = 99.91%), with 3% in the US and 1% internationally. RCTS conducted in the US were 15% more likely to include AI/AN (1.15 [0.94-1.36]).

Blacks (6% in this MA vs 20% of US obesity), Hispanic (27% vs 31%), and AI/AN (3% vs 19%) patients were more underrepresented than the overall US obesity prevalence (NIH). Non-Hispanic whites (75% in this MA vs 17% of US obesity) were overrepresented in our study. Asian Americans were properly represented. (Figure 2).

Discussion: These findings reveal substantial underrepresentation of Black, Hispanic, and AI/AN in GLP-1 RA RCTs, especially in the US despite bearing a higher obesity burden. These disparities raise critical concerns about the external validity of GLP-1 RCTs. Inclusive and representative trial enrollment is essential to address existing health disparities across global populations and advance health equity.


Figure: Figure 1. PRISMA flow chart.


Figure: Demographic data reported in US and international GLP-1 RA clinical trials.

Disclosures:
Kimberly Ho indicated no relevant financial relationships.
Taranika Sarkar Das indicated no relevant financial relationships.
Joao Monteiro indicated no relevant financial relationships.
Sonali Paul: Eli Lilly – Stock-publicly held company(excluding mutual/index funds).
Paige McLean Diaz indicated no relevant financial relationships.

Kimberly Ho, MD¹, Taranika Sarkar Das, MD², Joao Monteiro, PhD³, Sonali Paul, MD, MS, FACG⁴, Paige McLean Diaz, MD⁵. P1608 - Demographic and Regional Disparities in GLP-1 Receptor Agonist Clinical Trials for Weight Loss: A Comparative Meta-Analysis of US and International RCTs, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.