Geographic and demographic disparities in chronic spontaneous urticaria clinical trials

Summary: Abstract Body: Chronic spontaneous urticaria (CSU) affects populations worldwide, with particularly high prevalence in Asian and Latin American populations. Although therapeutic options are expanding, limited data exists on the diversity of populations in clinical trials. While the underrepresentation of racial and ethnic minorities in dermatology clinical trials is well-recognized, trends in CSU trials remain unexplored. This study evaluates the geographic diversity, enrollment, and the inclusion of racial and ethnic data in phase II and III randomized control trials (RCTs) for CSU. CSU RCTs conducted between January 2000 and November 2024 were identified through ClinicalTrials.gov. Race and ethnicity data were extracted for each RCT. A total of 42 trials comprising of 10,012 participants met inclusion criteria. Most trials (n=32, 76.19%) were conducted within the last decade, with Germany being the most common trial location (n=21, 50.0%), followed by the United States (n=17, 12.5%), Spain (n=15, 35.71%), Canada (n=13, 30.95%), and Japan (n=12, 28.57%). Of the 42 trials included in the analysis, only 27 (74%) did not include race and/or ethnicity data. Of the 10,012 total participants, 55.34% (5,541) were unknown or not reported, 28.06% (2,810) were White, 0.94% (98) were Black/African American, 10.22% (1024) were Asian, .43% (44) were more than one race, 0.69% (70) were American Indian/Alaska Native, and 0.02% (3) were Native Hawaiian/Pacific Islander. Furthermore, only 0.54% (54) were reported as Hispanic or Latino. These findings highlight the urgent need to improve the racial/ethnic and geographic diversity in RCTs for CSU. There is a significant gap in demographic reporting with only a third of trials documenting demographic information. Future trials should expand to underrepresented regions, improve patient diversity, and prioritize the standardized reporting of race and ethnicity data to ensure equitable treatment outcomes and better represent the global burden of CSU. Aditya Joshi¹, Lauren Gawey¹, Khiem Tran¹, Jennifer Hsiao², Vivian Y. Shi¹ 1. Dermatology, University of Washington, Seattle, WA, United States. 2. Dermatology, University of Southern California, Los Angeles, CA, United States. Minoritized Populations and Health Disparities Research