Dr Barragan-Carrillo on Global Disparities in Clinical Trial Availability in RCC

"A logical question to ask ourselves is: Why would we care? If you’re not facing a problem, it’s hard to understand. [However, beyond] social justice and trying to reach equity for all patients, even from a biological standpoint, when we achieve [better outcomes] in trials in populations that look like the real-world population, the evidence is much stronger."

Regina Barragan-Carrillo, MD, a postdoctoral research fellow at City of Hope Comprehensive Cancer Center, discusses disparities in the availability and characteristics of renal cell carcinoma (RCC) clinical trials in lower-income countries, as well as the importance of expanding clinical trial access and data sharing to underserved regions through international collaboration, government engagement, and decentralized trials.

Findings from an assessment of the proportion of RCC clinical trials conducted across countries with varying income levels were presented at the 2025 Genitourinary Cancers Symposium, Barragan-Carrillo begins. Among 178 countries, RCC clinical trials were available in 60.0% of high-income countries, 23.9% of upper-middle–income countries, and 7.7% of lower-middle–income countries. No RCC clinical trials were found in low-income countries during the 5-year study period, despite the large patient populations in these regions, she notes. Moreover, the odds of having access to RCC clinical trials were significantly lower in upper-middle–income, lower-middle–income, and low-income countries compared with high-income countries, with odds ratios (ORs) of 0.215 (95% CI, 0.114-0.404; P< .001), 0.056 (95% CI, 0.018-0.176; P < .001), and 0.013 (95% CI, 0.001-0.228; P= .003), respectively. This is particularly concerning given that a significant proportion of new cancer cases are diagnosed in low- and middle-income countries, meaning a large number of patients in these areas lack access to cutting-edge treatments and clinical trials, Barragan-Carrillo says.

This disparity in clinical trial availability raises important questions about social justice and equity in health care, she continues. From a biological perspective, conducting trials in diverse populations improves the strength and generalizability of the data, as compounds may behave differently in patients from varying genetic backgrounds, Barragan-Carrillo explains. Understanding how therapies perform in different global populations enhances the overall evidence base, benefiting patients worldwide, she emphasizes. Although differences in clinical trial availability were anticipated, the magnitude of the differences in trial availability between high-income and low-income countries was striking, Barragan-Carrillo notes, adding that ORs decreased sharply as income levels declined. This highlights the urgent need for increased access to clinical trials in lower-income regions, she concludes.