(T1230-02-12) Gaps in Non-Binary Populations in Clinical Trial Participation: A Comparative Analysis of Cardiovascular and Solid Tumor Studies

Purpose: Regulatory authorities like the FDA emphasize the need to improve the diversity of clinical trial participants to better reflect the demographics of potential medication users. Ensuring diversity in trial populations is vital for the generalizability of trial findings across different demographic groups. Addressing disparities in trial participation enhances the reliability and applicability of trial results.

Methods: This analysis focuses on two leading causes of death in the U.S. adult population: cardiovascular disease and cancer, which disproportionately affect certain minority groups. We examined data from all completed trials listed on clinicaltrials.gov from 2000 to 2023 related to these conditions. Our goal was to assess demographic representation within these trials and compare it with general population demographics. This comparison enables us to identify potential disparities and propose strategies for improving trial enrollment practices. It's worth noting that while some studies provided comprehensive demographic data, others only included gender breakdowns, potentially leading to lower totals for certain demographic categories due to data availability.

Results: Our analysis covered 5,492 cardiovascular and 585 solid tumors studies, involving over 13.8 million participants. Approximately 1.2 million LGBTQ adults in the United States identify as nonbinary, which constitutes eleven percent of the LGBTQ adult population. While nonbinary individuals make up a significant portion of the transgender population (about 43%), most transgender adults are not nonbinary. This works to 0.36% or about 49 times higher than their representation in reviewed Cardiovascular studies. Amongst oncology studies examined no participants were labeled as anything other than Male or Female, for demographic representation at least 437 of the roughly 121,000 should have been non-binary.

Conclusion: Our findings underscore a serious gap between the percentage of the population that is non-binary. Non-binary individuals are a traditionally extremely underrepresented group. As such, very little is known about the potential differences in drug effects on these individuals. Preliminary research suggests that differences in hormones could impact drug effectiveness and interactions. Disparities in trial participation, especially among historically underrepresented minorities, challenge the validity of trial outcomes and equitable healthcare. Current misrepresentation can compound the effect of these groups' historical lack of inclusion. Furthermore, poor representation in studies leads these minority groups to distrust the clinical trial process and are less likely to participate in clinical studies. This cycle amplifies the effect of underrepresentation in trials. However, this effect means that the effect of diversity initiatives will naturally compound itself as they work to break the cycle. Therefore, improving enrollment practices to boost participation from diverse demographic groups is imperative. This will foster more inclusive research, leading to reliable and applicable trial outcomes, ultimately benefiting all population groups. Enhancing diversity in clinical trials is not just a goal, but a necessity for the future of healthcare.

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The following is data for completed studies on solid tumors from clinicaltrials.gov with results with a completion date between 1/1/2000 and 12/31/23. There were 121,390 participants in total.


Cardiovascular studies completed between 2000-2023 (5492 studies, 13,721,001participants).