Racial distribution of clinical trial participants in the United States.

Abstract

e18516 Background: Lack of diverse representation in clinical trials negatively impacts the cancer survival of patients and populations unaccounted for in clinical research. Efforts such as the 1993 NIH Revitalization Act have focused on improving the diversity of trial participants in the US. This retrospective study evaluated the racial distribution of oncology clinical trial participants using data published in clinicaltrials.gov from Jan 2010 through Dec 2020. Methods: I2E of Linguamatics (IQVIA, Inc), a natural language processing software, was used to identify participant race in oncology trials. Data extracted included trial identifier, year of completion, sponsor, cancer type, and race. Studies were limited to academic, cooperative group and government studies headquartered in the US. Clinical trial results were compared to the racial distribution of SEER 2010 data using z-test. Results: Data from 35,686 patients (14,220 enrolled to 236 phase 2 and 21,471 enrolled to 47 phase 3 trials) were available for analysis. A summary by race is provided in the Table, excluding unknown, which represented 8.5% of phase 2 and 3.5% of phase 3 trials. The proportions of white/black patients enrolled to phase 2 and phase 3 trials beginning in 2010-12 were 84.4%/11% and 83.1%/9.9%, respectively (total enrollment 84.9%/9.6%). For trials beginning in 2015-17, white/black enrollment represented 88.5%/8.1% of patients enrolled to phase 2 and 86.4%/10.1% of patients in phase 3 trials. Black patients represented 9.6% of all trial participants, in contrast with the SEER data where 12% of all patients were black (p < 0.001). For lung cancer trials, black participants represented only 7.9% of all trial participants whereas in breast cancer trials, 10.2% of participants were black, versus the SEER data specific to these tumor types (black patients represent 10.9%/11.5% of lung/breast cancer diagnoses between 2013 to 2017, both p < 0.01). Conclusions: This study suggests that over the past decade most races (other than white) have been significantly underrepresented in US oncology clinical trials, and is even more pronounced for black patients with lung cancer. Based on this analysis, there is no evidence that trial enrollment distribution, particularly of white versus black participants, has changed since 2010. Data are limited to the relative lack of studies reporting results that began enrollment after 2017. These findings suggest that the development of new strategies to improve the recruitment of racial minorities to oncology clinical trials are warranted.[Table: see text]