Abstract C164: Underrepresentation of Black and elderly populations in immunotherapy-based clinical trials for gynecologic cancers: Trends over the past two decades

Abstract BACKGROUND: Race-based disparities in gynecologic oncology (GYN-ONC) clinical trials are well-documented. In 2012, the FDA introduced the Safety and Innovation Act (FDASIA) to improve the reporting and inclusion of demographic minorities in clinical trials. Also, the first immune checkpoint inhibitor (ICI), Ipilimumab, received FDA approval in 2011, which opened a new era of ICI-based clinical trials in several cancer types, including Gyn cancers. Here we assessed trends in race- and age-based disparities pre- and post-introduction of the FDASIA in a subset of GYN-ONC clinical trials investigating immunotherapy. METHODS: Phase 1-3 trials were identified using the following search terms on ClincialTrials.gov: ovarian cancer (OvCa), endometrial cancer (EnCa), cervical cancer (CxCa), immunotherapy, adoptive cell therapy, vaccine, ICI. Trials without posted/published results were excluded. Enrollment, race, ethnicity, and age data were extracted from the clinical trials page and/or associated manuscripts. Using CxCa, EnCa and OvCa prevalence data from the 2021 SEER database, we calculated expected enrollment proportions by race and age, respectively, and compared these to actual clinical trial enrollment data. Binomial and chi-squared tests were used for statistical analyses. RESULTS: 252 clinical trials were initially identified. 123 trials (48.8%), opened between 2002-2020, remained after removing ongoing trials without published/posted results. Of the 123 trials, 58 (47%) reported both race and ethnicity (RAE) data; 26 (21.1%) reported only racial demographics; and 39 (31.7%) did not report RAE data. 71.2% (71/99) of studies that opened from 2013-2020 reported RAE data compared to 50% (12/24) from 2002-2012 (OR: 2.54, 95% CI: 1.04-6.18, p=0.05). 84 trials (58 with RAE, and 26 with only race) had evaluable data for 12,433 participants. Black patients had lower enrollment (3.9%; 47% of expected enrollment) vs. White patients (69.7%; 81% of expected enrollment, P<0.0001) compared to the distribution of race (White: 86.3%, Black: 8.4%, Asian: 4.9%) of all three GYN cancers in the US. In trials that opened between 2013-2020 vs. 2002-2012, the proportion of Whites entering trials decreased (68.6% vs. 94.1%, OR: 0.14, 95% CI: 0.10-0.19, p<0.0001), while there was no change in the proportion of Black enrollment ( 4.0% vs. 3.1%, OR: 1.32, 95% CI: 0.82 to 2.14, p=0.27). On the other hand, there was an increase in the proportion of Asian participants (17.7% vs. 2.0%, OR: 10.65, 95% CI: 5.93-19.28, p<0.0001) and the proportion of other/unknown participants (9.8% vs. 0.9%, OR: 11.96, 95% CI: 5.17-27, p<0.0001). Enrollment of elderly groups did not change significantly between 2002-2012 (37.2%) vs. 2013-2020 (27.0%, OR: 0.78, 95% CI: 0.50-1.24, p=0.27). CONCLUSIONS: RAE reporting trended to increase after the introduction of the 2012 FDASIA, however, Black and elderly populations were still underrepresented. Continued efforts should be made to improve RAE reporting as well as enrollment of Black and elderly populations in Gyn cancer immunotherapy trials. Citation Format: Maheen Khan, Kristen Ibanez, Duncan Donohue, Courtney Bowen, Jung-Min Lee. Underrepresentation of Black and elderly populations in immunotherapy-based clinical trials for gynecologic cancers: Trends over the past two decades [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C164.