ImportanceProstate cancer (PCa) is marked by disparities in clinical outcomes by race, ethnicity, and age. Equitable enrollment in clinical trials is fundamental to promoting health equity.ObjectiveTo evaluate disparities in the inclusion of racial and ethnic minority groups and older adults across PCa clinical trials.Data SourcesMEDLINE, Embase, and ClinicalTrials.gov were searched to identify primary trial reports from each database's inception through February 2021. Global incidence in age subgroups and US population-based incidence in racial and ethnic subgroups were acquired from the Global Burden of Disease and Surveillance, Epidemiology, and End Results 21 incidence databases respectively.Study SelectionAll phase 2/3 randomized PCa clinical trials were eligible for age disparity analyses. Trials recruiting exclusively from the US were eligible for primary racial and ethnic disparity analyses.Data Extraction and SynthesisThis study was reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Data were pooled using a random-effects model.Main Outcomes and MeasuresEnrollment incidence ratios (EIRs), trial proportions (TPs) of participants 65 years or older or members of a racial and ethnic subgroup divided by global incidence in the corresponding age group, or US population–based incidence in the corresponding racial and ethnic subgroup, were calculated. Meta-regression was used to explore associations between trial characteristics and EIRs and trends in EIRs during the past 3 decades.ResultsOf 9552 participants among trials reporting race, 954 (10.8%) were African American/Black, 80 (1.5%) were Asian/Pacific Islander, and 8518 (78.5) were White. Of 65 US trials, 45 (69.2%) reported race and only 9 (13.8%) reported data on all 5 US racial categories. Of 286 global trials, 75 (26.2%) reported the enrollment proportion of older adults. Outcomes by race and age were reported in 2 (3.1%) and 41 (15.0%) trials, respectively. Black (EIR, 0.70; 95% CI, 0.59-0.83) and Hispanic (EIR, 0.70; 95% CI, 0.59-0.83) patients were significantly underrepresented in US trials. There was no disparity in older adult representation (TP, 21 143 [71.1%]; EIR, 1.00; 95% CI, 0.95-1.05). The representation of Black patients was lower in larger trials (meta-regression coefficient, −0.06; 95% CI, −0.10 to −0.02; P = .002).Conclusions and RelevanceThe results of this meta-analysis suggest that Black and Hispanic men are underrepresented in trials compared with their share of PCa incidence. The representation of Black patients has consistently remained low during the past 2 decades.
A quantitative synthesis of disparities in the inclusion of racial/ethnic minorities and older adults in prostate cancer clinical trials over the last three decades.
26 Background: The underrepresentation of minority populations in clinical trials negatively impacts cancer and widens inequities. We aimed to quantify the enrollment disparities in prostate cancer (PC) clinical trials over the last three decades. Methods: MEDLINE and Embase were searched to identify primary reports of prostate cancer RCTs (1989-2020). Data for trial characteristics, the proportion of trials reporting race, ethnicity and age, and the proportion of patients by race, ethnicity and age enrolled in trials were summarized using descriptive statistics. Enrollment incidence ratios (EIR), which compare trial enrollment against global estimates of incidence in age-related subgroups (acquired from the Global Burden of Disease database) and U.S. population-based estimates of racial/ethnic subgroups (acquired from the SEER 18 incidence database) were calculated. Individual trial EIRs were pooled using random-effects meta-analyses to account for the substantial heterogeneity between trials. Multivariable meta-regression was used to explore associations between key trial characteristics and EIR. Annual percentage changes (APC) over the last three decades in enrollment disparities were analyzed using the Joinpoint Regression Analysis. Results: 281 trials from 1989 to 2020 with 99,588 patients were included in this analysis. 107 trials reported race (38%), of which only 25 trials (9%) reported data on all 5 U.S. racial categories (Black, White, Asian, Pacific Islander and Native American. 255 (91%) trials reported mean or median but only 71 trials (25%) specifically reported the enrollment proportion of older adults (age > 65 years). Clinical outcomes by race and age were reported in 9 (8%) and 37 (14%) trials, respectively. Results from meta-analyses showed that Black patients (summary EIR: 0.42 [95% CI: 0.35 - 0.51]), Hispanics (summary EIR: 0.50 [95% CI: 0.37 - 0.68]) and older adults (summary EIR: 0.95 [95% CI: 0.91 - 0.99]) were underrepresented in trials relative to their population estimates. Significantly fewer Black participants (EIR for Black patients = 0.42, EIR for White patients = 0.99; p < 0.0001), Hispanic participants (EIR for Hispanics = 0.50, EIR for non-Hispanics = 1.00; p = 0.001) and older adults (EIR for older adults = 0.95, EIR for younger adults = 1.06; p = 0.037) were enrolled. Representation of Black patients decreased significantly from 1989-2019 (APC: -4.25), while Hispanic representation increased significantly from 2000-2020 (APC: 5.89). Meta-regression showed Black patients were particularly underrepresented in larger-size trials (p < 0.0001). Conclusions: Black representation in PC clinical trials is less than 50% of their expected share based on cancer incidence and it has consistently decreased over last three decades, contributing to the disparities experienced by the population.