Journal of geriatric oncology | 2021
Disparities in older adult accrual to cancer trials: Analysis from the alliance for clinical trials in oncology (A151736).
Abstract
BACKGROUND\nOlder adults are under-represented in cancer clinical trials. However, it remains unclear which types of trials under-enroll aging patients. We aimed to identify associations between trial characteristics and disparate enrollment of older adults onto trials sponsored by the Alliance for Clinical Trials in Oncology (Alliance).\n\n\nMETHODS\nActual age\xa0≥\xa065 percentage and trial data were extracted from the Alliance closed study list. Each trial, based on its cancer type and years of enrollment, was assigned an expected age\xa0≥\xa065 percentage extracted from the Surveillance, Epidemiology, and End Results (SEER) US population-based database. Enrollment disparity difference (EDD), the difference between the expected age\xa0≥\xa065 percentage and the actual age\xa0≥\xa065 percentage, was calculated for each trial. Linear regression determined trial variables associated with larger EDDs and variables with an overall association p-value <0.20 were included in a multivariable fixed-effects linear model.\n\n\nRESULTS\nThe median age of 66,708 patients across 237 trials was 60\xa0years (range 18-102). The average actual age\xa0≥\xa065 percentage enrolled per trial was lower than each trial s expected age\xa0≥\xa065 percentage average (39% vs. 58%; EDD 19, 95% CI 17.1-21.3%, p\xa0<\xa00.0001). In multivariable analyses, non-genitourinary (GU) cancer types (p\xa0<\xa00.001), trimodality+ trials (estimate 8.78, 95%CI 2.21-15.34, p\xa0=\xa00.009), and phase 2 trials (estimate 4.43 95% CI -0.06-8.91; p\xa0=\xa00.05) were all associated with larger EDDs.\n\n\nCONCLUSIONS\nDisparate enrollment of older adults is not equal across cancer trials. Future strategies to improve older adult inclusion should focus on trial types associated with the highest disparate enrollment.