Ineligible, Unaware, or Uninterested? Associations Between Underrepresented Patient Populations and Retention in the Pathway to Cancer Clinical Trial Enrollment

Abstract

PURPOSE: Cancer clinical trials can benefit current and future patients; however, Black patients, rural residents, and patients living in disadvantaged areas are often underrepresented. Using an adapted version of Unger and colleagues' model of the process of clinical trial enrollment, we evaluated the relationship between underrepresented patient populations and trial end points. METHODS: This retrospective study included 512 patients with breast or ovarian cancer who were prescribed a therapeutic drug at the University of Alabama at Birmingham from January 2017 to February 2020. Patient eligibility was assessed using open clinical trials. We estimated odds ratios and 95% CIs using logistic regression models to examine the relationship between underrepresented patient populations and trial enrollment end points: eligibility, interest, offer, enrollment, and declining enrollment. RESULTS: Of the patients in our sample, 27% were Black, 18% were rural residents, and 19% lived in higher disadvantaged neighborhoods. In adjusted models, each comparison group had similar odds of being eligible for a clinical trial. Black versus White patients had 0.40 times the odds of interest in clinical trials and 0.56 times the odds of enrollment. Patients living in areas of higher versus lower disadvantage had 0.46 times the odds of enrolling and 3.40 times the odds of declining enrollment when offered. CONCLUSION: Eligibility did not drive clinical trial enrollment disparities in our sample; however, retention in the clinical trial enrollment process appears to vary by group. Additional work is needed to understand how interventions can be tailored to each population's specific needs.

Integrating primary care, shared decision making, and community engagement to facilitate equitable access to multi-cancer early detection clinical trials

“…Many populations with disparities in cancer screening also are underrepresented in clinical trials, including racial and ethnic minority groups, individuals of low socioeconomic status and rural residents ( 12 , 13 ). Disparities are noted at eligibility, interest in participation and actual enrollment ( 14 ). There are many established reasons for lower enrollment of these groups, including transportation, cost, trust in medical system, and patient knowledge or comprehension of the research ( 15 ), and multi-level interventions are needed to increase enrollment of underrepresented populations ( 16 ).…”

Strengths and opportunities to clinical trial enrollment among BIPOC, rural dwelling patients in the northwest United States: a retrospective study

“…Yet, participation in CTs has remained low for more than 20 years, particularly among community sites (4%) when compared to National Cancer Institute (NCI) designated sites (19%) ( Unger and Fleury, 2021 ). In addition to the practice site, health status, race and ethnicity, rurality, and socioeconomic status influence clinical trial enrollment ( Caston et al, 2022a ; Caston et al, 2022b ).…”

“…This underrepresentation limits the ability to generalize trial results to diverse patient populations. Lack of CT representation is well documented for patients who are Black, Indigenous, People of Color (BIPOC), rural residents, or patients living in disadvantaged areas ( Caston et al, 2022a ; Caston et al, 2022b ). Lack of CT representation is particularly low among indigenous populations; only 1% of participating individuals are American Indian/Alaska Native (AI/AN) - a disproportionately low level ( Mainous et al, 2023 ).…”