Improving diversity in phase I oncology clinical trials: A single institution experience at the University of Colorado Cancer Center.
Authors: Alsafar Ahmed , Kareem Sama , Corr Bradley , Lieu Christopher Hanyoung , Wilky Breelyn A. , Davis S. Lindsey , Camidge David Ross , Jimeno Antonio , Nicklawsky Andrew , McDermott Jessica Dreger , Diamond Jennifer Robinson 
Published: May 2024

e13687 Background: Despite continued improvements in cancer outcomes, disparities persist between racial, ethnic, and socioeconomic groups. One potential driver is the lack of appropriate representation in clinical trials, including dose-finding studies. We implemented a set of initiatives including patient education, outreach, a Spanish-speaking bicultural clinic, and regular review of enrollment by race and ethnicity. To investigate the impact of these initiatives, we examined phase I clinical trial patient demographics and treatment outcomes before and after the intervention. Methods: We performed a retrospective review of patients enrolled in 2018-2019 (cohort 1[C1], pre- intervention) and 2022-2023 (cohort 2[C2], post-intervention). We collected patient demographics, area deprivation index (ADI), body mass index (BMI), ECOG performance status, and tumor type. Differences between cohorts were evaluated with T-tests, Chi-Square test, or the Fisher Exact test. Progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier method. Hazard ratios (HR), confidence intervals (CI) and p values were derived using the cox proportional hazards method. A multivariable model for patients with colorectal cancers (CRC) was selected using the Akaike information criterion (AIC). Results: A total of 361 patients (C1 n = 209, C2 n = 152) were included. Overall, 52.4% of patients were female. The most common tumor sites were CRC (18.3%), pancreas (11.9%) and breast (10.8%). Study participants were 85.0% White, 3.3% Asian, 1.4% Black and 9.1% Hispanic, compared to cancer incidence in Colorado of 92.8%, 1.6% and 3.3% and 10.0%, respectively. Following our intervention, there was an increase in language preference other than English from 1.9% (4/209) to 6.6% (10/152) (p = 0.028) and in translated consents from 1.4% (3/209) to 5.9% (9/152) (p = 0.033). There was no statistically significant difference in race, ethnicity, insurance, or tumor type, although there was a non-statistically significant increase in Hispanic patients from 8.1% to 10.5%. Median PFS improved from 1.9 to 2.8 months (HR = 0.72, 95% CI 0.57-0.90, p = 0.003). ECOG 1 v. 0 was associated with inferior OS (HR = 1.35, 95% CI 1.06-1.73, p = 0.017), and BMI ≥18.5 v. <18.5 was associated with superior OS (HR = 0.59, 95% CI 0.37-0.95, p = 0.03). AIC model of CRC (n = 66) revealed that ADI scores of 6-10 were associated with worse PFS and OS (p = 0.022 and p = 0.001, respectively). Conclusions: Our interventions resulted in an increase in accrual of non-English speaking patients, however, there was not yet a statistically significant change in overall race and ethnicity. Our study confirms poorer clinical outcomes for patients with higher ADI scores. Further research and intervention are warranted to mitigate disparities in clinical trial accrual and improve clinical outcomes for disadvantaged patients.