Sociodemographic disparities among patients referred externally for clinical trials in a community oncology setting.

125 Background: Clinical trial enrollment rates in community oncology settings- where the majority of patients with cancer are treated- are far lower than enrollment rates at academic centers. Barriers to enrollment include lack of trial awareness among patients and oncologists, geographic and transportation challenges, insurance concerns, and lack of care coordination between healthcare systems. These barriers may be heightened for patients from historically racial/ethnic minoritized groups, socioeconomically disadvantaged backgrounds, or those with language barriers. This study compared sociodemographic characteristics of adults with cancer referred to external institutions for interventional cancer clinical trials to the overall population in a large community oncology practice and integrated health system. Methods: A retrospective analysis was performed using Kaiser Permanente Northern California referral data to identify patients referred externally for interventional cancer clinical trials from 1/1/2023-12/31/2023. Patients with Medicare plans were excluded as they are self-referred to clinical trials outside of KPNC. Sociodemographic and clinical characteristics were compared to an incident non-Medicare cohort of patients with newly diagnosed cancer between 6/1/2022-5/31/2023, adjusting for lag times in the KPNC registry. Statistical analyses included Pearson chi-squared, binomial, and one-sample t-tests. Results: 110 patients were externally referred for clinical trials over the study period and were compared to the incident cancer cohort (n = 3395). 97 referrals were within Northern California. Referred patients were more likely to come from high socioeconomic neighborhoods (40% vs 24%), have distant SEER staging (70% vs 13%), and have rarer tumor types, such as sarcoma (9% vs 1%) or brain malignancy (7% vs 1%), compared to the incident cohort. A higher proportion of male patients were referred (56% vs 38%) (all p-values < 0.05). There were no differences in enrollment based on race/ethnicity (49.6% non-White vs 50.4% White), age, or primary language spoken. Conclusions: Patients with higher SES, rare tumor types, metastatic disease, and male sex were more highly represented among those referred for external trials. Notably, there were no differences in enrollment by race or ethnicity in a diverse sociodemographic cohort, which may reflect the benefits of an integrated health system in facilitating access to trials. As trials become more complex and personalized in the era of precision oncology studies, community and academic health systems must partner to facilitate equitable access to clinical trials.