Biomarker Testing, Targeted Therapy and Clinical Trial Participation by Race Among Patients With Lung Cancer: A Real-World Medicaid Database Study

Introduction

Biomarker testing in oncology is fundamental for targeted therapy use and clinical trial participation. Factors contributing to previously identified racial disparities in biomarker testing remain unclear. This study investigated biomarker testing, clinical trial participation, and targeted therapy by race among patients with metastatic lung cancer with Medicaid coverage in the United States.

Methods

The Merative MarketScan Medicaid claims database was used for this study to identify patients diagnosed with having metastatic lung cancer between 2017 and 2019 with at least 121 days of follow-up. Racial differences in biomarker testing, clinical trial enrollment, and targeted therapy use were analyzed using chi-square/t tests followed by logistic regression for confounding covariates.

Results

A total of 3845 patients were eligible. A total of 970 (25.2%) patients included in this study were Black. Biomarker testing was observed among 57.0%, targeted therapy among 4.6%, and 2.6% of the study cohort had evidence of clinical trial participation. No significant disparities between Black and White races were identified. Younger age and metastatic disease at initial diagnosis were the strongest independent factors associated with increased biomarker testing. Biomarker testing was positively associated with targeted therapy use (OR = 1.69, p = 0.005).

Conclusions

Patients with metastatic lung cancer with Medicaid coverage were found to have exceedingly low biomarker testing rates; only 57% had evidence of any biomarker testing. Although no consistent differences between Black and White races were identified, this study calls attention to care experienced by socioeconomically disadvantaged patients with metastatic lung cancer in the United States.