Understanding the link between Medicaid expansion and participation in cancer clinical trials

From Dr. Unger and Colleagues, SWOG, Public Health Sciences Division

Cancer clinical trials are the foundation of advancing new therapies and making these therapies available for patients. Treatments that make it through pre-clinical testing to comparative testing in clinical trials hold promise for bettering the lives of people with cancer. Unfortunately, the cost of participating in a cancer clinical trial is prohibitive for many, especially for patients from socioeconomically vulnerable communities. The implementation of the Patient Protection and Affordable Care Act (ACA) led to changes in whether and how patients obtain insurance and offered new protections for patients. The ACA’s Medicaid expansion in 2014 resulted in an increase in patients with cancer using Medicaid insurance. Dr. Joseph Unger, an Associate Professor in the Fred Hutchinson Cancer Center’s Public Health Sciences Division and biostatistician working with the Southwest Oncology Group (SWOG), and colleagues asked the question whether this Medicaid expansion also resulted in more patients with Medicaid insurance enrolling onto clinical trials. Their study, recently published in JAMA Oncology, focused on assessing improved access to cancer clinical trials in the timeframe since states adopted the Medicaid expansion. 

The adoption of the Affordable Care Act Medicaid expansion in 2014 resulted in an increased number and proportion of people with Medicaid participating in cancer clinical trials.
The adoption of the Affordable Care Act Medicaid expansion in 2014 resulted in an increased number and proportion of people with Medicaid participating in cancer clinical trials. Figure sourced from Wiki Commons. This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International License. Dated August 18th, 2023.

For their study, the authors assessed cancer clinical trial enrollments as part of the SWOG Cancer Research Network from 1992 to 2020, right before the onset of the Covid-19 pandemic. By using an interrupted time series statistical model, and the initial implementation of the Medicaid expansion (2014) as an independent variable, they assessed changes in enrollment patterns by insurance use. They analyzed 51,751 patients, of whom 4,709 (9.1%) had Medicaid coverage. Medicaid use was significantly higher among minoritized populations. Overall, they noted an increase in Medicaid insurance use from the pre-expansion period (pre-2014) to post expansion, of just over 3%. Notably, the authors also observed that the number of clinical trial patients using Medicaid fluctuated in line with changes to the economy, i.e., when unemployment rates were higher, patients insured by Medicaid more commonly participated in trials, and vice versa. After the Medicaid expansion and adoption by many states, the authors noted a 19% annual increase in odds of patients being insured by Medicaid – with female patients more likely to use Medicaid than male patients. The association was predominantly observed among states that implemented the Medicaid expansion in 2014 and 2015.  

As the authors highlighted in their concluding paragraph “these findings are important because they suggest that socioeconomically vulnerable patients have better access to the newest treatments in trials because of this policy change. This result is also critical for researchers and clinicians because improved participation of socioeconomically vulnerable patients in trials improves confidence that trial findings will apply to all patients.”

This work was funded by the National Institutes of Health, National Cancer Institute, National Clinical Trials Network, Hope Foundation for Cancer Research, and the American Cancer Society.

Fred Hutch/University of Washington/Seattle Children's Cancer Consortium members Dr. Joseph Unger and Dr. Michael LeBlanc contributed to this work.

Unger JM, Xiao H, Vaidya R, LeBlanc M, Hershman DL. Medicaid Expansion of the Patient Protection and Affordable Care Act and Participation of Patients With Medicaid in Cancer Clinical Trials. JAMA Oncol. 2023 Aug 17:e232800. doi: 10.1001/jamaoncol.2023.2800. Epub ahead of print. PMID: 37590003; PMCID: PMC10436183