Study Finds Geographic Gaps in TNBC Trial Access Persist Across US

An analysis published in Breast Cancer Research and Treatment shows clinical trials for triple-negative breast cancer (TNBC) are unevenly distributed across the United States, with rural communities, areas with greater health vulnerability, and counties with predominantly racial and ethnic minority populations facing reduced geographic access to investigational treatment options.^1,2

Investigators used ClinicalTrials.gov data from September 30, 2024, to assess 1230 US study sites alongside county-level population and demographic data. The study identified 108 active phase II and III TNBC treatment trials, including 58 (54%) for metastatic disease and 50 (46%) for nonmetastatic disease.

Overall, more than three-quarters (76.2%) of US counties had no available TNBC clinical trials, while 12.4% had exclusively federally sponsored trials, 9.7% had both federally and non-federally sponsored trials, and 1.7% had only non-federally sponsored trials.

Geographic Access to TNBC Trials

Trial availability varied by location and disease stage. Only 9.8% of rural counties had an available TNBC trial, compared with 47% of metropolitan counties. Trials for nonmetastatic TNBC were available at 93% of study sites, compared with 63% of sites for metastatic disease.

Access also differed by county-level health vulnerability and racial and ethnic composition. Among counties in the highest quartile of health vulnerability, 88.3% had no available TNBC trials, compared with 72.2% of counties in the lower 3 quartiles (P <.001). The proportion without trials was also higher in predominantly Black, Hispanic, and American Indian and Alaska Native counties than in predominantly non-Hispanic White counties.

Implications for Clinical Research

The geographic distribution of TNBC trials may limit opportunities for patients who live far from research centers. Expanding the geographic reach of TNBC trials will require greater investment in research infrastructure outside major academic centers and study designs that reduce the burden of participation. Although decentralized trials and simplified procedures may help, transportation, cost, time commitments, and eligibility restrictions remain important barriers to address.

The findings highlight the role of federally supported research in reaching underserved areas. Among rural counties with available TNBC trials, 80% relied exclusively on federally sponsored studies. The authors identified the National Cancer Institute’s National Clinical Trials Network and Community Oncology Research Program as potential avenues for expanding research access beyond major academic centers.

The lower availability of metastatic TNBC trials is also particularly relevant as patients may need studies that account for their prior treatments and clinical circumstances. With metastatic trials offered at fewer sites, patients may have fewer nearby options to consider when exploring investigational therapies.

“This study provides novel insights into the role of a pre­viously under-explored variable in perpetuating ongoing disparities in clinical trial enrollment for this particularly high-mortality malignancy,” study authors Amin et al wrote in the manuscript. “Our findings may help government, industry, and hospital-based systems prioritize their lim­ited resources to preserve and expand clinical trial access for women with TNBC, a disease in which novel treat­ment strategies are urgently needed.”

REFERENCES

1. Amin LB, Kirkwood MK, Levit LA, et al. Geographic access to triple negative breast cancer clinical trials: are trials located near patients? Breast Cancer Research and Treatment. 2026;219(3). doi:10.1007/s10549-026-08084-3

2. Recent Study Highlights Geographic Distribution of Triple-Negative Breast Cancer Clinical Trials. News release. ASCO in Action. October 19, 2026. Accessed October 21, 2026. https://tinyurl.com/yejhetwb