Despite being more likely to be diagnosed with triple negative breast cancer (TNBC), Black women remain underrepresented in clinical trials across the U.S. While distance from trial sites may not be a primary reason for this disparity, a new analysis finds that millions of women live in areas without access to trials, pointing to uneven trial availability nationwide.
The study, presented at the 2025 American Society for Clinical Oncology (ASCO) annual meeting in Chicago, looked at all registered active phase 2 and 3 interventional treatment trials as of September 2024, pulling together the number of trials per U.S. county and using census data to investigate demographical differences in trial availability.
Researchers found that while most U.S. study sites had multiple TNBC trials available, around one-third (37%) of the sites assessed offered no trials specifically for metastatic TNBC, which suggests that barriers to finding an applicable trial exist even when physically near a trial site. Still, state-level differences in trial availability were observed, making expanding the geographic reach of clinical trials a key priority.
David Waterhouse, M.D., who chairs ASCO’s State of Oncology Care in America (SOCCA) Committee and was one of the study’s authors, considers changing “how we think about trials” to ensure greater accessibility an “enormous thing,” he told Fierce Biotech in an interview at this year’s ASCO meeting.
SOCCA’s research into the issue of disproportionate trial accessibility and participation goes way back and is still ongoing, as the latest findings only address “one smaller question, which is part of a much bigger question,” he noted. Last year, Waterhouse and others published a sweeping report on geographic access to cancer trials in the U.S., finding that just 1 in 50 of nonmetropolitan counties boasted broad trial portfolios, and 86% of those countries had no clinical trials at all.
The problem of widening the geographic availability of clinical trials is “hard,” Waterhouse acknowledged. However, it all comes down to “how much we want to prioritize it and choose to change,” he said.