Access to cancer treatment trials in areas prone to extreme weather events: An ASCO State of Cancer Care in America analysis.

139Background: Extreme weather events are increasingly common in the US and have the potential to disrupt cancer care. An ASCO analysis found that 65% of oncologists work and 65% of Americans newly diagnosed with cancer reside in or near areas prone to extreme weather events. Here, we analyze the geographic distribution of cancer treatment trials relative to areas prone to extreme weather events. Methods: Site information for phase I-III cancer treatment trials in the US was extracted from clinicaltrials.gov as of 9/30/2024. Active trials initiated in 2015 or later with status of not yet recruiting, recruiting, active not recruiting, and enrolling by invitation were included. Trial sites were geocoded and trials were tabulated by county. Demand for trials was approximated using 2017-2021 average annual counts of new cancer cases by county from State Cancer Profiles. We extracted US Climate Vulnerability Index county rankings for extreme flooding, storm, and wildfire events, and for community resilience (derived from health, socioeconomic, infrastructure, and environmental measures). We defined “high-risk” counties as those with the highest decile rankings for extreme flooding, storm, and/or wildfire events across all US counties and determined the share of trials and people with incident cancer in those areas. Trials and populations in counties adjacent to high-risk counties were also identified because they might be affected by extreme weather events or by patients diverting care to these areas. Among high-risk and adjacent counties, we identified the subset ranked in the highest quartile for baseline community vulnerability (i.e., low community resiliency). Results: Of 7142 trials active at 1796 US sites, 6229 (87%) are located in a high-risk or adjacent county prone to extreme weather events (5086 trials [71%] are located directly within a high-risk county). Furthermore, 5146 trials (72%) are located in counties identified as both (1) high-risk or adjacent counties for extreme weather events, and (2) high baseline community vulnerability. Of 902 US counties with trials, 495 (55%) are at risk for weather-related disruption (258 high-risk for extreme weather events and 237 adjacent counties). Of the estimated 1.7 million people newly diagnosed with cancer, about 950, 000 (55%) live in counties with trials that are high-risk or adjacent for extreme weather events, 178K of whom live where community resiliency is low. Conclusions: Most cancer treatment trials are located in or near counties prone to extreme weather events, many with high baseline vulnerability. Sponsors, regulators, sites, and others should collaborate on emergency preparedness plans to ensure continuity of care and to preserve trial access and integrity. Plans could build on lessons learned from prior trial disruptions, such as the flexibilities adopted during the COVID-19 pandemic and decentralized trial designs.