Patient enrollment to industry- versus NIH-sponsored cancer clinical trials.

46 Background: The conduct of cancer clinical research in the U.S. is supported by both private and public sponsors. Industry aims to obtain new drug approvals. Federally-sponsored trials examine a broad set of research questions that are not typically addressed by industry; these trials, which are also more commonly conducted in diverse populations, were recently shown to have contributed to gains of 14 million life-years for patients with cancer. Despite the different mandates, the proportion of patients who participate in industry vs. federally-sponsored cancer studies is unknown. Methods: We evaluated trial enrollment patterns from 2008-2022 using ClinicalTrials.gov data. The ratio of enrollments attributable to industry versus federal sponsors was estimated. A large set of 990 estimates based on different combinations of study characteristics were generated. Point estimates were determined as the mean of combinations and confidence limits by the interquartile range (IQR). Five-year intervals were examined to smooth annual variation. Results: N=26,080 studies were examined. The estimated enrollment ratio from 2018-2022 for all industry vs. federally-sponsored trials was 8.1 (IQR:6.2-9.9). For adult trials, the ratio increased from 4.8 (IQR:4.4-5.3) during 2008-2012 to 9.6 (IQR:7.4-11.8) during 2018-2022; for trials in children, the ratio increased from 0.7 (IQR:0.6-0.7) to 2.3 (IQR:1.8-2.7). For adult trials, annual enrollment attributable to industry sponsorship increased from 54,127 in 2008-2012 to 113,527 for 2018-2022. In contrast, annual enrollment counts for federally-sponsored trials were flat over the entire study period, including 11,282/year for 2008-2012 and 11,798/year in 2018-2022, even as incident cancer cases in the U.S. increased 18% from 1.53 million in 2010 to 1.81 million in 2020. Conclusions: In the U.S., there is a growing reliance on industry to conduct cancer clinical research. Underinvestment in federally-sponsored research comes at a cost for both patients and researchers, with lost opportunities for scientific, clinical, and population advances.