Patient Enrollment to Industry-Sponsored Versus Federally-Sponsored Cancer Clinical Trials.

Purpose: The conduct of cancer clinical research in the United States 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 might participate in industry-sponsored versus federally-sponsored cancer studies is unknown.

Methods: We evaluated trial enrollment patterns from 2008 to 2022 using ClinicalTrials.gov data. The ratio of enrollments attributable to industry versus federal sponsors was estimated. A large set of estimates on the basis of different combinations of study characteristics were generated. Point estimates were determined as the mean of combinations and confidence limits by the IQR. Five-year intervals were examined to smooth annual variation.

Results: In total, N = 26,080 studies were examined. The estimated enrollment ratio from 2018 to 2022 for all industry-sponsored versus 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). Despite increasing cancer incidence, enrollment counts for federally-sponsored trials were flat over the study period.

Conclusion: In the United States, 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.