We assessed participant representation in phase 3 clinical trials registered on clinicaltrials.gov that were conducted in the U.S. between 2020 and 2024. From the 211 clinical trials analyzed, most relied on commercial IRBs (23.2%). Most of the trials in the “unknown” category were sponsored by pharmaceutical companies which likely relied on commercial IRBs. Trials relying on commercial and other/unknown IRBs had the least Black (10.4 −12.1%) and Asian (3.1–3.8%) participation as compared to Academic IRBs which had the highest Black (13.7%) and Asian (9.4%) enrollment (p < .01). Medical Center IRBs had the highest Hispanic enrollment (23.2%) compared to commercial (16.8%) and other IRBs (18.3%). When assessing the impact of the DAP, demographic composition was more varied after the DAP (p < .01). NIH and other sources of funding had greater overall participant representation, by ethnicity and race compared to industry funded trials (p < .01).
Wheeler et al. (Sat,) studied this question.