Background: Tufts CSDD conducted a study to quantify the magnitude of participant subgroup demographic disparities in industry-funded pivotal trials and establish baseline participant diversity measures.
Methods: Eleven years of data on pivotal trials of all novel drugs and biologics approved between 2007 and 2017 (n = 341 drugs and n = 757 pivotal trials) was compiled and analyzed.
Results: The availability of reported participant demographic subgroup data was poor-most notably participant ethnicity with 63% of pivotal trials supporting all approved treatments missing data. The availability of data on participant race and ethnicity did not improve between 2007 and 2017. Participants of Black or of African Descent were the subgroup most highly under-represented. Three times as many participants in this demographic subgroup should have been enrolled in pivotal trials to achieve representation as dictated by disease prevalence rates and population census figures. Although variation was observed between disease conditions, under-representation of Black/African Descent participants occurred in nearly all conditions. Participants from indigenous communities were also highly under-represented. Asian participants were highly over-represented in pivotal trials. Approximately 14% more Hispanic/Latinx participants should have been enrolled in clinical trials to achieve population-proportional representation.
Conclusions: The results suggest that participant demographic disclosure practices are falling short and that insufficient diversity in clinical trials is limiting the value of guidance on medical treatment dosing and response. The study findings supplement the FDA's Drug Trial Snapshot Reports and offer insight into the magnitude of, and trends in, participant demographic subgroup disparities.
Keywords: Demographics; Disparity; Diversity; Ethnicity; Race; Representation.