Ten-Year Trends in Enrollment of Women and Minorities in Pivotal Trials Supporting Recent US Food and Drug Administration Approval of Novel Cardiometabolic Drugs

Abstract

Background In 1993, the US Food and Drug Administration established guidelines to increase diversity by sex and race/ethnicity of participants in clinical trials supporting novel drug approvals. In this study we investigated the 10-year trends of participation of women and minorities in pivotal trials supporting approval of new molecular entities in cardiometabolic drugs from January 2008 to December 2017. Methods and Results A list of new molecular entities was abstracted from publicly available data at Drugs@Fda. Sex and race/ethnicity data were collected from trial publications. Linear regression analysis was performed to assess the relation between drug approval year and proportion of women and minorities enrolled. Thirty-five novel cardiovascular (n=24) and diabetes mellitus (n=11) drugs were approved by the US Food and Drug Administration during the study period. The median number of participants supporting each drug was 5930 (interquartile range, 3175-10 942). Women represented 36% (n=108 052) of trial participants (n=296 163). Women were underrepresented compared with their proportion of the disease population in trials of coronary heart disease (participation-to-prevalence ratio, 0.52), heart failure (participation-to-prevalence ratio, 0.58), and acute coronary syndrome (participation-to-prevalence ratio, 0.68). Among trial participants, 81% were white, 4% black, 12% Asian, and 11% Hispanic/Latino. There was no significant association between enrollment of women (P=0.29) or underrepresented minorities (P=0.45) with the drug approval year. Conclusions Over the past decade (2008-2017), women and minorities, particularly blacks, have continued to be inadequately represented in pivotal cardiometabolic clinical trials that support US Food and Drug Administration approval of new molecular entities. This may have major implications in determining efficacy of such therapies in these groups, and may impair generalizability of trial results to routine clinical practice.

Keywords: cardiometabolic drugs; clinical trials; minorities; women.

Figure 1. Percentage of men and women participating overall in cardiovascular and diabetes mellitus pivotal drug trials according to year of drug approval.

Figure 2. Participation of women in pivotal drug trials: prevalence‐corrected estimate.

*Coronary heart disease participation‐to‐prevalence ratio was dependent upon 1 trial, so the 95% CI could not be calculated.

Figure 3. Comparison of overall percentage of whites and blacks enrolled in pivotal cardiovascular and diabetes mellitus drug trials according to year of drug approval.