Trials of pulmonary/respiratory, neurology and rheumatology therapies have the lowest representation of African Americans and other ethnic minorities, while Hispanic/Latinx populations are the most underserved in pivotal oncology trials.

Asian populations, on the other hand, are overrepresented in most therapeutic areas, and that imbalance has continued to grow since 2007.

These are some of the key findings of new research from the Tufts Center for the Study of Drug Development (CSDD), which each year examines compiled clinical trial and participant demographic data on all new drugs and biologics approved by the FDA. Between 2007 and 2017, the FDA approved 371 new products.

CSDD found that participants who identify as black or of African descent were the most underrepresented demographic group, with nearly 47,000 fewer participants than expected, based on disease prevalence and census population data. African Americans were underrepresented by more than 20 percent of the expected level in 80 percent of all drugs and biologics approved by the FDA during the period studied, the report said.

“Other” participants (e.g., indigenous people) and Hispanic/Latinx participants were also underrepresented, but to a lesser extent, with 11,642 and 4,669 fewer participants than expected, respectively, CSDD researchers found.

Asian participants, CSDD researchers reported, were highly overrepresented, due in part to global demographic requirements and classification practices in which an individual’s race and/or ethnicity may be categorized differently in different parts of the world. This overrepresentation of Asian participants in pivotal trials continued to grow, from 26 percent for 2007 to 2010 approvals to 161 percent for 2014 to 2017 approvals.

However, Asian participants were underrepresented in gastroenterology- and rheumatology-focused trials, the researchers observed.

Diversity by gender has improved over time, with five percent fewer female participants than male participants in pivotal trials from 2007 to 2010 compared to no disparity from 2014 to 2017. Forty-five percent of all participants in clinical trials supporting FDA approvals during 2007 to 2017 were female, short of an expected 49 percent based on gender distribution by disease prevalence and population census. Approximately 20,000 fewer females were enrolled in pivotal trials than expected.

Overall, 252,586 women and 309,844 men participated in pivotal clinical trials during the time period examined.