US regulatory agency makes ‘big change’ to increase the number of participants from under-represented groups in drug testing.

The US Food and Drug Administration (FDA) will soon require researchers and companies seeking approval for late-stage clinical trials to submit a plan for ensuring diversity among trial participants.

Many scientists have applauded the move, which was laid out in a spending bill signed into law by US President Joe Biden in December 2022. They say that broadening participant pools is important to make medicines more effective across the whole population. But they are not yet convinced that the FDA will adequately enforce the new requirement.

Nonetheless, “this is the biggest change in the regulatory landscape for clinical-trial diversity in the last three decades”, says Thomas Hwang, a physician at the Dana-Farber Cancer Institute in Boston, Massachusetts, who has expertise in pharmaceutical regulation¹.

Stalled efforts
The diversity requirement arrives in the wake of a 2022 report from the US National Academies of Sciences, Engineering and Medicine, which found that, although the representation of white women in clinical trials has improved, progress has “largely stalled” for minority racial and ethnic groups. Older adults, pregnant people and individuals with disabilities remain severely under-represented — and, in some cases, excluded — from US clinical research, the report found. For example, a recent analysis of new cancer therapeutics approved by the FDA between 2012 and 2017 found that 79% of the clinical trials that were used to support the FDA’s decisions adequately represented women — but only 27% adequately represented older adults, and only 11% met the bar for minority racial and ethnic groups2. (In this case, ‘adequately represented’ means that the percentage of, say, women enrolled in a cancer trial approximately matches the proportion of women in the United States who have that type of cancer.)