As U.S. ditches diversity in clinical trials, focus turns to Europe

The United States once led the world in running clinical trials that aimed to look like the nation at large. Now it is dumping equality goals and slashing health research, so experts are looking to Europe to plug the diversity gap.

Racial health inequality manifests in many ways - be it discriminatory treatment or higher death rates - but one glaring disparity kicks in at the get-go with the testing of all drugs, medical devices and treatments pre-launch.

Studies show that ethnic minorities are far less likely to volunteer for such trials, a fact that health experts put down to mistrust of the health system, fear and misinformation.

So when the pandemic showed that Black, Asian, Hispanic and other minority communities were worse hit by COVID-19 than white populations, governments, researchers and pharmaceutical firms all committed to greater diversity in future clinical trials.

Recruiting more volunteers from different genders, sex, ages and ethnic groups is key to treating diseases more effectively and addressing disparities, health experts say.

Population diversity

The United States was the first country to require companies to test medicines and devices in diverse populations when it brought in draft guidance in 2022, due to be finalized this year.

"Diversity in clinical trials is not about an ideological position. It's about scientific accuracy and medical progress," said Joshua Sharfstein, a former top official at the U.S. regulatory body the Food and Drug Administration (FDA).

But that progress now hangs in limbo as President Donald Trump's administration guts staff and funding from health departments, and scrubs diversity, equity and inclusion (DEI) policies from federal agencies.

The FDA's Diversity Action Plan draft guidance was among several U.S. government webpages removed in January due to "gender ideology" before a court order reinstated it.

Researchers and health campaigners say it is unclear whether the United States will now implement the diversity guidance, as mandated by the 2022 Food and Drug Omnibus Reform Act.

The FDA and the U.S. Department of Health and Human Services, which oversees the agency, did not immediately respond to requests for comment.

The government on Tuesday began cutting 10,000 jobs at public health agency the Centers for Disease Control and Prevention, the FDA, and the National Institutes of Health, the leading funder of global medical research.

"It's a very chaotic situation and one hopes for the best and one fears for the worst," said physician Robert Steinbrook, director of health research at U.S. advocacy group Public Citizen.

"If the FDA were to abandon the scientific progress that has been made because of 'gender ideology' or other concepts which are quite ambiguous... it would be a big step backwards," he said.

Under-represented, under-served

Samantha Artiga, director of racial equity at U.S. health policy group KFF, said positive post-COVID initiatives could lose momentum under Trump.

"We're likely to continue to see under-representation of groups in trials, particularly people of color and women and other historically under-served groups," she said.

A 2022 Lancet paper analyzing 20 years of studies showed that less than half of all U.S.-based trials included race and ethnicity data.

Despite Black patients representing 21 percent of COVID deaths, they made up only 3 percent of U.S. vaccine trials, the study reported.

Mayur Murali, a researcher at Imperial College London, found similar trends in a 2023 paper studying British vaccine take-up.

Asian volunteers made up 5.8 percent of all the COVID vaccine trials analyzed and 1 percent of Black people were included despite these populations having higher mortality rates than white people, according to official data.

Fear and mistrust of the health system contributed to their exclusion from the trials, said Murali.

"With COVID-19 vaccine hesitancy for example, there was a lot of mistrust amongst ethnic minority communities and a lot of it was to do with misinformation and feeling locked out."

According to a 2024 survey of over 8,000 people by research group Ipsos, 41 percent of ethnic minorities were willing to volunteer in a trial compared to 61 percent of white respondents, citing fear of side-effects and mistrust of pharmaceutical companies.

"If you can make that process transparent ... I think people would be very happy to be involved," Murali said.

Taking the lead

With the United States turning its back on diversity initiatives, researchers hope Europe will step up.

"I'm worried that the U.S. is not talking about equity, diversity and inclusion anymore," said Sonia Anand, a professor of medicine and epidemiology at McMaster University in Canada.

"I really hope that these other governments will continue along the path to promoting the importance of equitable inclusion into clinical trials."

There are promising signs. The World Health Organization last year released global guidance to improve diversity in trials.

In Europe, a consortium of 73 private and public organisations launched Research in Europe and Diversity Inclusion (READI) in January to tackle the under-representation.

British drugmaker GSK, which is part of READI, said the demand to conduct trials that are representative of the different populations and countries they work in remained high.

Pfizer and Moderna, makers of COVID vaccines, said they were committed to boosting diversity in clinical trials.

In January, Britain began consulting on how best to reflect diverse ethnicity, age, sex and gender in clinical research. Naho Yamazaki, who is spearheading the draft guidance at Britain's Health Research Authority, said it was crucial the guidance truly removes barriers and was not just a "tick box" exercise.

"Reducing health disparity requires far more than just equitable representation in clinical research. It's got to be a global effort ultimately. It's not a quick thing, but the momentum is here," Yamazaki said.