Women, Asian and Black participants underrepresented in COVID-19 clinical trials, researchers find

Women, Asian and Black participants were underrepresented in more than 100 clinical trials for COVID-19 drugs and vaccines, a new analysis has found.

Meanwhile, Hispanic and Latino participants were overrepresented, according to the study published Monday in JAMA Internal Medicine. The researchers looked at 122 U.S.-based trials for COVID-19 that were conducted with more than 176,000 participants, including meds for both prevention and treatment of the disease caused by the SARS-CoV-2 virus. The data is from studies that actually included demographic info conducted from October 2019 to February 2022.

Women made up 48.9% of the population of prevention trials and 44.6% of studied treatments. This contrasts with a representation of 52.4% for the total U.S. population. Women had better participation in prevention trials compared to the actual COVID-19 population, but were underrepresented in treatment studies.

The U.S. population is 14.1% Black, and yet the trials included just 7.2% and 16.5% of those participants. Black participants were better represented in treatment trials than prevention studies. This may be because treatment studies were conducted in patients who sought treatment for COVID-19. So Black participants may have been more willing to sign on while hospitalized or sick with the disease already than seek to participate in a study for a preventive treatment or vaccine, the researchers suggested.

For Asian participants, the rate was 3.8% and 4.6% for prevention and treatments, respectively, compared with 3.7% for the total U.S. population.

While the last one may seem like an overrepresentation, the researchers also compared the populations with the expected rate of COVID-19 infection. For all the above populations, the trials were not representative of the disease burden.

Hispanic or Latinos make up 17.7% of the U.S. population, and yet they were 23% and 36.6% of the population for prevention and treatment trials, respectively. This is at odds with previous research that found this population is typically underrepresented.

The researchers said the overrepresentation was because a third of all trial sites were in California, Florida and Texas, which have large Hispanic or Latino populations. But there also may be a gap in the data for COVID-19 rates in this population as well.

“These findings highlight the ongoing struggle in the U.S. to provide equitable access to clinical studies regardless of an individual’s demographic background,” the study said.

So how did the pharmaceutical industry get the balance so wrong? Well the research, supported by the Fred Hutchinson Cancer Center in Seattle, noted that calls have been made since the start of the pandemic to ensure diversity in the clinical trials used to support COVID therapeutics and vaccines.

The lack of representation in clinical trials as a whole has been well documented, according to the researchers. But the problem was heightened with the rush to develop treatments to stem the deaths and illness that spread quickly around the world in the first two years of the pandemic.

Without underrepresented populations in clinical trials, data from studies can not be confidently applied to the broader population, the researchers said.

Federally-funded studies did better than those sponsored by industry, as well. Industry trials are not subject to National Institutes of Health guidelines for proportional racial representation. The majority of COVID-19 trials are conducted by industry, the researchers said. And industry is responsible for the majority of production, marketing, and distribution of therapeutics and preventatives, meaning the poor representation “has unique implications for disparities in treatment efficacy, adverse effects, and access.”

Industry could be spurred to action with tax breaks and patent protections for including a more diverse population in their studies, the researchers noted.

Patients could be better included if financial barriers to participation were removed, such as getting rid of co-pays and co-insurance. Support for things like transporation, childcare and time off work to participate could also help.

Black participants also need to see healthcare providers who look like them to feel comfortable participating, given the history of racism in the community. For Asian populations, providing healthcare professionals familiar with native languages could help drive interest in studies.

The researchers also noted that data on demographics, sex, race and ethnicity were hard to come by. When this information was reported, 20% of studies did not meet the NIH recommendations to report race and ethnicity as independent categories.