- Clinical trials of COVID-19 vaccines need to include a diverse study population, including older adults, people with underlying health problems, and minorities.
- Some health experts have raised concerns that in the rush to develop a safe and effective vaccine, inclusion of minorities might get lost in the shuffle.
- Black and Latino people in the United States have been nearly twice as likely to die from COVID-19 as white people.
At least six candidate COVID-19 vaccines have entered phase III clinical trials. These large-scale tests will enroll tens of thousands of people in order to show whether the vaccines are safe and can protect people from the virus that causes COVID-19.
Researchers are also aiming to enroll a wider range of people in these studies, including older adults and people with other health conditions such as heart disease and diabetes.
Other health experts are calling for greater inclusion of racial and ethnic minorities, something that has not always been done with past research.
“It is essential that the vaccine trials include minorities, for the very simple reason that COVID-19 is a much more serious condition for African Americans and Latinos,” said Marjorie Speers, PhD, executive director of Clinical Research Pathways, a nonprofit group in Atlanta that works to increase diversity in research. “Those two groups of minorities suffer more than any other group in our population.”
Greater diversity in vaccine trials needed
Earlier this year, the New York Times sued the Centers for Disease Control and Prevention (CDC) to obtain racial and ethnic data on COVID-19. Its investigation found that Black and Latino people have been nearly twice as likely to die from COVID-19 as white people.
“The only way we’re going to know if a vaccine is safe and effective for [African Americans and Latinos] is if they are included in the vaccine trials,” said Speers.
Historically, however, these groups have been less likely to be included in clinical trials, in spite of the National Institutes of Health and Food and Drug Administration (FDA) both having guidelines calling for their inclusion.
For example, African Americans make up only 5 percent of participants in U.S. clinical trials, while they represent 13.3 percent of the country’s general population. Hispanics are also underrepresented in clinical trials for new treatments.
Dr. Kathryn M. Edwards, a professor of pediatrics and scientific director of the Vanderbilt Vaccine Research Program points out that the earlier COVID-19 vaccine trials have had limited racial diversity.
In the Oxford University/AstraZeneca phase I and II clinical trial published last week, over 90 percent of the 1,077 healthy volunteers were white. A similar lack of diversity was found in the Moderna phase I trial and Pfizer and BioNTech’s phase I and II study.
These trials tend to be smaller, so researchers may not put as much emphasis on ensuring that the study is racially and ethnically diverse.
But the much larger phase III trials will give groups developing COVID-19 vaccines the opportunity to include a wider range of people in their studies.
“In phase III trials, we certainly like to have a study population that looks like the overall population that we’re going to give the vaccine to,” said Edwards. “So we really would like to enroll people of different racial and gender and ethnic backgrounds.”
Speers says that everyone involved in these trials — from researchers running the study sites to pharmaceutical companies writing the protocols to the FDA — need to be more proactive in making sure that minorities are appropriately represented in the phase III trials.
Healthline reached out by email to Oxford University, Moderna, and Pfizer to ask how they would ensure that their phase III trials included more diverse populations, but did not receive a response by the time of publication.
However, Edwards says some of the researchers running the COVID-19 vaccine study sites are well positioned to recruit minorities.
“Some of the investigators on the phase III trials have been working on HIV treatment and prevention protocols, and have worked with a number of community groups in those initiatives,” she said.
Other health experts have raised concerns that in the rush to develop a safe and effective vaccine, inclusion of minorities might get lost in the shuffle.
“We can’t ignore the health disparities that currently exists for African Americans and Latinos,” said Speers. “So we don’t want to rush the development of these vaccines, and end up creating a greater health disparity because we don’t know if the vaccine works in African American and Latino populations.”
Dr. Bruce Y. Lee, executive director of PHICOR and professor of health policy management at CUNY Graduate School of Public Health and Health Policy, says that having diverse participation in vaccine trials also helps get communities on board with being vaccinated later on if one is approved by the FDA.
“People who volunteer for these studies have a better sense of what was done during these studies,” he said. “And they can relay this back to their community, saying that everything was properly done.”
Including older adults and people with health conditions
COVID-19 vaccine trials will also need to include more older adults and people with underlying health conditions. Both of these groups are at higher risk of a severe form of COVID-19.
Including these groups in later-stage trials is the only way to know if the vaccine is safe and effective for them.
“We’ve seen with other vaccines that the amount of protection that’s offered after giving a vaccine is dependent on the immune system’s response,” said Lee.
“For example, we know that older adults may have weaker immune responses,” he said. “The same thing is true for those taking medications that suppress their immune system.”
A phase II trial by Chinese researchers supported by CanSino Biologics included healthy adults up to 83 years. Moderna’s phase I trial also included older adults, but that data hasn’t been published yet.
Going forward, the Oxford and Moderna phase III trials will both recruit older adults, as well as people with certain underlying health conditions — as long as their disease is well controlled, according to information about the trials published on ClinicalTrials.gov. Pfizer also plans to recruit older adults.
So far, none of the currently active phase III trials will include children or pregnant women.
Edwards says it will be necessary to test the vaccine in those populations before the vaccine can be used widely in them. She says these studies, though, are still in the planning stage.
Overall, a more diverse study population will help ensure that a vaccine — if it’s found to be safe and effective — will work for everyone in the country.
“It would really be wonderful if we could have as much diversity in our vaccine studies as we can,” said Edwards. “I would certainly encourage people of all racial, gender, and ethnic backgrounds to sign up to be part of the studies.”
If you’re interested in taking part in a clinical trial for COVID-19 vaccines or treatments, check out the COVID-19 Prevention Network’s listing of studies now recruiting.