Stanford researchers testing ways to improve clinical trial diversity

The American Heart Association has provided funding to two Stanford Medicine professors to develop ways to diversify enrollment in heart disease clinical trials.

- By Jennifer Welsh

Hannah Valantine

Two Stanford Medicine professors are working with the Morehouse School of Medicine to test ways to enroll more diverse patients in clinical trials for heart disease treatments. The research is part of a $20 million project launched by the American Heart Association to improve diversity in clinical trials.

“Many common chronic diseases disproportionately affect communities of color,” said Hannah Valantine, MD, a professor of cardiovascular medicine at Stanford Medicine. For example, Black Americans are 30% more likely to die of heart disease than white Americans, according to 2018 data from the U.S. Health and Human Services. “To translate research discoveries into medicines that can make an impact on those communities, we must have diversity in the clinical trials testing them,” she noted.

Valantine and Eldrin Lewis, MD, a professor of cardiovascular medicine and the Simon H. Stertzer, MD, Professor III, will each lead an experimental program. Together, Stanford and Morehouse will receive $4.8 million of this funding — $500,000 for Valantine’s project and $4.3 million for Lewis’.

Clinical trials often do not adequately represent the demographics of the U.S. population: A study of trials between 2006 and 2020 for Food and Drug Administration-approved cardiovascular medications found that less than 3% of participants were Black, although African Americans make up 12.4% of the U.S. population, according to the 2020 census.

The lack of diversity doesn’t just apply to Black patients. Native Hawaiian, Pacific Islander, Filipino and Latin American communities, for example, are also underrepresented in cardiovascular clinical trials. Other AHA grantees are conducting programs to increase participation by these groups in clinical trials.

“For decades, there have been efforts to increase the diversity of clinical trial participants,” said Lewis, chief of the division of cardiovascular medicine. “But despite these efforts, we’ve not moved the needle at all.”

Eldrin Lewis

Overcoming racism and bias

Valantine will lead the Training Researchers to Advance Inclusion Networks (TRAIN) program, which will train a dozen cardiovascular fellows interested in clinical trials on how systemic racism, individual racism and racial bias reduce the participation of non-white patients.

“These same groups of patients who must be included in clinical trials have suffered the brunt of misuse of research — so there is mistrust,” said Valantine, referring to the Tuskegee syphilis study and Henrietta Lacks. “The individual scientist-researcher who’s going to run clinical trials must be aware of these pressures to be ready and equipped to overcome them.”

The program will also teach fellows to engage with diverse communities and lead educational modules to train their colleagues involved in clinical trials. The researchers are hoping to track the effects of this training on the diversity of the clinical trials their fellows are managing. In addition, the TRAIN team plans to roll out the curriculum to the entire network of AHA-funded institutions.

Advancing inclusion efforts

Lewis will lead the Diversity and Inclusion in Cardiovascular through Enrollment and Education Resulting in Sustainable Equity (DIVERSE) network to determine if specific interventions can improve the participation of Black patients as a primary goal. The first arm of the study tests six strategies — including free transportation, artificial intelligence programs to find eligible patients and community outreach.

The DIVERSE network will randomly roll out these interventions nationwide in 112 cardiovascular clinical trials. As a secondary goal of the study, the researchers will analyze the data to determine if the interventions affected other marginalized groups, such as other underrepresented minorities, patients over 65, women, LGBTQ+ participants and those with significant disabilities.

“No one has systematically studied whether any of these methods are effective,” Lewis said. ‘We’ve historically just said, ‘Let’s try it.’ So, we want to answer the question ‘Does it work?’”

In addition to studying interventions, the DIVERSE researchers will work with doctors to understand what prevents their patients from participating in clinical trials. They’ll also seek ways to remove these barriers. The team will compile what they learned from these efforts into an open-access toolkit for community doctors and hospitals.

The fellows participating in the TRAIN curriculum will also be working on the clinical trials implementing the DIVERSE studies’ interventions. They’ll be able to see the effects of these interventions in action and apply their learnings from the program directly to these trials.

“We hope to show that integrated approaches, which involve training on one hand and Dr. Lewis’ interventions on the other, are increasing the diversity of clinical trials,” Valantine said.

The AHA program on the science of diversity in clinical trials was funded with the help of Pfizer and Gates Ventures. The grants support teams of scientists from 11 universities and health care systems. The projects began April 1, 2022, and will continue for four years.

About Stanford Medicine

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