Hopkins pharmacologist calls for diversifying clinical trials

As the pandemic looms on, social justice advocates are urging more pharmaceutical companies to consider race and ethnicity when developing and testing drugs. One of these advocates is Namandje Bumpus, director of the Department of Pharmacology and Molecular Sciences at the School of Medicine.

“Human beings are genetically similar, and we are largely the same, but there are differences in how we process things like drugs and things that we are exposed to in the environment,” she said in an interview with The News-Letter.

Last year Bumpus broke the color barrier by becoming the first African American woman appointed to her position. Additionally, she is the only African American woman chairing a department of pharmacology at any medical school in the United States. Bumpus acknowledged that her achievements were no easy feat.

“I got a lot of discouragement in high school,” Bumpus said. “I had teachers always telling me that I was a black girl, and I was never going to be able to do it. I had a high school math teacher who laughed at me when I was talking about going to college. He said, ‘Black girls don’t go to college.’”

But Bumpus persevered. Today she uses her passion for racial equity as fuel to motivate change in the world of medicine. In an interview with The News-Letter, Bumpus detailed how she uses her platform to advocate medicinal justice for minorities.

“When I am in bigger teams and scientific groups, I feel responsible for raising the topic of how medicine may affect different racial groups and communities,” she said. “There are some people who culturally might not want certain medicines versus other people.

According to a recent poll from the Kaiser Family Foundation, one-third of Black adults in the U.S. said they don’t plan to get vaccinated, citing safety concerns and newness of the vaccine as the main deterring factors. According to Kaiser Health News, Black workers were 44% less likely to get the vaccine than their white counterparts while Latino workers were 22% less likely.

While this issue may be problematic, Americans must be understanding of the racism that has caused minorities to distrust medicine. According to Namandje, exclusion of minorities in clinical trials is one of the biggest issues when it comes to medicine.

A drug’s safety, side effects and safe dosage range are all determined by clinical trials. Yet, as Bumpus wrote in a recently published article, minorities are often neglected as subjects for clinical trials. As a result, dosage recommendations are largely based on trials with individuals of European backgrounds. 

She noted that this lack of diversity is a problem because the speed of drug metabolism can vary based on genetic variations; as a result, people can be categorized into poor, intermediate, extensive or ultrarapid metabolizers of certain drugs. This is particularly the case for prodrugs, which are drugs that are pharmacologically inactive when administered but become active when they are metabolized by the body. Depending on a person’s rate of drug metabolism, a certain dose can lead to toxic accumulation or may be insufficient to be effective.

“Well-designed trials, including those for COVID-19 therapeutics, need to be powered in such a way that they can characterize potential genetic differences in clinical outcomes that may be specific to certain ethnic groups,” Bumpus wrote in her article. “This means that clinical trials must reflect the population, and in diseases where ethnic disparities in incidence and/or mortality have been established, consideration should be given to making commensurate adjustments in clinical trial demographics.”

While genetic variations between racial groups may not always significantly affect the efficacy of a certain drug, Bumpus wrote that diversifying clinical trials will allow researchers to catch instances when they do. She described the example of cytochrome P450, which is a major player in the drug metabolism pathway. While 90% of individuals of European descent have a certain variant of cytochrome P450, most people of African American descent are CYP3A5 expressors because they have a different variant of cytochrome P450. 

A study that evaluated the effects of tacrolimus, a drug that is used to prevent solid organ transplant rejection, found that CYP3A5 expression is associated with lower blood concentrations of tacrolimus. This in turn means that those patients require greater doses of tacrolimus for it to be effective.

In her article, Bumpus calls for researchers to be transparent about the racial and ethnic makeup of their clinical trials. Funding agencies, she wrote, should hold researchers accountable and research institutions should recruit a more diverse workforce. 

While there is much work that needs to be done, Bumpus remains hopeful and optimistic about the improvement of diversity, equity and inclusion in science.

“Awareness is really increasing around the need to think about diversity in science and opportunities are opening up,” she said. “We are seeing more interest and urgency around the cause for greater inclusivity.”