A newly released study published in JAMA Oncology is raising concerns about the lack of racial diversity in clinical trials on cancer drugs analyzed by the U.S. Food and Drug Administration (FDA).
As a result, the study warns that differences in genetic makeup that can affect how certain racial populations respond to a drug might not be accounted for.
The researchers in the study—from UBC in Vancouver, the Baylor University in Texas, the University of Texas MD Anderson Cancer Center, and the Fred Hutchinson Cancer Center in Seattle—looked at 230 drug trials featuring a total of 112,293 participants. These trials took place from July 2008 to June 2018.
When looking at the amounts of racialized individuals in these studies, they discovered black and Hispanic populations were being underrepresented in proportion to the share of people diagnosed with cancer who are black or Hispanic.
The proportion of black patients in these studies was only 22 percent of the share of cancer patients who are black. This share is 44 percent for Hispanics.
In contrast, Asian individuals are over-represented in these studies. Although the proportion of Asian cancer patients is quite small, they are over-represented in these studies by 438 percent.
The share of white people in these studies is 98 percent proportional to the amount of cancer patients who are white.
Due to differences in genetic make-up, drugs can have a different effect on different racial populations. UBC medicine assistant professor Dr. Jonathan Loree noted the example of a lung-cancer medication that had strong results among Asian women who had never smoked, but weaker results within the general population.
“Our findings show that the science might not be applicable to the population that’s going to receive the medications,” he said in a media release. “If patients are going to be receiving the drug, we need to know that it’s going to work for them with the same effectiveness that’s seen in the trial.”
Furthermore, documentation of race in these studies is small: only eight percent of them reported testing white, Asian, black, and Hispanic patients all at once.
63 percent of the studies mentioned at least one race when reporting on their patients. White people were reported in 62.6 percent of the studies, while Asian and black patients were reported in 47.5 percent and 47.8 percent of them, respectively.
Hispanics were only reported in 10 percent of all trials.
Lorne notes in the press release that although the statistics looked at American studies, they’re also applicable to Canada since most cancer drugs get approval from the FDA first. However, they weren’t able to analyze Indigenous people in the study because there were only 13 individuals among over 112,000 participants who were Indigenous.