A new study in the US has found that less than 8% of oncology clinical trials over the past decade featured participants from the country’s major races.

The study was performed by the University of British Columbia, the Fred Hutchinson Cancer Center, the University of Texas MD Anderson Cancer Center, and Baylor University.

Data from cancer drug trials between 2008 and 2018, which comprised a total of 112,293 subjects across 230 studies, revealed a lack of racial and ethnic diversity.

Black and Hispanic patients were the most underrepresented at 22% and 44%, respectively, given the incidence of cancer in these populations.

Based on the study findings, researchers expressed concerns about the study drugs’ effectiveness in certain patients as therapeutic responses may be impacted by genetic differences.

University of British Columbia medical oncology assistant professor Dr Jonathan Loree said: “Our findings show that the science might not be applicable to the population that’s going to receive the medications.

“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.”

During the study, the population-based cancer estimates by race in the US were calculated with the National Cancer Institute and US Census data.

Though the study was specific to the US, researchers noted that the findings are also applicable to Canada.

Commonly, drug makers seek approval in the US first because the country is known to cater to the largest market. Companies then make regulatory submissions to the European Medicines Agency and Health Canada.

Researchers noted that the trials reviewed in the approvals are typically the same. The team is currently analysing gender in the clinical trials and general population.