Lack of diversity in cancer drug clinical trials may exacerbate racial disparities in mortality rates

By Laurén A Doamekpor PhD, MPH and Diana Zuckerman PhD

Letter to the Editor, Cancer Epidemiology, July 2014

A study published in Cancer Epidemiology in April 2014 showed that between 1990 and 2009, the disparity in breast cancer mortality between Black and White women has widened in our country’s most populated states. Like most cancer experts, the authors (Ms. Hunt and her colleagues) conclude that although there have been advances in breast cancer screening, prevention and treatment, these advances have not been equally available to Black and White patients.1

In July 2014, Dr. Laurén Doamekpor and Dr. Diana Zuckerman of the National Center for Health Research published a response in the same journal, agreeing that access is a problem but pointing out that a lack of racial and ethnic diversity in clinical trials may exacerbate this disparity.2 Scientific knowledge gained from clinical trials on prevention and treatment is important; unfortunately, patients of color continue to be underrepresented in clinical trials that are submitted to the Food and Drug Administration (FDA) when a company applies for FDA approval.3  Since relatively few people of color are included in studies submitted to the FDA, and even fewer studies analyze and report safety and efficacy separately by race or ethnicity, it is unlikely that scientists will discover treatments that are safe and effective for minority patients if those patients metabolize certain drugs differently or tend to have different types of cancer, such as triple negative breast cancer. This contributes to racial disparities when treatments are not adequately tested for  safety or efficacy in these populations.

  1. Hunt BR, Whitman S, Hurlbert MS. Increasing Black:White disparities in breast cancer mortality in the 50 largest cities in the United States. Cancer Epidemiol 2014.  
  2. Doamekpor LA, Zuckerman DM. Lack of diversity in cancer drug clinical trials may exacerbate racial disparities in mortality rates. Cancer Epidemiol 2014.  
  3. Food and Drug Administration. FDA Report: Collection, Analysis, and Availability of Demographic Subgroup Data for FDA-Approved Medical Products, August 2013; 2014, Available at: Legislation/FederalFoodDrugandCosmeticActFDCAct/SignificantAmendmentstotheFDCAct/ FDASIA/UCM365544.pdf (accessed 31.03.14)