Johns Hopkins University Scientist Calls for More Attention to Gender Differences in Clinical Trials

Sabra L. Klein, an associate professor in the Bloomberg School of Public Health a Johns Hopkins University in Baltimore, is a leading expert on how males and females differ in their immune responses to viral infection and vaccination. In a recent report published in Hopkins Bloomberg Public Health, Dr. Klein argues that most researchers ignore gender differences when conducting research and clinical trials.

Dr. Klein states that “almost no one is paying attention to the fact that sex matters on a cellular level. The difference is manifest in our molecules — the very enzymes that metabolize the drugs we take, for instance. Mounting evidence from my lab and others around the globe reveals differences in men’s and women’s responses to pathogens as well as therapies, no matter whether we’re looking at Zika, malaria, flu, lupus, or heart disease.”

Dr. Klein notes that “despite studies showing that in women, a half dose of the flu vaccine is as effective as a full dose and may cause fewer adverse reactions, the FDA still recommends that men and women receive the same full dose annually. There should be sex-specific recommendations. But we’re never going to get those until we embark on studies with an a priori hypothesis reflecting that sex matters and until studies are designed appropriately to look at sex differences.”

Dr. Klein is a graduate of Randolph-Macon College in Ashland, Virginia. She holds two master’s degrees from the University of Georgia and a Ph.D. from Johns Hopkins University.