While women are equally or overrepresented in clinical trials for hypertension, atrial fibrillation (AFib) and pulmonary arterial hypertension, they are underrepresented in clinical trials for heart failure, coronary artery disease and acute coronary syndrome, according to a new study in the Journal of the American College of Cardiology.
The researchers sought to compare the representation of women to the incidence or prevalence of women studied for each disease.
Led by Janet Woodcock, MD, of the FDA Center for Drug Evaluation and Research, the group of investigators reviewed the number of women and men who participated in cardiovascular trials submitted to the FDA that supported new drug application approvals.
In an almost 10.5-year period, there were 36 approvals for 35 drugs for conditions including acute coronary syndrome or myocardial infarction, AFib, coronary artery disease, heart failure, hypertension and pulmonary arterial hypertension.
The researchers calculated the participation of women by dividing the percentage of women among trial participants by the percentage of women with the disease.
The proportion of women enrolled ranged from 22 percent to 81 percent. The calculated participation to prevalence ratio disease area was within or above the desirable range for AFib at 0.8-1.1, hypertension at 0.9 and pulmonary arterial hypertension at 1.4—all within or above the desirable range.
The participation to prevalence ratio was 0.5 to 0.6 for heart failure, 0.6 for coronary artery disease and 0.6 for acute coronary syndrome/myocardial infarction.
“As we move into the era of precision medicine, that is, assessing the impact of a wide range of patient and disease characteristics on drug effects, it is imperative that clinical trial participants represent the full spectrum of patients for whom the drug will be prescribed,” Woodcock et al. wrote. “Clinical researchers, patient advocacy groups, federal agencies and industry must work together to ensure that representative patient populations are enrolled. These steps will move us closer toward the goal of providing the best information possible about the use of drugs for every patient.
The researchers also assessed the gender differences in efficacy or safety but found little indication of clinically meaningful gender differences for either factor. Gender differences in efficacy or safety were described in labeling for four drugs.
“Based on this work, future research is needed to identify factors leading to under participation of women in cardiovascular clinical trials, particularly those occurring before screening,” the authors concluded. “Research is needed to better define barriers that limit participation of diverse populations, not only of women, but also of minorities and the aged. Although some have postulated that inclusion/exclusion criteria have led to under-participation of women in cardiovascular trials, we did not find evidence to support this concept.”
As a senior news writer for TriMed, Subrata covers cardiology, clinical innovation and healthcare business. She has a master’s degree in communication management and 12 years of experience in journalism and public relations.