December 17, 2014 — The U.S. Food and Drug Administration (FDA) cleared a new screening test that predicts a patient’s risk of future coronary heart disease (CHD) events, such as heart attacks.
The PLAC Test for Lp-PLA2 Activity measures the activity of lipoprotein-associated phospholipase A2 (Lp-PLA2) in a patient’s blood. Lp-PLA2is a biological marker for vascular inflammation, a condition associated with the buildup of plaque in the arteries that supply blood to the heart. Over time, this buildup can result in a narrowing of the arteries and lead to CHD. Patients with test results that show Lp-PLA2activity greater than the level of 225 nanomoles per minute per milliliter (nmol/min/mL) are at increased risk for a CHD event. Patients with test results below this level are at decreased risk for a CHD event.
FDA cleared the test for use in all adults with no history of heart disease, but studies submitted by manufacturer diaDexus Inc. and reviewed by the FDA show the test is better at discerning this risk in women, particularly black women.
“A cardiac test that helps better predict future CHD risk in women, and especially black women, may help health care professionals identify these patients before they experience a serious CHD event, like a heart attack,” said Alberto Gutierrez, director of the office of in vitro diagnostics and radiological health in the FDA’s Center for Devices and Radiological Health. “We hope the clearance of this test will improve preventative care and reduce CHD-related mortality and morbidity in these patients.”
The FDA’s review included the PLAC Test for Lp-PLA2 Activity study, a sub-study from the National Institutes of Health’s national Reasons for Geographic and Racial Differences in Stroke study that targeted a balanced enrollment of gender and race.
In the PLAC Test for Lp-PLA2 Activity validation study, researchers performed the test on 4,598 participants ranging in age from 45 to 92 with no history of CHD. The participants included 41.7 percent men and 58.3 percent women, and 41.5 percent blacks and 58.5 percent whites.
Researchers followed the participants over the course of several years and recorded who experienced a CHD-related event. The median follow-up time was 5.3 years. The study showed that participants with test results higher than 225 nmol/min/mL had a CHD event rate of 7 percent, while patients with test results below that level had a CHD event rate of 3.3 percent.
The FDA requested data analyses of additional subgroups, including black women, which showed that black women experienced a higher jump in the rate of CHD events compared to other participants when Lp-PLA2 levels were higher than 225 nmol/min/mL. As a result, the test’s labeling contains separate performance data for black women, black men, white women and white men.
For more information: www.plactest.com