Study Finds Lp-PLA2 is Reduced by About One-Third in Patients Receiving Lifestyle Intervention and Drug Therapy and that Changes in Lp-PLA2 are Only Slightly Related to Changes in LDL-C

SOUTH SAN FRANCISCO, Calif., June 16 /PRNewswire/ -- diaDexus, Inc., manufacturer of the PLAC(R) Test, today announced seven presentations involving lipoprotein-associated phospholipase A2 (Lp-PLA2), a novel inflammatory biomarker and independent predictor for cardiovascular disease, will be presented at the XV International Symposium on Atherosclerosis (ISA) convening June 14-17 in Boston, Mass.

Lead author of one of the studies, Kota Reddy, M.D., of Reddy Cardiac Wellness, Houston, Texas will present his research, "Effects of Lifestyle Intervention and Combination Lipid Modifying Therapy on Lipoprotein-Associated Phospholipase A2" today. The study involved 248 patients with mixed lipid disorders who often present with diabetes or metabolic syndrome. Over a period of 10.5 months, patients received a combination of lifestyle intervention including diet and exercise counseling, as well as multiple drug therapies such as omega-3 fish oil, extended release niacin and statins. Mean Lp-PLA2 values were reduced by 32.5 percent, demonstrating that Lp-PLA2, an established risk marker for heart disease, can be lowered through lifestyle changes and drug therapy. The study also examined the relationship between changes in Lp-PLA2 and LDL cholesterol (LDL-C) and found they were not strongly linked.

"The primary finding of the study is that Lp-PLA2, a specific marker of arterial plaque inflammation can be significantly reduced through the practice of lifestyle modification and drug therapy for patients at high risk," said Kota Reddy, M.D., lead researcher for the study. "Elevated Lp-PLA2 is a sign that there is an inflamed plaque in the artery that may be ready to crack. Perhaps even more significant is the finding that the mechanism of action that causes the reduction in Lp-PLA2 is different than the processes involved in reducing LDL-C. This finding may help lead to a better understanding of why statins reduce stroke risk, independent of changes in cholesterol levels."

The following research involving Lp-PLA2 will also be presented at the ISA on Tuesday, June 16:

• "Is Lipoprotein-Associated Phospholipase A2 in high density lipoprotein a risk factor for coronary vascular disease in the elderly," poster (#886), presented by M.J. Caslake, PhD.
• "The prevalence of elevated levels of inflammatory biomarkers Lp-PLA2 and hs-CRP among apparently healthy young adults," poster (#827), presented by Kota Reddy, M.D.
• "Association of Lp-PLA2 with coronary artery disease in African Americans and Caucasians," poster (#410), presented by Anuurad Erdembileg, M.D., PhD.
• "Low prevalence of elevated levels of Lipoprotein-Associated Phospholipase A2 mass observed among persons with increased levels of high density lipoprotein cholesterol," poster (#337), presented by Kota Reddy, M.D.
• "Novel inflammatory risk markers including Lp-PLA2 and risk of CHD in patients with familial hypercholesterolaemia (FH)," poster (#674), presented by M. Seed.
• "Do novel biomarkers correlate with preclinical atherosclerosis?" poster (#1189), presented by Andrzej Boguszewski, M.D.

About the PLAC(R) Test

The PLAC(R) Test is the only FDA-cleared blood test to aid in assessing risk for coronary heart disease and ischemic stroke associated with atherosclerosis. The simple blood test measures levels of a novel risk marker, lipoprotein-associated phospholipase A2 (Lp-PLA2), a vascular specific inflammatory enzyme implicated in the formation of rupture prone plaque; it is plaque rupture and thrombosis (major blood clot), not stenosis (narrowing of the arteries), that causes the vast majority of heart attacks. The PLAC Test is recommended for patients at moderate to high risk for heart attack or stroke, according to an expert panel consensus published in a June 2008 supplement to The American Journal of Cardiology.

About diaDexus

diaDexus, Inc., a privately held diagnostics company based in South San Francisco, is focused on the development and commercialization of patent-protected in vitro diagnostic products addressing unmet needs in cardiovascular disease. For more information, visit www.plactest.com or www.diaDexus.com.

SOURCE diaDexus, Inc.