Clinical Trials

In April 2008, a coronary catheter based imaging system, LipiScan, was cleared by the FDA for use in detecting lipid core containing containing plaques of interest (LCP). These plaques are rich in cholesterol. The way that cholesterol and other lipids deposit with the coronary artery is unique to each patient. This study is an organized attempt to observe the LCP and the variety of ways that it presents in patients as detected by this recently approved device. This information will be used for physician training and to observe the behavior of the LCP in response to no therapy and currently approved therapies. The purpose of this project is further medical knowledge of the LCP and its treatment.

Aim I: Hypothesis: The extent of endothelial dysfunction will correlate with production of Lp-PLA2 and oxidative stress and correlates with the tissue characteristics of plaque vulnerability. The investigators will define the systemic and coronary gradient and production of markers of inflammation and oxidative stress and the presence of coronary endothelial dysfunction in patients with early coronary atherosclerosis. Aim II: Hypothesis: The distribution of Lp-PLA2 on the LDL is associated with greater coronary endothelial dysfunction and correlates with the degree coronary atherosclerosis and plaque vulnerability. The investigators will define the distribution of Lp-PLA2 in patients with early coronary atherosclerosis and endothelial dysfunction.

The main goal of AIM III is to assess and quantify the effect of long-term administration of darapladib 160 mg once a day, a selective, reversible, orally active inhibitor of plasma and vascular Lp-PLA2, on coronary endothelial function, progression of coronary atherosclerosis as determined by IVUS, and atherosclerosis in patients with early atherosclerosis. Patients with evidence of coronary endothelial dysfunction, as determined by intracoronary administration of acetylcholine during angiography and IVUS, will be followed for 6 months during once daily dosing of darapladib. Coronary endothelial function is determined by the changes in coronary artery diameter and coronary blood flow response to the intracoronary administration of acetylcholine and adenosine. The patients will be followed in clinic 6 months. They will have follow-up angiography, assessment of endothelial function, and IVUS during the six month visit.

The present study will be a substudy of our National Institute of Health (NIH) funded and Institutional Review Board (IRB) approved (08-008161) protocol "Lp-PLA2 and Coronary Atherosclerosis in Humans" and (10-000044) "Lp-PLA2 and Coronary Atherosclerosis in Humans AIM III" in which the investigators are examining the impact of long-term inhibition of Lp-PLA2, with a specific novel inhibitor, on LpPLA2 activity and improvement in coronary endothelial function.

     This substudy will use Optical Coherence Tomography (OCT) to quantify alternate features of plaque vulnerability including superficial microcalcification, fibrous cap thickness, and plaque macrophage content at baseline and again at 6 month following Lp-PLA2 inhibition.

     The study will provide insight into the role of the endogenous Lp-PLA2 in early coronary atherosclerosis, a potential therapeutic target for early coronary atherosclerosis in humans.

The present study will be a substudy of our National Institute of Health (NIH) funded and IRB approved (08-008161) protocol "Lp-PLA2 and Coronary Atherosclerosis in Humans" and (10-000044) "Lp-PLA2 and Coronary Atherosclerosis in Humans AIM III" in which the investigators are examining the impact of long-term inhibition of Lp-PLA2, with a specific novel inhibitor, on LpPLA2 activity and improvement in coronary endothelial function. The substudy will allow the investigators to also examine the additional endpoint of lipid core content of atherosclerotic plaques and hence plaque vulnerability. Plaque lipid composition will be measured using the LipiScan or LipiScan IVUS catheter (InfraReDx NIRS System with or without IVUS capability) at baseline and again at 6 month following Lp-PLA2 inhibition. The study will provide insight into the role of the endogenous Lp-PLA2 in early coronary atherosclerosis, a potential therapeutic target for early coronary atherosclerosis in humans.

The primary objective of this trial is to assess the effects of Bendavia on renal blood flow and renal function in atherosclerotic renal artery stenosis (ARAS), compared with placebo in patients with ARAS who receive one dose of study drug infused 30 minutes before and 3 hours after percutaneous transluminal angioplasty of the renal artery (PTRA).