[13N]Ammonia ([13N]NH3) is a useful 13N-labeled compound that has been developed as a positron emission tomography (PET) imaging agent for assessing regional blood flow in tissues. It is indicated for diagnostic PET imaging of the myocardium under rest or pharmacologic stress conditions to evaluate myocardial perfusion in patients with suspected or existing coronary artery disease. No adverse reactions have been reported for Ammonia N 13 Injection based on a review of the published literature, publicly available reference sources, and adverse drug reaction reporting systems. The possibility of interactions of Ammonia N 13 Injection with other drugs taken by patients undergoing PET imaging has not been studied.

Fludeoxyglucose F-18 is a positron emitting radiopharmaceutical that is used for diagnostic purposes in conjunction with positron emission tomography (PET) imaging.

Ticlopidine (trade name Ticlid) is an antiplatelet drug in the thienopyridine family which is an adenosine diphosphate (ADP) receptor inhibitor. Ticlopidine is a prodrug that is metabolized to an as yet undetermined metabolite that acts as a platelet aggregation inhibitor. Inhibition of platelet aggregation causes a prolongation of bleeding time. In its prodrug form, ticlopidine has no significance in vitro activity at the concentrations attained in vivo. The active metabolite of ticlopidine prevents binding of adenosine diphosphate (ADP) to its platelet receptor, impairing the ADP-mediated activation of the glycoprotein GPIIb/IIIa complex. It is proposed that the inhibition involves a defect in the mobilization from the storage sites of the platelet granules to the outer membrane. No direct interference occurs with the GPIIb/IIIa receptor. As the glycoprotein GPIIb/IIIa complex is the major receptor for fibrinogen, its impaired activation prevents fibrinogen binding to platelets and inhibits platelet aggregation. Ticlopidine is FDA approved for the prevention of strokes and, when combined with aspirin, for patients with a new coronary stent to prevent closure. There are also several off-label uses, including acute treatment of myocardial infarction and unstable angina, peripheral vascular disease, prevention of myocardial infarctions, diabetic retinopathy, and sickle cell disease. The most serious side effects associated with ticlopidine are those that affect the blood cells, although these life-threatening complications are relatively rare.

Rubidium Rb-82 is a radioactive isotope of rubidium. It is widely used for Positron Emission Tomography (PET) imaging of the myocardium under rest or pharmacologic stress conditions to evaluate regional myocardial perfusion in adult patients with suspected or existing coronary artery disease. Rb-82 decays by positron emission and associated gamma emission with a physical half-life of 75 seconds. In biochemical behavior, it is analogous to potassium ion (K+) and is rapidly extracted by the myocardium proportional to the blood flow. Rb+ participates in the sodium-potassium (Na+/K+) ion exchange pumps that are present in cell membranes. 82 radioactivity in viable myocardium is higher than in infarcted tissue, reflecting intracellular retention. Rubidium 82 chloride was approved by the FDA and is marketed under a trade name Ruby-Fill and Cardiogen-82.

Amlodipine is a dihydropyridine calcium antagonist (calcium ion antagonist or slow-channel blocker) that inhibits the transmembrane influx of calcium ions into vascular smooth muscle and cardiac muscle. Experimental data suggest that amlodipine binds to both dihydropyridine and nondihydropyridine binding sites. The contractile processes of cardiac muscle and vascular smooth muscle are dependent upon the movement of extracellular calcium ions into these cells through specific ion channels. Amlodipine inhibits calcium ion influx across cell membranes selectively, with a greater effect on vascular mooth muscle cells than on cardiac muscle cells. Amlodipine is indicated for the treatment of hypertension and coronary artery disease.

Apabetalone (RVX-208) is a small molecule BET bromodomain inhibitor selective for BRD4-BD2 undergoing clinical development as a potential therapy to enhance ApoA-I production and treat atherosclerosis and prevent cardiovascular disease events. Apabetalone increases apolipoprotein A-I and high-density lipoprotein cholesterol (HDL-Cholesterol) in vitro and in vivo which is believed to provide a new approach to treating atherosclerosis through the stimulation of reverse cholesterol transport. RVX-208 increased the Tm of all BET bromodomains, indicative of binding. RVX-208 competes for acetylated histone H4 peptide binding to both bromodomains of BRD4, similar to JQ-1, but with a preference for BD2 over BD1. RVX-208 also binds to the bromodomains of BRDs 2 and 3 with a similar preference for BD2 (Kd~5–30 nM) over BD1 (Kd~2–3 uM). Treatment of humans for 1 week with oral RVX-208 increased apoA-I, pre-beta-HDL, and HDL functionality. Resverlogix Corp. has commenced a Phase 3 clinical trial in cardiovascular disease patients with type 2 diabetes mellitus with a primary endpoint of time to first occurrence of Major Adverse Cardiac Events (MACE).

Atopaxar, also known as E 5555 is a novel reversible protease-activated receptor-1 (PAR-1) thrombin receptor antagonist. The inhibition of thrombin-mediated platelet activation by means of protease-activated receptor-1 inhibitors represents an attractive therapeutic option for patients with atherothrombotic disease processes. In preclinical studies, atopaxar demonstrated inhibition of thrombin receptor-activating peptides (TRAP)- and thrombin-induced platelet aggregation. Atopaxar was being developed by Eisai for acute coronary syndromes (ACS) and coronary disorders, including atherothrombosis, unstable angina pectoris and myocardial infarction. Atopaxar was in phase II clinical development in the US, EU and Japan. However, development was discontinued in May 2012.

Terutroban (S18886), a specific thromboxane A2 receptor antagonist, which improves endothelial function and has an antiatherosclerotic effect. The compound is under development by Servier for the potential treatment of cardiovascular diseases and coronary artery disease. In addition, it participated in phase III clinical trials PERFORM (Prevention of cerebrovascular and cardiovascular Events of ischemic origin with teRutroban in patients with a history oF ischemic strOke or tRansient ischeMic attack), but this study was stopped, and the result was not achieved.

Varespladib (LY315920; A-001) is a potent and selective inhibitor of IIa, V, and X isoforms of human non-pancreatic secretory phospholipase A2 with nM IC50. The molecule acts as an anti-inflammatory agent by disrupting the first step of the arachidonic acid pathway of inflammation. Varespladib methyl is being developed by Anthera Pharmaceuticals Inc for the potential treatment of coronary artery disease, acute coronary syndrome and inflammation. Varespladib methyl is a prodrug that is rapidly metabolized to varespladib, and both compounds are able to potently inhibit the enzymes of the human secretory phospholipase groups. Phase II clinical trials of varespladib methyl in patients with coronary artery disease, rheumatoid arthritis, asthma and ulcerative colitis revealed that the drug was well tolerated. Varespladib methyl did not demonstrate a good efficacy profile in patients with rheumatoid arthritis, asthma and ulcerative colitis; whereas in patients with coronary artery disease, varespladib methyl consistently reduced LDL-cholesterol levels, (elevated LDL-cholesterol levels are a marker of increased cardiovascular risk). Varespladib methyl could represent a novel therapy for the treatment of cardiovascular disease, although the efficacy, safety profile and advantages of this drug compared with existing therapeutic options would need to be established in upcoming phase III trials.

Darusentan is an orally active, propanoic acid-based endothelin receptor antagonist (ERA) that selectively blocks endothelin-1 (ET-1) binding to the endothelin type-A (ETA) receptor. Darusentan exhibited subnanomolar binding affinity and approximately 1000-fold selectivity for the ETA receptor in binding experiments conducted in vitro under steady-state conditions. Darusentan is orally bioavailable and, when administered to humans, maximum plasma concentrations are observed within 1–2 h post dosing. The mean elimination half-life is relatively long (>15 h), which is consistent with once-daily dosing. Darusentan is primarily glucuronidated by Phase II enzymes in the liver, and the major route of elimination of Darusentan and its metabolites is via the bile. Some glucuronidated metabolites of Darusentan are also excreted in the urine. Darusentan doses up to 300 mg/day were well tolerated and associated with a manageable safety profile in patients with resistant hypertension (RHTN). The most frequently reported adverse events in Ddarusentan-treated subjects were peripheral edema (17%) and headache (11%), which were mostly mild or moderate in severity. Other commonly reported adverse events in the Darusentan treatment group were sinusitis (8%), dizziness (7%), upper respiratory tract infection (5%) and gastroenteritis (5%). In phase III clinical trial the mean reductions in clinic systolic and diastolic blood pressures were 9/5 mm Hg with placebo, 17/10 mm Hg with Darusentan 50 mg, 18/10 mm Hg with Darusentan 100 mg, and 18/11 mm Hg with Darusentan 300 mg. Unfortunately, phase III clinical trial evaluating Darusentan did not achieve its co-primary efficacy endpoints of achieving a change in systolic and diastolic blood pressure after 14 weeks compared to a placebo. Perhaps for this reason, shortly after the top-line results of this study became known, the sponsor announced that Darusentan would not be developed further for resistant hypertension.