Sacubitril is a prodrug neprilysin inhibitor used in combination with valsartan (sold under the brand name Entresto among others) to reduce the risk of cardiovascular events in patients with chronic heart failure (NYHA Class II-IV) and reduced ejection fraction. It was approved under the FDA's priority review process for use in heart failure on July 7, 2015. Sacubitril's active metabolite, LBQ657 inhibits neprilysin, a neutral endopeptidase that would typically cleave natiuretic peptides such as atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and c-type natriuretic peptide (CNP). ANP and BNP are released under atrial and ventricle stress, which activate downstream receptors leading to vasodilation, natriuresis and diuresis. Under normal conditions, neprilysin breaks down other vasodilating peptides and also vasoconstrictors such as angiotensin I and II, endothelin-1 and peptide amyloid beta-protein. Inhibition of neprilysin therefore leads to reduced breakdown and increased concentration of endogenous natriuretic peptides in addition to increased levels of vasoconstricting hormones such as angiotensin II.

TAK-536 (generic name: azilsartan) is an angiotensin II type 1 receptor blocker, discovered by Takeda and its mechanism of action is to lower blood pressure by inhibiting action of a vasopressor hormone Angiotensin II. Angiotensin II type 1 receptor antagonists have become an important drug class in the treatment of hypertension and heart failure. TAK-536 is in phase III clinical trial for treatment hypertension. This drug also known as active metabolite of the prodrug azilsartan medoxomil (also known as azilsartan kamedoxomil), but in some countries azilsartan rather than its prodrug is used for oral treatment.

Regadenoson (Lexiscan), a low affinity agonist of the A2A adenosine receptor, increases coronary blood flow (CBF) and mimics the increase in CBF caused by exercise. Myocardial uptake of the radiopharmaceutical is proportional to CBF creating the contrast required to identify stenotic coronary arteries. It is a pharmacologic stress agent indicated for radionuclide myocardial perfusion imaging (MPI) in patients unable to undergo adequate exercise stress. The most common adverse reactions to Lexiscan are dyspnea, headache, flushing, chest discomfort, dizziness, angina pectoris, chest pain, and nausea. Methylxanthines, e.g., caffeine and theophylline, may interfere with the activity of Lexiscan. Aminophylline may be used to attenuate severe and/or persistent adverse reactions to Lexiscan.

Ambrisentan (alternative Names: BSF 208075; GSK 1325760; GSK1325760A; Letairis) is an endothelin receptor antagonist that is selective for the endothelin type-A (ETA) receptor. The chemical name of ambrisentan is (+)-(2S)-2-[(4,6-dimethylpyrimidin-2-yl)oxy]-3-methoxy-3,3-diphenylpropanoic acid. Ambrisentan is indicated for the treatment of pulmonary arterial hypertension. It is approved in Europe, Canada and the United States for use as a single agent to improve exercise ability and delay clinical worsening. In addition, it is approved in the United States for use in combination with tadalafil to reduce the risks of disease progression, hospitalization and to improve exercise ability. As an endothelin receptor antagonist, ambrisentan prevents endogenous endothelin peptide from constricting the muscles in blood vessels, allowing them to relax and permit a reduction in blood pressure. Endothelin-1 (ET-1) is a potent autocrine and paracrine peptide. Two receptor subtypes, ETA and ETB, mediate the effects of ET-1 in the vascular smooth muscle and endothelium. The primary actions of ETA are vasoconstriction and cell proliferation, while the predominant actions of ETB are vasodilation, antiproliferation, and ET-1 clearance. In patients with PAH, plasma ET-1 concentrations are increased as much as 10-fold and correlate with increased mean right atrial pressure and disease severity. ET-1 and ET-1 mRNA concentrations are increased as much as 9-fold in the lung tissue of patients with PAH, primarily in the endothelium of pulmonary arteries. These findings suggest that ET-1 may play a critical role in the pathogenesis and progression of PAH. Ambrisentan is a high-affinity (Ki=0.011 nM) ETA receptor antagonist with a high selectivity for the ETA versus ETB receptor (>4000-fold). The clinical impact of high selectivity for ETA is not known.

Aliskiren – the only direct renin inhibitor which is clinically used as an antihypertensive drug. Aliskiren is the first of a new class of antihypertensive agents. Aliskiren is a new renin inhibitor of a novel structural class that has recently been shown to be efficacious in hypertensive patients after once-daily oral dosing. In short-term studies, it was effective in lowering blood pressure either alone or in combination with valsartan and hydrochlorothiazide, and had a low incidence of serious adverse effects. It was approved by the Food and Drug Administration in 2007 for the use as a monotherapy or in combination with other antihypertensives. Aliskiren is marketed under the trade name Tekturna. Aliskiren effectively reduces functional plasma renin activity by binding to renin with high affinity, preventing it from converting angiotensinogen to angiotensin I. The inhibition of renin by aliskiren is associated with a reduction in circulating levels of angiotensin I and II, with a resultant increase in plasma renin concentration and inhibit activation of mitogen-activated protein kinases ERK1 (p44) and ERK2 (p42).