Effects of omapatrilat on hemodynamics and safety in patients with heart failure.

Omapatrilat, a novel vasopeptidase inhibitor, is a highly potent and selective inhibitor of neutral endopeptidase and angiotensin-converting enzyme; its therapeutic potential is being investigated for treatment of hypertension and heart failure. In the present study, the safety, tolerability, and hemodynamic effects of single oral doses of omapatrilat (1 to 50 mg) are compared with placebo in patients with heart failure. Patients with heart failure (New York Heart Association functional class II to IV) and a resting left ventricular ejection fraction < or = 40% were enrolled in a double-blind, placebo-controlled, sequential-panel study of single doses of omapatrilat of 1, 2.5, 5, 10, 25, or 50 mg, followed by hemodynamic assessment for 24 hours. At 4 to 6 hours after dosing, the 25- and 50-mg doses of omapatrilat, compared with placebo, reduced mean pulmonary capillary wedge pressure by approximately 6 mm Hg from 20 and 23 mm Hg at baseline to 14 and 16 mm Hg. The 50-mg omapatrilat dose maintained this effect compared with placebo with an approximately 2.5-mm Hg reduction in mean pulmonary capillary wedge pressure at 24 hours. Omapatrilat improved additional hemodynamic parameters, including cardiac index, systemic vascular resistance, stroke volume index, and mean arterial pressure. Additionally, by 2 hours after dosing with omapatrilat 25 and 50 mg, a trend in peak increases from baseline in plasma atrial natriuretic peptide (twofold) and cyclic guanosine monophosphate (nearly twofold) was observed. Moreover, omapatrilat was well tolerated. Thus, omapatrilat administered orally to patients with heart failure was safe and well tolerated and resulted in improved hemodynamic performance.