This study was a randomized, double-blind, double-dummy, parallel-group, active-controlled, two-arm trial to compare LCZ696 200 mg twice daily (bid) to enalapril 10 mg bid in improving exercise capacity, daily physical activity and quality of life in patients with stable chronic heart failure (New York Heart Association III) and reduced left ventricular ejection fraction (LVEF ≤ 40%).~The study consisted of a screening period of 2 weeks during which the subject's eligibility for the study was assessed followed by a double blind treatment period of 12 weeks. Eligible subjects were randomized 1:1 to receive either LCZ696 or enalapril during the double-blind period. Treatment was initiated with LCZ696 100 mg bid or enalapril 5 mg bid (enalapril 10 mg bid for patients at a stable daily dose of enalapril above 10 mg per day or corresponding doses of other angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB) prior first screening visit), respectively. Dose was up-titrated after 2 weeks to the final dose of LCZ696 200 mg bid or enalapril 10 mg bid.~Patients continued to take their background medications for chronic heart failure during the study, with the exception of ACEI or ARBs which were replaced by investigational treatment and had to be discontinued before first dose of study drug.~The primary objective was to demonstrate the superiority of LCZ696 200 mg bid compared to enalapril 10 mg bid in improving exercise tolerance (peak respiratory oxygen uptake (VO2peak), adjusted to body weight) as assessed by cardio-pulmonary-exercise testing (CPET) in patients with stable chronic heart failure (NYHA III) and reduced ejection fraction (LVEF ≤ 40%) after 3 months treatment.
The purpose of the study was to determine the effect of LCZ696 vs. enalapril on improvement of exercise capacity in patients with chronic heart failure with reduced ejection fraction.