Fosinopril monotherapy: Relationship between blood pressure reduction and time of administration

Abstract The time to peak antihypertensive effect and the trough‐to‐peak ratio were determined in 64 Caucasian patients (19 men, 45 women) with mild to moderate hypertension [supine diastolic blood pressure (DBP) 95 to 115 mmHg]. They received placebo or fosinopril 10, 20, or 40 mg once daily for 4 weeks. The study consisted of a 4‐week placebo lead‐in, 4 weeks' double‐blind treatment, and a 1‐week placebo washout period. Vital signs were determined biweekly before dosing, and blood pressures were measured every 1 to 2 h during two 27‐h periods at the beginning and end of treatment. After the first and last doses of all three regimens, the peak effect on blood pressure occurred 5 to 7 h after all three dosages. Neither peak nor trough blood pressure changes showed a clear dose‐response relationship. Trough to peak ratios for the first dose, corrected for placebo effects, were 79% for fosinopril 10 mg, 48% for fosinopril 20 mg, and 74% for fosinopril 40 mg, and the trough‐to‐peak ratios for the last dose were 41% for fosinopril 10 mg, 32% for fosinopril 20 mg, and 44% for fosinopril 40 mg. In the 38 responders among the 48 patients receiving fosinopril (supine DBP decrease of at least 5 mmHg at 24 h postdose), trough‐to‐peak rations ranged from 50 to 81%, and the range indicates that fosinopril is efficacious when administered once daily. Adverse effects were mild to moderate, and no patient discontinued treatment. Changes in the laboratory test results, electrocardiograms, or the results of physical examinations were unremarkable. Once‐daily fosinopril 10, 20, or 40 mg effectively and safely controlled blood pressure in patients with mild to moderate essential hypertension.