A RANDOMIZED, DOUBLE-BLIND TRIAL COMPARING MIBEFRADIL AND AMLODIPINE - 2 LONG-ACTING CALCIUM-ANTAGONISTS WITH SIMILAR EFFICACY BUT DIFFERENT TOLERABILITY PROFILES

Objective: To compare the efficacy and tolerability of mibefradil and amlodipine in patients with uncomplicated mild-to-moderate essential h ypertension, Design: A double-blind, randomised, parallel group multic entre trial. Methods: 239 patients received 50 mg mibefradil or 5 mg a mlodipine for 4 weeks, followed by a forced titration to 100 mg mibefr adil or 10 mg amlodipine for an additional 8 weeks. Patients then ente red a 4-week withdrawal period either on therapy or switched to placeb o. Results: Statistically equivalent reductions in trough sitting dias tolic blood pressure (SDBP) were observed after 12 weeks of once-daily treatment with 50/100 mg mibefradil (-11.5 +/- 8.2 mm Hg) and 5/10 mg amlodipine (-13.2 +/- 7.9 mm Hg). The number of patients with normali sed SDBP (less than or equal to 90 mm Hg) increased 23.3% in the mibef radil group and 19.5% in the amlodipine group (approximately 74% in bo th groups). Patients on mibefradil or amlodipine during the withdrawal period had significantly larger decreases in SDBP than those on place bo. Patients on mibefradil had a decrease in heart rate of 5.5 bpm. Pa tients on amlodipine had no change in heart rate; however, cessation o f amlodipine was associated with a decrease in heart rate. Conclusions : Mibefradil was as effective as amlodipine in reducing BP; both compo unds were effective treatments of hypertension.