Comparison of once and twice daily oral dosing schedules of bevantolol, a new beta-adrenoceptor antagonist with alpha-adrenoceptor partial antagonist activity in patients with angina of effort.

In a placebo controlled double-blind cross-over study following a dose titration phase, we compared the efficacy of benantolol, a new beta 1 adrenoceptor antagonist with alpha-adrenoceptor partial antagonist activity at 12 and 24 hours after dosing in patients with angina of effort. Twenty patients aged 43-65 years were studied. Each study phase lasted four weeks. Efficacy was determined by treadmill exercise testing using the standard Bruce protocol at the end of each phase. Fifteen patients satisfactorily completed the study. Data from five protocol violators were not analysed. In the four patients who received bevantolol 200 mg daily, exercise time increased from 395 +/- 192 (mean +/- 1 SD) sec on placebo to 468 +/- 171 sec at 10-12 hours and to 442 +/- 230 sec at 22-24 hours after dosing with bevantolol. In the eleven patients who received bevantolol 400 mg daily, exercise tolerance of 290 +/- 103 sec on placebo increased to 408 +/- 112 sec at 10-12 hours (P = 0.001) and to 400 +/- 98 sec at 22-24 hours (P = 0.001) after dosing with bevantolol. Maximum exercise capacity at 10-12 and 22-24 hours after dosing with bevantolol were comparable. Maximum exercise heart rate and systolic blood pressure on placebo and on bevantolol at 10-12 and at 22-24 hours after dosing were comparable. Thus, bevantolol has salutary effects on exertional angina up to 24 hours after dosing.