Patients and method: This double-blind study compared the efficacy and safety of once daily amlodipine (5-10 mg/day) vs twice daily nifedipine (40-80 mg/day) in 244 patients with chronic stable angina pectoris. Efficacy was assessed after 4 and 24 weeks by bicycle exercise test.
Results: No statistically significant differences were found between the two treatment groups at the end of treatment with regard to the ergometry parameters determined (maximum ST segment deviation, maximum workload in watts, maximum exercise duration and time to 0.1 mV ST segment depression). Furthermore, the two treatment groups were comparable with regard to the effected reduction in anginal attacks and short acting nitrate consumption. The incidence of adverse events was lower in the amlodipine relative to the nifedipine group (11.5% vs 19.1%).
Conclusion: The results of this study show that once daily amlodipine offers comparable antianginal and antiischemic efficacy as twice daily sustained release nifedipine in the monotreatment of chronic stable angina pectoris. Given the lower incidence of adverse events with amlodipine and its convenient once daily dosing regimen, however, amlodipine may help to enhance patient compliance.