The Circadian Anti-Ischemic Program in Europe (CAPE) trial was a large, multinational trial, taking place in ten countries and involving over 100 investigators. It was a double-blind, parallel, randomized, placebo-controlled trial comparing once-daily amlodipine with placebo in chronic stable angina pectoris. It consisted of two phases, the first being a 2-week, single-blind, placebo run-in phase during which stable doses of anti-anginal drugs were maintained (65% of patients were receiving β-blockers), and the second an 8-week active treatment phase in which patients received either amlodipine or placebo, 5 mg once daily, for the first 4 weeks, increasing to 10 mg once daily for the second 4 weeks. Patients were randomized in a ratio of 2 patients receiving amlodipine to each patient receiving placebo. Out of an initial 1,160 patients screened, 315 entered the study, with 250 having complete efficacy-evaluable data. Patients were included if they experienced ≧ 4 ambulatory ECG ischemic episodes (≧ 1 mm ST-segment depression for > 1 min) and/or ≧ 20 min total ischemia time over 48 h. Data were obtained on the total frequency of ST-segment depression events, the ischemia area (ST-segment depression integral), the ischemic time and peak ST-segment depression. Patient diary information on angina attack rate and nitroglycerin tablet consumption was also collected. Patients in both groups were compared for age, blood pressure, heart rate, duration of angina and baseline ischemia at entry. Amlodipine and placebo had similar safety profiles, with 17.3% of amlodipine patients recording adverse events, compared with 13.3% of placebo patients. Angina pectoris was noted as a complaint by 2% of patients receiving amlodipine, compared with 3.5% receiving placebo. Edema was noted in 5.4% of amlodipine patients and 1.8% of placebo patients and headache was reported by 2.5% of amlodipine patients and 0.9% of placebo patients. In general, complaints were not severe and the withdrawal rate was low (amlodipine 2%, placebo 4%). None of the above differences was statistically significant. In conclusion, the baseline demographic and ischemic profiles for patients receiving either amlodipine or placebo were similar. Amlodipine was very well tolerated, as shown by a safety profile similar to that of placebo and a low withdrawal rate from the study.