Efficacy and Safety of Bepridil in Chronic Stable Angina Pectoris Refractory to Nifedipine.

: The efficacy and safety of bepridil in chronic stable angina pectoris refractory to an extended-release preparation of nifedipine were evaluated in this open-label prospective study. Patients whose angina had not responded adequately to maximum tolerated doses of nifedipine received bepridil for 8 weeks after a 2-week baseline period at their established dose of nifedipine. Twenty-five patients entered the bepridil treatment period. Total exercise time (mean plus minus SD) was significantly increased at the end of bepridil therapy (9.3 plus minus 2.3 min) compared with the end of nifedipine baseline period (8.40 plus minus 2.3 min, p = 0.02). Time to the onset of angina increased from 6.1 plus minus 2.7 min to 8.1 plus minus 2.3 min, p < 0.01. Time to 1-mm ST depression increased from 7.0 plus minus 2.7 min to 8.4 plus minus 2.3 min, p < 0.01. Nitroglycerin consumption decreased from 3.01 plus minus 5.6 to 0.56 plus minus 1.3 tablets week(minus sign1), p < 0.05. The mean weekly angina attack rate decreased from 4.34 plus minus 5.3 to 1.33 plus minus 2.2, p < 0.01. Therapy with bepridil resulted in few adverse experiences. The mean QT(c) interval was significantly prolonged from 0.40 + 0.03 s at baseline to 0.45 + 0.045 s at the end of bepridil therapy (p < 0.001). There were no serious adverse events. The results of this study indicated that bepridil provides effective and safe treatment of stable angina pectoris in patients whose angina is not adequately controlled by nifedipine.