After 2 weeks of placebo run-in period , 315 patients at 6 centers with diastolic blood pressure ( DBP ) between 95 to 109 mm Hg ( 1 mm Hg = 0.133 kPa ) while systolic blood pressure ( SBP ) below 180 mm Hg were randomized to receive aranidipine 5-20 mg/d ( n = 126 ) or retard-released felodipine 5-10 mg/d ( n = 126 ) for 12 weeks .