Efficacy and safety of a once-daily graded-release diltiazem formulation dosed at bedtime compared to placebo and to morning dosing in chronic stable angina pectoris

Bedtime GRD significantly increases exercise tolerance in patients with angina pectoris over the 24-hour dosing interval. A greater 4-fold placebo-adjusted improvement occurred between 7 and 11 am compared with the same morning dose, coinciding with the period of increased cardiovascular risk. GRD was safe and well tolerated.