COMPARISON OF 2 EXTENDED-RELEASE VERAPAMIL FORMULATIONS IN PATIENTS WITH MILD-TO-MODERATE HYPERTENSION

The efficacy and safety of two extended-release formulations of verapamil were compared in patients with mild to moderate hypertension using a three-phase, double-blind, randomized, crossover design. A total of 59 evaluable patients were enrolled in a 4-week, single-blind placebo lead-in period, followed by randomization to either Verelan(R) 240 mg or Calan(R) SR 240 mg for 6 weeks, after which they were crossed over to the alternate therapy for 6 weeks. Efficacy was assessed by blood pressure measurements taken in the physician's office 24 hours postdose and by 24-hour ambulatory blood pressure monitoring (ABPM). Both verapamil formulations significantly reduced office diastolic (DBP) and systolic (SBP) blood pressure. ABPM confirmed the drugs' antihypertensive efficacy. Both medications reduced ambulatory DBP and SBP during the initial 8 hours after dosage and over the entire 24-hour interval. A significantly greater decrease (P less-than-or-equal-to .03) in ambulatory SBP occurred during the last 4 hours of the 24-hour interval (trough effect) with Verelan than with Calan SR. Office SBP results, also a trough effect, showed a trend toward greater reduction in SBP during Verelan treatment. Both verapamil formulations were well tolerated: 6 (20%) patients treated with Calan SR and 3 (9%) patients treated with Verelan experienced drug-related adverse events, most frequently headache and constipation.