BLOOD-PRESSURE CONTROL WITH DILTIAZEM XR, A NOVEL EXTENDED-RELEASE FORMULATION OF DILTIAZEM HCL, IN MATURE AND ELDERLY HYPERTENSIVE PATIENTS

The safety and efficacy of an extended-release form of diltiazem HCl ( diltiazem XR) in patients 55 years or older with mild-to-moderate esse ntial hypertension were examined in a multicenter, double-blind, rando mized, placebo-controlled, parallel-group study involving 350 patients with supine diastolic blood pressure (DBP) between 95 mm Hg and 114 m m Hg. Patients were randomized to a once-daily dose of diltiazem XR (2 40 mg) or placebo; 261 patients received diltiazem XR and 89 received placebo. After 4 weeks, the dose was doubled (to 480 mg) in patients w hose supine DBP was >90 mm Hg, and treatment was continued for another 4 weeks. Diltiazem XR consistently reduced blood pressure (BP) in the study population. At end-point, the mean reduction in supine DBP was 8.65 mm Hg in the diltiazem XR group and 2.75 mm Hg in the placebo gro up (P < 0.0001). Subgroup analysis confirmed the efficacy of diltiazem XR in men, women, patients between the ages of 55 and 64 years, patie nts 65 years or older, and non-black patients. Other BP values (supine systolic, standing diastolic, and standing systolic) also were signif icantly reduced in patients treated with diltiazem XR. BP reduction (s upine DBP less-than-or-equal-to 90 mm Hg or by grater-than-or-equal-to 10 mm Hg) was achieved in 58% of patients receiving diltiazem XR comp ared with 27% of patients receiving placebo. Decreases in apical heart rate were minimal and similar in both groups. No significant differen ces were noted in adverse events in the diltiazem XR and placebo group s: 36.4% of patients in the diltiazem XR group and 37.1% in the placeb o group had no adverse experiences, and 63.6% and 62.9%, respectively, had at least one adverse event. Physical examination findings and lab oratory values were clinically unremarkable and comparable in the dilt iazem XR and placebo groups. Diltiazem XR given once daily at doses of 240 mg and 480 mg was safe and effective in lowering blood pressure i n mature and elderly patients with mild-to-moderate hypertension.