A new extended-release formulation of diltiazem HCl for the treatment of mild-to-moderate hypertension.

Calcium-channel blockers are a safe and effective treatment modality and have been used extensively in the treatment of angina and hypertension. Dilacor XR capsules, a new extended-release formulation of diltiazem, has been developed for the treatment of hypertension. Dilacor XR (Rhône-Poulenc Rorer Pharmaceuticals Inc., Collegeville, PA) uses a novel drug delivery system, the Geomatrix (JAGO Research AG, Zollikon, Switzerland) controlled-release system, to deliver diltiazem at a constant rate for 24 hours. The rate of absorption is also slower. As doses of Dilacor XR were increased from 120 mg to 540 mg/day, there were disproportionate increases observed in area under the curve, maximum peak plasma concentration, minimum peak plasma concentration, and average peak plasma concentration. The efficacy data from two clinical trials have confirmed the established efficacy of diltiazem and the 24-hour efficacy of Dilacor XR in the control of mild-to-moderate hypertension. The incidence of adverse effects with Dilacor XR in doses as high as 540 mg/day was generally comparable to that of placebo. This new extended-release formulation of diltiazem should significantly facilitate blood pressure control because of better patient compliance with a once daily regimen.