Long-term systemic arterial blood pressure control with nicardipine

Nicardipine was administered orally for up to 1 year to 250 patients with essential hypertension. Phase I, a 2- to 4-week placebo washout to establish baseline supine diastolic blood pressure (BP), was followed by 4 weeks of open-label nicardipine dose titration (phase II) to establish optimal dosage on a 3-times-daily regimen for each patient. After nicardipine administration, approximately 79% of the patients had supine diastolic BP less than 90 mm Hg or greater than or equal to 10 mm Hg below baseline. The reduction in systolic and diastolic BPs was somewhat greater in patients older than 60 years. After phase III--an 8-week double-blind comparison of dosage regimens of 2- and 3-times-daily--all patients returned to a 3-times-daily regimen at their optimal daily dosage for 40 weeks of open treatment (phase IV). Supplemental treatment with a diuretic or a beta blocker was required by 67 patients. By the end of phase IV, more than 100 patients had completed 1 year of nicardipine monotherapy (mean supine diastolic BP = 85 mm Hg, approximately 14 mm Hg below baseline). Finally, patients were randomly assigned to continue nicardipine on a double-blind basis or take a matching placebo for 6 weeks (phase V, n = 101). The nicardipine group had only a slight change in supine diastolic BP, whereas those receiving placebo had statistically significant increases in supine diastolic BP toward baseline values. Adverse experiences, attributed to the vasodilatory effects of nicardipine, tended to occur in the first few months of the study and resulted in early withdrawal of 30 patients. Overall, these results show that nicardipine is a well-tolerated antihypertensive agent with efficacy sustained during 1 year of treatment.