Blood Pressure Response to Zofenopril or Irbesartan Each Combined with Hydrochlorothiazide in High-Risk Hypertensives Uncontrolled by Monotherapy: A Randomized, Double-Blind, Controlled, Parallel Group, Noninferiority Trial

In this randomized, double-blind, controlled, parallel group study (ZENITH), 434 essential hypertensives with additional cardiovascular risk factors, uncontrolled by a previous monotherapy, were treated for 18 weeks with zofenopril 30 or 60 mg plus hydrochlorothiazide (HCTZ) 12.5 mg or irbesartan 150 or 300 mg plus HCTZ. Rate of office blood pressure (BP) response (zofenopril: 68% versus irbesartan: 70%; p = 0.778) and 24-hour BP response (zofenopril: 85% versus irbesartan: 84%; p = 0.781) was similar between the two treatment groups. Cardiac and renal damage was equally reduced by both treatments, whereas the rate of carotid plaque regression was significantly larger with zofenopril. In conclusion, uncontrolled monotherapy treated hypertensives effectively respond to a combination of zofenopril or irbesartan plus a thiazide diuretic, in terms of either BP response or target organ damage progression.