This double-blind study was conducted to investigate the efficacy, saf
ety and tolerability of three dose levels of moexipril in comparison t
o placebo as add-on therapy to hydrochlorothiazide (HCTZ) in patients
with moderate to severe hypertension. Two hundred patients who did not
respond adequately to a 4-week monotherapy with HCTZ - sitting diasto
lic blood pressure between 95 and 114 mm Hg - entered the 8-week doubl
e-blind period. Patients were randomized to once daily placebo or moex
ipril 3.75, 7.5 or 15 mg as add-on therapy to open-label HCTZ 25 mg. A
t biweekly visits, blood pressure and heart rate measurements were obt
ained and the occurrence of adverse experiences was documented. At the
8-week endpoint, adjusted mean reductions from baseline were signific
antly (p = 0.003) greater in patients receiving moexipril 3.75, 7.5 an
d 15 mg compared to placebo (-8.4, -8.8 and -8.9 vs. -4.6 mm Hg). No s
ignificant differences between the three dose levels of moexipril coul
d be observed. Moexipril was generally well tolerated. The most freque
ntly reported adverse events for moexipril and placebo were headache,
flu syndrome and dizziness (6, 7, 5 vs. 4, 0, 4%). The results indicat
e that the combination of moexipril and HCTZ is a clinically valuable
combination in the treatment of patients with moderate to severe hyper
tension.