COMPARISON OF THE ANGIOTENSIN-II ANTAGONIST LOSARTAN WITH THE ANGIOTENSIN-CONVERTING ENZYME-INHIBITOR ENALAPRIL IN PATIENTS WITH ESSENTIAL-HYPERTENSION

Objective: To evaluate the blood pressure lowering efficacy as well as tolerability and safety of the angiotensin II antagonist losartan com pared with that of the angiotensin converting enzyme inhibitor enalapr il in patients with mild-to-moderate essential hypertension. Design an d methods: The study was a multicentre, double-blind, double-dummy, ra ndomized, parallel study. Patients (n = 407) with diastolic blood pres sure greater than or equal to 95 and less than or equal to 120 mmHg at the end of a 2-week baseline placebo period were randomly allocated t o receive either 50 mg losartan once a day or 20 mg enalapril once a d ay for 12 weeks. Blood pressure, clinical and laboratory safety, speci fic symptoms including coughing determined using a symptoms questionna ire and metabolic variables were examined at baseline acid at weeks 6 and 12. Results: Both loartan and enalapril decreased systolic and dia stolic blood pressure from baseline at weeks 6 and 12. Blood pressure changes from baseline at trough (22-26 h after the dose) did not diffe r between the two groups in the per-protocol analysis. Response to tre atment at trough was excellent or good (diastolic blood pressure <90 m mHg or reduction in diastolic blood pressure of 10 mmHg) in 51 and 53% of the patients in the losartan and enalapril groups, respectively. E nalapril administration increased dry coughing symptoms whereas losart an did not. The incidence of dry coughing was 1.0 and 12.2% as a spont aneously reported discomfort at week 12 and 3.0 and 15.1% as a clinica l adverse experience in the losartan and enalapril groups, respectivel y. The difference from baseline at week 12 in the incidence of dry cou ghing between the two groups was 14.9% as a specific symptom in the sy mptoms questionnaire. Losartan reduced serum uric acid concentration, whereas effects on other metabolic parameters did not differ between t he groups. Conclusions: Losartan is an effective and well-tolerated an tihypertensive drug showing similar blood-pressure-lowering efficacy t o that of enalapril at trough. However, in contrast to enalapril, losa rtan does not increase the incidence of dry coughing. Thus, the angiot ensin II antagonist losartan provides a promising new approach to trea tment of hypertension.