Effects of eprosartan versus enalapril in hypertensive patients on the renin-angiotensin-aldosterone system and safety parameters: Results from a 26-week, double-blind, multicentre study

A double-blind comparator study was performed in 528 hypertensive patients [baseline sitting diastolic blood pressure (SitDBP) 95-114 mmHg]. The primary objective was to compare the incidence of drug-related cough in patients treated with enalapril and eprosartan. The secondary objective was to compare antihypertensive efficacy between treatments. This paper reports the effects seen on the safety profile, plasma renin activity, aldosterone and angiotensin II (A-II) in each treatment group. Eprosartan was titrated from 200 mg b.i.d. to 300 mg b.i.d. and enalapril from 5 mg o.d. to 20 mg o.d. over 12 weeks. Hydrochlorothiazide (HCTZ) 12.5-25 mg o.d. could be added where required to the treatment for the final six weeks of the titration phase if SitDBP greater than or equal to 90 mmHg. Patients received the maximum titrated dosage during the maintenance phase. In the study overall, similar mean changes in blood pressure from baseline were evident with each treatment. Measurement of mean plasma neurohormone levels showed significant increases in renin activity in both groups and statistically significant A-II elevations in the eprosartan group (p < 0.05). Neither eprosartan nor enalapril significantly altered serum lipid profiles or electrolyte levels. Most adverse experiences reported throughout the study were mild or moderate in both treatment groups. Fewer patients receiving eprosartan (4.9%) than enalapril (9.1 %) discontinued treatment because of adverse experiences. In conclusion, the results of this study show that eprosartan is well tolerated. Both eprosartan and enalapril significantly increased plasma renin activity while plasma A-II was elevated in the eprosartan group.