Antihypertensive efficacy and safety of losartan/hydrochlorothiazide (HCTZ) combinations have not been adequately studied in Asians. In this open-label, 12-week study in seven Asian areas, patients on monotherapy with angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEIs) but not at blood pressure (BP) goal (sitting diastolic BP (SiDBP) <90 mm Hg in non-diabetics and <80 mm Hg in diabetics) were switched to losartan 50 mg/HCTZ 12.5 mg. At 4 and 8 weeks, the therapy for patients not at goal BP was titrated to losartan 100 mg/HCTZ 12.5 mg and to losartan 100 mg/HCTZ 25 mg, respectively. Data analysis included 430 patients with mean (s.d.) age 53.0 (10.1) years and 51.9% of the female gender. After 8 weeks (primary end point; titration up to losartan 100 mg/HCTZ 12.5 mg), 73.5% (95% confidence interval (CI): 69.0-77.6) of patients reached BP goal; 63.4 and 78.1% of patients reached BP goal at 4 weeks (titration up to losartan 50 mg/HCTZ 12.5 mg) and at 12 weeks (titration up to losartan 100 mg/HCTZ 25 mg). The mean changes from baseline (95% CI) in sitting systolic BP and SiDBP at 8 weeks were -16.7 (-18.0 to -15.4) mm Hg and -12.1 (-12.9 to -11.4) mm Hg, respectively. Clinical and laboratory adverse experiences (AEs) were reported in 27.5 and 21.0% of patients, respectively. Nine patients were discontinued because of drug-related clinical AEs. Switching Asian patients currently not at BP goal with ARB or ACEI monotherapy to a losartan/HCTZ combination achieved BP goal in the majority of patients. Losartan/HCTZ combinations were generally well tolerated.
Trial registration: ClinicalTrials.gov NCT00354991.