Efficacy of fixed-dose amlodipine and losartan combination compared with amlodipine monotherapy in stage 2 hypertension: a randomized, double blind, multicenter study

Abstract

Background: The objective of this trial was to compare the blood-pressure lowering efficacy of amlodipine/losartan combination with amlodipine monotherapy after 6 weeks of treatment in Korean patients with stage 2 hypertension.

Results: In this multi-center, double-blind, randomized study, adult patients (n = 148) with stage 2 hypertension were randomized to amlodipine 5 mg/losartan 50 mg or amlodipine 5 mg. After 2 weeks, patients with systolic blood pressure (SBP) > 140 mmHg were titrated to amlodipine 10 mg/losartan 50 mg or amlodipine 10 mg. After 4 weeks of titration, hydrochlorothiazide 12.5 mg could be optionally added to both groups. The change from baseline in SBP was assessed after 6 weeks. The responder rate (defined as achieving SBP < 140 mmHg or DBP < 90 mmHg) was also assessed at 2, 6 and 8 weeks as secondary endpoints. Safety and tolerability were assessed through adverse event monitoring and laboratory testing. Baseline demographics and clinical characteristics were generally similar between treatment groups. Least-square mean reduction in SBP at 6 weeks (primary endpoint) was significantly greater in the combination group (36.5 mmHg vs. 31.6 mmHg; p = 0.0117). The responder rate in SBP (secondary endpoints) was significantly higher in the combination group at 2 weeks (52.1% vs. 33.3%; p = 0.0213) but not at 6 weeks (p = 0.0550) or 8 weeks (p = 0.0592). There was no significant difference between groups in the incidence of adverse events.

Conclusion: These results demonstrate that combination amlodipine/losartan therapy provides an effective and generally well-tolerated first line therapy for reducing blood pressure in stage 2 hypertensive patients.

Trial registration: ClinicalTrials.gov: NCT01127217.

Figures

Figure 1

Patients Disposition (ITT: intention to treatment, PP: Per protocol).

Figure 2

Change from baseline in SBP (mmHg) in the ITT population (N = 148).

Figure 3

Changes from baseline in DBP (mmHg) in the ITT population (N = 148).

Figure 4

Responder rate for SBP < 140 mmHg at Week 2, Week 6 and Week 8 (ITT population; N = 148).

Figure 5

Cumulative responder rate for subjects achieving SBP < 140 mmHg, DBP < 90 mmHg, change in SBP > 20 mmHg or change in DBP > 10 mmHg at Week 2, Week 6 and Week 8 (ITT population; N = 148).