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A randomized, open-label, dose-response study of losartan in hypertensive children
Nicholas J A Webb1, Thomas G Wells2, Shahnaz Shahinfar3
1Department of Paediatric Nephrology and National Institute for Health Research/Wellcome Trust Children's Clinical Research Facility, University of Manchester, Manchester Academic Health Science Centre, Royal Manchester Children's Hospital, Manchester, United Kingdom; nicholas.webb@cmft.nhs.uk.
Insights
Losartan effectively lowered blood pressure (BP) in young children, but no clear dose-response was found. The medication was well-tolerated in this hypertensive pediatric population.
Area of Science:
- Pediatric Nephrology
- Cardiovascular Pharmacology
- Clinical Hypertension
Background:
- Hypertension in children aged 6 months to 6 years requires effective treatment.
- Losartan is known to reduce blood pressure (BP) in older children.
- The dose-response relationship and safety of losartan in younger children were previously unevaluated.
Purpose of the Study:
- To assess the dose-response relationship of losartan in hypertensive children aged 6 months to 6 years.
- To evaluate the safety and tolerability of losartan in this pediatric population.
- To determine the efficacy of losartan in reducing systolic and diastolic blood pressure.
Main Methods:
- A 12-week, randomized, open-label, dose-ranging study.
- Patients received losartan at 0.1, 0.3, or 0.7 mg/kg/day, with titration up to 1.4 mg/kg/day.
- Dose response was analyzed by changes in sitting systolic (SBP) and diastolic BP (DBP) after 3 weeks; adverse events (AEs) were recorded.
Main Results:
- Mean SBP and DBP decreased from baseline across all losartan dose groups.
- No statistically significant dose-response relationship was established for SBP or DBP.
- Adverse events were infrequent and comparable across all treatment groups.
Conclusions:
- Losartan demonstrated clinically significant BP reduction in hypertensive children aged 6 months to 6 years.
- No clear dose-response relationship was evident within the studied dosage range.
- Losartan was well-tolerated up to 1.4 mg/kg/day in this young pediatric population.
Background And Objectives:
Once-daily losartan reduces BP in a dose-dependent manner and is well tolerated in hypertensive children aged 6-16 years. This study assessed the dose-response relationship, safety, and tolerability of losartan in hypertensive children aged 6 months to 6 years.
Design, Setting, Participants, & Measurements:
This was a 12-week, randomized, open-label, dose-ranging study, with a 2-year extension. Patients were randomized to losartan at the following dosages: 0.1 mg/kg per day (low), 0.3 mg/kg per day (medium), or 0.7 mg/kg per day (high). Losartan was titrated to the next dose level (to a 1.4 mg/kg per day maximum dosage, not exceeding 100 mg/d, which was not one of the three original doses offered at randomization) at weeks 3, 6, and 9 for patients who did not attain their goal BP and were not taking the highest dose. Dose response was evaluated by analyzing the slope of change in sitting systolic BP (SBP; primary end point) and diastolic BP (DBP; secondary end point) after 3 weeks compared with baseline. Adverse events (AEs) were recorded throughout.
Results:
Of the 101 patients randomized, 99 were included in the analysis (low dose, n=32; medium dose, n=34; and high dose, n=33). Mean sitting BP decreased from baseline in the low-, medium-, and high-dose groups by 7.3, 7.6, and 6.7 mmHg, respectively, for SBP and 8.2, 5.1, and 6.7 mmHg, respectively, for DBP after 3 weeks. No dose-response relationship was established by the slope analysis on SBP (P=0.75) or DBP (P=0.64). The BP-lowering effect was observed throughout the 2-year extension. The incidence of AEs was low and comparable between groups.
Conclusions:
Hypertensive children aged 6 months to 6 years treated with losartan 0.1-0.7 mg/kg per day had clinically significant decreases from baseline in SBP and DBP, yet no dose-response relationship was evident. Losartan, at a dosage up to 1.4 mg/kg per day, was well tolerated.
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