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.
Abstract

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