Losartan and Uric Acid Metabolism in Children With Proteinuric Nephropathies

Hospital General de Niños Pedro de Elizalde

Status and phase: Enrolling; Phase 4

Conditions: Uric Acid Nephropathy

Treatments: Drug: Losartan Potassium

Study type: Interventional

Funder types: Other

Identifiers

NCT05402397

HGNPE 7122

Details and patient eligibility

About

The aim of this study is to assess the serum uric-acid lowering effect of losartan in children with proteinuric nephropathies. Patients already treated with enalapril will be randomized to receive losartan and/or enalapril in a cross-over designed study. Those who recruit the inclusion criteria will receive enalapril and/or losartan during a one month period, followed by a 15 days of wash out (under enalapril treatment). On day 46, the second period of 30 days of treatment start (enalapril or losartan, whichever was not received initially). Before randomization, a baseline 24 hours urine and a fasting blood sample will be obtained to assess uric acid excretion and serum uric acid values along with renal function and electrolyte levels. Then, similar determinations will be performed at days 30, 46 and 76.

Full description

The working hypothesis is that the administration to losartan reduces significantly the serum uric acid levels in normotensive children with proteinuric nephropathies. The study will consist in a single center cross-over randomized, open label, clinical trial.

Inclusion criteria will be:children with poteinuric nephropathies already treated with enalapril under our care, age between 3 and 12 years and normal blood pressure.

Subjects will be selected by simple probability sampling and after the signature of the assent/informed consent, they will be randomized (blocks of 4 patients, treatment sequence 2:2) to receive a two phases regime of drugs: 1) arm enalapril-losartan, or 2) arm losartan-enalapril. Between phases there will be a 14 days wash out period (during this time patients will continue receiving enalapril, as this drug does not have effect on uric acid metabolism). The dose of enalapril will be that they usually receive, while the dose of losartan will be 5 times the those of enalapril that they usually receive.

Visit Schedule: day 1 (randomization) and 30 for the first drug; 15 days wash out period, day 46 and 76 for the second drug. In each visit a physical examination and blood pressure monitor will be performed, along with the following laboratory parameters: urea, creatinine, electrolytes, uric acid, glycemia, triglycerides, cholesterol and lipopolysaccharides. Simultaneously, in a spot urine morning sample will be determined the levels of uric acid, creatinine, proteinuria y albuminuria.

Enrollment: 40 estimated patients

Sex: All

Ages: 3 to 12 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Children with poteinuric nephropathies already treated with enalapril under our care.
• Age between 3 and 12 years.
• Normal blood pressure.

Exclusion criteria

• Patients with high blood pressure.
• Post menarche female patients.
• Patients with hypouricemia (< 2 mg/dL).
• Patients treated with diuretics.
• Patients with absolute or relative contraindications to receive RAAS antagonists (glomerular filtration < 30 ml/min/1,73 m2, serum potassium > 5,5 mEq/L).
• Patients with active rheumatic diseases.
• Patients treated with dual blockade of the RAAS (enalapril +losartan).
• Patients treated with calcineurin inhibitors.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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40 participants in 2 patient groups

Enalapril

Active Comparator group

Description:

Children with proteinuric nephropathies will receive enalapril prior or after a losartan period, according to randomization sequence. Enalapril will be given at a dose between 0.1 to 0.4 mg/kg/day (according to the dose that they usually receive), once a day.

Treatment:

Drug: Losartan Potassium

Losartan

Experimental group

Description:

Children with proteinuric nephropathies will receive losartan prior or after a enalapril period, according to randomization sequence. Losartan will be given at a dose 5 times the dose of enalapril that they usually receive, (with a maximum dose of 1.4 mg/kg/day), once a day.

Treatment:

Drug: Losartan Potassium