A Crossover Pilot Study of the Effect of Amiloride on Proteinuria
- Registration Number
- NCT02522650
- Lead Sponsor
- Georgetown University
- Brief Summary
This cross-over study is designed to test the hypothesis that amiloride will reduce urinary protein excretion and protect the kidney from rapid progression in proteinuric kidney disease.
- Detailed Description
Patients with proteinuric kidney disease will be enrolled and receive either amiloride or triamterene first, a similar diuretic acting on epithelial sodium channel (ENaC) as amiloride, but not inhibiting urokinase plasminogen activator receptor (uPAR), will be used as a control. Then patients will cross over to receive another medication. We postulate that amiloride could be beneficial in the patients with proteinuric kidney diseases and could be used as an adjunct therapy to reduce proteinuria and to delay renal disease progression in this patient population.
Specific Aim 1: To examine the effects of amiloride on 24 hour urine protein excretion in patients with proteinuric kidney diseases.
Specific Aim 2: To study if the effect of amiloride on proteinuria reduction is mediated by suppressing soluble urokinase plasminogen activator receptor (suPAR) expression.
Study Design:
The study includes 3 phases. 30 patients will be recruited to this study. All patients need to be on an angiotensin converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB) daily at least two month prior to the study.
Phase 1: Patients will be randomized to receive either amiloride 5mg twice daily or triamterene 50mg twice daily for 8 weeks. Serum potassium will be monitored one week before and one week after starting phase 1. If serum potassium remains equal to or less than 5.0mmol/L, amiloride or triamterene will be continued at same dose until the end of phase 1. If serum potassium is equal to or above 5.5 mmol/L, the patient will exit the study, and an adverse event will be reported. If serum potassium is between 5.1-5.4 mmol/L, it will be monitored again in one week. If serum potassium is above 5.5 mmol/L, the patient will exit the study, and an adverse event will be reported. If serum potassium remains in the same range, the patient will continue amiloride or triamterene at the same dose to complete phase 1.
Phase 2: the patients will discontinue amiloride or triamterene for a washout for 4 weeks, but continue with the ACE inhibitor or ARB.
Phase 3: the patients will cross over to triamterene or amiloride for 8 weeks. Use the protocol as described in phase 1.
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 30
- Patient with any type of proteinuric kidney diseases
- Aged 18-75
- Proteinuria ≥1g/day
- estimated glomerular filtration rate (eGFR) ≥ 30ml/min/1.73m2
- Clinical evidences of lupus nephritis, or HIV associated nephropathy
- eGFR <30ml/min/1.73m2
- Requirement for treatment with mineralocorticoid receptor antagonists (spironolactone, eplerenone)
- Status post kidney transplant
- Received glucocorticoid steroids within six months
- Serum K >4.8 mmol/L
- Total carbon dioxide <17 mmol/L
- Hemoglobin <10 g/dl
- Contraindicated or allergic to loop diuretics or potassium sparing diuretics
- Abnormal liver function tests
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Amiloride Phase Amiloride Subject receives 5mg of Amiloride twice daily for 8 weeks. Triamterene Phase Triamterene Subject receives 50mg of Triamterene twice daily for 8 weeks.
- Primary Outcome Measures
Name Time Method 24 hr urine protein excretion 20 weeks Identify changes in 24 hr urine protein excretion throughout the 3 phases of the study.
- Secondary Outcome Measures
Name Time Method serum suPAR concentration 20 weeks examine serum suPAR concentration during the 3 phases of the study. suPAR concentration will be measured by ELISA kit.
urine plasmin activity 20 weeks examine urine plasmin activity during the 3 phases of the study. Serum and urine plasmin will be measured by gelatin-PAGE zymography.
urine plasminogen activity 20 weeks examine urine plasminogen activity during the 3 phases of the study. urine plasminogen will be measured by gelatin-PAGE zymography.
urine suPAR concentration 20 weeks examine urine suPAR concentration during the 3 phases of the study. suPAR concentration will be measured by ELISA kit.
Trial Locations
- Locations (1)
Georgetown University
🇺🇸Washington, District of Columbia, United States