Actively Recruiting

Phase 2
Age: 18Years +
All Genders
ID06111885

Randomized, Double-blind, Crossover Trial Comparing Indapamide, Chlorthalidone, and Hydrochlorothiazide to Reduce Urine Supersaturation for Kidney Stone Prevention

Led by Insel Gruppe AG, University Hospital Bern · Updated on 2026-05-06

99

Participants Needed

1

Research Sites

N/A

Total Duration

On this page

AI-Summary

What this Trial Is About

Researchers are investigating how two long-acting thiazide-like diuretics, indapamide and chlorthalidone, compare to the short-acting diuretic hydrochlorothiazide in reducing urine supersaturation of calcium oxalate and calcium phosphate. These substances are indicators related to the risk of calcium-containing kidney stone recurrence, a common and recurrent kidney condition causing significant discomfort and healthcare costs. The study aims to address the unclear role of thiazides in preventing kidney stone recurrence by performing a randomized, double-blind, crossover trial. Participants will receive three different active treatments: indapamide 2.5 mg once daily, chlorthalidone 25 mg once daily, and hydrochlorothiazide 50 mg once daily. Each treatment period lasts 28 days and is separated by a 28-day wash-out phase before switching to the next medication in a random order. All participants will also follow a recommended non-drug prevention plan according to current guidelines during the study. Throughout the study, participants will be closely monitored with urine and blood tests at baseline and after each 28-day treatment phase to measure changes in urine supersaturation and other biochemical markers. Blood pressure and adverse effects will also be tracked. The primary goal is to evaluate the reduction of calcium oxalate and calcium phosphate supersaturation in urine after each treatment. The total participation involves multiple treatment and wash-out phases over several months, with careful safety and efficacy assessments.

CONDITIONS

Brief Title

Indapamide and Chlorthalidone to Reduce Urine Supersaturation for Kidney Stone Prevention

Who Can Participate

Age: 18Years +
All Genders

Eligibility Criteria

Eligible

You may qualify if you...

  • Written, informed consent
  • Age 18 years or older
  • Recurrent kidney stone disease with 2 or more episodes in the last 10 years
  • Past kidney stones containing at least 50% calcium oxalate, calcium phosphate, or a mixture of both
Not Eligible

You will not qualify if you...

  • Secondary causes of recurrent calcium kidney stones such as severe eating disorders, chronic bowel disease, intestinal or bariatric surgery, sarcoidosis, primary hyperparathyroidism, or chronic urinary tract infection
  • Use of certain medications like thiazide or loop diuretics, carbonic anhydrase inhibitors, xanthine oxidase inhibitors, alkali, active vitamin D, calcium supplements, bisphosphonates, denusomab, teriparatide, SGLT2 inhibitors, strong CYP3A4 modifiers, or lithium unless discontinued 28 days prior
  • Chronic kidney disease with eGFR below 30 mL/min
  • Glomerulonephritis
  • Severe biochemical imbalances including hypercalcemia, therapy-resistant hypokalemia, severe hyponatremia, or symptomatic hyperuricemia
  • Hepatic encephalopathy or severe liver failure
  • Severe cardiac insufficiency
  • Recent cerebrovascular event
  • Solid organ transplant
  • Pregnancy or lactation
  • Participation in another interventional trial within 3 months or prior INDAPACHLOR participation
  • Inability to understand or follow the protocol
  • Allergy to any study drug

AI-Screening

AI-Powered Screening

Complete this quick 3-step screening to check your eligibility

1
2
3
+1

Your Study Journey

Screening

Duration - 2 to 4 weeks

Participants are screened for eligibility to participate in the trial.

Treatment

Duration - Approximately 24 weeks including treatment and wash-out periods

Participants receive three different thiazide medications in a random sequence, each taken once daily for 4 weeks, with 4-week wash-out periods between treatments.

3 treatment phases of 4 weeks each, each followed by a 4-week wash-out period, with visits at baseline and day 28 of each treatment phase

Trial Site Locations

Total: 1 location

1

Inselspital, Department of Nephrology and Hypertension

Bern, Switzerland, 3010

Actively Recruiting

Loading map...

Research Team

D

Daniel G Fuster, M.D.

How is the study designed?

Study Type

INTERVENTIONAL

Masking

QUADRUPLE

Allocation

RANDOMIZED

Model

CROSSOVER

Primary Purpose

PREVENTION

Number of Arms

6

Similar Trials

Two Single Arm, Multicentre Unblinded Trials Investigating a...

Catheter Blockage

Actively Recruiting

2 locations

A Single-Center Clinical Study on the Efficacy and Safety of...

Urolithiasis, Calcium Oxalate

Actively Recruiting

1 location

Frequently Asked Questions

Have more questions? Get in touch with our team for quick support

Not the Right Trial for You?

Explore thousands of other clinical trials that might be a better match.
Sign up to get personalized trial recommendations delivered to your inbox.

Already have an account? Log in here

Published Research Related To This Trial

Indapamide or chlorthalidone to reduce urine supersaturation for secondary prevention of kidney stones: protocol for a randomised, double-blind, cross-over trial (INDAPACHLOR).

Martin Scoglio, Matteo Bargagli, Felix Rintelen...

https://pubmed.ncbi.nlm.nih.gov/40523783