Abstract: PUB065
Indapamide and Chlorthalidone to Reduce Urine Supersaturation for Secondary Prevention of Kidney Stones: Randomized, Double-Blind, Crossover Trial (INDAPACHLOR Trial)
Session Information
Category: Bone and Mineral Metabolism
- 502 Bone and Mineral Metabolism: Clinical
Authors
- Scoglio, Martin, Inselspital Universitatsspital Bern Universitatsklinik fur Nephrologie und Hypertonie, Bern, Switzerland
- Bargagli, Matteo, Inselspital Universitatsspital Bern Universitatsklinik fur Nephrologie und Hypertonie, Bern, BE, Switzerland
- Fuster, Daniel G., Inselspital Universitatsspital Bern Universitatsklinik fur Nephrologie und Hypertonie, Bern, BE, Switzerland
Group or Team Name
- Daniel Fuster's Group.
Background
Kidney stones constitute a major global healthcare problem characterized by high recurrence rates. The majority of kidney stones consist of calcium and a high urine calcium (“hypercalciuria”) is the predominant metabolic abnormality in patients with kidney stones. The NOSTONE trial recently demonstrated that hydrochlorothiazide (HCT) has limited efficacy in preventing recurrence. Our objective is to assess whether indapamide or chlorthalidone are more effective than HCT in reducing urine supersaturations (RSRs) for calcium oxalate and calcium phosphate, which are validated predictors of stone recurrence.
Methods
INDAPACHLOR is a single-center, randomized, double-blind, cross-over trial evaluating the efficacy of indapamide or chlorthalidone compared to hydrochlorothiazide in lowering urine RSRs for calcium oxalate and calcium phosphate in individuals with idiopathic calcium kidney stones. Participants will be allocated to indapamide 2.5 mg once daily, chlorthalidone 25 mg once daily, and hydrochlorothiazide 50 mg once daily in a random sequence. The three consecutive active treatment periods of 28 days each will be separated by wash-out periods of 28 days. The primary outcomes are the changes of the RSR calcium oxalate and RSR calcium phosphate from baseline to day 28 of each treatment period. Secondary outcomes include changes in 24 h urine and blood parameters from baseline to day 28 of each treatment period. The study targets enrollment of 99 participants to achieve 80% power for detecting a 20% reduction in RSR calcium oxalate or calcium phosphate when treated with indapamide or chlorthalidone compared to HCT.
Results
The INDAPACHLOR trial is registered at ClinicalTrials.gov (NCT06111885). Approval was obtained from the Cantonal Ethics Commission Bern (No. 2024_00477, May 28, 2024) and from the Competent Authority Swissmedic (No. 701824, June 27, 2024). Patient recruitment commenced in December 2024. As of mid-May 2025, a total of 39 patients have been recruited. Of these, 34 participants completed the first treatment phase, and 17 the second phase. The study was initially expected to conclude by the end of 2027; however, current recruiting rates indicate it may finish earlier than anticipated.
Conclusion
No conclusions available — study in progress.
Funding
- Government Support – Non-U.S.