Reducing oxalate absorption to lower kidney stone risk

A Novel Approach for Reducing Hyperoxaluria and Kidney Stone Risk.

Phase 4 Interventional University of Texas Southwestern Medical Center · NCT06481150

This study is testing if the drug Tenapanor can help healthy adults lower the amount of oxalate their bodies absorb from food to reduce the risk of kidney stones.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment10 (estimated)
Ages18 Years to 99 Years
SexAll
SponsorUniversity of Texas Southwestern Medical Center Academic / other
Locations1 site (Dallas, Texas)
Trial IDNCT06481150 on ClinicalTrials.gov

What this trial studies

This pilot study investigates the use of Tenapanor, a drug recently approved for treating hyperphosphatemia, to reduce intestinal absorption of oxalate in healthy adults. Participants will consume a high-oxalate diet while taking either Tenapanor or a placebo in a crossover design. The study aims to measure the impact of Tenapanor on urinary oxalate excretion over two phases, each lasting five days, with a washout period in between. The results could provide insights into a novel approach for managing hyperoxaluria and preventing kidney stones.

Who should consider this trial

Good fit: Ideal candidates for this study are normal, healthy adult volunteers without a history of kidney stones or gastrointestinal diseases.

Not a fit: Patients with a personal history of kidney stones, chronic kidney disease, or gastrointestinal disorders may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could significantly reduce the risk of kidney stones in patients by lowering urinary oxalate levels.

How similar studies have performed: While the approach of using Tenapanor for this purpose is novel, similar studies targeting intestinal absorption have shown promise in related conditions.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Normal, healthy adult volunteers

Exclusion Criteria:

* Personal history of kidney stones
* Pregnant or nursing
* Recurrent urinary tract infections
* Lithogenic urine chemistry at baseline (oxalate \> 45 mg/24 h, urine calcium \> 300 mg/24 h)
* Chronic kidney disease (eGFR \< 90 mL/min/1.73m2)
* Personal history of GI disease, GI obstruction, or GI surgery
* Chronic diarrhea
* Intestinal inflammation (Fecal calprotectin \> 120 mcg/g)
* Drugs which are substrates of OATP2B1 (e.g. enalapril)
* Chronic use of sodium polystyrene sulfonate, angiotensin-converting enzyme inhibitors, diuretics, antacids, alkali treatment, or carbonic anhydrase inhibitors.

Where this trial is running

Dallas, Texas

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Hyperoxaluria
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.