NCT06481150

Brief Summary

This pilot study is proposing a novel approach to directly target intestinal oxalate absorption with the drug Tenapanor, which was recently FDA-approved for treating hyperphosphatemia in patients with chronic kidney disease. Tenapanor works by blocking paracellular phosphate absorption by the intestine, but the underlying mechanisms have not been clearly defined. Since phosphate and oxalate ions are absorbed through the same paracellular pathway, and are of similar size and charge, Tenapanor is hypothesized to also reduce dietary oxalate absorption and consequently lower urinary oxalate excretion.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
18

participants targeted

Target at below P25 for phase_4

Timeline
Completed

Started Jul 2024

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

June 24, 2024

Completed
7 days until next milestone

First Posted

Study publicly available on registry

July 1, 2024

Completed
Same day until next milestone

Study Start

First participant enrolled

July 1, 2024

Completed
1.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 14, 2025

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

September 14, 2025

Completed
Last Updated

February 6, 2026

Status Verified

February 1, 2026

Enrollment Period

1.2 years

First QC Date

June 24, 2024

Last Update Submit

February 3, 2026

Conditions

Hyperoxaluria

Outcome Measures

Primary Outcomes (1)

  • 24-h urine oxalate

    Study participants collect two 24-hour urine specimens for analysis of their stone-risk profile, including oxalate (mg/24 h), comparing placebo with drug treatment (Tenapanor).

    Two 24-h urine on days 4 and 5 of each arm

Study Arms (2)

Tenapanor

EXPERIMENTAL

30 mg Tenapanor twice a day

Drug: Tenapanor

Placebo

PLACEBO COMPARATOR

30 mg Placebo twice a day

Other: Placebo

Interventions

TenapanorDRUG

Each tablet 30 mg

Also known as: XPHOZAH, IBSRELA
Tenapanor
PlaceboOTHER

Placebo

Placebo

Eligibility Criteria

Age18 Years - 99 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Normal, healthy adult volunteers

You may not qualify if:

  • 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.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

UT Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

Related Publications (1)

  • King AJ, Siegel M, He Y, Nie B, Wang J, Koo-McCoy S, Minassian NA, Jafri Q, Pan D, Kohler J, Kumaraswamy P, Kozuka K, Lewis JG, Dragoli D, Rosenbaum DP, O'Neill D, Plain A, Greasley PJ, Jonsson-Rylander AC, Karlsson D, Behrendt M, Stromstedt M, Ryden-Bergsten T, Knopfel T, Pastor Arroyo EM, Hernando N, Marks J, Donowitz M, Wagner CA, Alexander RT, Caldwell JS. Inhibition of sodium/hydrogen exchanger 3 in the gastrointestinal tract by tenapanor reduces paracellular phosphate permeability. Sci Transl Med. 2018 Aug 29;10(456):eaam6474. doi: 10.1126/scitranslmed.aam6474.

    PMID: 30158152BACKGROUND

MeSH Terms

Conditions

Hyperoxaluria

Interventions

tenapanor

Condition Hierarchy (Ancestors)

Kidney DiseasesUrologic DiseasesFemale Urogenital DiseasesFemale Urogenital Diseases and Pregnancy ComplicationsUrogenital DiseasesMale Urogenital Diseases

Study Officials

  • Jonathan M Whittamore, Ph.D.

    University of Texas Southwestern Medical Center

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
phase 4
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
BASIC SCIENCE
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Assistant Professor

Study Record Dates

First Submitted

June 24, 2024

First Posted

July 1, 2024

Study Start

July 1, 2024

Primary Completion

September 14, 2025

Study Completion

September 14, 2025

Last Updated

February 6, 2026

Record last verified: 2026-02

Data Sharing

IPD Sharing
Will not share

Locations

US(1)