NCT04333745

Brief Summary

The primary goals of this study are to determine the contribution of dietary oxalate absorption, renal oxalate handling, and endogenous oxalate synthesis to urinary oxalate excretion in normal Body Mass Index (BMI) and obese calcium oxalate kidney stone formers.

Trial Health

75
On Track

Trial Health Score

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

Enrollment
22

participants targeted

Target at below P25 for not_applicable

Timeline
6mo left

Started Sep 2021

Longer than P75 for not_applicable

Geographic Reach
1 country

2 active sites

Status
active not recruiting

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

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress91%
Sep 2021Dec 2026

First Submitted

Initial submission to the registry

April 1, 2020

Completed
2 days until next milestone

First Posted

Study publicly available on registry

April 3, 2020

Completed
1.4 years until next milestone

Study Start

First participant enrolled

September 1, 2021

Completed
4.9 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 1, 2026

Expected
4 months until next milestone

Study Completion

Last participant's last visit for all outcomes

December 1, 2026

Last Updated

March 9, 2026

Status Verified

March 1, 2026

Enrollment Period

4.9 years

First QC Date

April 1, 2020

Last Update Submit

March 6, 2026

Conditions

Kidney Stone

Keywords

oxalatekidney stone

Outcome Measures

Primary Outcomes (1)

  • Urinary Oxalate Excretion

    Urinary oxalate excretion from urine samples will be measured as mg/day

    Baseline through Day 5

Study Arms (1)

Controlled Dietary Study

EXPERIMENTAL

Participants will consume the controlled diet for five days. After one day on the diet, subjects will provide three 24-hour urine collections. On the last dayof the diet, subjects will come in a fasted state to ingest a small amount of carbon-13 oxalate and sucralose, with hourly urine collections and blood samples being taken before and after the ingestion.

Other: Controlled DietDietary Supplement: Carbon-13 Oxalate and Sucralose Ingestion

Interventions

Controlled DietOTHER

Participant will consume a controlled low oxalate diet for five days

Controlled Dietary Study
Carbon-13 Oxalate and Sucralose IngestionDIETARY_SUPPLEMENT

Subjects will ingest a small amount of carbon-13 oxalate and sucralose, dissolved in water.

Controlled Dietary Study

Eligibility Criteria

Age19 Years - 75 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Normal Body Mass Index (≥ 18.5 to \< 25); Obese Body Mass Index (≥ 30 to ≤ 45)
  • Able to provide informed consent
  • Willingness to consume controlled diet
  • Composition of most recent stone \> 50% calcium oxalate, no uric acid component
  • First time or recurrent calcium oxalate stone former
  • hour urine collections with creatinine values within 20% of appropriate ratio of creatinine (mg)/body weight (kg) for gender, and with creatinine values that are consistent between collections (within 20% of each other)
  • Willingness to stop supplements \[vitamins, Ca (citrate or carbonate) and other minerals, herbal supplements, nutritional aids, probiotics\] for 14 days before start and during study
  • Willingness to not undertake vigorous exercise during the controlled dietary study
  • Normal fasting blood Comprehensive Metabolic Panel
  • Hemoglobin A1c \< 6.5%
  • No food allergies or intolerance to any of the food in study menus
  • Permitted/willing to discontinue medications for kidney stone prevention, including thiazides, allopurinol, and febuxostat and citrate preparations, for 14 days before start and during the studies. They will be instructed to restart these medications at the conclusion of the study

You may not qualify if:

  • Diabetes
  • Abnormal fasting comprehensive metabolic panel (CMP)
  • Hemoglobin A1c (HbA1c) result ≥ 6.5%
  • Gout
  • Estimated Glomerular Filtration Rate (eGFR) \<60 ml/min/1.73m\^2
  • Primary hyperoxaluria
  • Cystic fibrosis
  • Cystinuria
  • Uric acid stone former
  • Utilization of immunosuppressive medication
  • Nephrotic syndrome
  • Enteric hyperoxaluria
  • Gastrointestinal disorder that could impact oxalate transport
  • Sarcoidosis
  • Uncontrolled hypertension
  • +16 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (2)

University of Alabama at Birmingham

Birmingham, Alabama, 35243-3353, United States

Location

University of Texas Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

MeSH Terms

Conditions

Kidney Calculi

Condition Hierarchy (Ancestors)

NephrolithiasisKidney DiseasesUrologic DiseasesFemale Urogenital DiseasesFemale Urogenital Diseases and Pregnancy ComplicationsUrogenital DiseasesUrolithiasisUrinary CalculiMale Urogenital DiseasesCalculiPathological Conditions, AnatomicalPathological Conditions, Signs and Symptoms

Study Officials

  • Dean Assimos, MD

    University of Alabama at Birmingham

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
BASIC SCIENCE
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

April 1, 2020

First Posted

April 3, 2020

Study Start

September 1, 2021

Primary Completion (Estimated)

August 1, 2026

Study Completion (Estimated)

December 1, 2026

Last Updated

March 9, 2026

Record last verified: 2026-03

Locations

US(2)