Active — Not RecruitingNot Applicable

Oxalate Formation From Ascorbic Acid

United States90 participantsStarted 2021-11-15

Plain-language summary

The purpose of this basic research study is to determine the contribution of endogenous ascorbic acid (AA) turnover to urinary oxalate excretion in both normal BMI and obese adult non-stone formers and calcium oxalate stone formers. The studies proposed will use diets of known nutrient composition, a stable isotope of ascorbic acid (13C6-AA) and mass spectrometric techniques to quantify ascorbic acid turnover to oxalate.

Who can participate

Age range

19 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Able to provide informed consent * For stone formers: composition of most recent stone \> 50% calcium oxalate, no uric acid component * For stone formers: first time or recurrent calcium oxalate stone former with stone event within the prior 3 years * Two 24-hour urine collections with urinary 24-hour creatinine excretion within 20% of appropriate ratio of creatinine (mg) / body weigh (kg) for gender * Willingness to stop supplements (vitamins, Calcium (citrate or carbonate) and other minerals, herbal supplements, nutritional aids, probiotics) for 2 weeks before start and during study * Willingness to not undertake vigorous exercise during the study * Normal fasting blood Comprehensive Metabolic Panel (CMP) * Willingness to ingest menus prepared in Clinical Research Unit at University of Alabama at Birmingham * No food allergies or intolerance to any of the foods in study menus * If on medications for stone prevention (e.g. thiazides, citrate supplementation excluding calcium citrate), they should have been on a stable dose regimen for at least 8 weeks prior to and during screening, with no changes in dosing anticipated during study protocol. If on allopurinol for stone prevention, stop it for 2 weeks prior to screening and this will not be administered during the study as it has anti-oxidant properties. Exclusion Criteria: * Diabetes * Gout * Hypertension * Estimated Glomerular Filtration Rate (eGFR) less than 60ml/min/1.73m2 * Primary hyperoxaluria …

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Percent contribution of ascorbic acid (AA) to urinary oxalate excretion

Timeframe: Day 4

Trial details

NCT IDNCT04603898

SponsorUniversity of Alabama at Birmingham

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2026-12-01

View on ClinicalTrials.gov More Kidney Stone trials