Renal Metabolism of Glycolate to Oxalate

NCT ID: NCT04437225

Last Updated: 2025-12-19

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

ACTIVE_NOT_RECRUITING

Clinical Phase

NA

Total Enrollment

15 participants

Study Classification

INTERVENTIONAL

Study Start Date

2020-03-12

Study Completion Date

2027-09-01

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

This study will determine the contribution of glycolate metabolism to urinary oxalate excretion in healthy subjects, using carbon 13 isotope glycolate tracer technique and a low-oxalate controlled diet.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

It is known that glycolate, an intermediary molecule in normal metabolism, can be converted into oxalate. The origin of urinary oxalate is of interest as calcium oxalate is a main component of kidney stones. In the rare disease primary hyperoxaluria, excessive production of oxalate by the body results in frequent kidney stones and can cause loss of kidney function. Primary hyperoxaluria is caused by deficiencies in one of several enzymes involved in the glycolate pathway.

This study will seek to determine how much oxalate is formed from glycolate in normal subjects. After consuming a controlled diet, subjects will either ingest or have an intravenous infusion of carbon 13 glycolate, a stable isotope of glycolate that can be tracked and will also label downstream metabolic products. Blood and urine samples will be assessed for their amounts of labeled glycolate and labeled oxalate to provide an accurate measure of how much oxalate is made from normal glycolate breakdown in healthy human subjects.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Healthy

Keywords

Explore important study keywords that can help with search, categorization, and topic discovery.

oxalate metabolism kidney stones glycolate isotope tracer study urolithiasis oxalate

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

NON_RANDOMIZED

Intervention Model

SEQUENTIAL

Subject will undergo the gold-standard technique of steady-state intravenous infusion of 13-glycolate administration. Selected subjects will also undergo other modified modalities of 13-glycolate administration.
Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

NONE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Constant Infusion of 13C2-Glycolate

Subjects will consume a controlled diet for 5 days total. On Days 3 and 4, subjects will collect 24 hour urines. On Day 5, they will come to the Clinical Research Unit (CRU) in the fasted state for a visit lasting from 7:00 am to 5:30 pm. An intravenous (IV) catheter will be placed in a vein on the back of the hand at 7:30 am for the carbon 13 glycolate infusion which will occur at a constant rate for 10 hours, following a priming dose. From 7:30 am to 5:30 pm, urine collections will occur hourly, and from 8:30 am to 5:30 pm, IV blood collections will occur every half hour. Subjects will receive a meal at 5:30 pm, thus concluding the CRU visit. At home, subjects will collect timed urine until the next morning to be returned to the CRU.

Group Type EXPERIMENTAL

Low oxalate controlled Diet

Intervention Type DIETARY_SUPPLEMENT

Participants will consume a diet that is controlled in its contents of protein, carbohydrates, fat, calcium, oxalate, vitamin C and sodium. Participants will be asked not to take any dietary supplements, exercise strenuously, or consume food or drink that is not provided to them.

Primed, continuous intravenous infusion of 13C2-Glycolate

Intervention Type OTHER

Participants will receive a continuous intravenous administration of carbon-13 glycolate, a naturally occurring form of glycolate, over the course of several hours until steady-state is achieved, using an IV catheter.

Single Intravenous Dose of 13C2-Glycolate

Subjects will consume a controlled diet for 5 days total. On Days 3 and 4, subjects will collect 24 hour urines. On Day 5, they will come to the Clinical Research Unit (CRU) in the fasted state for a visit lasting from 7:00 am to 2:30 pm. An intravenous (IV) catheter will be placed in a vein on the back of the hand at 8:30 am for a single dose of carbon-13 glycolate to be administered. From 7:30 am to 2:30 pm, urine collections will occur hourly. At 8:30 am, IV blood samples will be taken every fifteen minutes until 9:30 am, every half hour from 9:30 am to 10:30 am, and then finally hourly from 10:30 am to 2:30 pm . Subjects will receive a meal at 2:30 pm, thus concluding the CRU visit. At home, subjects will collect timed urine until the next morning to be returned to the CRU.

Group Type EXPERIMENTAL

Low oxalate controlled Diet

Intervention Type DIETARY_SUPPLEMENT

Participants will consume a diet that is controlled in its contents of protein, carbohydrates, fat, calcium, oxalate, vitamin C and sodium. Participants will be asked not to take any dietary supplements, exercise strenuously, or consume food or drink that is not provided to them.

Bolus intravenous infusion of 13C2-Glycolate

Intervention Type OTHER

Participants will receive a bolus intravenous administration of carbon-13 glycolate, a naturally occurring form of glycolate, using an IV catheter.

Single Oral Dose of 13C2-Glycolate

Subjects will consume a controlled diet for 5 days total. On Days 3 and 4, subjects will collect 24 hour urines. On Day 5, they will come to the Clinical Research Unit (CRU) in the fasted state for a visit lasting from 7:00 am to 2:30 pm. At 8:30 am, subjects will ingest the carbon-13 glycolate, dissolved in to 50 ml (about 1/4 cup) of water. From 7:30 am to 2:30 pm, urine collections will occur hourly. At 8:30 am, intravenous (IV) blood samples will be taken every fifteen minutes until 9:30 am, every half hour from 9:30 am to 10:30 am, and then finally hourly from 10:30 am to 2:30 pm . Subjects will receive a meal at 2:30 pm, thus concluding the CRU visit. At home, subjects will collect timed urine until the next morning to be returned to the CRU.

Group Type EXPERIMENTAL

Low oxalate controlled Diet

Intervention Type DIETARY_SUPPLEMENT

Participants will consume a diet that is controlled in its contents of protein, carbohydrates, fat, calcium, oxalate, vitamin C and sodium. Participants will be asked not to take any dietary supplements, exercise strenuously, or consume food or drink that is not provided to them.

Oral bolus administration of 13C2-Glycolate

Intervention Type OTHER

Participants will orally ingest a single dose of carbon-13 glycolate, a naturally occurring form of glycolate.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Low oxalate controlled Diet

Participants will consume a diet that is controlled in its contents of protein, carbohydrates, fat, calcium, oxalate, vitamin C and sodium. Participants will be asked not to take any dietary supplements, exercise strenuously, or consume food or drink that is not provided to them.

Intervention Type DIETARY_SUPPLEMENT

Primed, continuous intravenous infusion of 13C2-Glycolate

Participants will receive a continuous intravenous administration of carbon-13 glycolate, a naturally occurring form of glycolate, over the course of several hours until steady-state is achieved, using an IV catheter.

Intervention Type OTHER

Bolus intravenous infusion of 13C2-Glycolate

Participants will receive a bolus intravenous administration of carbon-13 glycolate, a naturally occurring form of glycolate, using an IV catheter.

Intervention Type OTHER

Oral bolus administration of 13C2-Glycolate

Participants will orally ingest a single dose of carbon-13 glycolate, a naturally occurring form of glycolate.

Intervention Type OTHER

Other Intervention Names

Discover alternative or legacy names that may be used to describe the listed interventions across different sources.

Constant infusion of 13C2-Glycolate Single intravenous dose of 13C2-Glycolate Single oral dose of 13C2-Glycolate

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Mentally competent adults, able to read and comprehend the consent form
* 18-75 years of age
* Body Mass Index (BMI) between 19 and 40
* In good health as judged from a medical history, reported medications, and a complete blood metabolic profile
* Acceptable 24 hour urine collections (performed twice for screening)

Exclusion Criteria

* History of any hepatic, renal, bowel, or endocrine disease or any other condition that may influence the absorption, transport or urine excretion of ions
* Abnormal urine chemistries or blood metabolic profiles
* Poor 24 hour urine collections completed during screening, judged by 24 hour urine creatinine excretion (indicative of not collecting all urine in the 24 hour period)
* Pregnancy, intention to become pregnant in the near future, or lactation
* Aged \<18 or \>75
* BMI \<19 or \>40
Minimum Eligible Age

18 Years

Maximum Eligible Age

75 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

NIH

Sponsor Role collaborator

University of Alabama at Birmingham

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Sonia Fargue

Principle Investigator

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Sonia Fargue, M.D., Ph.D.

Role: PRINCIPAL_INVESTIGATOR

University of Alabama at Birmingham

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

University of Alabama at Birmingham

Birmingham, Alabama, United States

Site Status

Countries

Review the countries where the study has at least one active or historical site.

United States

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

K01DK114332

Identifier Type: NIH

Identifier Source: secondary_id

View Link

UAB

Identifier Type: OTHER

Identifier Source: secondary_id

IRB160505004-GLI

Identifier Type: -

Identifier Source: org_study_id