Renal Metabolism of Glycolate to Oxalate

NCT04437225 | Active Not Recruiting DMC

• 3 other identifiers: IRB160505004-GLIK01DK114332UAB
• Study Type: interventional
• Target: 15
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Healthy

Keywords

oxalate metabolism; kidney stones; glycolate; isotope tracer study; urolithiasis; oxalate

Outcome Measures

Primary Outcomes (2)

• Urinary oxalate measured by ion chromatography coupled with mass spectrometry

  Measurement of carbon 13 labeled and unlabeled urinary oxalate following carbon 13 glycolate administration, after equilibration under a low-oxalate diet.

  day 5 of dietary control

• Plasma glycolate measured by ion chromatography coupled with mass spectrometry

  Measurement of carbon 13 labeled and unlabeled plasma glycolate following carbon 13 glycolate administration, after equilibration under a low-oxalate diet.

  day 5 of dietary control

Secondary Outcomes (2)

• Urinary creatinine

  day 5 of dietary control

• Urinary glycolate measured by ion chromatography coupled with mass spectrometry

  day 5 of dietary control

Study Arms (3)

Constant Infusion of 13C2-Glycolate

EXPERIMENTAL

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.

Dietary Supplement: Low oxalate controlled Diet; Other: Primed, continuous intravenous infusion of 13C2-Glycolate

Single Intravenous Dose of 13C2-Glycolate

EXPERIMENTAL

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.

Dietary Supplement: Low oxalate controlled Diet; Other: Bolus intravenous infusion of 13C2-Glycolate

Single Oral Dose of 13C2-Glycolate

EXPERIMENTAL

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.

Dietary Supplement: Low oxalate controlled Diet; Other: Oral bolus administration of 13C2-Glycolate

Interventions

Bolus intravenous infusion of 13C2-Glycolate OTHER

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

Also known as: Single intravenous dose of 13C2-Glycolate

Single Intravenous Dose of 13C2-Glycolate

Oral bolus administration of 13C2-Glycolate OTHER

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

Also known as: Single oral dose of 13C2-Glycolate

Single Oral Dose of 13C2-Glycolate

Low oxalate controlled Diet 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.

Constant Infusion of 13C2-Glycolate; Single Intravenous Dose of 13C2-Glycolate; Single Oral Dose of 13C2-Glycolate

Primed, continuous intravenous infusion of 13C2-Glycolate 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.

Also known as: Constant infusion of 13C2-Glycolate

Constant Infusion of 13C2-Glycolate

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Mentally competent adults, able to read and comprehend the consent form
• 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)

You may not qualify if:

• 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

Sponsors & Collaborators

• University of Alabama at Birmingham: lead
• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): collaborator

Study Sites (1)

University of Alabama at Birmingham

Birmingham, Alabama, 35233, United States

Location

MeSH Terms

Conditions

Kidney Calculi; Urolithiasis

Condition Hierarchy (Ancestors)

Nephrolithiasis; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Urinary Calculi; Male Urogenital Diseases; Calculi; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms

Study Officials

• Sonia Fargue, M.D., Ph.D.

  University of Alabama at Birmingham

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SEQUENTIAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principle Investigator

Model Details: 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.

Study Record Dates

• First Submitted: June 15, 2020
• First Posted: June 18, 2020
• Study Start: March 12, 2020
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): September 1, 2027
• Last Updated: December 19, 2025

Record last verified: 2025-12

Locations

US (1)