Bariatric Surgery CandidateNCT05356000
GI Oxalate Absorption
A study testing Special low-oxalate diet followed by all-day visit to University of Chicago research clinic in people with Bariatric Surgery Candidate and Kidney Stone, run by University of Chicago at 1 site in United States.
Trial summary
This study aims to learn more about how oxalate, a compound found in many foods, may affect a person's chances of forming kidney stones. Active participation in this study will last for around one week. For the first two days, subjects will be asked to eat a special diet at home. Read more about this study
- Who is it for?
- Ages 18 to 70 years
- Conditions the study is for
- Bariatric Surgery Candidate, Kidney Stone
- What is being tested?
- Special low-oxalate diet followed by all-day visit to University of Chicago research clinic
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 1 siteUnited States
- Study dates
- 25 Jan 2023to 2 Aug 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 70 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Post-Roux-en-Y gastric bypass stone formers:
- Age 18-70
- Previous history of Roux-en-Y gastric bypass
- History of at least one calcium-based kidney stone after surgery
- Pre-protocol urine oxalate above the lab normal range (50mg/day)
- Obese stone formers:
Show all 13Show fewer
- Age 18-70
- Body mass index (BMI) >=30kg/m2
- History of at least one calcium-based kidney stone
- Pre-protocol urine oxalate above the lab normal range (50mg/day)
- Non-obese stone formers:
- Age 18-70, BMI between 18.5-29.9 kg/m2
- History of at least one calcium-based kidney stone
Who cannot join
- Post-Roux-en-Y gastric bypass stone formers:
- History of colon resection (partial or complete)
- History of duodenal switch bowel surgery
- History of ileal-jejunal bypass surgery
- History of primarily uric acid, cysteine, or struvite stones
- Obese and non-obese stone formers:
Show all 10Show fewer
- History of bowel surgery
- History of colon resection
- History of inflammatory bowel disease (Crohn's disease, Ulcerative Colitis)
- History of primarily uric acid, cysteine, or struvite stones
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
University of Chicago Medical Center
Chicago, Illinois, 60637
Megan Prochaska, MD, 773-702-1000 ext. 45488, mprocha2@medicine.bsd.uchicago.edu
Megan Prochaska, MD
About this study
Official title: Determine the Contribution of Paracellular GI Oxalate Absorption in Obese and Roux-en-Y Gastric Bypass Kidney Stone Patients
This study aims to learn more about how oxalate, a compound found in many foods, may affect a person's chances of forming kidney stones. Active participation in this study will last for around one week.
For the first two days, subjects will be asked to eat a special diet at home. From Days 3-5, they will eat special meals delivered to their home from a research clinic at the University of Chicago. They will also collect 24-hour urine samples at home on Days 4 and 5. On Day 6, they will come in to the research clinic at the University of Chicago in Hyde Park, where they will spend most of the day. They will receive a special liquid that contains oxalate, and we will have them eat a specially prepared breakfast that is low in oxalate and citrate.
Read the detailed description
The study will be carried out in the University of Chicago Medicine (UCM) Clinical Research Center (CRC).
Study Population and Recruitment Enroll 10 post-Roux-en-Y Gastric Bypass stone forming, 10 obese stone forming, and 10 non-obese stone forming participants over four years of the award. Patients will be recruited at the University of Chicago Kidney Stone Clinic and Bariatric Surgery Clinics (both current and repository of previous patients). The Bariatric Surgery Clinic is a large clinic and Center for Excellence for bariatric surgery. The group's four active surgeons (including study advisor, Dr. John Alverdy) perform 300 bariatric surgeries per year. Over the past 10 years, at least one quarter to one half of these procedures have been Roux-en-Y Gastric Bypass. Incidence rates for stones at 10 years after Roux-en-Y Gastric Bypass is 14% and thus, even with conservative estimates, we will have over 100 eligible patients from this clinic.
Experimental Design and Implications Administration of very low oxalate diet (50mg/day) for three days followed by 13c2-oxalate and sucralose oral load test will determine the amount of oxalate absorbed via gastrointestinal (GI) paracellular pathways discriminated from endogenous oxalate production. Urine oxalate levels after low oxalate diet will provide an estimate of GI oxalate absorption combined with hepatic production (Aim 2a). By measuring the proportion of 13c2-oxalate load that appears in the urine, we will determine the fraction of absorbed oxalate that appears in the urine. Sucralose will be used with the load test as a marker of paracellular transport. Sucralose is an artificial sweetener that is absorbed in the GI tract via paracellular pathways and excreted unchanged in the urine. It is used to estimate permeability of the whole GI tract and as a marker of paracellular GI transport. Along with 13c2-oxalate, sucralose has been used to study GI oxalate transport mechanisms.
The knowledge obtained from these studies will determine the contribution of GI absorption of dietary oxalate and how it is absorbed from the GI tract. These data will provide crucial information to understanding mechanisms for stone risk in obese and Roux-en-Y Gastric Bypass stone formers. If high urine oxalate in Roux-en-Y Gastric Bypass and obese stone forming is primarily due to GI hyperabsorption, then a low oxalate diet will not decrease urine oxalate levels and levels will decrease less in obese and Roux-en-Y Gastric Bypass stone formers than non-obese stone formers. This will potentially reset the clinical utility of a low oxalate diet in these patients. If high urine oxalate is from GI paracellular hyperabsorption, then the percent absorption of 13c2-oxalate and sucralose will be greater in obese and post-Roux-en-Y Gastric Bypass stone formers compared with non-obese stone formers. Follow up studies will focus on how to block or blunt this mechanism. If high urine oxalate in obese and Roux-en-Y Gastric Bypass stone forming is due to other oxalate sources (i.e. endogenous production) then the percent absorption of 13c2-oxalate and sucralose will not be greater in obese and Roux-en-Y Gastric Bypass stone formers compared with non-obese stone formers. Clinically, this will direct patients and physicians towards higher impact management strategies with less emphasis on a low oxalate diet. Future studies will investigate endogenous production of oxalate in obese and Roux-en-Y Gastric Bypass stone formers. Better strategies for oxalate management after surgery will lower kidney stone risk in these high-risk patients and lower the risk of chronic kidney disease progression and end-stage renal disease that can result from high urine oxalate.
In non-obese stone formers (N=10) obese stone formers (N=10) and post-Roux-en-Y Gastric Bypass stone formers (N=10), we will measure urine oxalate and citrate before and after three days of low (50mg/day) oxalate diet. Primary endpoint (hypothesis 2a) is change in urine oxalate excretion from baseline after low oxalate diet in non-obese versus obese and Roux-en-Y Gastric Bypass stone formers. 2b and 2c: Following the low oxalate diet, give a 13c2-labeled sodium oxalate (100mg) and sucralose (5g) oral load test and measure urine oxalate, citrate, and sucralose over 24 hours. Primary endpoint (hypothesis 2b) is percent 13c2-oxalate of total administered in non-obese versus obese and Roux-en-Y Gastric Bypass stone formers. Secondary endpoint (hypothesis 2c) is percent sucralose of total administered in non-obese versus obese and Roux-en-Y Gastric Bypass stone formers.
Rationale: Absorption of diet oxalate may be elevated in obese and post-Roux-en-Y Gastric Bypass stone formers, however the actual contribution of increased gastrointestinal (GI) oxalate absorption to hyperoxaluria in these patients has not been documented. It is also unclear what proportion of oxalate is absorbed via the paracellular route. If an increase in GI oxalate absorption is not sufficient to explain hyperoxaluria, it would change treatment of these patients.
- Conditions
- Bariatric Surgery Candidate, Kidney Stone
- Being tested
- Special low-oxalate diet followed by all-day visit to University of Chicago research clinic
- Keywords
- Roux-en-Y Gastric Bypass, RYGB, Oxalate
- Medical subject headings
- Kidney Calculi
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Special low-oxalate diet followed by all-day visit to University of Chicago research clinicOther
Active participation in this study will last for around one week. For the first two days, participants will be asked to eat a special diet at home. From Days 3-5, they will eat special meals that will be delivered to their home from a research clinic at the University of Chicago. They will also collect urine at home on Days 4 and 5.
On Day 6, subjects will come in to the research clinic at the University of Chicago in Hyde Park, where they will spend most of the day. They will receive a special liquid that contains oxalate, and will receive a specially prepared breakfast that is low in oxalate and citrate. After this, we will collect their urine and blood throughout the day. We will draw blood 4 separate times.
| Study group | Role | What they receive |
|---|---|---|
| Subjects who will follow low-oxalate diet followed by visit to research clinic | Other | 30 stone-forming participants will be recruited to this study. Receives: Other: Special low-oxalate diet followed by all-day visit to University of Chicago research clinic |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in 24-hour urine oxalate from baseline to after 5 days on low oxalate diet (2 days on participant managed, 3 days on clinical research center prepared diet of 50mg/day)
24-hour urine oxalate will be measured before and after participants follow a low oxalate diet for 5 total days (3 days will be clinical research center prepared food with known measured oxalate content of 50mg/day)
Measured: 6 days
Percent absorption of 13C2-oxalate from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Measured: 6 days
Change in urine 13C2-oxalate from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Measured: 6 days
Percent absorption total urine oxalate from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Measured: 6 days
Percent absorption of sucralose from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Measured: 6 days
Change in urine sucralose from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Measured: 6 days
Secondary outcomes (1)
Compare change in urine oxalate levels from baseline to post-low oxalate diet between the three groups: lean kidney stone patients, obese kidney stone patients, and post- Roux-en-Y gastric bypass kidney stone patients
- 24-hour urine oxalate will be measured before and after participants follow a low oxalate diet for 5 total days (3 days will be clinical research center prepared food with known measured oxalate content of 50mg/day).
Measured: 6 days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 May 2022
- Study start25 Jan 2023
- Primary completion2 Jun 2026 (estimated)
- Study completion2 Aug 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Bariatric Surgery CandidateStudies of the same condition, open and under way.
- More trials run by University of ChicagoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Chicago
- Sponsor type
- University, hospital or other
- Collaborators
- University of Alabama at Birmingham
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05356000
- Sponsor's protocol ID
- IRB22-0023
- Status last verified
- Aug 2025
- First submitted
- 26 Apr 2022
- Last updated
- 19 Aug 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 19 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Determine the Contribution of Paracellular GI Oxalate Absorption in Obese and Roux-en-Y Gastric Bypass Kidney Stone Patients
- ClinicalTrials.gov ID
- NCT05356000
- Acronym / sponsor ID
- IRB22-0023
- Conditions
- Bariatric Surgery Candidate, Kidney Stone
- Keywords
- Roux-en-Y Gastric Bypass, RYGB, Oxalate
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- University of ChicagoUniversity, hospital or other
- Collaborators
- University of Alabama at Birmingham
- Study start
- 25 Jan 2023 (actual)
- Primary completion
- 2 Jun 2026 (estimated)
- Study completion
- 2 Aug 2026 (estimated)
- First posted
- 2 May 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to learn more about how oxalate, a compound found in many foods, may affect a person's chances of forming kidney stones. Active participation in this study will last for around one week.
For the first two days, subjects will be asked to eat a special diet at home. From Days 3-5, they will eat special meals delivered to their home from a research clinic at the University of Chicago. They will also collect 24-hour urine samples at home on Days 4 and 5. On Day 6, they will come in to the research clinic at the University of Chicago in Hyde Park, where they will spend most of the day. They will receive a special liquid that contains oxalate, and we will have them eat a specially prepared breakfast that is low in oxalate and citrate.
Detailed description
The study will be carried out in the University of Chicago Medicine (UCM) Clinical Research Center (CRC).
Study Population and Recruitment Enroll 10 post-Roux-en-Y Gastric Bypass stone forming, 10 obese stone forming, and 10 non-obese stone forming participants over four years of the award. Patients will be recruited at the University of Chicago Kidney Stone Clinic and Bariatric Surgery Clinics (both current and repository of previous patients). The Bariatric Surgery Clinic is a large clinic and Center for Excellence for bariatric surgery. The group's four active surgeons (including study advisor, Dr. John Alverdy) perform 300 bariatric surgeries per year. Over the past 10 years, at least one quarter to one half of these procedures have been Roux-en-Y Gastric Bypass. Incidence rates for stones at 10 years after Roux-en-Y Gastric Bypass is 14% and thus, even with conservative estimates, we will have over 100 eligible patients from this clinic.
Experimental Design and Implications Administration of very low oxalate diet (50mg/day) for three days followed by 13c2-oxalate and sucralose oral load test will determine the amount of oxalate absorbed via gastrointestinal (GI) paracellular pathways discriminated from endogenous oxalate production. Urine oxalate levels after low oxalate diet will provide an estimate of GI oxalate absorption combined with hepatic production (Aim 2a). By measuring the proportion of 13c2-oxalate load that appears in the urine, we will determine the fraction of absorbed oxalate that appears in the urine. Sucralose will be used with the load test as a marker of paracellular transport. Sucralose is an artificial sweetener that is absorbed in the GI tract via paracellular pathways and excreted unchanged in the urine. It is used to estimate permeability of the whole GI tract and as a marker of paracellular GI transport. Along with 13c2-oxalate, sucralose has been used to study GI oxalate transport mechanisms.
The knowledge obtained from these studies will determine the contribution of GI absorption of dietary oxalate and how it is absorbed from the GI tract. These data will provide crucial information to understanding mechanisms for stone risk in obese and Roux-en-Y Gastric Bypass stone formers. If high urine oxalate in Roux-en-Y Gastric Bypass and obese stone forming is primarily due to GI hyperabsorption, then a low oxalate diet will not decrease urine oxalate levels and levels will decrease less in obese and Roux-en-Y Gastric Bypass stone formers than non-obese stone formers. This will potentially reset the clinical utility of a low oxalate diet in these patients. If high urine oxalate is from GI paracellular hyperabsorption, then the percent absorption of 13c2-oxalate and sucralose will be greater in obese and post-Roux-en-Y Gastric Bypass stone formers compared with non-obese stone formers. Follow up studies will focus on how to block or blunt this mechanism. If high urine oxalate in obese and Roux-en-Y Gastric Bypass stone forming is due to other oxalate sources (i.e. endogenous production) then the percent absorption of 13c2-oxalate and sucralose will not be greater in obese and Roux-en-Y Gastric Bypass stone formers compared with non-obese stone formers. Clinically, this will direct patients and physicians towards higher impact management strategies with less emphasis on a low oxalate diet. Future studies will investigate endogenous production of oxalate in obese and Roux-en-Y Gastric Bypass stone formers. Better strategies for oxalate management after surgery will lower kidney stone risk in these high-risk patients and lower the risk of chronic kidney disease progression and end-stage renal disease that can result from high urine oxalate.
In non-obese stone formers (N=10) obese stone formers (N=10) and post-Roux-en-Y Gastric Bypass stone formers (N=10), we will measure urine oxalate and citrate before and after three days of low (50mg/day) oxalate diet. Primary endpoint (hypothesis 2a) is change in urine oxalate excretion from baseline after low oxalate diet in non-obese versus obese and Roux-en-Y Gastric Bypass stone formers. 2b and 2c: Following the low oxalate diet, give a 13c2-labeled sodium oxalate (100mg) and sucralose (5g) oral load test and measure urine oxalate, citrate, and sucralose over 24 hours. Primary endpoint (hypothesis 2b) is percent 13c2-oxalate of total administered in non-obese versus obese and Roux-en-Y Gastric Bypass stone formers. Secondary endpoint (hypothesis 2c) is percent sucralose of total administered in non-obese versus obese and Roux-en-Y Gastric Bypass stone formers.
Rationale: Absorption of diet oxalate may be elevated in obese and post-Roux-en-Y Gastric Bypass stone formers, however the actual contribution of increased gastrointestinal (GI) oxalate absorption to hyperoxaluria in these patients has not been documented. It is also unclear what proportion of oxalate is absorbed via the paracellular route. If an increase in GI oxalate absorption is not sufficient to explain hyperoxaluria, it would change treatment of these patients.
Study design
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Subjects who will follow low-oxalate diet followed by visit to research clinic | Other | Other: Special low-oxalate diet followed by all-day visit to University of Chicago research clinic30 stone-forming participants will be recruited to this study. |
Who may qualify
- Ages
- 18 to 70 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (13 listed)
- Age 18-70
- Previous history of Roux-en-Y gastric bypass
- History of at least one calcium-based kidney stone after surgery
- Pre-protocol urine oxalate above the lab normal range (50mg/day)
- Age 18-70
Key exclusion criteria (10 listed)
- History of colon resection (partial or complete)
- History of duodenal switch bowel surgery
- History of ileal-jejunal bypass surgery
- History of primarily uric acid, cysteine, or struvite stones
- History of bowel surgery
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Special low-oxalate diet followed by all-day visit to University of Chicago research clinicActive participation in this study will last for around one week. For the first two days, participants will be asked to eat a special diet at home. From Days 3-5, they will eat special meals that will be delivered to their home from a research clinic at the University of Chicago. They will also collect urine at home on Days 4 and 5. On Day 6, subjects will come in to the research clinic at the University of Chicago in Hyde Park, where they will spend most of the day. They will receive a special liquid that contains oxalate, and will receive a specially prepared breakfast that is low in oxalate and citrate. After this, we will collect their urine and blood throughout the day. We will draw blood 4 separate times. | Other | Subjects who will follow low-oxalate diet followed by visit to research clinic |
Primary outcome
Change in 24-hour urine oxalate from baseline to after 5 days on low oxalate diet (2 days on participant managed, 3 days on clinical research center prepared diet of 50mg/day)
Time frame: 6 days
24-hour urine oxalate will be measured before and after participants follow a low oxalate diet for 5 total days (3 days will be clinical research center prepared food with known measured oxalate content of 50mg/day)
Percent absorption of 13C2-oxalate from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Time frame: 6 days
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Change in urine 13C2-oxalate from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Time frame: 6 days
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Percent absorption total urine oxalate from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Time frame: 6 days
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Percent absorption of sucralose from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Time frame: 6 days
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
Change in urine sucralose from pre-load baseline (time 0) to 2, 4-, 6-, and 24-hour time points
Time frame: 6 days
Will be measured or calculated at time points 0, 2-hours, 4-hours, 6-hours and 24-hours after sodium 13C2-oxalate and sucralose consumption. We will compare change in urine total urine oxalate and 13C2-oxalate/total oxalate and sucralose each time period for all participants.
1 secondary outcome
Compare change in urine oxalate levels from baseline to post-low oxalate diet between the three groups: lean kidney stone patients, obese kidney stone patients, and post- Roux-en-Y gastric bypass kidney stone patients
Time frame: 6 days
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 Aug 2025.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Special low-oxalate diet followed by all-day visit to University of Chicago research clinic in people with Bariatric Surgery Candidate and Kidney Stone, run by University of Chicago at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 13 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 19 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Megan Prochaska, MD (773-702-1000 ext. 45488, mprocha2@medicine.bsd.uchicago.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in 24-hour urine oxalate from baseline to after 5 days on low oxalate diet (2 days on participant managed, 3 days on clinical research center prepared diet of 50mg/day) (time frame: 6 days). The study lists 6 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 Aug 2025.