Back to search results

O. Formigenes Colonization for Calcium Oxalate Kidney Stones

This study is looking at whether introducing a specific gut bacteria, *Oxalobacter formigenes*, can help people who form calcium oxalate kidney stones. Researchers want to see if this bacteria can reduce the amount of oxalate (a substance that can form stones) in your urine. You might be able to join if you are an adult between 18 and 70 years old, have a history of calcium oxalate kidney stones, and do not already have *Oxalobacter formigenes* in your gut. The main goal is to measure changes in your urinary oxalate levels two months after you receive the *Oxalobacter formigenes* treatment. The study is currently recruiting 40 participants.

Study design
This is an interventional study planning to enroll 40 participants. It involves specific dietary interventions and colonization with *Oxalobacter formigenes*.
What's involved
You will ingest fixed diets (low and moderately high oxalate) for 4 days at a time, collect urine, blood, and stool samples, and ingest live *Oxalobacter formigenes*.
Compensation
Not stated in the trial record.
Follow-up
Your urinary oxalate excretion will be measured at 2 months after colonization.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.

NCT06330246

O. Formigenes Colonization in Calcium Oxalate Kidney Stone Disease

Recruiting
NAAges 18–70InterventionalBasic science
University of Alabama at Birmingham
~40 participants
Updated 2026-08-27 on ClinicalTrials.gov
What's tested:Low oxalate fixed diets pre-colonizationModerately high oxalate fixed diets pre-colonizationColonization with Oxalobacter formigenesLow oxalate fixed diets post-colonizationModerately high oxalate fixed diets post-colonization

At a glance

Recruiting sites
2 of 2 listed sites are recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Change in urinary oxalate excretion following colonization with Oxalobacter formigenes
Measured over 2 months

Conditions

Kidney Stone
Kidney Calculi
Urolithiasis
Urolithiasis, Calcium Oxalate
Nephrolithiasis
Nephrolithiasis, Calcium Oxalate
Oxalate Urolithiasis
Oxaluria

Explore related trials

Nephrolithiasis

Where it's being run

2 sites across 2 states
Alabama1
Texas1

Study leadership

  • Sonia Fargue, PhD · PRINCIPAL_INVESTIGATOR · University of Alabama at Birmingham

Who to contact

Sonia Fargue, PhD
[email protected]
2059756932
Email the study team

Opens a ready-to-send draft in your own email app — review before sending.

Do you actually qualify for this trial?

Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.

Check eligibility for this trial ~2 min · HIPAA-protected · delete anytime
Eligibility criteria

Inclusion

age 19-70 yrs
Body Mass Index \> 18.5 kg/m2
First time or recurrent Calcium Oxalate stone former. Composition of most recent stone ≥ 50% calcium oxalate if available
Not colonized with Oxalobacter formigenes
Normal fasting serum electrolytes on comprehensive metabolic profile
Willing to ingest fixed diets
Willing to stop supplements (vitamins including vitamin C, calcium (citrate or carbonate) and other minerals, herbal supplements, nutritional aids, probiotics) for 2 weeks before start and during fixed diet phases.
If on medications for stone prevention (e.g. thiazides, citrate, allopurinol), stable dose regimen for at least 2 weeks prior to and during study

Exclusion

Chronic Kidney Disease stage 4-5
Primary hyperoxaluria
Liver, endocrine or renal diseases (other than idiopathic Calcium Oxalate kidney stones) or any other condition that may influence the absorption, transport or urinary excretion of ions, which will compromise the interpretation of results, including: Cystic fibrosis, Cystinuria, Uric acid stone former, Nephrotic syndrome, Sarcoidosis, Renal tubular acidosis, Primary hyperparathyroidism, Neurogenic bladder, Urinary diversion
Pregnancy or breast-feeding
Incompatible dietary requirements with the study, food allergies or intolerance to any of the foods in study menus
Active malignancy or treatment for malignancy within 12 months prior to screening
Utilization of immunosuppressive medication
Uncontrolled Hypertension or diabetes
Diabetes type 1
Current Colonization with Oxalobacter formigenes

What this trial measures

  • Change in urinary oxalate excretion following colonization with Oxalobacter formigenes2 months

    Difference between urinary oxalate excretion on the moderately high oxalate diet pre-colonization and urinary oxalate excretion on the moderately high oxalate diet post-colonization