Trial Outcomes & Findings for Oxalobacter Formigenes Colonization and Urinary Oxalate Excretion (NCT NCT03752684)

Last Updated: 2026-01-30

Results Overview

Mean 24-hour urine oxalate excretion after colonization with O.formigenes was compared with mean 24-hour urine oxalate before colonization

Recruitment status

COMPLETED

Study phase

Target enrollment

26 participants

Primary outcome timeframe

4 days

Results posted on

2026-01-30

Participants were recruited within the Greater Birmingham area

Participant milestones
Measure	Colonization With Oxalobacter Formigenes Moderately high oxalate/low calcium diet non-colonized: Participants not colonized with O. formigenes will be instructed to ingest the controlled diet and collect 24-hour urines to measure oxalate excretion Oxalobacter formigenes: Participants will then ingest a live preparation of O. formigenes Moderately high oxalate/low calcium diet colonized: Participants successfully colonized with O. formigenes will be instructed to ingest the same controlled diet consumed prior to colonization
Overall Study STARTED	26
Overall Study COMPLETED	22
Overall Study NOT COMPLETED	4

Reasons for withdrawal
Measure	Colonization With Oxalobacter Formigenes Moderately high oxalate/low calcium diet non-colonized: Participants not colonized with O. formigenes will be instructed to ingest the controlled diet and collect 24-hour urines to measure oxalate excretion Oxalobacter formigenes: Participants will then ingest a live preparation of O. formigenes Moderately high oxalate/low calcium diet colonized: Participants successfully colonized with O. formigenes will be instructed to ingest the same controlled diet consumed prior to colonization
Overall Study Lost to Follow-up	4

Oxalobacter Formigenes Colonization and Urinary Oxalate Excretion

Baseline characteristics by cohort
Measure	Colonization With Oxalobacter Formigenes n=22 Participants Moderately high oxalate/low calcium diet non-colonized: Participants not colonized with O.formigenes will collect 24-hour urines on the controlled diet Oxalobacter formigenes: Participants will ingest live preparation of O. formigenes Moderately high oxalate/low calcium diet colonized: Participants successfully colonized with O.formigenes will collect 24-hour urines on the same controlled diet
Age, Categorical <=18 years	0 Participants n=35 Participants
Age, Categorical Between 18 and 65 years	22 Participants n=35 Participants
Age, Categorical >=65 years	0 Participants n=35 Participants
Sex: Female, Male Female	10 Participants n=35 Participants
Sex: Female, Male Male	12 Participants n=35 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=35 Participants
Race (NIH/OMB) Asian	1 Participants n=35 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=35 Participants
Race (NIH/OMB) Black or African American	8 Participants n=35 Participants
Race (NIH/OMB) White	13 Participants n=35 Participants
Race (NIH/OMB) More than one race	0 Participants n=35 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=35 Participants
Region of Enrollment United States	22 participants n=35 Participants
Body Mass Index	29 kg per m2 STANDARD_DEVIATION 5 • n=35 Participants

Timeframe: 4 days

Mean 24-hour urine oxalate excretion after colonization with O.formigenes was compared with mean 24-hour urine oxalate before colonization

Outcome measures
Measure	Colonization With Oxalobacter Formigenes n=22 Participants Moderately high oxalate/low calcium diet non-colonized: Participants not colonized with O.formigenes will collect 24 urines on the controlled diet Oxalobacter formigenes: Participants will ingest live preparation of O. formigenes Moderately high oxalate/low calcium diet colonized: Participants successfully colonized with O.formigenes will collect 24 urines on the controlled diet
Percent Decrease in Urinary Oxalate Excretion After Colonization With O.Formigenes	14 Percentage decrease in urinary oxalate Interval -12.0 to 46.0

Timeframe: 4 days

Mean stool oxalate content after colonization with O.formigenes was compared with mean stool oxalate before colonization

Outcome measures
Measure	Colonization With Oxalobacter Formigenes n=22 Participants Moderately high oxalate/low calcium diet non-colonized: Participants not colonized with O.formigenes will collect 24 urines on the controlled diet Oxalobacter formigenes: Participants will ingest live preparation of O. formigenes Moderately high oxalate/low calcium diet colonized: Participants successfully colonized with O.formigenes will collect 24 urines on the controlled diet
Percentage Decrease in Stool Oxalate Content After Colonization With O.Formigenes	54 Percentage decrease in stool oxalate Interval 1.0 to 93.0

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Adverse event data not reported

Adverse event data not reported

University of Alabama at Birmingham

Phone: 205-996-2295