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Safety, Tolerability and Host Response to Lactobacillus Johnsonii

Safety, Tolerability and Host Response to Lactobacillus Johnsonii

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02349360
Acronym
LJ
Enrollment
42
Registered
2015-01-28
Start date
2015-08-31
Completion date
2016-12-31
Last updated
2018-06-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy

Keywords

safety, tolerability

Brief summary

The purpose of this research study is to determine the effects of the probiotic, Lactobacillus johnsonii N6.2, on safety, gastrointestinal function, wellness, fecal bacteria and blood biomarkers in healthy individuals.

Detailed description

Healthy adult volunteers from 18-50 years of age will be recruited through the University of Florida and randomly distributed into two groups. This study is divided into 3 phases: baseline, intervention (study treatment) and washout. Participants will receive either the probiotic or placebo during the intervention phases. During the baseline phase, blood and fecal samples will be collected about 1 week before intervention initiation. On the day of a scheduled blood draw, the participant will need to arrive fasted overnight, and a light breakfast will be provided after blood draw. Starting on day 1 of the intervention phase, a second baseline blood sample will be collected and the participant will begin the study intervention (probiotic or placebo). Participants will consume 1 capsule (probiotic or placebo) daily for 8 weeks, and blood and stool samples will be collected and processed (on or around weeks 2, 4 and 8 of the intervention phase). A Fisher Scientific commode specimen collection system will be provided for stool collections. The stool collection kit may be taken home (participants will be asked to drop off the stool within 4 hours of defecation) for fecal sample collection or may use the restroom in the clinical lab at the Food Science and Human Nutrition Building in which kits will be provided for use. In the wash-out phase, participants will not consume the capsule (either the probiotic or placebo), but will provide blood and stool samples (on or around week 12). Throughout the study, participants will provide a total of 5 stool samples and 6 blood samples. Participants will be asked to complete daily and weekly questionnaires throughout all phases of the study, which will ask about quality of life (physical functioning, mental functioning, level of sleep, etc.), gastrointestinal function, and dietary intake. These assessments will be self-reported via online questionnaires. In the event that internet access is not available for a portion of the study, paper copies of the questionnaires may be provided.

Interventions

BIOLOGICALL. johnsonii N6.2

L. johnsonii N6.2 10\^10 CFU in capsule form administered for 8 weeks

BIOLOGICALPlacebo

Encapsulated starch placebo administered for 8 weeks

Sponsors

Juvenile Diabetes Research Foundation
CollaboratorOTHER
University of Florida
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes

Inclusion criteria

* To participate in the study individuals must * be 18-50 years old. * be willing to complete multiple questionnaires via computer. * be willing to take the probiotic or placebo capsule daily for 8 weeks. * be willing to provide 1 stool during weeks 0, 2, 4, 8 and 12 of the study. * be willing to provide blood samples at weeks -1, 0, 2, 4, 8 and 12 of the study. * have daily access to a computer with internet access for the entire 13-wk study. * be willing to provide a social security number

Exclusion criteria

* To participate in the study individuals must NOT * currently take medications for constipation, diarrhea or psychological disorders (depression, anxiety, insomnia etc.). * have taken antibiotics within the past four weeks prior to randomization. * currently take probiotic supplements and do not want to discontinue a minimum of two weeks prior to the study * have had or are currently being treated for any diseases or illnesses such as gastrointestinal disease (gastric ulcers, Crohn's, ulcerative colitis, etc.), chronic disease like diabetes or kidney disease, immune-compromising diseases or conditions (HIV, AIDS, hepatitis, cancer, transplant patient etc.) * currently receive medical treatment for stress induced symptoms/disorders * be a current smoker

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants Reporting Adverse Events13 weeksThe number of participants reporting Adverse Events was reported.

Secondary

MeasureTime frameDescription
Composite Measure of Blood Chemistry Profiles13 weeksNumber of clinically relevant out of range values of the comprehensive metabolic panel and hemogram during intervention through washout period vs baseline.

Countries

United States

Participant flow

Participants by arm

ArmCount
Probiotic
L. johnsonii N6.2 10\^10 CFU in capsule form administered for 8 weeks L. johnsonii N6.2: L. johnsonii N6.2 10\^10 CFU in capsule form administered for 8 weeks
21
Placebo
Encapsulated starch placebo administered for 8 weeks Placebo: Encapsulated starch placebo administered for 8 weeks
21
Total42

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyWithdrawal by Subject01

Baseline characteristics

CharacteristicPlaceboProbioticTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
21 Participants21 Participants42 Participants
Age, Continuous21 years23 years21 years
Region of Enrollment
United States
21 Participants21 Participants42 Participants
Sex: Female, Male
Female
14 Participants16 Participants30 Participants
Sex: Female, Male
Male
7 Participants5 Participants12 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
1 / 212 / 20
serious
Total, serious adverse events
0 / 210 / 20

Outcome results

Primary

Number of Participants Reporting Adverse Events

The number of participants reporting Adverse Events was reported.

Time frame: 13 weeks

Population: Subjects completing the probiotic and the placebo intervention.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
ProbioticNumber of Participants Reporting Adverse Events1 Participants
PlaceboNumber of Participants Reporting Adverse Events2 Participants
Secondary

Composite Measure of Blood Chemistry Profiles

Number of clinically relevant out of range values of the comprehensive metabolic panel and hemogram during intervention through washout period vs baseline.

Time frame: 13 weeks

Population: Subjects completing intervention and final blood draw after 4 week washout period.

ArmMeasureValue (NUMBER)
ProbioticComposite Measure of Blood Chemistry Profiles0 events
PlaceboComposite Measure of Blood Chemistry Profiles0 events

Source: ClinicalTrials.gov · Data processed: Feb 26, 2026