Type 1 Diabetes (T1D)Phase 2NCT03961347
Lactobacillus Johnsonii Supplementation in Adults With T1D
A Phase 2 study testing L. johnsonii Probiotic in people with Type 1 Diabetes (T1D), run by University of Florida at 1 site in United States.
Trial summary
While genetics demonstrated a major risk factor for the development of type 1 diabetes (T1D), microbiota dysbiosis has been suggested as an elicitor in immunological tolerance and of beta cell autoimmunity. Read more about this study
- Who is it for?
- Ages 18 to 45 years
- Conditions the study is for
- Type 1 Diabetes (T1D)
- What is being tested?
- L. johnsonii Probiotic
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 46 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Feb 2020to 18 Mar 2026
- Phase
- Phase 2
- Are there results?
- None posted in the registry
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 45 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Have confirmed T1D by physician diagnosis
- Have normal values at screening for CBC and complete metabolic profiles (with the exception of fasting glucose and HbA1c).
- Are able to swallow a capsule.
- Are willing to complete weekly online questionnaires.*
- Are willing to consume a probiotic or placebo capsule daily for 24 weeks.
- Are willing to provide stool samples throughout the study.
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- Are willing to provide blood samples throughout the study.
- Are willing to take three 2-hour Mixed-Meal Tolerance Tests (MMTTs).
- Are able to access a computer with Internet throughout the study.*
- Note: Going into the study, we want the participants to have daily internet access. However, if this changes once they are in the study, we will provide paper copies of the questionnaires.
Who cannot join
- Have had or are currently being treated for any diseases or illnesses such as gastrointestinal disease (gastric ulcers, Crohn's, ulcerative colitis, etc.).
- Have chronic disease kidney disease.
- Have had or are currently being treated for other immune-compromising diseases or conditions (HIV, AIDS, hepatitis, cancer, leukemia, transplant patient, Lupus, DiGeorge syndrome, selective deficiency of Immunoglobulin A (IgA), Bruton's disease etc.).
- Have an underlying structural heart disease.
- Currently live with an immunocompromised person.
- Are currently taking medications for constipation and/or diarrhea.
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- Have taken antibiotics within the past 2 weeks prior to randomization.
- Are currently taking a probiotic supplement and are unwilling to discontinue it a minimum of 2 weeks prior to the study start.
- Are a current smoker.
- Are currently pregnant or lactating or a female who plans to become pregnant in the next 6 months.
- Have a known allergy to milk or milk protein.
Trial locations and contacts
1 site in 1 country.
United States1 site
UF Clinical Research Center
Gainesville, Florida, 32610
About this study
Official title: Evaluation of Safety, Tolerability and Immunological Responses to Lactobacillus Johnsonii N6.2 Supplementation in Adults With Diabetes Type 1
While genetics demonstrated a major risk factor for the development of type 1 diabetes (T1D), microbiota dysbiosis has been suggested as an elicitor in immunological tolerance and of beta cell autoimmunity. The probiotic Lactobacillus johnsonii N6.2 may prevent or restore the gut flora and show systemic impacts and adaptive immunity in the T1D population thereby preserving beta cell function.
- Conditions
- Type 1 Diabetes (T1D)
- Being tested
- L. johnsonii Probiotic, Placebo Capsule
- Keywords
- probiotics, genetics
- Medical subject headings
- Diabetes Mellitus, Type 1
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
L. johnsonii ProbioticDrug
Participants will consume one capsule of L. johnsonii probiotic daily for 24 weeks.
Placebo CapsuleDrug
Participants will consume one capsule of placebo capsule of dried skim milk daily for 24 weeks.
| Study group | Role | What they receive |
|---|---|---|
| Probiotic Group | Active comparator | The probiotic group will receive a daily capsule with Lactobacillus johnsonii N6.2 1x109 Colony Forming Units (CFUs). Participants will consume one capsule (treatment or placebo) daily for 24 weeks. Receives: Drug: L. johnsonii Probiotic |
| Placebo Group | Placebo comparator | The placebo group will receive a capsule daily with dried skim milk (vehicle of the probiotic). Participants will consume one capsule (treatment or placebo) daily for 24 weeks. Receives: Drug: Placebo Capsule |
What is being measured
The primary outcome is the main question the study is designed to answer.
Safety will be evaluated according to complete blood count (CBC) and complete comprehensive metabolic panel (CMP)
CBC and CMP will be evaluated at four different time points during study: 1st measure will be at screening visit and before starting intervention (visit 1/week -4, baseline period), 2nd measure will be after 12 weeks after starting intervention (visit 2/ week 12), 3rd measure will be after the 24 weeks of intervention (visit 3/ week 24) and the 4th measure will be 24 weeks later, end of washout period (visit 4/week 48). Values should be within the normal range except for glucose.
Measured: 52 weeks
Tolerance will be evaluated according to their responses on weekly questionnaires
The weekly questionnaire will ask participants to respond to questions regarding their gastrointestinal health (bowel movement frequency, gastrointestinal and other symptoms (i.e., constipation, diarrhea, stomach pain) and general wellness (if you consumed an antibiotic, visited a doctor, etc.). The questionnaires follow a scale from 1-7, 1 = No discomfort at all, 7 = Very severe discomfort.
Measured: 52 weeks
Adverse Event and/or Serious Adverse Event
Adverse Event and/or Serious Adverse Event will be recorded daily by parents and notified to investigator within 24 hrs., in particular gastro-intestinal symptoms, fever and rashes.
Measured: 24 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 May 2019
- Study start1 Feb 2020
- Primary completion18 Mar 2026
- Study completion18 Mar 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Type 1 Diabetes (T1D)Studies of the same condition, open and under way.
- More trials run by University of FloridaThe 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 2
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- A randomized, double-blinded, placebo-controlled clinical trial will be carried out in subjects between 18-45 years old with T1D.
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 46 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Florida
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Michael Haller, Principal investigator, University of Florida
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03961347
- Sponsor's protocol ID
- IRB201901428 -N
- Other IDs
- OCR22502, 1R01DK121130-01A1
- Status last verified
- Apr 2026
- First submitted
- 22 May 2019
- Last updated
- 18 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of Safety, Tolerability and Immunological Responses to Lactobacillus Johnsonii N6.2 Supplementation in Adults With Diabetes Type 1
- ClinicalTrials.gov ID
- NCT03961347
- Acronym / sponsor ID
- IRB201901428 -N
- Conditions
- Type 1 Diabetes (T1D)
- Keywords
- probiotics, genetics
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 46 participants (actual)
- Lead sponsor
- University of FloridaUniversity, hospital or other
- Collaborators
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
- Study start
- 1 Feb 2020 (actual)
- Primary completion
- 18 Mar 2026 (actual)
- Study completion
- 18 Mar 2026 (actual)
- First posted
- 23 May 2019 (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.
While genetics demonstrated a major risk factor for the development of type 1 diabetes (T1D), microbiota dysbiosis has been suggested as an elicitor in immunological tolerance and of beta cell autoimmunity. The probiotic Lactobacillus johnsonii N6.2 may prevent or restore the gut flora and show systemic impacts and adaptive immunity in the T1D population thereby preserving beta cell function.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- A randomized, double-blinded, placebo-controlled clinical trial will be carried out in subjects between 18-45 years old with T1D.
| Arm | Type | Receives |
|---|---|---|
| Probiotic Group | Active comparator | Drug: L. johnsonii ProbioticThe probiotic group will receive a daily capsule with Lactobacillus johnsonii N6.2 1x109 Colony Forming Units (CFUs). Participants will consume one capsule (treatment or placebo) daily for 24 weeks. |
| Placebo Group | Placebo comparator | Drug: Placebo CapsuleThe placebo group will receive a capsule daily with dried skim milk (vehicle of the probiotic). Participants will consume one capsule (treatment or placebo) daily for 24 weeks. |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (10 listed)
- Have confirmed T1D by physician diagnosis
- Have normal values at screening for CBC and complete metabolic profiles (with the exception of fasting glucose and HbA1c).
- Are able to swallow a capsule.
- Are willing to complete weekly online questionnaires.*
- Are willing to consume a probiotic or placebo capsule daily for 24 weeks.
Key exclusion criteria (11 listed)
- Have had or are currently being treated for any diseases or illnesses such as gastrointestinal disease (gastric ulcers, Crohn's, ulcerative colitis, etc.).
- Have chronic disease kidney disease.
- Have had or are currently being treated for other immune-compromising diseases or conditions (HIV, AIDS, hepatitis, cancer, leukemia, transplant patient, Lupus, DiGeorge syndrome, selective deficiency of Immunoglobulin A (IgA), Bruton's disease etc.).
- Have an underlying structural heart disease.
- Currently live with an immunocompromised person.
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 |
|---|---|---|
| L. johnsonii ProbioticParticipants will consume one capsule of L. johnsonii probiotic daily for 24 weeks. | Drug | Probiotic Group |
| Placebo CapsuleParticipants will consume one capsule of placebo capsule of dried skim milk daily for 24 weeks. | Drug | Placebo Group |
Primary outcome
Safety will be evaluated according to complete blood count (CBC) and complete comprehensive metabolic panel (CMP)
Time frame: 52 weeks
CBC and CMP will be evaluated at four different time points during study: 1st measure will be at screening visit and before starting intervention (visit 1/week -4, baseline period), 2nd measure will be after 12 weeks after starting intervention (visit 2/ week 12), 3rd measure will be after the 24 weeks of intervention (visit 3/ week 24) and the 4th measure will be 24 weeks later, end of washout period (visit 4/week 48). Values should be within the normal range except for glucose.
Tolerance will be evaluated according to their responses on weekly questionnaires
Time frame: 52 weeks
The weekly questionnaire will ask participants to respond to questions regarding their gastrointestinal health (bowel movement frequency, gastrointestinal and other symptoms (i.e., constipation, diarrhea, stomach pain) and general wellness (if you consumed an antibiotic, visited a doctor, etc.). The questionnaires follow a scale from 1-7, 1 = No discomfort at all, 7 = Very severe discomfort.
Adverse Event and/or Serious Adverse Event
Time frame: 24 weeks
Adverse Event and/or Serious Adverse Event will be recorded daily by parents and notified to investigator within 24 hrs., in particular gastro-intestinal symptoms, fever and rashes.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 May 2026.
- Individual participant dataSharing planned: No
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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. This study is not recruiting at the moment.
Michael Haller principal investigator
University of Florida
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing L. johnsonii Probiotic in people with Type 1 Diabetes (T1D), run by University of Florida 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 10 inclusion and 11 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: finished, as of the sponsor's last update on 18 May 2026. 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Safety will be evaluated according to complete blood count (CBC) and complete comprehensive metabolic panel (CMP) (time frame: 52 weeks). The study lists 3 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 18 May 2026.