A Phase 3 interventional study of Probio-Tec BG-VCap-6.5 and Placebo in Mania (Neurotic), sponsored by University of Texas Southwestern Medical Center. Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2025-12-19.
Sponsored by University of Texas Southwestern Medical Center · Phase 3, Interventional, and Treatment
This will be a 24-week, randomized, double-blind, placebo-controlled trial of adjunctive probiotic therapy in 66 persons hospitalized with a manic or mixed episode. The active study compound will consist of capsules containing approximately 10\^9 colony forming units of the probiotic organisms, Lactobacillus GG and Bifidobacteria lactis strain Bb12. The dose has been selected because it has been used safely in other probiotic trials, was well-tolerated by the participants in two previous trials of individuals with schizophrenia or mania, and was utilized in the original trial on which this replication is based. This dose is higher than that available in most commercially-sold health food supplements. Following hospital discharge, participants will be randomized to receive adjunctive probiotic or placebo for a 24 week period. It is anticipated that of the 66 participants randomized, \~50 (75%) will complete the full 24 weeks of the study. The primary outcome is relapse, defined as re-hospitalization (e.g., admission to an inpatient unit) for psychiatric symptoms following a previous hospital discharge by at least 2 weeks. The occurrence of new mood episodes, the severity of psychiatric symptoms, and any changes in cognitive test scores over the course of the study will also be evaluated. Changes in the levels of inflammatory markers as well as changes in gut microbiota will be evaluated at three time intervals over the course of the study.
Primary Aim 1. To determine if adjunctive probiotic administration can reduce relapse for participants first hospitalized for mania. Hypothesis: Participants receiving adjunctive probiotic microorganisms vs. adjunctive placebo will have a lower rate of relapse as defined by a re-hospitalization (e.g., admission to an inpatient unit) during the 24 week study period.
Secondary Outcomes. The number of new mood episodes, the severity of psychiatric symptoms, and changes in cognitive scores over the 24 week study period will be evaluated.
Exploratory Aim 1. To study the effect of probiotic therapy in lowering the levels of inflammatory markers following an acute episode of mania. Hypothesis: Participants receiving adjunctive probiotic microorganisms vs. adjunctive placebo will have reduced levels of antibodies to casein, gliadin, and the NMDA receptor, and reduced levels of C-Reactive protein and the cytokine TNF alpha following 24 weeks of probiotic therapy.
Exploratory Aim 2. To evaluate changes in the gut microbiota following probiotic administration. Hypothesis: Probiotic administration will enrich the gut microbiota of participants with the given microorganisms and these changes may correlate to changes in the peripheral inflammatory markers being measured.
166 studies on the registry are indexed under Mania; 13 are open to participants now.
This study's enrollment of 67 is below the median of 89 across 138 interventional studies indexed under Mania.
Browse Mania studies →University of Texas Southwestern Medical Center is the lead sponsor of 1,010 studies on the registry; 199 are open to participants now.
Of its 139 completed or terminated interventional studies of FDA-regulated products, 105 (76%) have results posted.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
DSM diagnostic criteria
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive capsules containing placebo for 24-weeks.
Other: Placebo
Participants will receive capsules containing approximately 10\^9 colony forming units of the probiotic organisms, Lactobacillus GG and Bifidobacteria lactis strain Bb12 for 24-weeks.
Combination Product: Probio-Tec BG-VCap-6.5
The product under investigation is a probiotic containing two microorganisms (Lactobacillus rhamnosus, LGG® and Bifidobacterium animalis subsp. lactis, BB-12®, referred to as LGG® and BB-12®, respectively) and is offered commercially as "Probio-Tec BG-VCap-6.5". This composition is formulated to contain a minimum of 1 billion (1.0 x 10\^9) CFU (Colony Forming Units) per dose (capsule), including equal numbers of the two strains; i.e. 0.5 x 10\^9 CFU of each of LGG® and BB-12® at the time of manufacture. The product will be administered orally.
This placebo is made almost identically to the Probio-Tec but without active microorganisms.
Rate of Relapse
'Relapse' is defined as re-hospitalization (e.g., admission to an inpatient unit) for psychiatric symptoms following a previous hospital discharge by at least 2 weeks. The rate of relapse was calculated by dividing the number of re-hospitalizations per group (i.e., Placebo, Probiotic) by the number of participants per group so the unit is re-hospitalizations/participant.
Time frame: 24 weeks
| Milestone | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 |
|---|---|---|
| Started | 36 | 31 |
| Completed | 20 | 25 |
| Not completed | 16 | 6 |
'Relapse' is defined as re-hospitalization (e.g., admission to an inpatient unit) for psychiatric symptoms following a previous hospital discharge by at least 2 weeks. The rate of relapse was calculated by dividing the number of re-hospitalizations per group (i.e., Placebo, Probiotic) by the number of participants per group so the unit is re-hospitalizations/participant.
| Proportion of Participants | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 |
|---|---|---|
| Rate of Relapse | .11 | .13 |
Collected over 24 weeks. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Placebo | 1/36 (2.8%) | 3/36 (8.3%) | 20/36 (55.6%) |
| Probiotic-Probio-Tec BG-VCap-6.5 | 0/31 (0%) | 1/31 (3.2%) | 20/31 (64.5%) |
| Event | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 |
|---|---|---|
| Hospitalization due to Manic SymptomsPsychiatric disorders | 1/36 | 1/31 |
| Death due to Surgical ComplicationSurgical and medical procedures | 1/36 | 0/31 |
| Suicide AttemptPsychiatric disorders | 1/36 | 0/31 |
| Event | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 |
|---|---|---|
| DiarrheaGastrointestinal disorders | 10/36 | 7/31 |
| BloatingGastrointestinal disorders | 5/36 | 1/31 |
| Increased AppetiteGastrointestinal disorders | 1/36 | 3/31 |
| Increased Frequency of Bowel MovementsGastrointestinal disorders | 0/36 | 3/31 |
| NauseaGastrointestinal disorders | 1/36 | 3/31 |
| Weight GainMetabolism and nutrition disorders | 0/36 | 3/31 |
| Common ColdInfections and infestations | 3/36 | 2/31 |
| FlatulenceGastrointestinal disorders | 3/36 | 1/31 |
| Stomach DiscomfortGastrointestinal disorders | 2/36 | 2/31 |
| HeadacheNervous system disorders | 0/36 | 2/31 |
| Age, Categorical(Participants) | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 | Total |
|---|---|---|---|
| <=18 years | 1 | 1 | 2 |
| Between 18 and 65 years | 35 | 30 | 65 |
| >=65 years | 0 | 0 | 0 |
| Age, Continuous(Years) | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 | Total |
|---|---|---|---|
| Mean | 33.97 ± 17.08 | 32.29 ± 10.18 | 33.19 ± 12.27 |
| Sex: Female, Male(Participants) | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 | Total |
|---|---|---|---|
| Female | 17 | 18 | 35 |
| Male | 19 | 13 | 32 |
| Race (NIH/OMB)(Participants) | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 2 | 1 | 3 |
| Native Hawaiian or Other Pacific Islander | 1 | 1 | 2 |
| Black or African American | 8 | 12 | 20 |
| White | 25 | 17 | 42 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 0 | 0 | 0 |
| Ethnicity (NIH/OMB)(Participants) | Placebo | Probiotic-Probio-Tec BG-VCap-6.5 | Total |
|---|---|---|---|
| Hispanic or Latino | 14 | 5 | 19 |
| Not Hispanic or Latino | 22 | 26 | 48 |
| Unknown or Not Reported | 0 | 0 | 0 |
PDFs hosted by the registry, ClinicalTrials.gov.
Ran from Sep 2018 to primary completion in Sep 2024, 72 months.
Results were first posted in Dec 2025, 1 year 2 months after primary completion.
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