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Clinical Evaluation of the Antidepressant Effect of the Use of Probiotics in Bipolar Disorder

Clinical Evaluation of the Antidepressant Effect of the Use of Probiotics in Bipolar Disorder and Possible Mediating Effects of Systemic and Intestinal Inflammatory Markers in the Microbiota

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05762887
Enrollment
141
Registered
2023-03-10
Start date
2023-01-09
Completion date
2025-03-01
Last updated
2026-05-13

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

Conditions

Bipolar Disorder

Brief summary

Bipolar Disorder (BD) is highly incapacitating and associated with premature mortality. Depressive symptoms and episodes are the most frequent cause of disability in subjects with BD and over half of patients do not respond adequately to approved treatments for this condition, showing the need for new classes of treatments to complement current pharmacotherapy. Previous studies demonstrated that the intestinal flora have potential positive or negative effects on the Central Nervous System and suggest that adding specific strains of bacteria to people's diet may have antidepressant properties.The study proposes to evaluate the clinical benefit of adding probiotics to pharmacological treatments for bipolar depression. This will be a study with 124 subjects (62 receiving probiotics and 62 placebo). The research team in this department has focused especially on non-pharmacological treatments for bipolar disorder (psychotherapy, nutrition and exercise) and is multidisciplinary in scope with psychiatrists, psychologists, nurses, physiotherapists and nutritionists participating in research projects.

Detailed description

It will test, in a proof-of-concept study, the antidepressant efficacy of adjunctive administration of probiotics in bipolar depression and evaluate potential inflammatory and metabolic markers associated with response to treatment. With this objective, 84 individuals with bipolar disorder type I or type II presenting subsyndromal depressive symptoms or a major depressive episode will be recruited. The study design lasts 12 weeks and is expected to last two years.

Interventions

The 124 participants will participate in a randomized, double-blind, placebo-controlled trial in two arms. The probiotic group will consist of 62 patients. These patients will be recruited from the USP Bipolar Disorder Program. This program has an outpatient clinic that offers free medical care to a population of different ethnic groups, with the majority of subjects coming from the middle and lower social classes.

OTHERPlacebo Group

The 124 participants will participate in a randomized, double-blind, placebo-controlled trial in two arms. The placebo group will consist of 62 patients. These patients will be recruited from the USP Bipolar Disorder Program. This program has an outpatient clinic that offers free medical care to a population of different ethnic groups, with the majority of subjects coming from the middle and lower social classes.

Sponsors

University of Sao Paulo
Lead SponsorOTHER
Baszucki Brain Research Fund
CollaboratorOTHER
Milken Institute
CollaboratorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Masking description

All blind clinical assessments will be done by Psychiatrists, members of the University of São Paulo (USP) Bipolar Research Program managed by Michelle Flores. In this study, the intervention will be double-blind: All participants will receive the exact same pill, whether placebo or intervention, with equal packaging-manufacturing.

Intervention model description

A Randomized, Double-Blind, Placebo-controlled

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

* BD type I or type II, according to the use of Mini Internacional Neuropsychiatric Interview (MINI) * Score on the Young Mania Rating Scale (YMRS) \< 8 * Score on the Montgomery-Asberg Depression Rating Scale (MADRS) \> 8 * Be receiving major guideline-approved treatments for bipolar depression for at least 4 weeks

Exclusion criteria

* Pregnant or lactating women * Substance or alcohol dependence * Patients on prolonged antibiotic therapy, immunosuppressive therapies * A recent introduction of antidepressants in the last 15 days * Use of another probiotic, either in the form of food, sachets, capsules and others

Design outcomes

Primary

MeasureTime frameDescription
Outcome12 weeksThe Montgomery-Asberg Depression Rating Scale (MADRS) will be used in order to evaluate the reduction of depressive symptoms. Response to treatment at week-12 will be defined as ≥ 50% reduction in total MADRS total score from baseline. Remission will be defined as MADRS total score ≤ 12.

Countries

Brazil

Contacts

PRINCIPAL_INVESTIGATORBeny lafer, PhD

University of Sao Paulo

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 14, 2026