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Gut Feeling: Understanding the Mechanisms Underlying the Antidepressant Properties of Probiotics (PROMEX)

Primary Purpose

Major Depressive Disorder

Status
Completed
Phase
Not Applicable
Locations
United Kingdom
Study Type
Interventional
Intervention
Multi-strain probiotic
Placebo
Sponsored by
King's College London
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional basic science trial for Major Depressive Disorder focused on measuring probiotic, depression, microbiome, bacteria

Eligibility Criteria

18 Years - 55 Years (Adult)All SexesAccepts Healthy Volunteers

Inclusion criteria for MDD participants:

  • aged 18-55;
  • currently in a depressive episode according to DSM-5 criteria, who are currently on antidepressant treatment but remain symptomatic (HAM-D17 score >13);
  • on stable treatment regimen of an approved treatment for at least 6 weeks;
  • non-smokers;
  • for participants willing to take part in the neuroimaging component: right-handed, no contraindications, non-claustrophobic, weight <126kg;

Exclusion criteria for MDD participants:

  • eating disorder, bipolar disorder, schizophrenia or psychotic symptoms;
  • substance dependence in the past year, except for caffeine;
  • active suicidal ideation;
  • use of probiotic supplements in the past 2 weeks, or regular use of a probiotic;
  • use of antibiotics in the past 12 weeks;
  • history of allergic reaction to any of the components of BioKult;
  • history of history of a systemic medical illness;
  • current presence of significant GI problems or disease or history of major GI surgery;
  • pregnancy or breastfeeding;
  • following a dietary regimen unrepresentative of the general population (e.g. fasting or following a specific diet);
  • regular/current use of antacids, proton pump inhibitors, laxatives, antidiarrheals;

Inclusion criteria for Healthy Volunteers:

  • Aged 18-55;
  • No current or historic presence of depression, other psychiatric disorder or substance dependence
  • No history of a systemic medical illness;
  • No family history of psychiatric disorder;
  • Non-smoker;
  • Not used probiotic supplements in the past 2 weeks, nor regular use of a probiotic;
  • Not used antibiotics in the past 12 weeks;
  • No current presence of gastrointestinal disease, or history of major GI surgery;
  • No reported regular/current use of antacids, proton pump inhibitors, laxatives, antidiarrheals;
  • pregnancy or breastfeeding;
  • not currently following a dietary regimen or dietary restrictions unrepresentative of the general population (e.g. fasting or following a specific diet);

Sites / Locations

  • King's College London

Arms of the Study

Arm 1

Arm 2

Arm Type

Experimental

Placebo Comparator

Arm Label

Multi-strain probiotic "BioKult"

Placebo

Arm Description

4 capsules daily for 8 weeks

4 capsules daily for 8 weeks

Outcomes

Primary Outcome Measures

gut microbiota in MDD
species diversity and abundance at the level of organisational taxonomic units (OTUs) will be measured with 16S ribosomal RNA (rRNA) sequencing
differences in gut microbiota between MDD and healthy volunteers
species diversity and abundance at the level of OTUs will be measured with 16SrRNA-based sequencing and compared between the two groups
gut microbiota changes in MDD following probiotic intervention and their correlation to change in depressive symptoms
species diversity and abundance at the level of OTUs will be measured with 16SrRNA-based sequencing and depressive symptoms will be measured with the Inventory of Depressive Symptomatology Self-Report (IDS-SR) and the Hamilton Depression Rating Scale (HAM-D17)

Secondary Outcome Measures

Neurotransmitters
levels of glutamate and gamma-aminobutyric acid (GABA) will be measured with Magnetic Resonance Imaging (MRS)
Blood
levels of tumor necrosis factor (TNF-a), interleukins IL-1β, IL-6, IL-17, and C-reactive protein (CRP) will be measured
Brain activity
measured with functional magnetic resonance imaging (fMRI)

Full Information

First Posted
March 22, 2019
Last Updated
June 29, 2022
Sponsor
King's College London
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1. Study Identification

Unique Protocol Identification Number
NCT03893162
Brief Title
Gut Feeling: Understanding the Mechanisms Underlying the Antidepressant Properties of Probiotics
Acronym
PROMEX
Official Title
Gut Feeling: Understanding the Mechanisms Underlying the Antidepressant Properties of Probiotics
Study Type
Interventional

2. Study Status

Record Verification Date
September 2021
Overall Recruitment Status
Completed
Study Start Date
July 1, 2019 (Actual)
Primary Completion Date
June 29, 2022 (Actual)
Study Completion Date
June 30, 2022 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
King's College London

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
No

5. Study Description

Brief Summary
Previous research has suggested that probiotics can improve depressive symptoms in patients with Major Depressive Disorder (MDD), particularly when used in addition to antidepressants. The aim of this exploratory pilot study is to improve the investigator's understanding of the mechanisms underlying these effects. This study will assess the effects of an 8-week double-blind placebo-controlled probiotic intervention on the gut microbiome, inflammatory marker levels, brain activity and neurotransmitter levels in patients with MDD and their relationship to changes in mood. This study will also recruit a group of demographically-matched healthy controls for gut microbiome comparison with the MDD group (non-interventional).

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Major Depressive Disorder
Keywords
probiotic, depression, microbiome, bacteria

7. Study Design

Primary Purpose
Basic Science
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
ParticipantInvestigatorOutcomes Assessor
Allocation
Randomized
Enrollment
50 (Actual)

8. Arms, Groups, and Interventions

Arm Title
Multi-strain probiotic "BioKult"
Arm Type
Experimental
Arm Description
4 capsules daily for 8 weeks
Arm Title
Placebo
Arm Type
Placebo Comparator
Arm Description
4 capsules daily for 8 weeks
Intervention Type
Dietary Supplement
Intervention Name(s)
Multi-strain probiotic
Other Intervention Name(s)
"BioKult"
Intervention Description
The intervention in this study is a multi-strain probiotic which contains: Bacillus subtilis, Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium infantis, Bifidobacterium longum, Lactobacillus acidophilus, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus casei, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus helveticus, Lactobacillus salivarius, Lactococcus lactis ssp. lactis, Streptococcus thermophilus. Each capsule contains minimum 2 billion live microorganisms per capsule, equivalent to 10 billion live microorganisms per gram.
Intervention Type
Other
Intervention Name(s)
Placebo
Intervention Description
Visually identical capsules in identical packaging containing no active bacteria.
Primary Outcome Measure Information:
Title
gut microbiota in MDD
Description
species diversity and abundance at the level of organisational taxonomic units (OTUs) will be measured with 16S ribosomal RNA (rRNA) sequencing
Time Frame
baseline
Title
differences in gut microbiota between MDD and healthy volunteers
Description
species diversity and abundance at the level of OTUs will be measured with 16SrRNA-based sequencing and compared between the two groups
Time Frame
baseline
Title
gut microbiota changes in MDD following probiotic intervention and their correlation to change in depressive symptoms
Description
species diversity and abundance at the level of OTUs will be measured with 16SrRNA-based sequencing and depressive symptoms will be measured with the Inventory of Depressive Symptomatology Self-Report (IDS-SR) and the Hamilton Depression Rating Scale (HAM-D17)
Time Frame
change from baseline to week 8
Secondary Outcome Measure Information:
Title
Neurotransmitters
Description
levels of glutamate and gamma-aminobutyric acid (GABA) will be measured with Magnetic Resonance Imaging (MRS)
Time Frame
change from baseline to week 8
Title
Blood
Description
levels of tumor necrosis factor (TNF-a), interleukins IL-1β, IL-6, IL-17, and C-reactive protein (CRP) will be measured
Time Frame
change from baseline to week 8
Title
Brain activity
Description
measured with functional magnetic resonance imaging (fMRI)
Time Frame
change from baseline to week 8

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
55 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion criteria for MDD participants: aged 18-55; currently in a depressive episode according to DSM-5 criteria, who are currently on antidepressant treatment but remain symptomatic (HAM-D17 score >13); on stable treatment regimen of an approved treatment for at least 6 weeks; non-smokers; for participants willing to take part in the neuroimaging component: right-handed, no contraindications, non-claustrophobic, weight <126kg; Exclusion criteria for MDD participants: eating disorder, bipolar disorder, schizophrenia or psychotic symptoms; substance dependence in the past year, except for caffeine; active suicidal ideation; use of probiotic supplements in the past 2 weeks, or regular use of a probiotic; use of antibiotics in the past 12 weeks; history of allergic reaction to any of the components of BioKult; history of history of a systemic medical illness; current presence of significant GI problems or disease or history of major GI surgery; pregnancy or breastfeeding; following a dietary regimen unrepresentative of the general population (e.g. fasting or following a specific diet); regular/current use of antacids, proton pump inhibitors, laxatives, antidiarrheals; Inclusion criteria for Healthy Volunteers: Aged 18-55; No current or historic presence of depression, other psychiatric disorder or substance dependence No history of a systemic medical illness; No family history of psychiatric disorder; Non-smoker; Not used probiotic supplements in the past 2 weeks, nor regular use of a probiotic; Not used antibiotics in the past 12 weeks; No current presence of gastrointestinal disease, or history of major GI surgery; No reported regular/current use of antacids, proton pump inhibitors, laxatives, antidiarrheals; pregnancy or breastfeeding; not currently following a dietary regimen or dietary restrictions unrepresentative of the general population (e.g. fasting or following a specific diet);
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
James M Stone, MBBS PhD FRCPsych
Organizational Affiliation
Institute of Psychiatry Psychology and Neuroscience, King's College London
Official's Role
Principal Investigator
Facility Information:
Facility Name
King's College London
City
London
ZIP/Postal Code
SE5 8AF
Country
United Kingdom

12. IPD Sharing Statement

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Gut Feeling: Understanding the Mechanisms Underlying the Antidepressant Properties of Probiotics

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