A Phase 2/3 interventional study of Fecal Microbiota Transplantation in Major Depressive Disorder and Irritable Bowel Syndrome, sponsored by Valerie Taylor. Active, not recruiting at 1 site in Canada. Open to participants aged 18 Years to 60 Years. Per ClinicalTrials.gov, last updated 2026-03-19.
Sponsored by Valerie Taylor · Phase 2/3, Interventional, and Other
This study is a phase 2/3 open-label controlled trial (CT) in which adults with Major Depressive Disorder (MDD) and adults who have MDD plus comorbid Inflammatory Bowel Syndrome (IBS) will be assigned to either receive oral Fecal Microbiota Transplantation (FMT) or to continue with the treatment they are currently receiving in a Treatment As Usual (TAU) arm. An IBS alone group receiving TAU will be recruited as a clinical control group.
The primary goals of this study are to determine effectiveness, safety and tolerability of oral FMT in adults with MDD and in MDD who have comorbid IBS. Additional goals are to characterize patterns and progressions of cognitive and neural correlates associated with MDD and with MDD + IBS and to determine if they improve with FMT. It is known that both, individuals with MDD and those with MDD and IBS show cognitive alterations as well as changes in neural structures, but this study is designed to see if those are changed with treatment response to FMT. Additionally, trial feasibility will be monitored via recruitment rate, study visits adherence and participant retention to inform future trial scalability."
2,741 studies on the registry are indexed under Depressive Disorder, Major; 558 are open to participants now.
This study's enrollment of 133 is above the median of 80 across 2,282 interventional studies indexed under Depressive Disorder, Major.
Browse Depressive Disorder, Major studies →Valerie Taylor is the lead sponsor of 3 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Between 18-60 years of age:
Participants should be at least 18 years old and not older than 60 years at the day of screening
Exclusion Criteria:
Participant meets Diagnostic and Statistical Manual of Mental Disorders (DSM-5)[1] Criteria for the following conditions according to the M.I.N.I:
Eligible and consenting patients will be assigned 1:1 to receive either FMT from a healthy donor or continuing on their usual medication for MDD, i.e., treatment as usual (TAU). This arm will continue to receive their usual anti-depressant.
Eligible and consenting patients will be assigned 1:1 to receive either FMT from a healthy donor or continuing on their usual medication for MDD, i.e., treatment as usual (TAU). This arm will be assigned to receive FMT provided by healthy donors.
Biological: Fecal Microbiota Transplantation
Biological: Fecal Microbiota Transplantation
Data from healthy comparison (HC) participants will be drawn from another completed research study. Healthy comparison participants who will best match the patient population enrolled in the current trial and who consented to data sharing will be selected.
FMT is a technique in which intestinal microbiota are transferred from a healthy screened donor to a patient, with the goal being to introduce or restore a stable microbial community in the gut.
Also known as: FMT
The Montgomery-Åsberg Depression Rating Scale (MADRS)
a 10-item questionnaire which psychiatrists use to measure the severity of depressive episodes in patients with mood disorders. This will be used to evaluate the effectiveness of adjunct oral FMT as compared to TAU with currently accepted approved therapy for MDD. The MADRS overall score ranges from 0 to 60. Each item yields a score of 0 to 6 and Higher MADRS score indicates more severe depression
Time frame: Baseline to week 13
IBS Symptom Severity Scale (IBS-SSS)
The IBS-SSS is a 5-item questionnaire that is used to assess the severity and frequency of abdominal pain, severity of abdominal distention, dissatisfaction with bowel habits, and interference with quality of life over the past 10 days. Scores on the IBS-SSS can range from 0 to 500 with higher scores indicating more severe symptoms. Subjects can be categorized as having mild (75-175), moderate (175-300), or severe (\>300) IBS.
Time frame: Baseline to week 13
Toronto Side Effect Scale (TSES)
The TSES is a 32-item instrument that is designed to establish incidence, frequency, and severity of CNS, GI, and sexual side effects. For each side effect, frequency and severity are measured on a 5-point scale. intensity is measured by multiplying frequency and severity.
Time frame: Baseline to Week 13
IBS specific Quality of Life (IBS-QoL)
is a self-report 34-item instrument used to assess the impact of IBS and its treatment. used to examine GI tolerability in patients with IBS. The individual responses to the 34 items are summed and averaged for a total score and then transformed to a 0-100 scale for ease of interpretation with higher scores indicating better IBS specific quality of life.
Time frame: Baseline to Week 13
nuclear magnetic resonance (NMR) spectrometry
To assess the effect of FMT on microbiome profile (community structure and functional metagenome).
Time frame: Baseline to Week 13
structural and functional neuroimaging
fMRI to examine brain imaging changes in response to FMT
Time frame: Baseline to week 13
Number of participants recruited, and completed the study visits
trial feasibility will be monitored via recruitment rate, study visits adherence and participant retention to inform future trial scalability
Time frame: From Baseline to week 13
Plan to share: No
This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Valerie Taylor