Effects of a Placebo Probiotic on Gut Health and General Well-being in Individuals With Mild Gastrointestinal Symptoms (PlaCIBO)

A 3-week Randomized Controlled Trial on the Efficacy of a Placebo Probiotic in Rebalancing Gut Health and Fostering Physical and Emotional Well-being in Individuals With Mild Gastrointestinal Symptoms

The present study is aimed at exploring whether positive expectations of receiving a three-week treatment with a probiotic supplement (in fact a placebo) improve symptoms of gastrointestinal distress and promote physical and emotional well-being in healthy individuals with mild gastrointestinal symptoms. At first, a comparison is planned between (1) a classic deceptive placebo manipulation (Deceptive Placebo group, DP), and (2) a control condition (Control group, C), in which no placebo substance will be administered. After the three-week waiting list, the Control group will be invited to take the placebo probiotic pills in an "open-label" fashion (Open Label Placebo, OLP). Specifically, participants will be informed that the pills are inert placebos. An exploratory analysis will help to clarify whether the OLP paradigm leads to significant effects, based on a within-group (C- OLP) and between-group comparison (DP-OLP).

Study Overview

• Status: Recruiting
• Conditions: Healthy
• Intervention / Treatment: Other: Placebo probiotic; Other: Open-Label Placebo probiotic; Other: Control-no treatment

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Diletta Barbiani; Phone Number: +393338059338; Email: diletta.barbiani@unicatt.it

Study Locations

• Italy
  • Milan, Italy, 20123
    • Recruiting
    • Catholic University of the Sacred Heart
    • Contact: Diletta Barbiani; Phone Number: +393338059338; Email: diletta.barbiani@unicatt.it

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Age between 20 and 65
• Individuals with mild gastrointestinal symptoms (e.g., digestive issues, acid reflux, constipation) such that normal every-day activities are not severly compromised.

Exclusion Criteria:

• Individuals with a diagnosis of functional gastrointestinal disorders (e.g., irritable bowel syndrome, ulcerative colitis, chronic inflammatory bowel diseases).
• Individuals suffering from neurodegenerative diseases and/or psychiatric conditions
• Individuals taking probiotic supplementation at the time of enrollment in the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Deceptive Placebo	Other: Placebo probiotic; Three-week consumption of placebo probiotic capsules passed off as being actual probiotics
Other: Control - Open-Label PLacebo; The Control Arm will not be exposed to any intervention for the first three weeks. After this time and for the following three weeks, participants will receive placebo probiotic pills in an open-label fashion: they will be honestly informed that the pills are inert placebos.	Other: Open-Label Placebo probiotic; Participants of the Control group will be switched to this condition after three weeks and receive placebo probiotic capsules for the following three-weeks of no intervention. Specifically, they will be honestly informed that the capsules are inert placebos.; Other: Control-no treatment; For the first three weeks, the Control group will not be exposed to any intervention.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Change from Baseline in the Gastrointestinal Symptom Rating Scale (GSRS) total score at 3 weeks.	Baseline and 3 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from Baseline in the Digestion-Associated Quality Of Life Questionnaire (DQLQ) total score at 3 weeks.		Baseline and 3 weeks
Change from Baseline in Stool Form as assessed by means of the Bristol Stool Scale	The Bristol stool scale is a diagnostic medical tool designed to classify the form of human stool into seven categories.	Day 2/3 and day 19/20 from Baseline
Change from Baseline in Fatigue Levels as assessed by means of the Multidimensional Fatigue Inventory (MFI-20) at 3 weeks.	Items are scored 1-5, with 10 [fatigue-]positively phrased items reverse scored (items 2, 5, 9, 10, 13, 14, 16, 17, 18, 19). In the final score, high scores represent more fatigue.	Baseline and 3 weeks
Change from Baseline in Sleepiness Levels as assessed by means of the The Epworth sleepiness scale at 3 weeks.	Final total score ranges from 0 to 24. Scores from 0 to 10 show average (normal) daytime sleepiness. A result from 11 to 24 indicates excessive (abnormal) daytime sleepiness.	Baseline and 3 weeks
Change from Baseline in Positive and Negative affect as assessed by means of the Positive and Negative Affect Schedule (PANAS) at 3 weeks.		Baseline and 3 weeks
Change from Baseline in Stress Levels as assessed by means of the Perceived Stress Scale (PSS) 3 weeks.	The scale comprises of 10 items, with scores ranging from 0 ( = Never) to 4 ( = Very Often). Scores ranging from 0-13 would be considered low stress. Scores ranging from 14-26 would be considered moderate stress. Scores ranging from 27-40 would be considered high perceived stress.	Baseline and 3 weeks

Collaborators and Investigators

• Sponsor: Catholic University of the Sacred Heart

Study record dates

Study Major Dates

• Study Start (Actual): November 20, 2024
• Primary Completion (Estimated): April 1, 2025
• Study Completion (Estimated): April 1, 2025

Study Registration Dates

• First Submitted: November 27, 2024
• First Submitted That Met QC Criteria: December 2, 2024
• First Posted (Estimated): December 6, 2024

Study Record Updates

• Last Update Posted (Estimated): December 6, 2024
• Last Update Submitted That Met QC Criteria: December 2, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: Placebo Effect; Gastrointestinal Symptoms; Open-Label Placebo
• Other Study ID Numbers: PlaCIBO_MtBlab

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No