Probiotics for COVID19 (disease)

Phase-Based Progress Estimates
COVID19 (disease)+7 More
All Sexes
What conditions do you have?

Study Summary

The elderly, who are often in poorer health, have been particularly affected by the COVID-19 pandemic. Recent study results show that while vaccines have been very effective in the short term, protection for the elderly may not be sufficient 6 months after the 2nd dose. Some countries have started to offer a 3rd dose. We are considering acting on the intestinal flora of the elderly (which is often unbalanced) in order to increase the effectiveness of the vaccination. Indeed, it has been demonstrated that probiotics (which can rebalance the intestinal flora) significantly increase the production of antibodies after vaccination against the flu virus. Our hypothesis is that taking probiotics one month before and one month after the 4th dose of COVID vaccine would result in longer lasting vaccine protection in seniors. This study will include 668 seniors, aged 65-89 years, who have not had COVID-19, who have received 3 doses of an mRNA vaccine and who will accept a 4th dose of vaccine. All participants will take 1 capsule/day (probiotics or placebo) for 1 month and in the middle of this period will receive a 4th dose of vaccine. On five occasions (inclusion, vaccination,1 month, 3 months and 6 months post-vaccination), they will prick their fingertip and express the drop of blood on a blotting paper. They will mail this dried blood sample in an envelope for antibody testing in Quebec City. A subgroup of 100 participants willing to travel the Sherbrooke Clinical Research Center for 2 times (inclusion visit and final visit) will be invited to do a blood test. The investigators expect to reduce by 1/3 the number of seniors who are poorly protected by the 4rd dose of vaccine 6 months after the injection thanks to the probiotics. If successful, this approach could quickly be implemented worldwide as probiotics have few side effects and are affordable.

Eligible Conditions
  • COVID19 (disease)
  • Vaccine Reaction
  • COVID-19
  • Elderly

Treatment Effectiveness

Study Objectives

1 Primary · 0 Secondary · Reporting Duration: 6 months

6 months
Decreasing of 33% the percentage of elders without Receptor-Binding Domain (RBD) antibodies, 6 months after the vaccine booster shot

Trial Safety

Trial Design

2 Treatment Groups

1 of 2
1 of 2
Experimental Treatment
Non-Treatment Group

668 Total Participants · 2 Treatment Groups

Primary Treatment: Probiotics · Has Placebo Group · N/A

Experimental Group · 1 Intervention: Taking capsule containing probiotics or placebo · Intervention Types: DietarySupplement
PlaceboComparator Group · 1 Intervention: Taking capsule containing probiotics or placebo · Intervention Types: DietarySupplement

Trial Logistics

Trial Timeline

Approximate Timeline
Screening: ~3 weeks
Treatment: Varies
Reporting: 6 months

Who is running the clinical trial?

Université de SherbrookeLead Sponsor
259 Previous Clinical Trials
66,874 Total Patients Enrolled
CHU de Quebec-Universite LavalOTHER
152 Previous Clinical Trials
100,799 Total Patients Enrolled
Jean-Charles Pasquier, DrStudy DirectorUniversité de Sherbrooke
1 Previous Clinical Trials
17 Total Patients Enrolled

Eligibility Criteria

Age 65+ · All Participants · 1 Total Inclusion Criteria

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About The Reviewer

Michael Gill preview

Michael Gill - B. Sc.

First Published: October 10th, 2021

Last Reviewed: October 21st, 2022

Michael Gill holds a Bachelors of Science in Integrated Science and Mathematics from McMaster University. During his degree he devoted considerable time modeling the pharmacodynamics of promising drug candidates. Since then, he has leveraged this knowledge of the investigational new drug ecosystem to help his father navigate clinical trials for multiple myeloma, an experience which prompted him to co-found Power Life Sciences: a company that helps patients access randomized controlled trials.