Modulation of Gut Microbiota to Enhance Health and Immunity
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ClinicalTrials.gov Identifier: NCT04884776 |
Recruitment Status :
Recruiting
First Posted : May 13, 2021
Last Update Posted : August 4, 2021
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Condition or disease | Intervention/treatment | Phase |
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Gut Microbiota COVID-19 Vaccine | Dietary Supplement: Microbiome immunity formula Dietary Supplement: Active placebo | Not Applicable |
HYPOTHESIS We hypothesize that modulating the gut microbiota with a microbiome immunity formula can rebalance the gut microbiota in populations at risk of infection, like, patients with type 2 DM and elderlies and can lower the number of hospitalisation and reduce side effects associated with COVID-19 vaccination.
AIM We aim to evaluate the efficacy of modulating gut microbiota with a microbiome immunity formula in vulnerable subjects (patients with underlying type 2 DM and elderlies) in improving immune functions, reducing adverse events associated with COVID-19 vaccinations and reducing hospitalisation in susceptible individuals during the COVID-19 pandemic.
STUDY DESIGN This is a double-blinded, randomized, active-placebo controlled study comparing a microbiome immunity formula and placebo in enhancing immunity and reducing hospitalisation within one year. Except two kinds of subjects (Substudy 1: Patients with Type 2 DM and Substudy 2: Elderly individual) will be included in respective substudy, all other methodologies are the same. In each substudy, at least half of the recruited subjects will plan to receive COVID-19 vaccination and start to take the study products after vaccination. Recruited subjects will be randomised to receive a microbiome immunity formula or active placebo for 3 months, with another 9 months follow-up after completion of study products.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 484 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Outcomes Assessor) |
Primary Purpose: | Prevention |
Official Title: | Modulation of Gut Microbiota to Enhance Health and Immunity of Vulnerable Individuals During COVID-19 Pandemic |
Actual Study Start Date : | June 1, 2021 |
Estimated Primary Completion Date : | May 31, 2024 |
Estimated Study Completion Date : | May 31, 2024 |

Arm | Intervention/treatment |
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Active Comparator: Active arm
Subject will be instructed to take microbiome immunity formula 2 sachets daily for a total of 12 weeks.
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Dietary Supplement: Microbiome immunity formula
Microbiome immunity formula contains probiotics blend (3 Bifidobacteria, 10 billion CFU per sachet) |
Placebo Comparator: Placebo arm
Subject will be instructed to take active placebo daily for a total of 12 weeks.
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Dietary Supplement: Active placebo
Active placebo contains active vitamin |
- Restoration of gut dysbiosis [ Time Frame: 3 months ]Proportion of patients achieving restoration of gut dysbiosis at 3 months
- Immunogenicity of the COVID-19 vaccine [ Time Frame: 3 months and 6 months ]Measured by serum neutralization assay against pseudo virus and live virus, and IgM and IgG against receptor-binding domain [RBD] and S1
- Change in gut microbiome [ Time Frame: 1, 3, 6, 9 and 12 months ]Measured the microbial analysis result by real time-PCR and metabolite profiling by liquid chromatography-mass spectrometry
- Changes in plasma inflammatory cytokines [ Time Frame: 3 months and 6 months ]Measured the inflammatory cytokines (CRP or ESR) in blood result
- Adverse events [ Time Frame: 12 months ]Adverse events after COVID-19 vaccination
- Number of unscheduled hospitalisation and clinic visits [ Time Frame: 1, 3, 6, 9 and 12 months ]Number of unscheduled hospitalisation and clinic visits
- Changes of quality of life [ Time Frame: 1, 3, 6, 9 and 12 months ]Measured the score of EQ-5D-5L which measure the health-related quality of life
- Changes in glycaemic control [ Time Frame: 3, 6 and 12 months ]Measured by HbA1c

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Substudy 1
Inclusion Criteria:
- Age 18 years - below 65 years
- A confirmed diagnosis of type 2 DM for ≥ 3 months with stable control (i.e. no change in DM medications in recent 2 months)
- Written informed consents obtained
Exclusion Criteria:
- Known history of confirmed COVID-19 infection
- Known active sepsis or active malignancy
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Known increased infection risk due to underlying immunosuppressed state which includes:
- Prior organ or hematopoietic stem cell transplant
- Neutropenia with absolute neutrophil count (ANC) <500 cells/ul at the time of study inclusion
- Known HIV infection with CD4 <200 cells/ul at the time of study inclusion
- On concomitant immunosuppressants or corticosteroid at a dose of prednisolone equivalent dose 10mg or more for more than 3 months
- Known history or active infective endocarditis
- On peritoneal dialysis or haemodialysis
- Documented pregnancy
Substudy 2
Inclusion Criteria:
- Age 65 years and above
- Written informed consents obtained
Exclusion Criteria:
- Known history of confirmed COVID-19 infection
- Known active sepsis or active malignancy
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Known increased infection risk due to underlying immunosuppressed state which includes:
- Prior organ or hematopoietic stem cell transplant
- Neutropenia with absolute neutrophil count (ANC) <500 cells/ul at the time of study inclusion
- Known HIV infection with CD4 <200 cells/ul at the time of study inclusion
- On concomitant immunosuppressants, chemotherapies or corticosteroid at a dose of prednisolone equivalent dose 10mg or more for more than 3 months
- Known history or active infective endocarditis
- On peritoneal dialysis or haemodialysis
- Known active malignancy
- Known terminal illness with life expectancy less than 3 months

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04884776
Contact: Joyce WY Mak, FHKAM | 3505 3307 | wingyanmak@cuhk.edu.hk | |
Contact: Amy Li | 26373225 | amyli@cuhk.edu.hk |
Hong Kong | |
Prince of Wales Hospital, Shatin | Recruiting |
Hong Kong, Hong Kong | |
Contact: Joyce WY Mak, FHKAM 3505 3307 wingyanmak@cuhk.edu.hk |
Principal Investigator: | Joyce WY Mak, FHKAM | Chinese University of Hong Kong |
Responsible Party: | Mak Wing Yan, Assistant Professor, Chinese University of Hong Kong |
ClinicalTrials.gov Identifier: | NCT04884776 |
Other Study ID Numbers: |
IMPACT Study |
First Posted: | May 13, 2021 Key Record Dates |
Last Update Posted: | August 4, 2021 |
Last Verified: | July 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
COVID-19 Respiratory Tract Infections Infections Pneumonia, Viral Pneumonia Virus Diseases |
Coronavirus Infections Coronaviridae Infections Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases |