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The Effect of Probiotic Supplementation on SARS-CoV-2 Antibody Response After COVID-19

Not Applicable
Completed
Conditions
Covid19
Interventions
Dietary Supplement: L. reuteri DSM 17938 + vitamin D
Dietary Supplement: Placebo + vitamin D
Registration Number
NCT04734886
Lead Sponsor
Örebro University, Sweden
Brief Summary

This study will explore how a well-known probiotic strain L. reuteri DSM 17938 impacts SARS-CoV-2 specific antibody response upon and after infection in healthy adults.

Detailed Description

After giving their informed consent, the study subjects will complete screening procedures to assess their eligibility for the study (Visit 1). Participants deemed suitable for the study will be randomized into two study arms (placebo, probiotic) before undergoing a baseline visit (Visit 2) before the start of the intervention period. During the 6-month intervention period, the participants will attend study visits at 3 months (Visit 3) into the intervention as well as at the end of intervention (at 6 months, Visit 4). Blood, saliva, and faecal samples will be collected at visits 2-4. In addition to sampling, during the whole intervention period, the participants will fill out a weekly questionnaire in which they are asked to record any possible symptoms of COVID-19. The participants' dietary habits are assessed via a food frequency questionnaire (FFQ) before the start of the intervention period. Also, the participants are asked to maintain their habitual diet and lifestyle as well as not to consume any other probiotic or prebiotic supplements.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
161
Inclusion Criteria
  1. Signed informed consent
  2. Age between 18-60
Exclusion Criteria
  1. Previous diagnosis of COVID-19 (by positive PCR) or previous confirmation of seropositivity to SARS-CoV-2
  2. Body Mass Index over 35 or under 16
  3. Current diagnosis of cancer or ongoing cancer treatment in the last 12 months
  4. Diabetes mellitus
  5. Cardiovascular disorder in need of pharmaceutical treatment
  6. Chronic kidney disease
  7. Chronic lung disease with decreased lung capacity
  8. Chronic liver disease with liver cirrhosis
  9. Current diagnosis of dementia, severe depression, major psychiatric disorder, or other incapacity for adequate cooperation
  10. Chronic neurological/neurodegenerative disease (e.g. Parkinson's disease)
  11. Decreased function of the adrenal cortex (e.g. Addison's disease)
  12. Autoimmune disease (e.g. rheumatoid arthritis)
  13. Chronic pain syndromes (e.g. fibromyalgia)
  14. Pregnancy or breast-feeding
  15. Immunodeficiency due to disease or ongoing medical treatment
  16. Regular intake of anti-inflammatory and/or other immunosuppressive medication within the last 3 months
  17. Use of anti-depressants within the last 3 months
  18. Antimicrobial treatment within the last 12 weeks before baseline sampling
  19. Regular intake of probiotics, as well as nutritional supplements or herb products that might affect intestinal function within the last 4 weeks if the investigator considers that those could affect study outcome
  20. Inability to maintain current diet and lifestyle during the study period
  21. Alcohol or drug abuse
  22. Any clinically significant present or past disease/condition which the investigator considers to possibly interfere with the study outcome or increase the risk for severe form of COVID-19

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
L. reuteri DSM 17938L. reuteri DSM 17938 + vitamin DProbiotic compound
PlaceboPlacebo + vitamin DPlacebo compound
Primary Outcome Measures
NameTimeMethod
SARS-CoV-2 specific antibodies3 months (interim analysis) or at 6 months

Change in SARS-CoV-2 specific IgG/IgM antibodies in serum between the study arms

Secondary Outcome Measures
NameTimeMethod
Duration of COVID-19 symptoms measured by a weekly symptom questionnaire3 months + 6 months

Change in duration of COVID-19 related symptoms between the study arms

Maintenance of SARS-CoV-2 seroconversion in seropositive individuals3 months + 6 months

Change in the maintenance of SARS-CoV-2 specific IgG/IgM antibody levels in serum between the study arms

Intestinal inflammation3 months + 6 months

Change in faecal calprotectin levels between the study arms

Indirect marker of intestinal permeability3 months + 6 months

Change in LBP levels in plasma between the study arms

Blood group A antigen antibodies3 months + 6 months

Change in anti-A levels in serum between the study arms

T cell activation3 months + 6 months

Change in the proportion of SARS-CoV-2 specific T cells of all T cells in blood between the study arms

Severity of COVID-19 symptoms measured by Ordinal Scale for Clinical Improvement (scale 0-7, a lower score corresponds to a better outcome)3 months + 6 months

Change in severity of COVID-19 related symptoms between the study arms

Secretory IgA (sIgA) antibodies3 months + 6 months

Change in sIgA levels in saliva between the study arms

Tn antigen antibodies3 months + 6 months

Change in anti-Tn levels in serum between the study arms

Cytokines3 months + 6 months

Change in TNF-a, IFN-y, IL-1B, IL-4, IL-6, IL-8, IL-10 levels in serum between the study groups

Intestinal barrier function3 months + 6 months

Change in I-FABP levels in plasma between the study arms

Blood group B antigen antibodies3 months + 6 months

Change in anti-B levels in serum between the study arms

Innate immune system activation3 months + 6 months

Change in high-sensitive C-reactive protein (hs-CRP) levels in plasma between the study groups

Total antibodies3 months + 6 months

Change in total IgG and IgM levels in serum between the study groups

B cell activation3 months + 6 months

Change in the proportion of SARS-CoV-2 specific B cells of all B cells in blood between the study arms

Trial Locations

Locations (1)

Örebro University

🇸🇪

Örebro, Örebro Län, Sweden

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