Intranasal Application Of Lactococcus Lactis W 136 Bacteria Early In COVID 19 Infection May Have A Beneficial Immunomodulatory Effect: A Proof-Of-Concept Study

JustificationStimulation of early innate anti-viral responses during the early phase of SARS-COV-2 infection oxygen may improve evolution of illness and late pulmonary complications. This may be possible using a TLR agonist such as a probiotic bacterium possessing desirable immunomodulatory properties. MethodWe performed a non-contact, open-label, prospective randomized clinical trial comparing intranasally applied Lactococcus lactis W136 with saline irrigation alone in patients within 96 hours of diagnosis of SARS-COV-2 infection not requiring supplemental oxygen. ResultsTwenty-three of a planned forty participants aged 18-59 without comorbidities were recruited. Irrigation with intranasal L lactis W136 twice-daily for fourteen days of was associated with a nasal response characterised by increase in the symptom of Facial and Throat pain/discomfort, and with a lesser severity in symptoms of i) Fatigue ii) Olfactory dysfunction and iii) Breathlessness. Safety and tolerability were good, with no acute infections or severe deteriorations. InterpretationFacial and throat pain may correspond to postulated mechanism of action corresponding to activation of innate defences with antiviral effects and may explain the potentially protective effects seen. Intranasal L lactis W136 irrigations may thus represent a potentially inexpensive, safe, and easily scalable non-antigen based therapeutic for the continuing global SARS-COV-2 pandemic. Data availability statementData is available on request from the senior author, Dr Desrosiers: martin-yvon.desrosiers.med@ssss.gouv.qc.ca FundingThis work was supported with internal funds from the Desrosiers laboratory at the Centre de Recherche du Centre Hospitaller de lUniversite de Montreal (CRCHUM). Competing InterestsDr Desrosiers holds equity in Probionase Therapies inc., Which commercialises Lactococcus lactis W136 for chronic rhinosinusitis.