Utility of Lactoferrin as an Adjunct Therapeutic Agent for COVID-19

There is currently no clinically proven specific antiviral agent available for SARS-CoV-2 infection. Supportive treatment, including oxygen therapy, remains the most important management strategy. Since its discovery, lactoferrin and its related peptides are mainly considered to be important non-specific host defense molecules against a broad range of viruses including SARS-CoV, which is closely related to SARS-CoV-2 that causes COVID-19. Lactoferrin has been found to experimentally inhibit viral entry in murine coronavirus, and human coronaviruses hCOV-NL63 and pseudotyped SARS-CoV. Besides reducing viral entry, lactoferrin can also suppress virus replication after the viral entry. Another major aspect of lactoferrin bioactivity relates to its immunomodulatory and anti-inflammatory functions. Current thinking suggests that mortality from COVID-19 is not simply due to viral infection but is a result of a cytokine storm associated with hyper-inflammation leading to acute respiratory distress and subsequent mortality. A cytokine profile in severe COVID-19 cases is characterized by increases in cytokines and acute phase reactants and ferritin. In this regard, lactoferrin was demonstrated to reduce IL-6, TNF a, and downregulate ferritin in experimental settings simulating sepsis. In this study, we aim to study the potential application of lactoferrin against SARS-CoV-2 and propose the possibility of using different doses of supplemental lactoferrin as a potential adjunct treatment for COVID-19.