Lactoferrin inhibits SARS-CoV-2 infection through multiple complementary mechanisms: binding to viral HSPG (heparan sulfate proteoglycan) attachment sites, directly blocking spike protein-ACE2 interaction, reducing inflammatory cytokine production, and enhancing NK cell antiviral surveillance. The Campione 2021 RCT is the landmark clinical validation of these mechanisms.

Is lactoferrin a substitute for COVID-19 vaccination?

No. COVID-19 vaccines provide adaptive immune protection (antibodies, T cell memory) against severe disease. Lactoferrin provides innate immune and direct antiviral support. They are complementary — neither replaces the other.

Does lactoferrin work against COVID-19 variants?

HSPG binding and NK cell activation mechanisms are likely to retain activity across variants (HSPG binding sites and innate immune mechanisms are not spike-variant-specific). ACE2-binding blocking may be variant-affected. Complete variant-specific efficacy data is not available.