A booster dose of a 3-antigen Staphylococcus aureus vaccine (SA3Ag) was assessed.
SA3Ag is a novel multiantigen vaccine that targets S. aureus virulence factors.
Immune response to the 1st vaccination persisted for 12 months in adults ≤85 years.
Little or no additional immune response induced by booster dose given at Month 6.
Injection site reactions post-booster more frequent and severe but self-limiting.