The purpose of this study is to evaluate the safety and immunogenicity of a single vaccination of an investigational vaccine against Staphylococcus aureus (SA4Ag) in healthy adults aged 18 to <65 years.

Inclusion Criteria: 1. Evidence of a personally signed and dated informed consent document (ICD) indicating that the subject has been informed of all pertinent aspects of the study. 2. Subjects who are willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures, including daily completion of the e-diary for 10 days after study vaccination. 3. Healthy male and female subjects, aged 18 to <65 years at enrollment, as determined by medical history, physical examination, and the clinical judgment of the investigator to be eligible for the study. Subjects with preexisting chronic medical conditions determined to be stable may be included. 4. Male and female subjects of childbearing potential and at risk for pregnancy must agree to use a highly effective method of contraception throughout the study. 5. Subject must be able to be contacted by telephone during study participation.

Exclusion Criteria: 1. Unstable chronic medical condition or disease requiring significant change in therapya or hospitalization for worsening disease within 3 months before receipt of investigational product. 2. Serious chronic medical disorders including metastatic malignancy, severe chronic obstructive pulmonary disease (COPD) requiring supplemental oxygen, end-stage renal disease with or without dialysis, clinically unstable cardiac disease, or any other disorder that in the investigator's opinion precludes the subject from participating in the study. 3. Congenital or acquired immunodeficiency disorder, rheumatologic disorder, or other illness requiring chronic treatment with known immunosuppressant medications, including monoclonal antibodies, within the year prior to enrollment or the use of systemic corticosteroids (equivalent of ≥10 mg/day of prednisone) for >14 days within 30 days prior to study enrollment. 4. History of leukemia, lymphoma, or underlying bone marrow disorder (eg, myelodysplasia, myeloma, myeloproliferative disorder) or history of bone marrow transplant. 5. Malignancy that required treatment with chemotherapy, immunotherapy, radiation therapy, or other antineoplastic target therapies within 24 months prior to study enrollment. 6. Any infection proven or suspected to be caused by S. aureus within 6 months preceding study vaccination. 7. Previous administration of S. aureus vaccine or S. aureus/Candida vaccine. 8. Any contraindication to vaccination or vaccine components, including previous anaphylactic reaction to any vaccine or vaccine-related components. 9. Bleeding diathesis or condition associated with prolonged bleeding time that would contraindicate intramuscular injection. 10. Donation of blood volume of 250 mL or greater (excluding protocol-required blood collection) or donation of plasma within 3 months prior to enrollment through conclusion of the study. 11. Receipt of blood products or immunoglobulins (including monoclonal antibodies) within 6 months before enrollment or anticipated through conclusion of the subject's participation. 12. Subjects who are investigational site staff members directly involved in the conduct of the study and their family members, site staff members otherwise supervised by the investigator, or subjects who are Pfizer employees directly involved in the conduct of the study. 13. Participation in other studies involving investigational drug(s) (Phases 1-4) within 30 days before the current study begins and/or during study participation. Participation in observational studies is permitted. 14. Pregnant female subjects; breastfeeding female subjects; male subjects with partners currently pregnant; male and female subjects of childbearing potential and at risk for pregnancy who are unwilling or unable to use a highly effective method of contraception as outlined in this protocol for the duration of the study. 15. Residence in a nursing home or long-term care facility or requirement for semiskilled nursing care. An ambulatory subject who is a resident of a retirement home or village is eligible for the trial. 16. Subjects with known active disease with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and/or hepatitis C virus (HCV). 17. Other severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the subject inappropriate for entry into this study.