The proposed study aims to further evaluate the safety and immunogenicity of a candidate S. aureus vaccine NDV-3A, as well as its efficacy against acquisition of S. aureus

The investigators will conduct a Phase 2 clinical trial to evaluate the safety, immunogenicity, and efficacy of candidate vaccine NDV-3A (NovaDigm Therapeutics, Inc.) to prevent incident nasal acquisition of S. aureus among a population of military recruits at increased risk for S. aureus colonization and disease. Colonization is a risk factor for skin and soft tissue infection (SSTI), and the anterior nares is an important reservoir for S. aureus. Use of S. aureus nasal colonization (specifically, incident nasal colonization with S. aureus post-vaccination) as a primary endpoint will allow the investigators to pursue a statistically-valid and meaningful parameter related to S. aureus SSTI. The proposed trial may yield evidence to warrant evaluation of NDV-3A efficacy against SSTI in a large-scale, Phase 2/3 trial in this high risk population.

Inclusion Criteria:

• Active duty, male subject, 17-35 years of age, inclusive, at the time of screening.
• Assigned to one of the selected companies/battalions
• Informed of the nature of the study and has agreed to and is able to read, review, and sign the informed consent document prior to screening.
• Free of known significant health problems as established by the requirements to be enrolled in a military training program before entering into the study.
• Agrees to be reachable by phone, email or letter at 6 months post-vaccination.

Exclusion Criteria:

• Reports receiving any investigational drug, investigational vaccine, or investigational device within 30 days prior to dosing; subjects will be allowed to receive routine vaccinations associated with training and any other prescribed medications not in the exclusion criteria.
• Presence of clinically significant SSTI (e.g., cellulitis, abscess) at screening or other skin or skin structure infections that would confound the interpretation of clinical response.
• Reports a history of allergic response(s), anaphylaxis, or other serious reactions to previous vaccinations.
• Reports a history of allergies to yeast
• Reports a history of anaphylaxis or other serious reactions to aluminum.
• Reports a history of autoimmune disease (psoriasis, etc.)
• Seropositive for HIV antibody.
• Reports the use of any immunosuppressive drugs, including systemic corticosteroids (more than 14 days at a dose of >20 mg/day prednisone or equivalent), within 4 weeks prior to dosing.
• Reports receiving any blood products within 3 months prior to dosing.
• Reports donating blood/plasma within 28 days prior to dosing.
• Illness causing temperature ≥ 100.4°F
• Evidence of abnormal, unresolved laboratory results in the subject's medical record for the following tests: hemoglobin, white blood cell count, platelet count, creatinine, and alanine aminotransferase
• Any other medical and/or social reason which, in the opinion of the investigator(s), would increase the subject's risk of having an adverse reaction as a result of participation in the study.

Sponsor, principal investigator and study site are all blinded but can access key if safety issues require unblinding