A First in Human Trial to Assess the Safety and Immunogenicity of LTB-SA7 Vaccine Against Staphylococcus Aureus.

Inclusion Criteria:

1. Good general health by medical history, laboratory findings and physical examinationas judged by the investigator before receiving the first injection.

2. Participant who is willing and able to comply with the requirements of the protocol (e.g., completion of the diary forms, return for follow-up visits).

3. Signed written informed consent obtained from the participant.

4. Participants between 18-50 years (inclusive) of age at the time of the firstinjection.

5. Negative urine pregnancy test for women of childbearing potential (WOCBP).

6. WOCBP must be willing to use a highly effective method of contraception during thetrial.

Exclusion Criteria:

1. Health conditions that, in the opinion of the investigator, may interfere withoptimal participation in the trial or place the participant at increased risk ofadverse events.

2. Any deviation from the normal range in biochemistry or hematology blood testsclinically significant in the opinion of the investigator, measured at the screeningvisit.

3. Clinically significant abnormalities on physical examination.

4. Suspected or known hypersensitivity (including allergy) to any of the vaccinecomponents or medical equipment whose use is foreseen in this trial.

5. History of allergy to any vaccine.

6. Clinical conditions representing a contraindication to intramuscular vaccination andblood draws (e.g., coagulation disorder).

7. Known or suspected impairment of immunological function e.g., documented HumanImmunodeficiency Virus (HIV) infection, asplenia/splenectomy, or history ofautoimmune disease or lymphoproliferative disorder.

8. Positive blood test for HBsAg, HCV, HIV-1/2.

9. History of systemic administration of immunosuppressive drugs, i.e.,corticosteroids, (PO/IV/IM) within the last month prior to vaccination or for morethan 14 consecutive days within 3 months prior to vaccination, until the last bloodsampling visit (i.e., prednisone or equivalent ≥20 mg/day). Inhaled and topicalsteroids are allowed.

10. Administration of antineoplastic and immune-modulating agents or chemotherapy within 3 months prior to vaccination.

11. Planned or actual administration of any licensed vaccine within 14 days prior toeach vaccination and 30 days after each vaccination. Note: In case an emergency massvaccination for an unforeseen public health threat (e.g.: a pandemic) is organizedby the public health authorities, the time period described above can be reduced, ifnecessary, for that vaccine provided it is licensed or authorized and used accordingto the local governmental recommendations and provided a written approval of theSponsor is obtained.

12. Concurrently participating in another clinical trial, at any time during the trialperiod, in which the participant has been or will be exposed to an investigationalor a non-investigational interventional vaccine/ product (pharmaceutical product).

13. Body Mass Index (BMI) ≤19 or ≥35

14. History of any chronic or progressive disease that according to judgment of theinvestigator could interfere with the trial outcomes or pose a threat to theparticipant's health.

15. Received an investigational or non-registered product (medicinal drug or vaccine),other than the trial vaccine within 3 months prior to 1st administration of trialvaccine, or planned use during the trial period.

16. Administration of immunoglobulin and/or any blood products within the three monthspreceding the first dose of trial vaccine.

17. Blood donation equal or greater to 500 mL of blood drawn within 3 months precedingthe first or second vaccination or planned during the trial period as reported bythe participant.

18. Use of any systemic antibiotic therapy within 1 week preceding each vaccination.

19. Participants with an elective surgical intervention, planned during the trial perioduntil 1 month after 2nd vaccination.

20. Female participants lactating, pregnant, or intending to become pregnant as reportedby the participant.