Phase 2a Clinical Trial of ID93+GLA-SE Vaccine in BCG-vaccinated Healthy Healthcare Workers

Inclusion Criteria: 1. Male or female who is ≥19 and \<65 years of age. 2. Healthcare workers who are QuantiFERON®-TB Gold Plus negative (not latently infected with Mtb) at screening. 3. Able to comply with the scheduled visits, and are expected to continue working in the current medical institution and be available for a continuous follow-up by the investigator via provided contact information. 4. Only for female subjects of childbearing potential: * Must be HCG-negative from serum or urine pregnancy test, at screening; * Agreed to use one of the following acceptable birth control methods to avoid pregnancy until the end of study (Visit 9): hormonal contraceptives, intrauterine device (IUD) or intrauterine system (IUS), tubal ligation, or combination of barrier methods (combined use of barrier methods such as male condoms, female condoms, cervical cap, diaphragm, sponge, or implant). 5. History of BCG vaccination that is confirmed through medical examination (i.e., asking a subject about his/her condition) or presence of a scar. 6. Body mass index (BMI) ≥19 and ≤33 (kg/m\^2) at screening 7. Subjects who understand the study procedures, and voluntarily decide to participate in the study and sign the informed consent form.. Exclusion Criteria: 1. History of positive tuberculin skin test or positive QuantiFERON®-TB results. 2. History of severe chronic disease that may compromise the safety of the subject during the study (e.g., impairment of pulmonary function from tuberculosis infection or other pulmonary disease; chronic illness with signs of cardiac or renal failure; suspected progressive neurological disease or uncontrolled epilepsy). 3. Body temperature ≥ 38℃ at the time of randomization or within 24 hours before randomization, from acute fever, acute respiratory diseases, or active infection. 4. Malignant tumors or a history of malignant tumors. 5. Plans to have surgery during the study period. 6. Impaired immune functions including autoimmune disease or immunodeficiency disease. 7. History of Guillain-Barre syndrome. 8. Subjects with a history of anaphylaxis or severe allergic reaction to vaccines, eggs, or other allergens. 9. Subjects living with a household member who has active TB or infectious TB. 10. Clinically significant abnormal laboratory values for any of the following tests conducted in the study center, prior to randomization: * Hemoglobin, hematocrit, absolute neutrophil count, absolute lymphocyte count, or platelet count: \< LLN (lower limit of normal) * White blood cell count: \>ULN (upper limit of normal) or \<LLN (lower limit of normal) (i.e., must be within normal limits) * ALT, AST, total bilirubin, alkaline phosphatase, creatinine, or blood urea nitrogen (BUN): \>ULN (upper limit of normal) 11. Received an immunosuppressant, immunity-modifying drug, or other treatment that may affect the immune system including cytotoxic anti-cancer agents or radiotherapy, within 3 months before the randomization. 12. Use of systemic steroids (equivalent to daily prednisone ≥ 15mg/day for more than 14 days), inhaled or intranasal steroids, within 3 months before randomization; however, use of topical corticosteroids are acceptable, regardless of dose. 13. Use of immunoglobulin or blood products within 3 months before randomization or plans to use them during the study period. 14. Human Immunodeficiency Virus (HIV) positive at screening. 15. Subjects with chronic hepatitis (e.g., hepatitis B core antibody or hepatitis C antibody positive) at screening. 16. Unable to discontinue current chronic drug therapy such as thyroxin, insulin, or other medications with hepatotoxicity or myelotoxicity; however, estrogen and progesterone replacement therapy or contraceptives, and topical medications are acceptable. 17. Pregnant or lactating. 18. Received other vaccines within 4 weeks before screening or plans to receive them from the day of screening to 4 weeks after the last vaccination with the Investigational Product or within 4 weeks before the End Visit. 19. Received other investigational drugs within 4 weeks before screening. 20. Subjects deemed ineligible by investigator based on other reasons.