Dose-Escalation Study to Evaluate the Safety and Immunogenicity of MTBVAC Vaccine in Comparison With BCG Vaccine.

Inclusion Criteria: * Subjects who the Investigator believes that they can and will comply with the requirements of the protocol * Subjects who have no evidence of exposition to BCG as demonstrated by a ELISPOT PPD assay along with no history of BCG vaccination and no BCG scar * A male or female between, and including, 18 and 45 years of age at the time of the vaccination. * Written informed consent obtained from the subject prior to any study procedure. * If the subject is female, she must be of non-childbearing potential, or if she is of childbearing potential, she must practice adequate contraception * Clinically acceptable laboratory values for blood tests. * Seronegative for human immunodeficiency virus 1 and -2 (HIV-1/2) antibodies, p24 antigen, hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) antibodies. * No evidence of pulmonary pathology as confirmed by chest X-ray. * No history of extrapulmonary TB. * No history of previous contact with M. tuberculosis (latent tuberculosis) as demonstrated by a negative ELISPOT Tb (ESAT-6, CFP10) assay. Exclusion Criteria: * History of allergic reactions (significant IgE-mediated events) or anaphylaxis to previous immunisations (any vaccine). * History of allergic disease or reactions * History of previous administration of experimental Mycobacterium tuberculosis vaccines. * Use of any investigational or non-registered product (drug or vaccine) in another experimental protocol other than the study vaccines within 30 days preceding the vaccination, or planned use during the study period. * Any chronic drug therapy to be continued during the study period. * Chronic administration of immunosuppressors or other immune-modifying drugs. * Administration of any immunoglobulins, any immunotherapy and/or any blood products within the three months preceding the vaccination, or planned administrations during the study period. * Any confirmed or suspected immunosuppressive or immunodeficient condition (including HIV) based on medical history and physical examination. * Any condition or history of any acute or chronic illness or medication which, in the opinion of the Investigator, may interfere with the evaluation of the study objectives. * A family history of congenital or hereditary immunodeficiency. * A stay of more than 2 months in a highly endemic area (e.g. Eastern Europe (Romania, Bulgaria) and low-income countries) within 6 months prior to the screening visit or travel of more than 2 months foreseen in an area of high endemicity after the enrolment into the study. * History of any neurologic disorders or seizures. * History of chronic alcohol consumption and/or drug abuse. * Major congenital defects. * Pregnant or lactating female. * Female planning to become pregnant or planning to discontinue contraceptive precautions.