Study to Evaluate the Efficacy of GlaxoSmithKline (GSK) Biologicals' Candidate Tuberculosis (TB) Vaccine in Adults

The purpose of this study is to evaluate the protective efficacy of two doses of GSK Biologicals' candidate TB vaccine against pulmonary TB, as compared to placebo. The efficacy will be evaluated in adults living in TB endemic countries and aged 18 - 50 years because pulmonary TB occurs frequently in these countries and age range. In addition, the safety and immunogenicity of the candidate tuberculosis vaccine will be evaluated in a subset of volunteers.

Case Definitions:

• First case definition: A subject with clinical suspicion of pulmonary TB disease, with MTB complex identified from a sputum specimen, taken before initiation of TB treatment, by Xpert MTB/RIF and/or microbiological culture and confirmed HIV-negative at the time of TB diagnosis.

• Second case definition: A subject with clinical suspicion of pulmonary TB disease, with MTB complex identified from a sputum specimen, taken before initiation of TB treatment, by Xpert MTB/RIF and confirmed HIV-negative at the time of TB diagnosis.

• Third case definition: A subject with clinical suspicion of pulmonary TB disease, with MTB complex identified from a sputum specimen, taken up to four weeks after initiation of TB treatment, by Xpert MTB/RIF and/or microbiological culture and confirmed HIV-negative at the time of TB diagnosis.

• Fourth case definition: A subject with clinical suspicion of pulmonary TB disease, with MTB complex identified from a sputum specimen, taken up to four weeks after initiation of TB treatment, by Xpert MTB/RIF and/or microbiological culture.

• Fifth case definition: A subject for whom a clinician has diagnosed TB disease and has decided to treat the patient with TB treatment.