- Post-treatment Period (Visits 60 to 64 [Days 57 to 84]) Enrolled patients (those accepted into the screening period of the trial who signed an informed consent form) will be stratified at randomization by extent of pulmonary TB; an equal number of patients with and without cavities visible in the lung fields on baseline chest radiograph will be allocated to each treatment group. A total of 430 male or female patients aged 18 to 64 years, inclusive, with pulmonary, sputum culture-positive MDR TB (TB caused by Mycobacterium tuberculosis strains resistant to at least isoniazid and rifampicin) or with sputum smears positive for acid fast bacilli (AFB) and a positive rapid test for rifampicin resistance on direct sputum within 60 days prior to the expected date of enrollment. Patients with positive AFB smears and a positive rapid rifampicin resistance test will be enrolled as presumptively culture positive and withdrawn as ineligible if they are confirmed to not have sputum culture positive MDR TB.