Study Population A total of at least 1155 participants with multi-drug resistance tuberculosis (MDR-TB) including patients with rifampicin-resistant and isoniazid-sensitive TB, will be recruited from sites in a number of countries. They will be randomised to either Regimen A, Regimen B, Regimen C, or Regimen D in a ratio 1:2:2:2 (i.e. 165 allocated to Regimen A, 330 allocated to Regimen B, 330 allocated to Regimen C, and 330 allocated to Regimen D).