 WBA is an ex vivo model for measuring the combined effects of administered drugs, host factors and strain factors on mycobacterial killing. If performed in parallel with PK measurements, the method can be used to evaluate the effect of drugs throughout the dosing cycle. This study aims to compare different doses of rifampicin in the WBA model, compare activity of rifampicin on WBA by different mycobacterium tuberculosis strain types and assess the host immune response following drug administration. 