Pharmacokinetics of Rifabutin Combined With Antiretroviral Therapy in Patients With TB/HIV Co-infection in South Africa

Inclusion Criteria: * Pulmonary tuberculosis (proven by AFB positive sputum or culture) * Having completed and adhered to 6 wks of intensive phase TB chemotherapy * Positive HIV antibody and CD4 count \>50 /mm3 and \<=200 * Weight \> 50 kg * No ART in the preceding 3 months * No more than 2 weeks or ART previously * No grade 3 or 4 clinical or laboratory findings * Negative pregnancy test and appropriate contraceptive measures during the duration of the trial for female of childbearing age * Having a firm home address that is readily accessible * Karnofsky score\>=80% Exclusion Criteria: * History of TB within the 3 years preceding the presenting episode of TB * Previous treatment for MDR TB * Concomitant OI requiring additional anti-infectious treatment * Formal contraindication to any drug used in the trial * Diabetes mellitus requiring drug treatment * Recreational drug or alcohol abuse * History of drug hypersensitivity to TB or related medications * Interrupted TB therapy for more than 1 week * Less than 90% adherent to first 6 weeks of intensive phase chemotherapy * Mental illness that could impair ability to give informed consent or result in poor adherence to trial protocol and therapy * Neutropenia \<1200 /L, anaemia \<6.8 g/dL, liver function test \> grade 2 * Requiring concomitant medications that may potentially interact with study drugs * Pregnant or lactating women * Karnofsky score \>80% * Any condition rendering the patient unable to understand the nature, scope, and possible consequences of thes study and to provide consent