 Prospective phase II, open-label, single center study in which each experimental rifapentine regimen is evaluated using a two-stage design. Adults HIV-negative, or HIV-positive with CD4 200 cellscu mm suspected to have pulmonary tuberculosis who meet eligibility criteria will be randomized to receive one of three intensive phase regimens. Intensive phase regimens will consist of once daily isoniazid, pyrazinamide, and ethambutol, plus one of the following: rifampin 600 mg once daily OR rifapentine 450 mg once daily OR rifapentine 600 mg once daily. Randomization will be stratified by presenceabsence of cavitation on baseline chest radiograph. In Stage 1, 15 subjects will be randomized to each arm, following which there will be an enrollment pause for efficacy and safety assessment. Any rifapentine regimen for which fewer than 6 of 11 evaluable participants have week 8 culture conversion will be discarded. 