Coadministration of Atripla (efavirenz 600 mg, emtricitabine 200 mg, tenofovir-DF 300 mg, daily, and rifapentine (900 mg once weekly for 3 weekly administrations) was studied in 12 HIV-infected subjects. Overall the steady state exposures of efavirenz, emtricitabine and tenofovir were comparable with and without weekly rifapentine. Efavirenz AUC, Cmax and Cmin decreased by 14%, 18% and 15%, respectively. Emtricitabine AUC, Cmax and Cmin decreased by 7%, 5% and 3%, respectively. Tenofovir AUC and Cmin decreased by 9% and 13%, whereas Cmax was unchanged. Coadministration was well tolerated and no clinically significant modifications of CD4 cell counts or viral loads were observed. Thus, the concomitant use of rifapentine according to latent tuberculosis infection regimen (900 mg weekly ) and efavirenz-based ART is possible with no dose adjustment.