Improved tuberculosis outcomes with daily vs. intermittent rifabutin in HIV-TB coinfected patients in India.

SETTING: Y R Gaitonde Centre for AIDS Research and Education, Chennai, India. OBJECTIVE: To compare anti-tuberculosis treatment outcomes in individuals with human immunodeficiency virus (HIV) and tuberculosis (TB) co-infection on atazanavir/ritonavir (ATV/r) antiretroviral therapy (ART) plus daily rifabutin (RBT) 150 mg with those on ATV/r plus thrice-weekly RBT 150 mg. DESIGN: A retrospective study was conducted of two HIV-TB co-infected cohorts between 2003 and 2014. Basic demographic and TB outcome data were obtained from an electronic database and patient records. The χ(2) and Fisher's exact test were used to compare daily and intermittent RBT treatment groups. RESULTS: Of 292 individuals on an ATV/r-based ART regimen plus RBT, 118 (40.4%) received thrice-weekly RBT and 174 (59.6%) daily RBT. Patients in the two RBT treatment groups were similar in sex, age, previous history of TB, site of TB and acid-fast bacilli smear status. More individuals in the daily vs. the intermittent RBT group achieved clinical cure (73.0% vs. 44.1%, P < 0.001), with no significant differences in relapse/recurrence or all-cause mortality between groups. CONCLUSION: There were higher rates of clinical TB cure in individuals on a boosted protease inhibitor-based ART regimen with daily RBT compared to intermittently dosed RBT. Optimal RBT dosing in this setting requires further investigation.