Tenofovir alafenamide and rifabutin co-administration does not lead to loss of HIV-1 suppression: A retrospective observational study

Abstract

Objectives: Tenofovir alafenamide (TAF) is a preferred nucleotide reverse transcriptase inhibitor used in the treatment of HIV. Co-administration of TAF with rifabutin (RFB) is not recommended due to concerns that RFB decreases TAF gastrointestinal absorption. The objective of this study was to determine the efficacy of antiretroviral therapy regimens that include the co-administration of TAF and RFB.

Methods: Persons with HIV (PWH) who received TAF-RFB co-administration for ≥1 month were identified retrospectively. The primary outcome was the maintenance of HIV viral load <200 copies/mL (cpm) for those already on HIV therapy at RFB initiation, or suppression of viral load to <200 cpm for those with unsuppressed HIV viral load prior to TAF-RFB co-administration.

Results: Twenty-two PWH met the inclusion criteria. Four out of five patients (80%) maintained a viral load <200 cpm and 15/17 (88%) achieved a viral load <200 cpm during TAF-RFB co-administration. After the exclusion of patients who self-discontinued therapy or were lost to follow-up, 19/19 (100%) met the combined primary endpoint of HIV viral load <200 cpm.

Conclusions: This study suggests that TAF-RFB co-administration may be effective despite concerns that RFB could reduce TAF absorption.

Keywords: Co-administration; HIV; Rifabutin; Tenofovir alafenamide.

Fig. 1.

Percentage of participants who achieved or maintained an HIV viral load <200 cpm (light grey) or <50 cpm (dark grey) during TAF–RFB co-administration, according to baseline viral load at the start of co-administration. The percentage of participants with viral suppression at the end of rifabutin treatment was available for 18 participants (combined from both groups). Abbreviations: VLviral load; cpmcopies per ml.