Incidence and severity of drug interactions before and after switching antiretroviral therapy to bictegravir/emtricitabine/tenofovir alafenamide in treatment-experienced patients
Abstract Background Switching antiretroviral therapy (ART) in people living with HIV (PLWH) can influence their risk for drug-drug interactions (DDIs). The purpose of this study was to assess changes in the incidence and severity of DDIs among PLWH who switched their ART to bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF). Methods This was a multicenter retrospective cohort study of PLWH on ART and at least one concomitant medication (CM) who switched to BIC/FTC/TAF between 3/2018 and 6/2019. Using the University of Liverpool’s HIV Drug Interaction Database, two DDI analyses were performed for each patient. The first assessed patients’ pre-switch ART regimens with their CM list. The second assessed the same CM list with BIC/FTC/TAF. Each ART-CM combination was given a score of zero (no or potential weak interaction), one (potential interaction), or two (contraindicated interaction). A paired t-test analyzed changes in total DDI scores following ART switches and linear regression examined factors contributing to DDI score reductions. Results Among 411 patients, 236 (57%) had at least one DDI present at baseline. On average, baseline DDI scores were 1.4 (SD 1.8) and decreased by 1-point (95% CI -1.1,-0.8) after patients switched to BIC/FTC/TAF (p < 0.0001). After adjusting for demographics, baseline ART and CM categories, switching to BIC/FTC/TAF led to significant DDI score reductions in patients receiving CMs for cardiovascular disease, neurologic/psychiatric disorders, chronic pain, inflammation, gastrointestinal/urologic conditions and conditions requiring hormonal therapy. Conclusion Treatment-experienced PLWH eligible to switch their ART, may experience significant declines in their number and severity of DDIs if switched to BIC/FTC/TAF.