Switching from TDF to TAF in HIV/HBV co-infected individuals with renal dysfunction - a prospective cohort study.

BACKGROUND Whereas tenofovir disoproxil fumarate (TDF) can lead to renal adverse events, tenofovir alafenamide (TAF) has a more favorable renal safety profile. However, the impact of replacing TDF with TAF on renal function and liver parameters among HIV/hepatitis B virus (HBV) co-infected individuals with renal dysfunction remains unclear. METHODS We included all participants from the Swiss HIV Cohort Study with an HIV/HBV-coinfection who switched from TDF to TAF and had an estimated glomerular filtration rate (eGFR) <90 mL/min/1.73m and a suppressed HIV viral load (<200 cp/mL). We assessed changes in eGFR, urine protein-to-creatinine ratio and alanine aminotransferase (ALT) after one year using mixed-effect models with interrupted time-series. RESULTS Among 106 participants (15.1% women, median age 53 years), eGFR was 60-89 mL/min/1.73m in 84 (79.2%) and <60 mL/min/1.73m in 22 (20.8%) individuals at the time of switch. One year after the switch from TDF to TAF, individuals with an eGFR between 60-89 mL/min/1.73m experienced increases in eGFR of 3.2 mL/min/1.73m (95% confidence interval [CI] 1.2 to 5.2), while those with an eGFR <60 mL/min/1.73m experienced improvements of 6.2 mL/min/1.73m (95% CI 2.4 to 10.0). Urine protein-to-creatinine ratio decreased overall (-6.3 mg/mmol, 95% CI -10.0 to -2.7), and ALT levels declined in patients with elevated baseline levels (-11.8 IU/L, 95% CI -17.3 to -6.4) one year after replacing TDF with TAF. CONCLUSIONS Switching from TDF to TAF among HIV/HBV-coinfected individuals with renal impairment led to improvements in eGFR, a decline in proteinuria, and to ALT normalization in those with elevated ALT levels.