The study will include HIV/HBV-coinfected participants of the Swiss HIV Cohort Study (SHCS) who are under active care and have been on a stable, TDF-containing ART regimen for at least 6 months. Only patients with an estimated glomerular filtration rate (GFR) between 30 ml/min and 90 ml/min will be included. All individuals who agree to participate will be switched from a TDF-containing ART regimen to a TAF-containing triple ART regimen at week 0 and will be followed for 48 weeks after the treatment change.