TDF Dose Adjustment VS. Switching to TAF in TDF-experienced CHB Patients With Renal Impairment

Tenofovir is a nucleotide analog drug that works against both Human immunodeficiency virus (HIV) and HBV. TDF and TAF are prodrug of Tenofovir. TAF has a higher plasma stability than TDF, which makes TDF require a higher dose to get the concentration of drugs in the liver equal to the amount of TAF. Previous studies have shown the effects of TAF once daily and TDF once daily on kidney function and bone mass. The efficacy of TAF in virus suppression is comparable to TDF, but the effect on the kidneys and bone mass from TAF has less side effects than TDF. In addition, changing the medication from TDF to TAF shows that kidney function tends to improve. Hepatitis B patients taking TDF have adjusted their dosage due to impair renal function, for example, from 1 time per day to every 48 hours or every 72 hours. This group of patients does not have a clear evidence-based recommendation for choosing a reduced dose of TDF or change to TAF. Therefore, the main objective of this study is to study patients with hepatitis B who have taken TDF and have renal function impairment that have been adjusted. Taking the same medicine with dose adjustment or changing the drug to TAF which treatment will more improve the kidney function.