Tenofovir Alafenamide Tablets 25 mg is a prodrug of tenofovir with improved delivery and safety compared to tenofovir disoproxil fumarate. After oral administration, it enters liver cells by passive diffusion and specific transporters, then converts to the active form, tenofovir diphosphate. This active metabolite inhibits hepatitis B virus (HBV) and HIV reverse transcriptase enzymes, causing premature termination of viral DNA synthesis, thereby preventing viral replication. Tenofovir alafenamide achieves higher intracellular concentrations with lower plasma levels, resulting in enhanced antiviral potency and reduced renal and bone toxicity risk compared to older formulations.