AT-527 is an investigational antiviral agent primarily studied for its potential in treating viral infections, particularly hepatitis C and SARS-CoV-2. It functions as a nucleoside inhibitor, interfering with viral RNA replication by targeting the RNA-dependent RNA polymerase enzyme. This mechanism makes it effective against a range of RNA viruses. In clinical development, AT-527 has been evaluated for oral bioavailability and potency in reducing viral load, showing promise as a once-daily treatment option. Its application is focused on outpatient settings for early-stage viral infection, aiming to prevent disease progression and hospitalization. Research continues to explore its efficacy, safety, and potential use in combination therapies.