Used in research as a potent antiviral agent, particularly showing activity against RNA viruses. It functions as a nucleoside analog, interfering with viral RNA replication by incorporating into the growing RNA chain, causing premature termination or error catastrophe. Demonstrates promising results in preclinical studies for treating coronaviruses, including SARS-CoV-2, due to its ability to inhibit the viral RNA-dependent RNA polymerase. Also investigated for broad-spectrum antiviral applications, including respiratory syncytial virus (RSV) and other emerging RNA viruses. Its structure allows efficient cellular uptake and metabolic activation, enhancing its efficacy in infected cells. Currently under evaluation in clinical trials for antiviral therapies.