EIDD-2801 is primarily investigated for its antiviral properties, particularly in the treatment of RNA virus infections. It functions as a ribonucleoside analog that induces lethal mutagenesis in viral genomes, effectively inhibiting viral replication. The compound has shown promising activity against a range of viruses, including influenza, respiratory syncytial virus (RSV), and coronaviruses such as SARS-CoV-2. Due to its broad-spectrum antiviral effect, it is being explored as an oral therapeutic option for early-stage treatment of viral infections, especially in outpatient settings. Its ability to be administered orally enhances its potential for widespread use during outbreaks. Research also supports its efficacy in reducing viral load and mitigating disease progression in preclinical models.