Ruzasvir is primarily used in the treatment of chronic hepatitis C virus (HCV) infection. It functions as an NS5A inhibitor, targeting a specific protein essential for viral replication. This makes it effective in reducing viral load and achieving sustained virologic response (SVR) when combined with other antiviral agents, such as sofosbuvir. Its application is particularly significant for patients with HCV genotypes 1, 2, 3, 4, 5, or 6, offering a potent therapeutic option for those who may not respond well to other treatments. Ruzasvir is often part of combination therapies to enhance efficacy, minimize resistance, and improve patient outcomes.