ombitasvir + paritaprevir + ritonavir + dasabuvir + sofosbuvir

This is an oral **combination antiviral therapy** containing five direct-acting antiviral agents: *ombitasvir* (NS5A inhibitor), *paritaprevir* (NS3/4A protease inhibitor), *ritonavir* (CYP3A inhibitor/booster for paritaprevir), *dasabuvir* (non-nucleoside NS5B polymerase inhibitor), and *sofosbuvir* (nucleotide NS5B polymerase inhibitor). The combination acts through **multiple mechanisms to disrupt hepatitis C virus (HCV) replication**, targeting several key viral proteins required for HCV lifecycle. While the fixed-dose combination of ombitasvir, paritaprevir, ritonavir, and dasabuvir has previously been approved and marketed as "Viekira Pak", there is currently **no single branded product containing all five agents together with sofosbuvir**; co-administration would represent an off-label or investigational regimen for chronic HCV infection, aiming at potentially improved efficacy or viral resistance management.