narlaprevir + ritonavir + tenofovir disoproxil fumarate

This drug is a **combination of three oral small molecule antiviral agents** used as part of investigational therapy in patients with hepatitis C virus (HCV) and HIV coinfection. - **Narlaprevir** is an HCV NS3/4A protease inhibitor, blocking viral replication by inhibiting the viral protease necessary for polyprotein processing. - **Ritonavir** is primarily used as a pharmacokinetic enhancer (“booster”) that inhibits CYP3A-mediated metabolism, increasing exposure to coadministered protease inhibitors. - **Tenofovir disoproxil fumarate** is a nucleotide analog reverse transcriptase inhibitor (NtRTI) that blocks reverse transcriptase, inhibiting viral DNA synthesis in HIV and HBV[1][2][4]. The combination is administered orally to assess drug-drug interactions and optimize co-treatment regimens for HCV/HIV-coinfected patients[1][5].