narlaprevir + ritonavir + sofosbuvir

Narlaprevir + ritonavir + sofosbuvir is a triple all-oral combination therapy used in clinical trials for chronic hepatitis C virus (HCV) genotype 1 infection. - **Narlaprevir** is a direct-acting antiviral that inhibits the HCV nonstructural protein 3 serine protease (NS3), disrupting viral polyprotein processing and replication. It is metabolized mainly by CYP3A4, and co-administration with ritonavir boosts its plasma concentration through CYP3A4 inhibition[3][1]. - **Ritonavir** acts as a pharmacokinetic enhancer, increasing narlaprevir levels by inhibiting CYP3A4, but is not itself active against HCV. - **Sofosbuvir** is a nucleotide analog inhibitor of the HCV NS5B RNA-dependent RNA polymerase, critical for viral replication[1]. This regimen is investigated specifically for treatment-naïve patients with HCV genotype 1, aiming for high rates of sustained virologic response (SVR) with a shorter all-oral regimen[1][7].