Narlaprevir is a HCV NS3 protease inhibitor.
NS3 protease is essential for viral replication representing an important target for antiviral therapy. Since identification of NS3 protease, this chymotrypsin-like serine protease has been found to be an attractive target for HCV antiviral therapeutics.
In vitro: Narlaprevir was identified to be a novel ketoamide protease inhibitor which formed a reversible covalent bond with the active-site serine. Narlaprevir could inhibit replicon RNA at a EC90 of 40 nM. Morevoer, in biochemical assays, narlaprevir was active against proteases of genotypes 1 to 3. In addition, cross-resistance studies showed the majority of mutations for resistance to boceprevir and telaprevir caused similar fold