VIEKIRAX Film-coated tablet Ref.[108064] Active ingredients: Ombitasvir Ombitasvir, Paritaprevir and Ritonavir Paritaprevir Ritonavir

Ombitasvir is an nonstructural protein 5A (NS5A) inhibitor that acts by inhibiting the HCV protein NS5A.

Ombitasvir/paritaprevir/ritonavir, when co-administered with dasabuvir, combines three direct-acting antiviral medicinal products with distinct mechanisms of action and non-overlapping resistance profiles to target HCV at multiple steps in the viral lifecycle. Ombitasvir is an inhibitor of HCV NS5A which is essential for viral replication. Paritaprevir is an inhibitor of HCV NS3/4A protease which is necessary for the proteolytic cleavage of the HCV encoded polyprotein (into mature forms of the NS3, NS4A, NS4B, NS5A, and NS5B proteins) and is essential for viral replication. Ritonavir is not active against HCV. Ritonavir is a CYP3A inhibitor that increases the systemic exposure of the CYP3A substrate paritaprevir.

Ritonavir is an orally active peptidomimetic inhibitor of the HIV-1 and HIV-2 aspartyl proteases. Inhibition of HIV protease renders the enzyme incapable of processing the gag-pol polyprotein precursor which leads to the production of HIV particles with immature morphology that are unable to initiate new rounds of infection. Ritonavir has selective affinity for the HIV protease and has little inhibitory activity against human aspartyl proteases. Pharmacokinetic enhancement by ritonavir is based on ritonavir’s activity as a potent inhibitor of CYP3A-mediated metabolism.