Velpatasvir (VEL; GS-5816) is an inhibitor of HCV NS5A protein, it demonstrated favourable in vitro and in vivo properties, including potent antiviral activity against hepatitis C virus genotypes 1 to 6 replicon, good metabolic stability, low systemic clearance, and adequate bioavailability and physicochemical properties to warrant clinical evaluation. Velpatasvir is used together with sofosbuvir in the treatment of hepatitis C infection of all six major genotypes. A once-daily, single-tablet, pangenotypic regimen comprising the HCV NS5B polymerase inhibitor sofosbuvir and the HCV NS5A inhibitor velpatasvir (sofosbuvir/ velpatasvir; Epclusa) has recently been approved for the treatment of adults with chronic HCV genotype 1, 2, 3, 4, 5 or 6 infection in the USA, EU and Canada.

Grazoprevir is a second generation NS3/4A protease inhibitor approved in the EU and the USA for the treatment of hepatitis C virus (HCV) genotypes 1 and 4 infections in adult patients in combination with elbasvir (C virus (HCV) NS5A inhibitor) as the fixed-dose combination product Zepatier with or without ribavirin. In phase III trials, 12 or 16 weeks of treatment with once-daily elbasvir/grazoprevir (fixed-dose tablet or as individual agents), taken with or without ribavirin, generally provided high rates of sustained virological response at 12 weeks (SVR12) in treatment-naive and -experienced adult patients with chronic HCV genotype 1a, 1b or 4 infection, including those with or without compensated cirrhosis, HIV co-infection, inherited blood disorders or chronic kidney disease or patients receiving opioid agonist therapy or of Japanese origin. Elbasvir/grazoprevir was generally well tolerated. Thus, elbasvir/grazoprevir, with or without ribavirin, represents an effective new option for the treatment of adults with chronic HCV genotype 1 and 4 infection, including a number of difficult-to-treat populations.

Dabrafenib is a selective, orally bioavailable inhibitor of Mutant BRAF protein kinase with potential antineoplastic activity. Dabrafenib inhibits BRAF kinases with in vitro IC50 values of 0.65, 0.5, and 1.84 nM for BRAF V600E, BRAF V600K, and BRAF V600D enzymes, respectively. Dabrafenib also inhibits wild-type BRAF and CRAF kinases with IC50 values of 3.2 and 5.0 nM. BRAF belongs to the the raf/mil family of serine/threonine protein kinases and plays a role in regulating the MAP kinase/ERKs signaling pathway, which may be constitutively activated due to BRAF gene mutations. Mutations in BRAF are associated with increased growth and proliferation of cancer cells. By inhibiting BRAF kinase dabrafenib negatively regulates the proliferation of tumor cells which contain a mutated BRAF gene. Dabrafenib (in combination with trametinib or alone) is indicated for the treatment of unresectable or metastatic melanoma with BRAF V600E mutation

Eltrombopag is a thrombopoietin (TPO) nonpeptide mimetic administered orally that activates the TPO receptor by binding to the transmembrane domain and initiates signaling cascades that induce proliferation and differentiation of megakaryocytes from bone marrow progenitor cells. Eltrombopag under brand name promacta is approved for the treatment of the low blood platelet counts in adults with chronic immune (idiopathic) thrombocytopenia (ITP), when certain other medicines, or surgery to remove the spleen, have not worked well enough. ITP is a condition that may cause unusual bruising or bleeding due to an abnormally low number of platelets in the blood. Eltrombopag has also been approved for the treatment of thrombocytopenia (low blood platelet counts) in patients with chronic hepatitis C to allow them to initiate and maintain interferon-based therapy and to treat patients with severe aplastic anemia who have had an insufficient response to immunosuppressive therapy.

Atazanavir is the first once-daily protease inhibitor for the treatment of human immunodeficiency virus type 1 infection and should be used only in combination therapy, as part of a highly active antiretroviral therapy (HAART) regimen. In addition to being the most potent protease inhibitor in vitro, atazanavir has a distinct cross-resistance profile that does not confer resistance to other protease inhibitors. However, resistance to other protease inhibitors often confers clinically relevant resistance to atazanavir.

Ombitasvir (ABT-267) is an antiviral drug for the treatment of hepatitis C virus (HCV) infection. Ombitasvir is a potent inhibitor of the hepatitis C virus protein NS5A, has favorable pharmacokinetic characteristics and is active in the picomolar range against genotype 1 - 6. In 2015, it was approved by FDA for use in combination with paritaprevir, ritonavir and dasabuvir in the product Viekira Pak for the treatment of HCV genotype 1.

Daclatasvir (BMS-790052) is a direct-acting antiviral agent against Hepatitis C Virus (HCV) used for the treatment of chronic HCV genotype 3 infection. Daclatasvir prevents RNA replication and virion assembly by binding to NS5A, a nonstructural phosphoprotein encoded by HCV. Binding to the N-terminus of the D1 domain of NS5A prevents its interaction with host cell proteins and membranes required for virion replication complex assembly.

Dasabuvir is a non-nucleoside inhibitor of the hepatitis C virus (HCV) NS5B palm polymerase inhibitor. It is used in the treatment of adult patients with chronic hepatitis C virus infection in combination with ombitasvir, paritaprevir, and ritonavir as the combination product Viekira Pak. Viekira PAK combines three direct-acting antiviral agents with distinct mechanisms of action and non-overlapping resistance profiles to target HCV at multiple steps in the viral lifecycle. Dasabuvir is extensively evaluated in large clinical trials and shown excellent sustained virological response among hepatitis C virus genotype1 patient population in combination with other oral direct acting antivirals, with good safety profile and tolerance.

Simeprevir is a hepatitis C virus (HCV) NS3/4A protease inhibitor approved for the treatment of Chronic Hepatitis C (genotype 1 and 4). Inhibiting NS3/4A, simeprevir blocks viral replication. In in vitro assays simeprevir was potent against HCV genotype 1a and 1b. Simeprevir must not be administered as monotherapy and should only be prescribed with both peginterferon alfa and ribavirin.

Paritaprevir is a potent inhibitor of the NS3/4A protease that rapidly and consistently suppresses HCV. Paritaprevir is metabolized by the Cytochrome P450 isoform 3A (CYP3A); therefore, ritonavir was used concurrently to increase plasma concentrations and to prolong the half-life of this agent allowing for once-daily dosing. Several antiviral regimens combining paritaprevir with other agents have shown impressive results, tolerable side effects, and importantly, provided support of ‘all-oral’ interferon-free regimens against HCV. Paritaprevir monotherapy is discontinued now but paritaprevir is used as a component of Viekira Pak and Technivie for the treatment of patients with genotype 1 chronic hepatitis C virus (HCV) infection.