Hepatitis C is an infectious disease caused by the hepatitis C virus (HCV) that primarily affects the liver; it is a type of viral hepatitis. During the initial infection period, people often have mild or no symptoms. Early symptoms can include fever, dark urine, abdominal pain, and yellow tinged skin. The virus persists in the liver, becoming chronic, in about 70% of those initially infected. Early on, chronic infection typically has no symptoms. Over many years however, it often leads to liver disease and occasionally cirrhosis. In some cases, those with cirrhosis will develop serious complications such as liver failure, liver cancer, or dilated blood vessels in the esophagus and stomach.
The hepatitis C virus (HCV) is a small, enveloped, positive-sense single-stranded RNA virus of the family Flaviviridae. The hepatitis C virus is the cause of hepatitis C and some cancers such as liver cancer and lymphomas in humans.
Boceprevir is a protease inhibitor used to treat hepatitis caused by hepatitis C virus (HCV) genotype 1. It binds to the HCV nonstructural protein 3 active site.
Telaprevir (VX-950), marketed under the brand names Incivek and Incivo, is a pharmaceutical drug for the treatment of hepatitis C co-developed by Vertex Pharmaceuticals and Johnson & Johnson. It is a member of a class of antiviral drugs known as protease inhibitors. Specifically, telaprevir inhibits the hepatitis C viral enzyme NS3/4A serine protease. Telaprevir is only indicated for use against hepatitis C genotype 1 viral infections and has not been proven to be safe or effective when used for other genotypes of the virus. The standard therapy of pegylated interferon and ribavirin is less effective than telaprevir in those with genotype 1.
Sofosbuvir, sold under the brand name Sovaldi among others, is a medication used to treat hepatitis C. It is taken by mouth.
Asunaprevir is an experimental drug candidate for the treatment of hepatitis C. It was undergoing development by Bristol-Myers Squibb and has completed Phase III clinical trials in 2013.
Daclatasvir, sold under the brand name Daklinza, is an antiviral medication used in combination with other medications to treat hepatitis C (HCV). The other medications used in combination include sofosbuvir, ribavirin, and interferon, vary depending on the virus type and whether the person has cirrhosis. It is taken by mouth.
Simeprevir, sold under the brand name Olysio among others, is a medication used in combination with other medications for the treatment of hepatitis C. It is specifically used for hepatitis C genotype 1 and 4. Medications it is used with include sofosbuvir or ribavirin and peginterferon-alfa. Cure rates are in 80s to 90s percent. It may be used in those who also have HIV/AIDS. It is taken by mouth once daily for typically 12 weeks.
Ledipasvir is a drug for the treatment of hepatitis C that was developed by Gilead Sciences. After completing Phase III clinical trials, on February 10, 2014, Gilead filed for U.S. approval of a ledipasvir/sofosbuvir fixed-dose combination tablet for genotype 1 hepatitis C. The ledipasvir/sofosbuvir combination is a direct-acting antiviral agent that interferes with HCV replication and can be used to treat patients with genotypes 1a or 1b without PEG-interferon or ribavirin.
Faldaprevir was an experimental drug for the treatment of hepatitis C (HCV). It was being developed by Boehringer-Ingelheim and reached Phase III clinical trials in 2011. Boehringer announced in 2014 that it would not pursue approval of the drug any more because of better HCV treatments having become available.
Nonstructural protein 5B (NS5B) is a viral protein found in the hepatitis C virus (HCV). It is an RNA-dependent RNA polymerase, having the key function of replicating HCV's viral RNA by using the viral positive RNA strand as a template to catalyze the polymerization of ribonucleoside triphosphates (rNTP) during RNA replication. Several crystal structures of NS5B polymerase in several crystalline forms have been determined based on the same consensus sequence BK. The structure can be represented by a right hand shape with fingers, palm, and thumb. The encircled active site, unique to NS5B, is contained within the palm structure of the protein. Recent studies on NS5B protein genotype 1b strain J4's (HC-J4) structure indicate a presence of an active site where possible control of nucleotide binding occurs and initiation of de-novo RNA synthesis. De-novo adds necessary primers for initiation of RNA replication.
Ombitasvir is an antiviral drug for the treatment of hepatitis C virus (HCV) infection by AbbVie. In the United States, it is approved by the Food and Drug Administration for use in combination with paritaprevir, ritonavir and dasabuvir in the product Viekira Pak for the treatment of HCV genotype 1, and with paritaprevir and ritonavir in the product Technivie for the treatment of HCV genotype 4.
Elbasvir/grazoprevir, sold under the brand name Zepatier, is a fixed-dose combination for the treatment of hepatitis C, containing elbasvir and grazoprevir. It is used to treat chronic hepatitis C virus (HCV) genotypes 1 or 4 infection in both treatment-naïve and treatment-experienced patients.
Daclatasvir/sofosbuvir is a two-drug combination for the treatment of hepatitis C. It is given as a single daily pill containing daclatasvir, a viral NS5A inhibitor, and sofosbuvir, a nucleotide inhibitor of the viral RNA polymerase NS5B.
Nonstructural protein 5A (NS5A) inhibitors are direct acting antiviral agents (DAAs) that target viral proteins, and their development was a culmination of increased understanding of the viral life cycle combined with advances in drug discovery technology. However, their mechanism of action is complex and not fully understood. NS5A inhibitors were the focus of much attention when they emerged as a part of the first curative treatment for hepatitis C virus (HCV) infections in 2014. Favorable characteristics have been introduced through varied structural changes, and structural similarities between NS5A inhibitors that are clinically approved are readily apparent. Despite the recent introduction of numerous new antiviral drugs, resistance is still a concern and these inhibitors are therefore always used in combination with other drugs.
Mericitabine (RG-7128) is an antiviral drug, a deoxycytidine analog. It was developed as a treatment for hepatitis C, acting as a NS5B RNA polymerase inhibitor, but while it showed a good safety profile in clinical trials, it was not sufficiently effective to be used as a stand-alone agent. However mericitabine has been shown to boost the efficacy of other antiviral drugs when used alongside them, and as most modern treatment regimens for hepatitis C use a combination therapy of several antiviral drugs, clinical trials have continued to see if it can form a part of a clinically useful drug treatment program.
Narlaprevir, is an inhibitor of NS3/4A serine protease, intended for the treatment of chronic hepatitis C caused by genotype 1 virus in combination with other antiviral drugs.
Sofosbuvir/velpatasvir, sold under the brand name Epclusa among others, is a fixed-dose combination medication for the treatment of hepatitis C in adults. It combines sofosbuvir and velpatasvir. It is more than 90% effective for hepatitis C genotypes one through six. It also works for hepatitis C in those who also have cirrhosis or HIV/AIDS. It is taken by mouth.
Interferon lambda 4 is one of the most recently discovered human genes and the newest addition to the interferon lambda protein family. This gene encodes the IFNL4 protein, which is involved in immune response to viral infection.
TMC-647055 is an experimental antiviral drug which was developed as a treatment for hepatitis C, and is in clinical trials as a combination treatment with ribavirin and simeprevir. It acts as a NS5b polymerase inhibitor.
