Ribavirin, also known as tribavirin, is an antiviral medication used to treat RSV infection, hepatitis C and some viral hemorrhagic fevers. For hepatitis C, it is used in combination with other medications such as simeprevir, sofosbuvir, peginterferon alfa-2b or peginterferon alfa-2a. Among the viral hemorrhagic fevers it is used for Lassa fever, Crimean–Congo hemorrhagic fever, and Hantavirus infection but should not be used for Ebola or Marburg infections. Ribavirin is taken by mouth or inhaled.
Thymidine kinase is an enzyme, a phosphotransferase : 2'-deoxythymidine kinase, ATP-thymidine 5'-phosphotransferase, EC 2.7.1.21. It can be found in most living cells. It is present in two forms in mammalian cells, TK1 and TK2. Certain viruses also have genetic information for expression of viral thymidine kinases. Thymidine kinase catalyzes the reaction:
Vidarabine or 9-β-D-arabinofuranosyladenine (ara-A) is an antiviral drug which is active against herpes simplex and varicella zoster viruses.
Brivudine is an antiviral drug used in the treatment of herpes zoster ("shingles"). Like other antivirals, it acts by inhibiting replication of the target virus.
Tiazofurin is a drug which acts as an inhibitor of the enzyme IMP dehydrogenase. Tiazofurin and its analogues were under investigation for potential use in the treatment of cancer, though side effects such as pleuropericarditis and a flu-like syndrome precluded further development. They also show antiviral effects and may be reevaluated as potential options in the treatment of newly emerging viral diseases.
The Dacrymycetes are a class of fungi in the Basidiomycota. The class currently contains the single order Dacrymycetales, with a second proposed order Unilacrymales now treated at the family level. The order contains four families and has a cosmopolitan distribution.
Discovery and development of nucleoside and nucleotide reverse-transcriptase inhibitors began in the 1980s when the AIDS epidemic hit Western societies. NRTIs inhibit the reverse transcriptase (RT), an enzyme that controls the replication of the genetic material of the human immunodeficiency virus (HIV). The first NRTI was zidovudine, approved by the U.S. Food and Drug Administration (FDA) in 1987, which was the first step towards treatment of HIV. Six NRTI agents and one NtRTI have followed. The NRTIs and the NtRTI are analogues of endogenous 2´-deoxy-nucleoside and nucleotide. Drug-resistant viruses are an inevitable consequence of prolonged exposure of HIV-1 to anti-HIV drugs.
Rocaglamide is a natural product which belongs to a class of molecules called flavaglines. This compound was isolated in 1982 by King, Ming-Lu (金明儒) and colleagues based on its antileukemic activity. The name of Rocaglamide is named from two parts: Roc- and aglamide. Roc- means Republic of China(中華民國), the place in which this product isolated; aglamide indicates this product is isolated from Large-leaved Aglaia. Like other flavaglines, rocaglamide displays potent insecticidal, antifungal, anti-inflammatory and anticancer activities. Rocaglamide A (RocA) inhibits eukaryotic translation initiation by binding to the translation initiation factor eIF4A and converting it into a translational repressor.
PMEG is an acyclic nucleoside phosphonate. Acyclic nucleoside phosphonates can have significant antiviral, cytostatic and antiproliferative activities. PMEG can inhibit cell proliferation and cause genotoxicity. PMEG is active against leukemia and melanoma in animal tumor models, and also has antiviral activities against herpes viruses in murine models.
Homoisoflavonoids (3-benzylidenechroman-4-ones) are a type of phenolic compounds occurring naturally in plants.
The ProTide technology is a prodrug approach used in molecular biology and drug design. It is designed to deliver nucleotide analogues into the cell. It was invented by Professor Chris McGuigan in the early 1990s. They form a critical part of the anti-viral drugs: sofosbuvir, tenofovir alafenamide and remdesivir.
Carbocyclic nucleosides are nucleoside analogues in which a methylene group has replaced the oxygen atom of the furanose ring. These analogues have the nucleobase attached at a simple alkyl carbon rather than being part of a hemiaminal ether linkage. As a result, they have increased chemical stability. They also have increased metabolic stability because they are unaffected by phosphorylases and hydrolases that cleave the glycosidic bond between the nucleobase and furanose ring of nucleosides. They retain many of the biological properties of the original nucleosides with respect to recognition by various enzymes and receptors.
MK-608 is an antiviral drug, an adenosine analog. It was originally developed by Merck & Co. as a treatment for hepatitis C, but despite promising results in animal studies, it was ultimately unsuccessful in clinical trials. Subsequently it has been widely used in antiviral research and has shown activity against a range of viruses, including Dengue fever, tick-borne encephalitis virus, poliovirus, and most recently Zika virus, in both in vitro and animal models. Since it has already failed in human clinical trials previously, it is unlikely MK-608 itself will be developed as an antiviral medication, but the continuing lack of treatment options for these emerging viral diseases means that much research continues using MK-608 and related antiviral drugs.
Non-structural protein 5B (NS5B) inhibitors are a class of direct-acting antivirals widely used in the treatment of chronic hepatitis C. Depending on site of action and chemical composition, NS5B inhibitors may be categorized into three classes—nucleoside active site inhibitors (NIs), non-nucleoside allosteric inhibitors, and pyrophosphate analogues. Subsequently, all three classes are then subclassified. All inhibit RNA synthesis by NS5B but at different stages/sites resulting in inability of viral RNA replication. Expression of direct-acting NS5B inhibitors does not take place in cells that are not infected by hepatitis C virus, which seems to be beneficial for this class of drugs.
GS-6620 is an antiviral drug which is a nucleotide analogue. It was developed for the treatment of Hepatitis C but while it showed potent antiviral effects in early testing, it could not be successfully formulated into an oral dosage form due to low and variable absorption in the intestines which made blood levels unpredictable. It has however continued to be researched as a potential treatment for other viral diseases such as Ebola virus disease.
EICAR is a drug which acts as an inhibitor of the enzyme IMP dehydrogenase. It is a nucleoside derivative which has both anti-cancer and antiviral effects, and was originally developed for the treatment of leukemia, but was unsuccessful in human clinical trials. It has broad spectrum antiviral effects with activity against pox viruses, Semliki forest virus, Junin virus, reovirus, influenza, measles virus and respiratory syncytial virus among others, although it is not active against coronaviridae such as SARS-CoV-1. This useful spectrum of activity means that EICAR and related derivatives continue to be investigated for the treatment of viral diseases.
North-Methanocarbathymidine (N-MCT) is an antiviral drug which is an analogue of thymidine, and shows activity against herpesviruses, orthopoxviruses and HIV, though it has not been introduced into clinical use.
Katherine Seley-Radtke is an American medicinal chemist who specializes in the discovery and design of novel nucleoside or nucleotide based enzyme inhibitors that may be used to treat infections or cancer. She has authored over 90 peer-reviewed publications,is an inventor of five issued US patents, and is a Professor in the Department of Chemistry & Biochemistry at the University of Maryland, Baltimore County. Her international impact includes scientific collaborations, policy advising and diplomatic appointments in biosecurity efforts.
Sangivamycin is a natural product originally isolated from Streptomyces rimosus, which is a nucleoside analogue. It acts as an inhibitor of protein kinase C. It has antibiotic, antiviral and anti-cancer properties and has been investigated for various medical applications, though never approved for clinical use itself. However, a number of related derivatives continue to be researched.
Lydicamycin is an organic compound with the molecular formula C47H74N4O10. Lydicamycin is an antibiotic with activity against Gram-positive bacteria. The bacteria Streptomyces lydicamycinicus and Streptomyces platensis produces lydicamycin.
