Clinical data | |
---|---|
Pronunciation | /ˌraɪbəˈvaɪrɪn/ RY-bə-VY-rin |
Trade names | Copegus, Rebetol, Virazole, other [1] |
Other names | 1-(β-D-Ribofuranosyl)-1"H"-1,2,4-triazole-3-carboxamide, tribavirin (BAN UK) |
AHFS/Drugs.com | Monograph |
MedlinePlus | a605018 |
License data | |
Pregnancy category |
|
Routes of administration | Oral, Inhalation |
ATC code | |
Legal status | |
Legal status | |
Pharmacokinetic data | |
Bioavailability | 64% [5] |
Protein binding | 0% [5] |
Metabolism | liver and intracellularly [5] |
Elimination half-life | 298 hours (multiple dose); 43.6 hours (single dose) [5] |
Excretion | Urine (61%), faeces (12%) [5] |
Identifiers | |
| |
CAS Number | |
PubChem CID | |
IUPHAR/BPS | |
DrugBank | |
ChemSpider | |
UNII | |
KEGG | |
ChEMBL | |
NIAID ChemDB | |
PDB ligand | |
CompTox Dashboard (EPA) | |
ECHA InfoCard | 100.164.587 |
Chemical and physical data | |
Formula | C8H12N4O5 |
Molar mass | 244.207 g·mol−1 |
3D model (JSmol) | |
Melting point | 166 to 168 °C (331 to 334 °F) |
| |
| |
(verify) |
Ribavirin, also known as tribavirin, is an antiviral medication used to treat RSV infection, hepatitis C and some viral hemorrhagic fevers. [1] For hepatitis C, it is used in combination with other medications such as simeprevir, sofosbuvir, peginterferon alfa-2b or peginterferon alfa-2a. [1] Among the viral hemorrhagic fevers it is sometimes used for Lassa fever, Crimean–Congo hemorrhagic fever, and Hantavirus infection but should not be used for Ebola or Marburg infections. [1] Ribavirin is taken orally (swallowed by mouth) or inhaled. [1] Despite widespread usage, since the 2010s it has faced scrutiny for a lack of efficacy in treating viral infections it has historically been prescribed for. [6] [7]
Common side effects include tiredness, headache, nausea, fever, muscle pains, and an irritable mood. [1] Serious side effects include red blood cell breakdown, liver problems, and allergic reactions. [1] Use during pregnancy results in harm to the baby. [1] Effective birth control is recommended for both males and females for at least seven months during and after use. [8] The mechanism of action of ribavirin is not entirely clear. [1]
Ribavirin was patented in 1971 and approved for medical use in 1986. [9] It is on the World Health Organization's List of Essential Medicines. [10] It is available as a generic medication. [1]
Ribavirin is used primarily to treat chronic hepatitis C and viral hemorrhagic fevers (which is an orphan indication in most countries). [11] Its efficacy for these purposes has been questioned: it has an FDA boxed warning against its use as a monotherapy (sole drug) for chronic hepatitis C, and thus it may only be prescribed in the United States as an adjunct to one or more other medications. Its efficacy against other viruses, including those that cause viral hemorrhagic fever, has not been conclusively demonstrated, and it is not approved in the United States for treatment of viruses other than HCV. [7] [6]
For chronic hepatitis C, the oral (capsule or tablet) form of ribavirin is used only in combination with pegylated interferon alfa. [6] [12] [13] [14] [15] Statins may improve this combination's efficacy in treating hepatitis C. [16] When possible, genotyping of the specific viral strain is done; ribavirin is only used as a dose-escalating [lower-alpha 1] adjuvant to specific combinations of genotypes and other medications. [17]
Acute hepatitis C infection (within the first 6 months) often does not require immediate treatment, as many infections eventually resolve without treatment. [18] When the decision is made to treat acute hepatitis C, ribavirin may be used as an adjunct to several drug combinations. [17] However, other medications are preferred. [17] [18]
Ribavirin is the only known treatment for a variety of viral hemorrhagic fevers, including Lassa fever, Crimean-Congo hemorrhagic fever, Venezuelan hemorrhagic fever, and Hantavirus infection, although data regarding these infections are scarce and the drug might be effective only in early stages. [19] [20] [21] [22] It is noted by the United States Army Medical Research Institute of Infectious Diseases (USAMRIID) that "Ribavirin has poor in vitro and in vivo activity against the filoviruses (Ebola [23] and Marburg) and the flaviviruses (dengue, yellow fever, Omsk hemorrhagic fever, and Kyasanur forest disease)" [24] The aerosol form has been used in the past to treat respiratory syncytial virus-related diseases in children, although the evidence to support this is rather weak. [25]
Despite questions surrounding its efficacy, ribavirin remains the only antiviral known to be effective in treating Lassa fever. [26]
It has been used (in combination with ketamine, midazolam, and amantadine) in treatment of rabies. [27]
Experimental data indicate that ribavirin may have useful activity against canine distemper and poxviruses. [28] [29] Ribavirin has also been used as a treatment for herpes simplex virus. One small study found that ribavirin treatment reduced the severity of herpes outbreaks and promoted recovery, as compared with placebo treatment. [30] Another study found that ribavirin potentiated the antiviral effect of acyclovir. [31]
Some interest has been seen in its possible use as a treatment for cancers with elevated eukaryotic translation initiation factor eIF4E, especially acute myeloid leukemia (AML) as well as in head and neck cancers. [32] [33] [34] [35] Ribavirin targeted eIF4E in AML patients in monotherapy and combination studies and this corresponded to objective clinical responses including complete remissions. [36] [37] [38] Ribavirin resistance in AML patients arose leading to loss of eIF4E targeting and relapse. Resistance was caused by deactivation of ribavirin through its glucuronidation in AML cells or impaired drug entry/retention in the AML cells. [39] There may be additional forms of ribavirin resistance displayed by cancer cells. In HPV related oropharyngeal cancers, ribavirin reduced levels of phosphorylated form of eIF4E in some patients. [35] The best response here was stable disease but another head and neck study had more promising results. [34]
The medication has two FDA "black box" warnings: One raises concerns that use before or during pregnancy by either sex may result in birth defects in the baby, and the other is regarding the risk of red blood cell breakdown. [40]
Ribavirin should not be given with zidovudine because of the increased risk of anemia; [41] concurrent use with didanosine should likewise be avoided because of an increased risk of mitochondrial toxicity. [42]
It is a guanosine (ribonucleic) analog used to stop viral RNA synthesis and viral mRNA capping, thus, it is a nucleoside analog. Ribavirin is a prodrug, which when metabolized resembles purine RNA nucleotides. In this form, it interferes with RNA metabolism required for viral replication. Over five direct and indirect mechanisms have been proposed for its mechanism of action. [43] The enzyme inosine triphosphate pyrophosphatase (ITPase) dephosphorylates ribavirin triphosphate in vitro to ribavirin monophosphate, and ITPase reduced enzymatic activity present in 30% of humans potentiates mutagenesis in hepatitis C virus. [44]
Ribavirin's amide group can make the native nucleoside drug resemble adenosine or guanosine, depending on its rotation. For this reason, when ribavirin is incorporated into RNA, as a base analog of either adenine or guanine, it pairs equally well with either uracil or cytosine, inducing mutations in RNA-dependent replication in RNA viruses. Such hypermutation can be lethal to RNA viruses. [45] [46]
Neither of these mechanisms explains ribavirin's effect on many DNA viruses, which is more of a mystery, especially given the complete inactivity of ribavirin's 2' deoxyribose analogue, which suggests that the drug functions only as an RNA nucleoside mimic, and never a DNA nucleoside mimic. Ribavirin 5'-monophosphate inhibits cellular inosine monophosphate dehydrogenase, thereby depleting intracellular pools of GTP. [47] [ failed verification ]
This article needs more reliable medical references for verification or relies too heavily on primary sources , specifically: eIF4E targeting in cancer.(April 2023) |
The eukaryotic translation initiation factor eIF4E plays multiple roles in RNA metabolism with translation being the best described. Biophysical and NMR studies first revealed that ribavirin directly bound the eIF4E, providing another mechanism for its action. [48] [49] [50] [39] 3H Ribavirin also interacts with eIF4E in cells. [39] [33] While inosine monophosphate dehydrogenase (IMPDH) presumably only binds the ribavirin monophosphate metabolite (RMP), eIF4E can bind ribavirin and with higher affinity ribavirin's phosphorylated forms. [48] [49] [33] In many cell lines, studies into steady state levels of metabolites indicate that ribavirin triphosphate (RTP) is more abundant than the RMP metabolite which is the IMPDH ligand. [51] [52] RTP binds to eIF4E in its cap-binding site as observed by NMR. [50] Ribavirin inhibits eIF4E activities in cells including in its RNA export, translation and oncogenic activities lines. [48] [49] [53] [54] [39] [55] [56] [57] [58] [59] [60] [61] [62] In AML patients treated with ribavirin, ribavirin blocked the nuclear import of eIF4E through interfering with its interaction with its nuclear importer, Importin 8, thereby impairing its nuclear activities. [63] [38] [37] [39] Clinical relapse in AML patients corresponded to loss of ribavirin binding leading to nuclear re-entry of eIF4E and re-emergence of its nuclear activities. [63] [38] [37] [39]
Ribavirin was first made in 1972 under the national cancer institute's Virus-Cancer program. [64] This was done by researchers from International Chemical and Nuclear Corporation including Roberts A. Smith, Joseph T. Witkovski and Roland K. Robins. [65] It was reported that ribavirin was active against a variety of RNA and DNA viruses in culture and in animals, without undue toxicity in the context of cancer chemotherapies. [66] By the late 1970s, the Virus-Cancer program was widely considered a failure, and the drug development was abandoned.[ citation needed ]
After the US Government announced that AIDS was caused by a retrovirus in 1984, drugs examined during the Virus-Cancer program and its focus on retroviruses were re-examined. Although the FDA first approved ribavirin as an antiviral in 1986, it was not indicated to treat HIV or AIDS. As a result, many people with AIDS sought to obtain black market ribavirin via buyer's clubs. The drug was approved for investigational use against hantavirus in the United States in 1993, but the results from a non-randomized uncontrolled trial were not encouraging: 71% of recipients became anemic and 47% died.
In 2002 with the SARS outbreak, early speculation focused on Ribavirin as a possible anti-SARS agent. [67] Early protocols adopted in Hong Kong adopted a "Hit Hard Hit Early" approach treating SARS with high doses of off-label steroids and Ribavirin. [68] Unfortunately, it later turned out this haphazard approach was at best ineffective and at worst fatal, with many deaths attributed to SARS caused by ribavirin toxicity. [69]
Ribavirin is the INN and USAN, whereas tribavirin is the BAN. Brand names of generic forms include Copegus, Ribasphere, Rebetol. [1]
Ribavirin is possibly best viewed as a ribosyl purine analogue with an incomplete purine 6-membered ring. This structural resemblance historically prompted replacement of the 2' nitrogen of the triazole with a carbon (which becomes the 5' carbon in an imidazole), in an attempt to partly "fill out" the second ring--- but to no great effect. Such 5' imidazole riboside derivatives show antiviral activity with 5' hydrogen or halide, but the larger the substituent, the smaller the activity, and all proved less active than ribavirin. [70] Note that two natural products were already known with this imidazole riboside structure: substitution at the 5' carbon with OH results in pyrazofurin, an antibiotic with antiviral properties but unacceptable toxicity, and replacement with an amino group results in the natural purine synthetic precursor 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR), which has only modest antiviral properties.[ citation needed ]
The most successful ribavirin derivative to date is the 3-carboxamidine derivative of the parent 3-carboxamide, first reported in 1973 by J. T. Witkowski et al., [71] and now called taribavirin (former names "viramidine" and "ribamidine"). This drug shows a similar spectrum of antiviral activity to ribavirin, which is not surprising as it is now known to be a pro-drug for ribavirin. Taribavirin, however, has useful properties of less erythrocyte-trapping and better liver-targeting than ribavirin. The first property is due to taribavirin's basic amidine group which inhibits drug entry into RBCs, and the second property is probably due to increased concentration of the enzymes which convert amidine to amide in liver tissue. [72] Taribavirin completed phase III human trials in 2012. [73]
Interferons are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses.
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.
Viral hepatitis is liver inflammation due to a viral infection. It may present in acute form as a recent infection with relatively rapid onset, or in chronic form, typically progressing from a long-lasting asymptomatic condition up to a decompensated hepatic disease and hepatocellular carcinoma (HCC).
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.
Taribavirin is an antiviral drug in Phase III human trials, but not yet approved for pharmaceutical use. It is a prodrug of ribavirin, active against a number of DNA and RNA viruses. Taribavirin has better liver-targeting than ribavirin, and has a shorter life in the body due to less penetration and storage in red blood cells. It is expected eventually to be the drug of choice for viral hepatitis syndromes in which ribavirin is active. These include hepatitis C and perhaps also hepatitis B and yellow fever.
Umifenovir, sold under the brand name Arbidol, is an antiviral medication for the treatment of influenza and COVID infections used in Russia and China. The drug is manufactured by Pharmstandard. It is not approved by the U.S. Food and Drug Administration (FDA) for the treatment or prevention of influenza.
Pegylated interferon alfa-2b is a drug used to treat melanoma, as an adjuvant therapy to surgery. Also used to treat hepatitis C, it is no longer recommended due to poor efficacy and adverse side-effects. Subcutaneous injection is the preferred delivery method.
Eukaryotic translation initiation factor 4E, also known as eIF4E, is a protein that in humans is encoded by the EIF4E gene.
miR-122 is a miRNA that is conserved among vertebrate species. miR-122 is not present in invertebrates, and no close paralogs of miR-122 have been detected. miR-122 is highly expressed in the liver, where it has been implicated as a regulator of fatty-acid metabolism in mouse studies. Reduced miR-122 levels are associated with hepatocellular carcinoma. miR-122 also plays an important positive role in the regulation of hepatitis C virus replication.
Interferon lambda 3 encodes the IFNL3 protein. IFNL3 was formerly named IL28B, but the Human Genome Organization Gene Nomenclature Committee renamed this gene in 2013 while assigning a name to the then newly discovered IFNL4 gene. Together with IFNL1 and IFNL2, these genes lie in a cluster on chromosomal region 19q13. IFNL3 shares ~96% amino-acid identity with IFNL2, ~80% identity with IFNL1 and ~30% identity with IFNL4.
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.
Galidesivir is an antiviral drug, an adenosine analog. It was developed by BioCryst Pharmaceuticals with funding from NIAID, originally intended as a treatment for hepatitis C, but subsequently developed as a potential treatment for deadly filovirus infections such as Ebola virus disease and Marburg virus disease, as well as Zika virus. Currently, galidesivir is under phase 1 human trial in Brazil for coronavirus.
FGI-106 is a broad-spectrum antiviral drug developed as a potential treatment for enveloped RNA viruses, in particular viral hemorrhagic fevers from the bunyavirus, flavivirus and filovirus families. It acts as an inhibitor which blocks viral entry into host cells. In animal tests FGI-106 shows both prophylactic and curative action against a range of deadly viruses for which few existing treatments are available, including the bunyaviruses hantavirus, Rift Valley fever virus and Crimean-Congo hemorrhagic fever virus, the flavivirus dengue virus, and the filoviruses Ebola virus and Marburg virus.
Beclabuvir is an antiviral drug for the treatment of hepatitis C virus (HCV) infection that has been studied in clinical trials. In February 2017, Bristol-Myers Squibb began sponsoring a post-marketing trial of beclabuvir, in combination with asunaprevir and daclatasvir, to study the combination's safety profile with regard to liver function. From February 2014 to November 2016, a phase II clinical trial was conducted on the combination of asunaprevir/daclatasvir/beclabuvir on patients infected with both HIV and HCV. Furthermore, a recent meta-analysis of six published six clinical trials showed high response rates in HCV genotype 1-infected patients treated with daclatasvir, asunaprevir, and beclabuvir irrespective of ribavirin use, prior interferon-based therapy, or restriction on noncirrhotic patients, IL28B genotype, or baseline resistance-associated variants
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.
Celgosivir, in development by Migenix for the treatment of hepatitis C virus (HCV) infection, is an oral prodrug of the natural product castanospermine that inhibits alpha-glucosidase I, an enzyme that plays a critical role in viral maturation by initiating the processing of the N-linked oligosaccharides of viral envelope glycoproteins. Celgosivir is well absorbed in vitro and in vivo, and is rapidly converted to castanospermine. Celgosivir has a novel mechanism of action, and demonstrates broad antiviral activity in vitro.
NITD008 is an antiviral drug classified as an adenosine analog. It was developed as a potential treatment for flavivirus infections and shows broad spectrum antiviral activity against many related viruses such as dengue virus, West Nile virus, yellow fever virus, Powassan virus, hepatitis C virus, Kyasanur Forest disease virus, Omsk hemorrhagic fever virus, and Zika virus. However, NITD008 proved too toxic in pre-clinical animal testing to be suitable for human trials, but it continues to be used in research to find improved treatments for emerging viral diseases.
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.
Merimepodib (VX-497) is a drug which acts as an inhibitor of the enzyme inosine monophosphate dehydrogenase, which is required for the synthesis of nucleotide bases containing guanine. This consequently inhibits synthesis of DNA and RNA, and results in antiviral and immunosuppressive effects. It progressed as far as Phase 2b human clinical trials against Hepatitis C but showed only modest benefits in comparison to existing treatments, however it continues to be researched, and also shows activity against other viral diseases such as Zika virus and foot and mouth disease virus.
Katherine Borden PhD FRSC is a Canadian researcher of Molecular Biology and Biochemistry at the University of Montreal in Quebec, Canada. She has worked on finding new cancer treatments using pre-existing drugs,. She uses a combination of biochemistry, structural biology, cell biological, and clinical studies to study RNA processing. Her work provided a series of transformative revelations into the role of dysregulated RNA metabolism in cancer using the eukaryotic translation initiation factor eIF4E as an exemplar. Her studies demonstrated that dysregulation of this factor influenced multiple steps in RNA processing of thousands of RNAs simultaneously thereby reprogramming the cell to become more oncogenic. eIF4E impacts the extent of m7G RNA capping, splicing, export and/or translation of these RNAs based on the presence of cis-acting elements within the RNAs as well as induction of wide scale changes to the production of factors substantially modulated the RNA processing landscape within cells. Her work showed that modulating of many of these factors influence cell survival and cell motility contributing to cancer. Her studies also led to the finding that a substantial number of Acute Myeloid Leukemia (AML) patients were characterized by elevated eIF4E. This coupled to the discovery that eiF4E could bind to and be inhibited by an antiviral drug ribavirin led to the first clinical trials targeting eIF4E in patients. Indeed, these were also the first studies to target RNA translation or RNA export in humans. Targeting of eIF4E was safe and corresponded to objective clinical responses including remissions in patients. These studies also led to the discovery of a new form of drug resistance in patients, inducible drug glucuronidation. Drug glucuronidation impacts 50% of drugs usually through liver mediated drug deactivation. However, this work revealed that cancer cells could turn on the enzymes involved in this process. Her lab developed the means to target this inducible drug glucuronidation, with Vismodegib, and showed in patients this reduced levels of glucuronidation enzymes which corresponded to ribavirin activity, targeting of eIF4E and objective clinical responses. However, eventually patients become resistant to the Visomdegib and thus, new modalities are required to overcome this form of drug resistance long term. She has received many awards for this work including selected as a Stohlman Scholar of the Leukemia and Lymphoma Society USA (2005), Distinguished Scientist of the Canadian Society for Clinical Investigation (2011), CSMB Canadian Science Publishing Senior Investigator Award (2022) and was inducted as a fellow of the Royal Society of Canada in 2022.
Author died before publication