Repositioning Candidate Details

Candidate ID: R0289
Source ID: DB00811
Source Type: approved
Compound Type: small molecule
Compound Name: Ribavirin
Synonyms: 1-beta-D-Ribofuranosyl-1,2,4-triazole-3-carboxamide; 1-beta-D-Ribofuranosyl-1H-1,2,4-triazole-3-carboxamide; RBV; Tribavirin
Molecular Formula: C8H12N4O5
SMILES: NC(=O)C1=NN(C=N1)[C@@H]1O[C@H](CO)[C@@H](O)[C@H]1O
Structure:
DrugBank Description: Producing a broad-spectrum activity against several RNA and DNA viruses, Ribavirin is a synthetic guanosine nucleoside and antiviral agent that interferes with the synthesis of viral mRNA. It is primarily indicated for use in treating hepatitis C and viral hemorrhagic fevers. HCV is a single-stranded RNA virus that is categorized into nine distinct genotypes, with genotype 1 being the most common in the United States, and affecting 72% of all chronic HCV patients . It is reported that ribavirin might be only effective in early stages of viral hemorrhagic fevers including Lasser fever, Crimean-Congo hemorrhagic fever, Venezuelan hemorrhagic fever, and Hantavirus infection. Ribavirin is a prodrug that is metabolized into nucleoside analogs that blocks viral RNA synthesis and viral mRNA capping. Before the development of newer drugs, ribavirin and / dual therapy was considered the first-generation and standard antiviral treatment . The dual therapy was administered for 48 weeks in patients with genotype 1, 4, 5, and 6, and 24 weeks in patients with genotype 2 and 3 . Newer drugs developed as Hepatitis C viral infection treatments can be used to reduce or eliminate the use of ribavirin, which are associated with serious adverse effects. They also improve therapeutic efficacy in patients with failed / and ribavirin-based therapy. The potential use of ribavirin as a treatment for acute myeloid leukemia is currently under investigation. According to 2017 American Association for the Study of Liver Diseases (AASLD) and 2015 consensus guidelines from the Canadian Association for the Study of the Liver (CASL), ribavirin is typically used as an adjunct therapy to various first-line and second-line combination therapies recommended for each genotypes. Ribavirin is added to decrease relapse rates by accelerating viral clearance early in the treatment course . When used to treat Hepatitis C virus (HCV) infections, it is always used as a part of combination therapies as ribavirin monotherapy is not efficacious in the treatment of chronic hepatitis C infection . Additionally, including ribavirin in the regimen can increase the risk of anemia. In HCV genotye 1/2/3/4/5/6 patients, ribavirin can be used in combination therapy involving and , Eplusa (, ), Harvoni (, ), and , Viekira Pak (, , , ), Technivie (, , ) and Zepatier (, ). Addition of weight-based ribavirin to Technivie therapy increased sustained virologic response after 12 weeks of daily therapy (SVR12) from 90% to 97% in patients with HCV genotype 1a and 90.9% to 100% in HCV genotype 4 patients . Zepatier therapy along with ribavirin improved SVR in HCV genotype 5 patients. Combination therapy of ribavirin and results in the SVR of 44% in patients with genotype 1 infection and 70% in patients with genotype 2-6. The inclusion of ribavirin in the combination therapies depend on individual patient's profile, for example if HCV genotype 3 patient has a Y93H genetic variant and compensated cirrhosis.
CAS Number: 36791-04-5
Molecular Weight: 244.2047
DrugBank Indication: Indicated for the treatment of chronic Hepatitis C virus (HCV) infection in combination with other antiviral agents with the intent to cure or achieve a sustained virologic response (SVR). Typically added to improve SVR and reduce relapse rates . The addition of ribavirin in Technivie therapy indicated for treating HCV genotype 1a and 4 infections is recommended in patients with or without cirrhosis. Resistance: viral genetic determinants resulting in variable response to ribavirin therapy has not been yet determined.
DrugBank Pharmacology: Ribavirin mediates direct antiviral activity against a number of DNA and RNA viruses by increasing the mutation frequency in the genomes of several RNA viruses. It is a member of the nucleoside antimetabolite drugs that interfere with duplication of the viral genetic material. The drug inhibits the activity of the enzyme RNA dependent RNA polymerase, due to its resemblence to building blocks of the RNA molecules.
DrugBank MoA: Ribavirin is reported to have several mechanism of actions that lead to inhibition of viral RNA and protein synthesis. After activation by adenosine kinase to ribavirin mono-, di-, and triphosphate metabolites. Ribavirin triphosphate (RTP) is the predominant metabolite which directly inhibits viral mRNA polymerase by binding to the nucleotide binding site of the enzyme. This prevents the binding of the correct nucleotides, leading to a reduction in viral replication or to the production of defective virions . RTP also demonstrates an inhibitory action on viral mRNA guanylyltransferase and mRNA 2′-O-methyltransferase of dengue virus. Inhibition of these enzymes disrupts the posttranslational capping of the 5′ end of viral mRNA through ribavirin being incorporated at the 5′ end in place of guanosine and preventing the cap methylation step. Inhibition of host inosine monophosphate dehydrogenase (IMPDH) and subsequent depletion of GTP pool is proposed to be another mechanism of action of ribavirin. IMPDH catalyzes the rate-limiting step where inosine 5′-monophosphate is converted to xanthine monophosphate during guanosine monophosphate (GMP) synthesis. GMP is later converted to guanosine triphoshpate (GTP). Ribavirin monophosphate mimics inosine 5′-monophosphate and acts as a competitive inhibitor of IMPDH. Inhibited de novo synthesis of guanine nucleotides and decreased intracellular GTP pools leads to a decline in viral protein synthesis and limit replication of viral genomes . Ribavirin acts as a mutagen in the target virus to cause an 'error catastrophe' due to increased viral mutations. RTP pairs with cytidine triphosphate or uridine triphosphate with equal efficiency and to block HCV RNA elongation. It causes premature termination of nascent HCV RNA and increases mutagenesis by producing defective virions . Ribavirin also exerts an immunomodulatory action of the host to the virus by shifting a Th2 response in favor of a Th1 phenotype. Th2 response and production of type 2 cytokines such as IL-4, IL-5, and IL-10 stimulates the humoral response which enhances immunity toward the virus . Ribavirin enhanced induction of interferon-related genes, including the interferon-α receptor, and down-regulation of genes involved in interferon inhibition, apoptosis, and hepatic stellate cell activation in vitro .
Targets: Inosine-5'-monophosphate dehydrogenase 1 inhibitor; Inosine-5'-monophosphate dehydrogenase 2; RNA-directed RNA polymerase L antagonist; RNA-directed RNA polymerase catalytic subunit inhibitor; Genome polyprotein inhibitor
Inclusion Criteria: Therapeutic strategy associated