Ribasphere

Ribasphere Uses, Dosage, Side Effects, Food Interaction and all others data.

Ribasphere is a synthetic nucleoside which has inhibitory action against respiratory syncytial virus, influenza virus and herpes simplex virus. The mechanism of action is not clear. It may act at several sites including cellular enzymes to interfere with viral nucleic acid synthesis. The mono- and triphosphate derivatives are known to be responsible for the antiviral action of the compound.

Ribasphere 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.

Trade Name Ribasphere
Availability Prescription only
Generic Ribavirin
Ribavirin Other Names Ribavirin, Ribavirina, Ribavirine, Ribavirinum, Tribavirin
Related Drugs Epclusa, Mavyret, Harvoni, sofosbuvir / velpatasvir, Sovaldi, Synagis, Vosevi, respiratory syncytial virus immune globulin, RespiGam, palivizumab
Weight 200mg, 40mg/ml, 200mg, 200mg + 400mg, 400mg, 400mg + 600mg, 600mg
Type Tablet, Film Coated, Oral Capsule, Oral Solution, Oral Tablet
Formula C8H12N4O5
Weight Average: 244.2047
Monoisotopic: 244.080769514
Protein binding

No protein binding reported .

Groups Approved
Therapeutic Class Hepatic viral infections (Hepatitis C)
Manufacturer
Available Country United States
Last Updated: September 19, 2023 at 7:00 am
Ribasphere
Ribasphere

Uses

Ribasphere is used for the treatment of chronic hepatitis C (CHC) virus infection in combination with other antiviral drugs in patients with compensated liver disease not previously treated with interferon alpha and in adult CHC patients coinfected with HIV. Ribasphere should not be used alone.

Ribasphere is also used to associated treatment for these conditions: Chronic Hepatitis C Virus (HCV) Infection, Severe Respiratory Syncytial Virus Infection

How Ribasphere works

Ribasphere 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. Ribasphere 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). Ribasphere 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 .

Ribasphere 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 .

Ribasphere 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 . Ribasphere 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 .

Dosage

Ribasphere dosage

The recommended duration of treatment for patients previously untreated with interferon is 24 to 48 weeks. After 24 weeks of treatment virologic response should be assessed. Treatment discontinuation should be considered in any patient who has not achieved an HCV RNA below the limit of detection of the assay by 24 weeks. There are no safety and efficacy data on treatment for longer than 48 weeks in the previously untreated patient population. In patients who relapse following interferon therapy, the recommended duration of treatment is 24 weeks. There are no safety and efficacy data on treatment for longer than 24 weeks in the relapse patient populations.

Ribasphere + Interferon:Genotype Ribasphere Daily Interferon alpha-2a Duration or interferon alpha-2b.

  • All <75 kg:(400+600) mg 3 MIU 3 times weekly 48 weeks Genotypes subcutaneously (Genotype1&4)
  • >75 kg:(600+600) mg 24 weeks (Genotype2&3)

Ribasphere + Peg-Interferon:

Genotype Ribasphere Daily Peg-Interferon alpha-2a Duration or Peg-interferon alpha-2b:

  • 1 & 4 < 75 kg: (400+600) mg 180 gm once weekly 48 weeks
  • > 75 kg: (600+600) mg subcutaneously 2 & 3 (400+400) mg 24 weeks

Ribasphere may be administered without regard to food, but should be administered in a consistent manner. Drink plenty of water while being treated with this medication; drinking water will decrease the risk of serious side effects.

Side Effects

The most common adverse reactions in adults receiving combination therapy are psychiatric and central nervous system effects, severe ocular disorder, dental and periodontal disorders & growth inhibition in children and adolescents that may be irreversible in some patients. The most common adverse reactions in pediatric subjects were similar to those seen in adults.

Toxicity

Rivabirin and PEG-Interferon Alfa-2A dual therapy is associated with flu-like symptoms, depression, suicide, insomnia, irritability, relapse of drug abuse/overdose, hepatic decompensation in 2% of HIV co-infected patients and bacterial infections each occurring at a frequency of less than 1%. Ribasphere-induced anemia is a dose-dependent adverse effect where reduced hemoglobin levels can be seen within the first 1-2 weeks in therapy. The mechanism of ribavirin-induced anemia has been shown to involve reductions in reticulocyte counts and erythrocyte Na-K pump activity, and increases in K-Cl cotransport, membrane bound IgG, and C3, and erythrocyte band 3 . Oral LD50 in rats is 2700 mg/kg. Intraperitoneal LD50 in mouse is 1300 mg/kg. Potential carcinogenic effects of ribavirin to humans cannot be yet excluded as it demonstrates mutagenic activity in the in vitro mouse lymphoma assay.

Precaution

Birth defects and fetal death with ribavirin: Do not use in pregnancy and for 6 months after treatment. Patients must have a negative pregnancy test prior to therapy, use at least 2 forms of contraception and undergo monthly pregnancy tests. For a male patient, it is very important for his female partner to avoid becoming pregnant during treatment and during the 7 months after treatment and do not have sex with a pregnant women.

Interaction

Nucleoside reverse transcriptase inhibitors or reduce dose or discontinue interferon, ribavirin or both with worsening toxicities

Azathioprine: Concomitant use of azathioprine with ribavirin has been reported to induce severe pancytopenia and may increase the risk of azathioprine-related myelotoxicity.

Food Interaction

  • Avoid alcohol. Ribasphere is used to treat chronic hepatitis C infection; ingesting alcohol may worsen this infection.
  • Take with food. Taking ribavirin with a high-fat meal slows the absorption and increases the AUC and Cmax of ribavirin.

[Moderate] ADJUST DOSING INTERVAL: Food enhances the oral absorption and bioavailability of ribavirin.

Administration of a single oral dose of ribavirin following a high-fat meal delayed absorption (Tmax was doubled) but increased the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) by up to 70% compared to administration in the fasting state.

MANAGEMENT: To ensure maximal oral absorption, ribavirin should be administered with or immediately after a meal.

Volume of Distribution

Ribasphere displays a large volume of distribution .

Elimination Route

Ribasphere is reported to be rapidly and extensively absorbed following oral administration. The average time to reach Cmax was 2 hours after oral administration of 1200 mg ribavirin . The oral bioavailability is 64% following a single oral dose administration of 600mg ribavirin .

Half Life

The terminal half-life of ribavirin following administration of a single oral dose of 1200 mg is about 120 to 170 hours .

Clearance

The total apparent clearance rate after a single oral dose administration of 1200 mg ribavirin is 26L/h .

Elimination Route

The metabolites of ribavirin are renally excreted. After the oral administration of 600mg radiolabeled ribavirin, approximately 61% of the drug was detected in the urine and 12% was detected in the feces. 17% of administered dose was in unchanged form .

Pregnancy & Breastfeeding use

Pregnancy Category X. Ribasphere produced significant embryocidal and/or teratogenic effects in all animal species in which adequate studies have been conducted. Malformations of the skull, palate, eye, jaw, limbs, skeleton and gastrointestinal tract were noted. The incidence and severity of teratogenic effects increased with escalation of the drug dose. Survival of fetuses and offspring was reduced.

Nursing Mothers: It is not known whether Ribasphere is excreted in human milk. Because many drugs are excreted in human milk and to avoid any potential for serious adverse reactions in nursing infants from ribavirin, a decision should be made either to discontinue nursing or therapy with Ribasphere, based on the importance of the therapy to the mother.

Contraindication

Women who are pregnant. Ribasphere may cause fetal harm when administered to a pregnant woman. Ribasphere is contraindicated in women who are or may become pregnant. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus. Patients with hemoglobinopathies (e.g., thalassemia major or sickle-cell anemia). In combination with didanosine. Reports of fatal hepatic failure, as well as peripheral neuropathy, pancreatitis and symptomatic hyperlactatemia/lactic acidosis have been reported in clinical trials.

Special Warning

Pediatric Use: Safety and effectiveness of Ribasphere in combination with Peginterferon has not been established in pediatric patients below the age of 3 years.

Geriatric Use: The risk of toxic reactions to this drug may be greater in patients with impaired renal function. The dose of Ribasphere should be reduced in patients with creatinine clearance less than or equal to 50 ml/min; and the dose of Interferon should be reduced in patients with creatinine clearance less than 30 ml/min.

Storage Condition

Keep out of the reach of children. Keep in a cool & dry place. Protect from light.

Innovators Monograph

You find simplified version here Ribasphere

Ribasphere contains Ribavirin see full prescribing information from innovator Ribasphere Monograph, Ribasphere MSDS, Ribasphere FDA label

FAQ

What is Ribasphere used for?

Ribasphere is a antiviral medication used to treat RSV infection, hepatitis C and some viral hemorrhagic fevers.It is used in combination with injectable interferon alfa-2b, peginterferon alfa-2a, or peginterferon alfa-2b to treat chronic hepatitis C infection. The combination of Ribasphere and peginterferon alfa-2b is used to treat adults and children 3 years of age and older who show symptoms of liver damage.

How safe is Ribasphere?

Ribasphere can cause lung problems such as trouble breathing and pneumonia. It can also cause pulmonary hypertension. Symptoms of lung problems can include: shortness of breath.

How does Ribasphere work?

Ribasphere work by direct antiviral activity against a number of DNA and RNA viruses by increasing the mutation frequency in the genomes of several RNA viruses.

What are the common side effects of Ribasphere?

Common side effects of Ribasphere are include:

  • Acid or sour stomach
  • being forgetful
  • belching
  • blurred vision
  • bone pain
  • change in taste or bad, unusual, or unpleasant (after) taste
  • cracked, scaly skin
  • crusting, irritation, itching, or reddening of the skin
  • difficulty with moving
  • dizziness or lightheadedness
  • feeling of constant movement of self or surroundings
  • hair loss or thinning of the hair
  • heartburn
  • indigestion
  • lack or loss of strength
  • menstrual changes
  • pain or tenderness around the eyes and cheekbones
  • rash
  • sensation of spinning
  • sneezing
  • stomach discomfort, upset, or pain
  • stuffy nose
  • swelling
  • swollen joints
  • weight loss

Is Ribasphere safe during pregnancy?

Ribasphere is prescribed for chronic hepatitis C and is contraindicated in women who are pregnant and in the male sexual partners of women who are pregnant. Both sexes are advised to avoid pregnancy for 6 months after exposure.

Is Ribasphere safe during breastfeeding?

The manufacturer recommends that due to the potential for serious adverse reactions in nursing infants, a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

Can I drink alcohol with Ribasphere?

Avoid drinking alcohol.Ribasphere can make your liver problems worse. Using this medicine will not prevent you from passing hepatitis to other people.

When should I take Ribasphere?

It is usually taken with food twice a day, in the morning and the evening. Take Ribasphere at around the same times every day.

Should Ribasphere be taken with food?

Yes, Ribasphere is taken with food to reduce nausea. If you miss a dose: If you miss a dose of Ribasphere, take the missed dose as soon as possible the same day.

How long can I take Ribasphere?

Ribasphere take for 24 to 48 weeks or longer.

Who can not take Ribasphere?

Ask your doctor about any risk.Ribasphere is not approved for use by anyone younger than 3 years old. Ribasphere tablets are not approved for use by anyone younger than 5 years old.

How long does Ribasphere stay in my system?

Ribasphere can stay in your body's tissues for up to six months after you stop taking it.

Is Ribasphere used for Covid?

It was as thought that Ribasphere might be useful for treating coronavirus infection because of its broad-spectrum inhibition of RNA viruses. Several studies have shown that Ribasphere has useful activity against SARS-CoV in vitro.

Is Ribasphere an antiviral?

Ribasphere is in a class of antiviral medications called nucleoside analogues.

What happens if I miss a dose of Ribasphere?

Take the missed dose on the same day you remember it. Skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
Get your prescription refilled before you run out of medicine completely.

Why does Ribasphere cause anemia?

because red blood cells lack dephosphorylation enzymes, Ribasphere accumulates in cells and destroys the cells, causing hemolytic anemia. The pretreatment hemoglobin concentration could be a significant factor in Ribasphere-induced anemia.

How do I take Ribasphere pills?

Ribasphere capsules are to be administered orally each day in two divided doses (morning and evening) with food.

What happen If I stop taking Ribasphere?

If you stop taking Ribasphere won’t work to treat your hepatitis C virus infection. The infection will continue to progress and cause more damage to your liver. This infection may be deadly if not treated properly.

What happen if I overdose of Ribasphere?

You could have dangerous levels of Ribasphere in your body. You could be at increased risk of kidney problems, bleeding inside your body, or heart attack.

*** Taking medicines without doctor's advice can cause long-term problems.
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