Dosage & Administration
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.
Ribavirin + Interferon: Genotype Ribavirin 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)
Ribavirin + Peg-Interferon: Genotype Ribavirin 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
Ribavirin 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.
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.
Pregnancy & Lactation
Pregnancy Category X. Ribavirin 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 Ribavirin 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 Ribavirin, based on the importance of the therapy to the mother.
Precautions & Warnings
Use in Special Populations
Pediatric Use: Safety and effectiveness of Ribavirin 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 Ribavirin 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.