Ribavirin

What it is and how it works

Mechanism of Action In cell cultures the inhibitory activity of ribavirin for respiratory syncytial virus (RSV) is selective. The mechanism of action is unknown. Reversal of the in vitro antiviral activity by guanosine or xanthosine suggests ribavirin may act as an analogue of these cellular metabolites. Microbiology Ribavirin has demonstrated antiviral activity against RSV in vitro 1 and in experimentally infected cotton rats. 2 Several clinical isolates of RSV were evaluated for ribavirin susceptibility by plaque reduction in tissue culture. Plaques were reduced 85-98% by 16 mcg/mL; however, results may vary with the test system.

Indications

INDICATIONS AND USAGE Ribavirin for Inhalation Solution, USP is indicated for the treatment of hospitalized infants and young children with severe lower respiratory tract infections due to RSV. Treatment early in the course of severe lower respiratory tract infection may be necessary to achieve efficacy. Only severe RSV lower respiratory tract infection should be treated with Ribavirin for Inhalation Solution, USP. The vast majority of infants and children with RSV infection have disease that is mild, self-limited, and does not require hospitalization or antiviral treatment. Many children with mild lower respiratory tract involvement will require shorter hospitalization than would be required for a full course of Ribavirin for Inhalation Solution, USP aerosol (3 to 7 days) and should not be treated with the drug. Thus the decision to treat with Ribavirin for Inhalation Solution, USP should be based on the severity of the RSV infection.

Dosage and administration (summary)

DOSAGE AND ADMINISTRATION BEFORE USE, READ THOROUGHLY THE BAUSCH HEALTH SMALL PARTICLE AEROSOL GENERATOR SPAG-2 INSTRUCTIONS FOR USE FOR SMALL PARTICLE AEROSOL GENERATOR OPERATING INSTRUCTIONS. AEROSOLIZED RIBAVIRIN FOR INHALATION SOLUTION, USP HAS NOT BEEN TESTED WITH ANY OTHER AEROSOL GENERATING DEVICE. The recommended treatment regimen is 20 mg/mL Ribavirin for Inhalation Solution, USP as the starting solution in the drug reservoir of the SPAG-2 unit, with continuous aerosol administration for 12-18 hours per day for 3 to 7 days. Using the recommended drug concentration of 20 mg/mL the average aerosol concentration for a 12 hour delivery period would be 190 mcg/L of air.

Contraindications

CONTRAINDICATIONS Ribavirin for Inhalation Solution, USP is contraindicated in individuals who have shown hypersensitivity to the drug or its components, and in women who are or may become pregnant during exposure to the drug. Ribavirin has demonstrated significant teratogenic and/or embryocidal potential in all animal species in which adequate studies have been conducted (rodents and rabbits).

Warnings and precautions

WARNINGS SUDDEN DETERIORATION OF RESPIRATORY FUNCTION HAS BEEN ASSOCIATED WITH INITIATION OF AEROSOLIZED RIBAVIRIN FOR INHALATION SOLUTION, USP USE IN INFANTS. Respiratory function should be carefully monitored during treatment. If initiation of aerosolized Ribavirin for Inhalation Solution, USP treatment appears to produce sudden deterioration of respiratory function, treatment should be stopped and reinstituted only with extreme caution, continuous monitoring, and consideration of concomitant administration of bronchodilators.

Pregnancy

Ribavirin has demonstrated significant teratogenic and/or embryocidal potential in all animal species in which adequate studies have been conducted. Teratogenic effects were evident after single oral doses of 2.5 mg/kg or greater in the hamster, and after daily oral doses of 0.3 and 1.0 mg/kg in the rabbit and rat, respectively (estimated human equ…

Storage and supply

HOW SUPPLIED Ribavirin for Inhalation Solution, USP is supplied in one-pack and four-pack counts containing 100 mL glass vials with 6 grams of Sterile, lyophilized drug which is to be reconstituted with 300 mL Sterile Water for Injection, USP or Sterile Water for Inhalation (no preservatives added) and administered only by a small particle aerosol …

Source: Ribavirin (Ribavirin) — US FDA prescribing information, 2019-05-01, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.