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 respiratory syncytial virus. 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. The presence of an underlying condition such as prematurity, immunosuppression or cardiopulmonary disease may increase the severity of clinical manifestations and complications of RSV infection.
Use of aerosolized ribavirin for inhalation solution, USP in patients requiring mechanical ventilator assistance should be undertaken only by physicians and support staff familiar with this mode of administration and the specific ventilator being used (see WARNINGS, and DOSAGE AND ADMINISTRATION).
Diagnosis
RSV infection should be documented by a rapid diagnostic method such as demonstration of viral antigen in respiratory tract secretions by immunofluorescence3,4or ELISA5 before or during the first 24 hours of treatment. Treatment may be initiated while awaiting rapid diagnostic test results. However, treatment should not be continued without documentation of RSV infection. Non-culture antigen detection techniques may have false positive or false negative results. Assessment of the clinical situation, the time of year and other parameters may warrant reevaluation of the laboratory diagnosis.
Description of Studies
Non-Mechanically-Ventilated Infants:
In two placebo controlled trials in infants hospitalized with RSV lower respiratory tract infection, aerosolized ribavirin for inhalation solution, USP treatment had a therapeutic effect, as judged by the reduction in severity of clinical manifestations of disease by treatment day 3.3,4 Treatment was most effective when instituted within the first 3 days of clinical illness. Virus titers in respiratory secretions were also significantly reduced with ribavirin for inhalation solution, USP in one of these original studies.4 Additional controlled studies conducted since these initial trials of aerosolized ribavirin for inhalation solution, USP in the treatment of RSV infection have supported these data.
Mechanically-Ventilated Infants
: A randomized, double-blind, placebo-controlled evaluation of aerosolized ribavirin for inhalation solution, USP at the recommended dose was conducted in 28 infants requiring mechanical ventilation for respiratory failure caused by documented RSV infection.6 Mean age was 1.4 months (SD, 1.7 months). Seven patients had underlying diseases predisposing them to severe infection and 21 were previously normal. Aerosolized ribavirin for inhalation solution, USP treatment significantly decreased the duration of mechanical ventilation required (4.9 vs. 9.9 days, p=0.01) and duration of required supplemental oxygen (8.7 vs. 13.5 days, p=0.01). Intensive patient management and monitoring techniques were employed in this study. These included endotracheal tube suctioning every 1 to 2 hours; recording of proximal airway pressure, ventilatory rate, and FlO2 every hour; and arterial blood gas monitoring every 2 to 6 hours. To reduce the risk of ribavirin for inhalation solution, USP precipitation and ventilator malfunction, heated wire tubing, two bacterial filters connected in series in the expiratory limb of the ventilator (with filter changes every 4 hours), and water column pressure release valves to monitor internal ventilator pressures were used in connecting ventilator circuits to the SPAG-2.
Employing these techniques, no technical difficulties with ribavirin for inhalation solution, USP administration were encountered during the study. Adverse events consisted of bacterial pneumonia in one case, staphyloccus bacteremia in one case and two cases of post-extubation stridor. None were felt to be related to ribavirin for inhalation solution, USP administration.