Palivizumab

Summary

Palivizumab is a recombinant humanized IgG1κ monoclonal antibody that targets the F (fusion) protein of RSV (respiratory syncytial virus).  Binding of palivizumab to it's target helps to prevent infection with RSV and is indicated for the seasonal prevention of serious lower respiratory tract disease caused by RSV in pediatric patients at significantly increased risk of morbidity and mortality due to RSV infection, including infants with CLD (chronic lung disease) and those with hemodynamically significant cyanotic and acyanotic CHD (congenital heart disease).

Palivizumab is administered by intramuscular injection and has been used in more than one million children in the U.S. since its introduction in 1998. Safety and efficacy were established in infants with bronchopulmonary dysplasia (BPD), infants with a history of premature birth (≤35 weeks gestational age), and children with hemodynamically significant congenital heart disease (CHD).  Per published recommendations, the first dose of palivizumab should be administered prior to commencement of the RSV season. Patients, including those who develop an RSV infection, should continue to receive monthly doses throughout the RSV season.

Very rare cases (<1 per 100,000 patients) of anaphylaxis and rare (<1 per 1,000 patients) hypersensitivity reactions have been reported with palivizumab. Cases of anaphylaxis were reported following re-exposure to palivizumab and rare severe hypersensitivity reactions occurred on initial exposure or re-exposure. According to the manufacturer, if a severe hypersensitivity reaction occurs, therapy with palivizumab should be permanently discontinued. If milder hypersensitivity reaction occurs, caution should be used on re-administration of palivizumab. In post-marketing reports, very rare cases (<1 case per 100,000 patients) of severe thrombocytopenia (platelet count <50,000/microliter) have been reported.

In clinical trials, the most common adverse events occurring at least 1% more frequently in palivizumab-treated patients than controls were upper respiratory infection, otitis media, fever, and rhinitis. Cyanosis and arrhythmia were seen in children with CHD. There have also been post-marketing reports of injection site reactions.

Palivizumab is not reported to interfere with the response to vaccines.

Brand Name

Synagis

Other Names

MEDI-493

Molecular Target

RSV F (fusion) protein

Molecular Structure

humanized IgG1κ

Licensed Indication, Major Target Diseases

prevention of serious lower respiratory tract disease caused by respiratory syncytial virus (RSV) in pediatric patients at high risk of RSV disease

Manufacturer/Distributor

MedImmune

References