Palivizumab (Synagis) is a humanized monoclonal antibody
directed against the highly conserved A antigenic
site of the F protein on the surface of RSV. It contains
95% human and 5% murine antibody sequences and
tends to have little immunogenicity in humans.
Palivizumab is composed of the human framework region
of the IgG-1κ-chain joined to the antigen-binding regions of a mouse monoclonal antibody. Palivizumab
neutralizes RSV and inhibits its ability to fuse with host
cell membranes. Resistant strains of RSV have been derived
in vitro but have not been found in clinical isolates
to date.
Palivizumab is used to prevent serious lower respiratory
tract infection due to RSV. It is used only in high-risk
children who are younger than 24 months of age and
have bronchopulmonary dysplasia or chronic lung disease
that required treatment in the previous 6 months.
It is also indicated for premature infants (less than 32
weeks’ gestation) until the age of 6 to 12 months.
Palivizumab can reduce the incidence of RSV-related
hospitalization by approximately half.The safety and efficacy
of palivizumab in the treatment of RSV disease
have not been established.
Serious adverse reactions caused by palivizumab are
rare.Mild erythema and pain may occur at the injection
site.Although no anaphylactoid reactions have been reported
to date, the possibility of this reaction exists because
palivizumab is a protein.
