Palivizumab, sold under the brand name Synagis, is a monoclonal antibody produced by recombinant DNA technology used to prevent severe disease caused by respiratory syncytial virus (RSV) infections. It is recommended for infants at high-risk for RSV due to conditions such as prematurity or other medical problems including heart or lung diseases.The most common side effects include fever and rash.Palivizumab is a humanized monoclonal antibody (IgG) directed against an epitope in the A antigenic site of the F protein of RSV. In two phase III clinical trials in the pediatric population, palivizumab reduced the risk of hospitalization due to RSV infection by 55% and 45%. Palivizumab is dosed once a month via intramuscular (IM) injection, to be administered throughout the duration of the RSV season, which in based on past trends has started in Mid-September to Mid-November.Palivizumab targets the fusion protein of RSV, inhibiting its entry into the cell and thereby preventing infection. Palivizumab was approved for medical use in 1998. Medical use
Palivizumab is indicated for the prevention of serious lower respiratory tract disease requiring hospitalization caused by the respiratory syncytial virus (RSV) in children at high risk for RSV disease:
children born at 35 weeks of gestation or less and less than six months of age at the onset of the RSV season;
children less than two years of age and requiring treatment for bronchopulmonary dysplasia within the last six months;
children less than two years of age and with hemodynamically significant congenital heart disease.The American Academy of Pediatrics has published guidelines for the use of palivizumab.
This enhanced form of the disease led to 80% hospitalization in the recipients of FIRSV compared to 5% in the control group. Additionally, 2 fatalities occurred among the vaccine recipients upon reinfection in subsequent years. Subsequent attempts to develop an attenuated live virus vaccine with optimal immune response and minimal reactogenicity have been unsuccessful. Further research on animal subjects suggested that intravenously administered immunoglobulin with high RSV neutralizing activity can protect against RSV infection. In 1995, the U.S. Food and Drug Administration (FDA) approved the use of RespiGam (RSV-IGIV) for the prevention of serious lower respiratory tract infection caused by RSV in children younger than 24 months of age with bronchopulmonary dysplasia or a history of premature birth. The success of the RSV-IGIV demonstrated efficacy in immunoprophylaxis and prompted research into further technologies. Thus, Palivizumab was developed as an antibody that was found to be fifty times more potent than its predecessor. This antibody has been widely used for RSV since 1998 when it was approved. Palivizumab, originally known as MEDI-493, was developed as an RSV immune prophylaxis tool that was easier to administer and more effective than the current tools of that time (the 1990s). It was developed over a 10-year period by MedImmune Inc. by combining human and mouse DNA. Specifically, antibody production was stimulated in a mouse model following immunization with RSV. The antibody-producing B cells were isolated from the mouses spleen and fused with mouse myeloma cell lines.