Monoclonal Antibodies for Prevention of Respiratory Syncytial Virus Infection.

Respiratory syncytial virus (RSV) is the leading cause of hospitalizations in infants worldwide. Palivizumab, a humanized monoclonal antibody against the RSV F protein, is the only licensed agent for prevention of severe RSV infection in high-risk infants. Palivizumab is administered intramuscularly, every month during the RSV season, usually 5 doses are required. In recent years, the resolution of the structure of the RSV F protein, with identification of potent neutralizing epitopes, and new technologies for production of monoclonal antibodies (mAbs) have facilitated the development of new alternative strategies for the prevention of RSV infections. One promising approach is a new generation of mAbs directed to new neutralizing epitopes and with prolonged half life. These enhanced mAbs are expected to provide adequate protection during the complete RSV season with a single intramuscular (IM) dose. The long-term goal of this approach is to provide passive immunization for the prevention of RSV lower respiratory tract infection to all infants (preterm and full term) in the first months of life before their initial exposure to RSV.