Palivizumab and Motavizumab

Palivizumab and motavizumab are both monoclonal antibodies developed for the prevention of serious lower respiratory tract disease caused by Respiratory Syncytial Virus (RSV) in high-risk infants. Palivizumab, marketed under the brand name Synagis, is a humanized IgG monoclonal antibody that targets an epitope in the A antigenic site of the RSV fusion (F) protein. By binding to this protein, palivizumab inhibits the entry of the virus into cells and prevents cell-to-cell and virus-to-cell fusion, thereby preventing infection. It was approved for medical use in 1998. Motavizumab is a second-generation, affinity-optimized humanized IgG1 monoclonal antibody derived from palivizumab. It also targets the antigenic site A on the RSV F protein but exhibits greater neutralizing activity and affinity compared to palivizumab. Motavizumab was investigated as an improved prophylactic agent against RSV; however, its development for RSV prevention was discontinued after the FDA declined approval, citing concerns about its efficacy superiority over palivizumab and a higher incidence of allergic skin reactions. Both drugs were developed by MedImmune, a subsidiary of AstraZeneca.

Brand names

Synagis