Respiratory Syncytial Virus Fusion protein and Influenza Hemagglutinin (RSV F / HA)

This target profile describes the combined antigenic components involved in the coadministration of vaccines for Respiratory Syncytial Virus (RSV) and Influenza. The primary molecular targets are the RSV Fusion (F) protein, specifically in its metastable prefusion (preF) conformation, and the Influenza Hemagglutinin (HA) protein. RSV preF is critical for the virus to fuse with host cell membranes, and antibodies targeting this specific conformation are highly potent in neutralizing the virus (McLellan et al., 2013). Influenza HA is the major surface glycoprotein of the flu virus, mediating binding to sialic acid receptors on host cells. In clinical practice, coadministration of vaccines like Abrysvo or Arexvy with seasonal influenza vaccines aims to provide dual protection against these major respiratory pathogens, particularly in older adults (Schmoele-Thoma et al., 2022). Research focuses on ensuring that the combined immune response remains robust, with non-inferior antibody titers compared to separate administration, while maintaining a manageable safety profile (Pfizer, 2022; GSK, 2022).

Other names

RSV preFInfluenza HARSV-FHemagglutininRSVpreFRSV F proteinFlu HARespiratory Syncytial Virus prefusion F protein

Induction of neutralizing antibodies that bind to the prefusion conformation of the RSV F protein and the globular head or stalk of the influenza hemagglutinin protein, thereby preventing viral attachment and fusion with host cell membranes (McLellan et al., 2013; Schmoele-Thoma et al., 2022).