group b streptococcus capsular polysaccharide type IV conjugated to CRM197

This drug is a monovalent conjugate vaccine component targeting Group B Streptococcus (GBS) serotype IV. It consists of the capsular polysaccharide (CPS) of GBS serotype IV covalently linked to CRM197, a non-toxic mutant of diphtheria toxin that serves as a carrier protein to enhance immunogenicity. This conjugate is a key constituent of Pfizer's hexavalent GBS vaccine candidate, GBS6 (PF-06760805). The vaccine is primarily intended for maternal immunization during pregnancy; it induces the production of serotype-specific IgG antibodies in the mother, which are then actively transported across the placenta to the fetus. This process provides the neonate with passive immunity against invasive GBS disease, including sepsis, pneumonia, and meningitis, during the first months of life. Serotype IV is one of the six major serotypes responsible for the global burden of GBS disease. The mechanism of action relies on the induction of functional opsonophagocytic antibodies that facilitate the recognition and clearance of GBS by the infant's immune system.

Other names

GBS Type IV-CRM197 conjugateStreptococcus agalactiae serotype IV capsular polysaccharide-CRM197 conjugate