tozinameran + riltozinameran (Pfizer)

Comirnaty Bivalent is a next-generation mRNA vaccine developed by Pfizer and BioNTech to provide broader protection against COVID-19. It is a bivalent formulation containing two messenger RNA (mRNA) components: tozinameran, which encodes the spike protein of the original SARS-CoV-2 (Wuhan-Hu-1) strain, and riltozinameran, which encodes the spike protein of the Omicron BA.4 and BA.5 subvariants. The vaccine utilizes lipid nanoparticle (LNP) technology to deliver these genetic instructions into host cells, where they are translated into spike proteins that trigger a robust adaptive immune response, including the production of neutralizing antibodies and T-cell activation. It is primarily indicated as a booster dose to enhance immunity against evolving variants of the virus.

Brand names

Comirnaty BivalentComirnaty Original/Omicron BA.4-5

Other names

Pfizer-BioNTech COVID-19 Vaccine, BivalentCOVID-19 mRNA Vaccine (nucleoside modified)