Safety and Immunogenicity of a Bivalent SARS-CoV-2 Protein Booster Vaccine, SCTV01C in Adults Previously Vaccinated with Inactivated Vaccine: A Randomized, Double-blind, Placebo-controlled Phase 1/2 Clinical Trial.

In this journal, Liu and colleagues evaluated the immunogenicity of seven COVID-19 vaccines given as third dose boosters following two doses of primary series of ChAdOx1 nCov-19 or BNT162b2.1 However, with the emergence of the SARS-CoV-2 variants, existing evidence shows the waning protection of COVID-19 primary/booster vaccination and the reduced effectiveness of the monovalent vaccines developed based on the original SARS-CoV-2 strain against COVID-19.2 Recent evidences indicated that multivalent booster vaccination could provide significant additional protection against symptomatic SARS-CoV-2 infection in persons who had previously received monovalent vaccine doses.