Comparative immunogenicity and reactogenicity of heterologous ChAdOx1 nCoV-19-priming and BNT162b2 or mRNA-1273-boosting with homologous COVID-19 vaccine regimens

Multiple formulations and technologies for vaccinating against SARS-CoV-2 exist but how the use of these in homologous or heterologous format impacts immunogenicity is far from clear. Here the authors compare a range of heterologous and homologous SARS-CoV-2 vaccination strategies and assess the induced humoral and cellular immune response. The following heterologous and homologous vaccination regimens were tested for immunogenicity and reactogenicity in a in a convenience cohort of 331 healthy individuals. ChAdOx1-nCoV-19 followed by BNT162b2 (n=66) ChAdOx1-nCoV-19 followed by mRNA-1273 (n=101) BNT162b2 followed by BNT162b2 (n=43) mRNA-1273 followed by mRNA-1273 (n=59) ChAdOx1-nCoV-19 followed by ChAdOx1-nCoV-19 (n=62)