The United States Food and Drug Administration recently issued emergency use authorization for 2 mRNA vaccines for preventing COVID-19 disease caused by SARS-CoV-2 virus infections. BNT162b2 from Pfizer-BioNTech and mRNA-1273 by Moderna are planned for use in mass-immunization programs to curb the pandemic. A brief overview of COVID-19 mRNA vaccines is provided, describing the SARS-CoV-2 RNA, how mRNA vaccines work and the advantages of mRNA over other vaccine platforms. The Pfizer-BioNTech collaboration journey to short-list mRNA vaccine candidates and finally selecting BNT162b2 based on safety data is outlined, followed by the Phase 3 study of BNT162b2 demonstrating 95% efficacy in preventing COVID-19 infections. Studies regarding mRNA-1273 (Moderna) are described, including extended immunogenicity data up to 119 days. The Phase 3 COVE study of mRNA-1273 eventually showed vaccine efficacy of 94.5%. Recommendations for future mRNA vaccine development are provided, including ongoing safety surveillance, evaluation in under-represented groups in previous studies and improving mRNA vaccine thermostability. Finally, further logistical considerations are required for manufacturing, storing, distribution and implementing mass vaccination programs to curb the pandemic.
Review of COVID-19 mRNA Vaccines: BNT162b2 and mRNA-1273