Vaccine efficacy against SARS-CoV-2 for Pfizer BioNTech, Moderna, and AstraZeneca vaccines: a systematic review

Abstract

The purpose of this systematic review was to report on the vaccine efficacy (VE) of three SARS-CoV-2 vaccines approved by Health Canada: Pfizer BioNTech, Moderna, and AstraZeneca. Four databases were searched for primary publications on population-level VE. Ninety-two publications matched the inclusion criteria, and the extracted data were separated by vaccine type: mRNA vaccines (Pfizer and Moderna) and the AstraZeneca vaccine. The median VE for PCR-positive patients and various levels of clinical disease was determined for the first and second doses of both vaccine types against multiple SARS-CoV-2 variants. The median VE for PCR-positive infections against unidentified variants from an mRNA vaccine was 64.5 and 89%, respectively, after one or two doses. The median VE for PCR-positive infections against unidentified variants from the AstraZeneca vaccine was 53.4 and 69.6%, respectively, after one or two doses. The median VE for two doses of mRNA for asymptomatic, symptomatic, and severe infection against unidentified variants was 85.5, 93.2, and 92.2%, respectively. The median VE for two doses of AstraZeneca for asymptomatic, symptomatic, and severe infection against unidentified variants was 69.7, 71, and 90.2%, respectively. Vaccine efficacy numerically increased from the first to the second dose, increased from the first 2 weeks to the second 2 weeks post-vaccination for both doses, but decreased after 4 months from the second dose. Vaccine efficacy did not differ by person's age.

Effectiveness of the SARS-CoV-2 Vaccination in Preventing Severe Disease-Related Outcomes: A Population-Based Study in the Italian Province of Bolzano (South Tyrol)

“…In conclusion, the findings of our study support vaccination against SARS-CoV-2, in line with other population studies and systematic reviews [ 33 – 35 ].…”

Frequency of SARS-CoV-2 Infections among Healthcare Workers in Germany: 3-Year Follow-Up Study

“…These discrepancies arise from the prioritization of healthcare workers with frequent exposure to COVID-19 patients for vaccination, leading them to receive available vaccines such as the vector-based vaccine from AstraZeneca initially, whereas personnel with less exposure to COVID-19 patients were vaccinated at a later stage. The vaccine efficacy against SARS-CoV-2 infection after two doses of vaccine was reported as 95% for Comirnaty ® (BioNTech/Pfizer), 94.1% for Spikevax ® (Moderna), and 79% for Vaxzevria (AstraZeneca) [ 24 ]. Of note, heterologous prime-boost vaccinations, combining an mRNA vaccine with the vector-based vaccine (Vaxzevria), resulted in markedly higher levels of neutralizing antibody titers compared to vaccinations with either Vaxzevria alone or an mRNA vaccine alone [ 25 ].…”

Optimizing mRNA-Loaded Lipid Nanoparticles as a Potential Tool for Protein-Replacement Therapy

“…The success of nucleoside-modified mRNA-LNP vaccines, developed by Moderna and Pfizer/BioNTech against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has marked a significant milestone in this field. These licensed vaccines have demonstrated the potential of LNPs as excellent vehicles for delivering nucleoside-modified mRNA [ 1 ].…”