#NEW FINDINGS ABOUT COVID VACCINE SERIES#

Researchers gave participants a second booster of 30 µg of Pfizer bivalent BA.4/5 and compared the results with those of another study which had used the Pfizer original formulation for the second booster.

#NEW FINDINGS ABOUT COVID VACCINE SERIES#

4 Vaccine immunogenicity and efficacy – Pfizer Pfizer bivalent vaccines Pfizer bivalent original/Omicron BA.4/5 formulationĪn immunogenicity study (Study C4591044) investigated results in adolescents and adults aged 12 years and over who had received a primary series and first booster of Pfizer original formulation. Combined VE of Pfizer and Moderna BA.1 vaccines was 65% (95% CI: 47 – 77) for BA.1, and combined VE of Pfizer and Moderna BA.4/5 vaccines was 76% (95% CI: 65 – 83). An observational study in Japan conducted during a BA.5- dominant period found that the effectiveness of BA.4/5 and BA.1 vaccines against symptomatic illness was similar. 3īivalent vaccines also offer some protection against symptomatic infection. 2ĭata from the UK Health Security Agency in people aged ≥50 years demonstrate some waning of the incremental protection from BA.1 booster doses. 2 In this latter study, VE estimates of Pfizer and Moderna BA.4/5 vaccines were similar (63.8% vs 60.4% respectively). Similarly, the effectiveness of Pfizer or Moderna BA.4/5 vaccines against hospitalisation or death during an Omicron-dominant period was estimated at 61.8% (95% CI: 48.2– - 71.8) in a US test-negative case control study. Early vaccine effectiveness studies demonstrate that both BA.4/5- and BA.1- based bivalent vaccines offer excellent protection against hospitalisation and death from COVID-19current SARS-CoV-2 strains for several months.Ī population-wide cohort study conducted across 4 Nordic countries during an Omicron-dominant study period reported the combined vaccine effectiveness (CVE) of Pfizer and Moderna BA.1 vaccines against hospitalisation at 74% (95% CI: 68.6 – 79.4%), and of BA.4/5 vaccines at 80.5% (95% CI: 69.5 – 91.5%). Their preferential use for the primary course is based on superior immunogenicity and vaccine effectiveness against Omicron sub-variants, when evaluated as booster doses. There are no direct data on the immunogenicity or efficacy of bivalent COVID-19 vaccines for primary course vaccination. Effectiveness of bivalent COVID-19 vaccines Unless indicated, efficacy and effectiveness estimates relate to protection against the ancestral or pre-Omicron SARS-CoV-2 variants. Vaccine effectiveness refers to the protection the vaccine has provided during ‘real world’ use in the population use.

Vaccine efficacy indicates the level of protection a vaccine has demonstrated in clinical trials. On this page About vaccine efficacy and effectiveness

New findings about covid vaccine