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The DOI matches its Crossref record; 21 of the 21 references it cites were found in a registry or an index.

Efficacy of a Fourth Dose of Covid-19 mRNA Vaccine against Omicron

Open access
Regev-Yochay, Gili, Gonen, Tal, Gilboa, Mayan, Mandelboim, Michal, Indenbaum, Victoria, Amit, Sharon, Meltzer, Lilac, Asraf, Keren, Cohen, Carmit, Fluss, Ronen, Biber, Asaf, Nemet, Ital, Kliker, Limor, Joseph, Gili, Doolman, Ram, Mendelson, Ella, Freedman, Laurence S., Harats, Dror, Kreiss, Yitshak, Lustig, Yaniv·2022·New England Journal of Medicine
DOI 10.1056/nejmc2202542
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Abstract

Abstract BACKGROUND Following the emergence of the Omicron variant of concern, we investigated immunogenicity, efficacy and safety of BNT162b2 or mRNA1273 fourth dose in an open-label, clinical intervention trial. METHODS Primary end-points were safety and immunogenicity and secondary end-points were vaccine efficacy in preventing SARS-CoV-2 infections and COVID-19 symptomatic disease. The two intervention arms were compared to a matched control group. Eligible participants were healthcare-workers (HCW) vaccinated with three BNT162b2 doses, and whose IgG antibody levels were ≤700 BAU (40-percentile). IgG and neutralizing titers, direct neutralization of live VOCs, and T-cell activation were assessed. All participants were actively screened for SARS-CoV-2 infections on a weekly basis. RESULTS Of 1050 eligible HCW, 154 and 120 were enrolled to receive BNT162b2 and mRNA1273, respectively, and compared to 426 age-matched controls. Recipients of both vaccine types had a ∼9-10-fold increase in IgG and neutralizing titers within 2 weeks of vaccination and an 8-fold increase in live Omicron VOC neutralization, restoring titers to those measured after the third vaccine dose. Breakthrough infections were common, mostly very mild, yet, with high viral loads. Vaccine efficacy against infection was 30% (95%CI:-9% to 55%) and 11% (95%CI:-43% to +43%) for BNT162b2 and mRNA1273, respectively. Local and systemic adverse reactions were reported in 80% and 40%, respectively. CONCLUSIONS The fourth COVID-19 mRNA dose restores antibody titers to peak post-third dose titers. Low efficacy in preventing mild or asymptomatic Omicron infections and the infectious potential of breakthrough cases raise the urgency of next generation vaccine development. Trial registration number clicaltrials.gov : NCT05231005 , NCT05230953

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Metadata

Authors
Regev-Yochay, G., Gonen, T., Gilboa, M., Mandelboim, M., Indenbaum, V., Amit, S., Meltzer, L., Asraf, K., Cohen, C., Fluss, R., Biber, A., Nemet, I., Kliker, L., Joseph, G., Doolman, R., Mendelson, E., Freedman, L. S., Harats, D., Kreiss, Y., & Lustig, Y.
Venue
New England Journal of Medicine
Publisher
Massachusetts Medical Society
Published
2022-04-07
Volume
386
Issue
14
Pages
1377-1380
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
DOI
10.1056/nejmc2202542
OpenAlex
W4220928249
Cited by
386
References
21
FWCI
43.32
Type
journal article
Language
en
Open access
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CoChat. (2026). Citation check: Efficacy of a Fourth Dose of Covid-19 mRNA Vaccine against Omicron. https://app.cochat.ai/papers/10.1056/nejmc2202542
The paper
Regev-Yochay, G., Gonen, T., Gilboa, M., Mandelboim, M., Indenbaum, V., Amit, S., Meltzer, L., Asraf, K., Cohen, C., Fluss, R., Biber, A., Nemet, I., Kliker, L., Joseph, G., Doolman, R., Mendelson, E., Freedman, L. S., Harats, D., Kreiss, Y., & Lustig, Y. (2022). Efficacy of a Fourth Dose of Covid-19 mRNA Vaccine against Omicron. New England Journal of Medicine. https://doi.org/10.1056/nejmc2202542

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.