Neutralizing Activity of BNT162b2-Elicited Serum
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Variant SARS-CoV-2 and BNT162b2 Vaccine How well do serum samples obtained from persons injected with the BNT162b2 vaccine neutralize the P.1, B.1.1.7, and B.1.135 lineages of SARS-CoV-2, first ide...
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- Findingown data§ Neutralizing Activity of BNT162b2-Elicited Serum
Almost all serum samples neutralized the tested viruses at titers above 1:40.
“Almost all of them did so at titers higher than 1:40.”
Quote in the paperSubstantial claim - Interpretationown data§ Neutralizing Activity of BNT162b2-Elicited Serum
The B.1.1.7-spike and P.1-spike viruses were neutralized to a roughly similar degree as USA-WA1/2020.
“Thus, as compared with neutralization of USA-WA1/2020, neutralization of B.1.1.7-spike and P.1-spike viruses was roughly equivalent, and neutralization of B.1.351-spike virus was robust but lower.”
Quote in the paperSubstantial claim - Premisecitation§ Neutralizing Activity of BNT162b2-Elicited Serum
In a randomized, placebo-controlled trial of about 44,000 participants, BNT162b2 immunization was 95% effective against Covid-19.
“In a randomized, placebo-controlled clinical trial involving approximately 44,000 participants, immunization conferred 95% efficacy against coronavirus disease 2019 (Covid-19).1”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [1] Polack FP, Thomas SJ, Kitchin N, et al. Safety and efficacy of the BNT162b2 mRNA Covid-19 vaccine. N Engl J Med 2020; 383: 2603- 2615. 33301246 PMC7745181 source
Not checked in the free run.
- Interpretationown data§ Neutralizing Activity of BNT162b2-Elicited Serum
The full set of B.1.351-spike mutations produced lower neutralizing titers than either subset of those mutations.
“Our data are also consistent with lower neutralization titers against the virus with the full set of B.1.351-spike mutations than against virus with either subset of mutations.”
Quote in the paperSubstantial claim - Interpretationown data§ Neutralizing Activity of BNT162b2-Elicited Serum
The receptor-binding site substitutions K417N, E484K, and N501Y affect neutralization more than the N-terminal domain 242-244 deletion.
“Our findings also suggest that mutations that result in amino acid substitutions K417N, E484K, and N501Y in the receptor-binding site have a greater effect on neutralization than the 242–244 deletion affecting the N-terminal domain of the spike protein.”
Quote in the paperSubstantial claim
- Premisecitation§ Neutralizing Activity of BNT162b2-Elicited Serum
Vaccination with BNT162b2 induces CD8+ T-cell responses capable of recognizing several variants.
“BNT162b2 immunization elicits CD8+ T-cell responses that recognize multiple variants.5”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [5] Skelly DT, Harding AC, Gilbert-Jaramillo J, et al. Vaccine-induced immunity provides more robust heterotypic immunity than natural infection to emerging SARS-CoV-2 variants of concern. February 9, 2021 (https://www.researchsquare.com/article/rs-226857/v1). preprint. source
Not checked in the free run.
- May combine two claims. 4
- Classified as probably not a substantial claim. 4
May combine two claims.
Findingown data§ Neutralizing Activity of BNT162b2-Elicited SerumAll serum samples efficiently neutralized USA-WA1/2020 and all viruses carrying variant spikes.
“All the serum samples efficiently neutralized USA-WA1/2020 and all the viruses with variant spikes.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Findingown data§ Neutralizing Activity of BNT162b2-Elicited SerumAll engineered mutant viruses produced infectious viral titers above 10^7 plaque-forming units per milliliter.
“All the mutant viruses yielded infectious viral titers exceeding 107 plaque-forming units per milliliter.”
Quote in the paperNot a substantial claimMay combine two claims.
Findingown data§ Neutralizing Activity of BNT162b2-Elicited SerumThe geometric mean neutralizing titers were 532 for USA-WA1/2020, 663 for B.1.1.7-spike, 437 for P.1-spike, 194 for B.1.351-spike, 485 for B.1.351-∆242-244+D614G, and 331 for B.1.351-RBD+D614G.
“Geometric mean neutralizing titers against USA-WA1/2020, B.1.1.7-spike, P.1-spike, B.1.351-spike, B.1.351-∆242-244+D614G, and B.1.351-RBD+D614G viruses were 532, 663, 437, 194, 485, and 331, respectively (Figure 1 and Table S1).”
Quote in the paperSubstantial claimClassified as probably not a substantial claim.
Study design and conductreasoning§ Neutralizing Activity of BNT162b2-Elicited SerumBecause each assay uses a distinct target virus, comparing neutralizing titers across assays requires caution.
“Therefore, each neutralization assay with a different target virus is unique, and comparisons between neutralization titers from different assays should be interpreted with caution.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Premisecitation§ Neutralizing Activity of BNT162b2-Elicited SerumT-cell immunity may also contribute to protection against SARS-CoV-2.
“T-cell immunity may also be involved in protection,4”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [4] Liao M, Liu Y, Yuan J, et al. Single-cell landscape of bronchoalveolar immune cells in patients with COVID-19. Nat Med 2020; 26: 842- 844. 32398875 source
Not checked in the free run.
May combine two claims.
Interpretationown data§ Neutralizing Activity of BNT162b2-Elicited SerumThe B.1.351 lineage virus was neutralized robustly, with a geometric mean titer well above the level seen after a single BNT162b2 dose, a point at which the C4591001 trial had already shown strong efficacy.
“Neutralizing activity against the B.1.351 lineage virus was robust at a geometric mean titer that was much higher than that obtained after one dose of BNT162b2, when strong efficacy was already observed in the C4591001 efficacy trial.1-3”
Quote in the paperSubstantial claim0 of 3 sources checked- cites [1] Polack FP, Thomas SJ, Kitchin N, et al. Safety and efficacy of the BNT162b2 mRNA Covid-19 vaccine. N Engl J Med 2020; 383: 2603- 2615. 33301246 PMC7745181 source
Not checked in the free run.
- cites [2] Walsh EE, Frenck RW Jr, Falsey AR, et al. Safety and immunogenicity of two RNA-based Covid-19 vaccine candidates. N Engl J Med 2020; 383: 2439- 2450. 33053279 PMC7583697 source
Not checked in the free run.
- cites [3] Sahin U, Muik A, Vogler I, et al. BNT162b2 induces SARS-CoV-2-neutralising antibodies and T cells in humans. December 11, 2020 (https://www.medrxiv.org/content/10.1101/2020.12.09.20245175v1). preprint. source
Not checked in the free run.
- Rests on an assumption: Neutralizing antibody titers are a correlate of vaccine-mediated protection against Covid-19.
- Rests on an assumption: Recombinant viruses carrying the S mutations of a variant lineage faithfully represent the neutralization properties of the authentic variant.
Probably not a substantial claim: may not pass S3 (load-bearing).
Study design and conductnone given§ Neutralizing Activity of BNT162b2-Elicited SerumA study limitation is that mutations might change neutralization through effects on spike function instead of antigenicity.
“Limitations of the study include the potential for mutations to alter neutralization by affecting spike function rather than antigenicity.”
Quote in the paperNot a substantial claimMay combine two claims.
Interpretationown data§ Neutralizing Activity of BNT162b2-Elicited SerumThe B.1.351-spike virus was neutralized robustly but less than USA-WA1/2020.
“Thus, as compared with neutralization of USA-WA1/2020, neutralization of B.1.1.7-spike and P.1-spike viruses was roughly equivalent, and neutralization of B.1.351-spike virus was robust but lower.”
Quote in the paperSubstantial claim
The paper relies on this without support.
Highly transmissible SARS-CoV-2 variants with S-gene mutations are spreading globally.
“New, highly transmissible SARS-CoV-2 variants that were first detected in the United Kingdom (B.1.1.7 lineage), South Africa (B.1.351 lineage), and Brazil (P.1 lineage) with mutations in the S gene are spreading globally.”
The paper relies on this without support.
Neutralizing antibody titers are a correlate of vaccine-mediated protection against Covid-19.
“Neutralizing activity against the B.1.351 lineage virus was robust at a geometric mean titer that was much higher than that obtained after one dose of BNT162b2, when strong efficacy was already observed in the C4591001 efficacy trial.1-3”
The paper relies on this without support.
Recombinant viruses carrying the S mutations of a variant lineage faithfully represent the neutralization properties of the authentic variant.
“To analyze effects on neutralization elicited by BNT162b2, we engineered S mutations from each of the three new lineages into USA-WA1/2020, a relatively early isolate of the virus from January 2020”
The paper relies on this without support.
The 20 serum samples from 15 trial participants are representative of BNT162b2-elicited serum in the vaccinated population.
“We performed 50% plaque reduction neutralization testing (PRNT50) using 20 serum samples that had been obtained from 15 participants in the pivotal trial1,2 2 or 4 weeks after the administration of the second dose of 30 μg of BNT162b2”
Claims other papers make about this one
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Neutralizing activity of mRNA vaccines against B.1.351 was lower by a factor of 8.6 for mRNA-1273 and 6.5 for BNT-162b2 than against D614G, with no difference against B.1.1.7-like mutant.
“Neutralizing activity of the two mRNA vaccines against the B.1.351 variant has also been observed to be lower, by a factor of 8.6 (mRNA-1273 vaccine [Moderna]) or 6.5 (BNT-162b2 vaccine [Pfizer]) on pseudovirus neutralization assay, than activity against the D614G virus, whereas no difference was evident against the N510Y.V1 (B.1.1.7)–like mutant.19,28,29”
From Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant (2021) · cites this paper as [29]
The neutralization data reported here are in line with previous reports.
“The neutralization data reported here are in line with previous reports (42, 47–49).”
From SARS-CoV-2 variants of concern partially escape humoral but not T cell responses in COVID-19 convalescent donors and vaccine recipients (2021) · cites this paper as [47]
Previous studies have demonstrated a similar, less pronounced, decrease in neutralization by polyclonal sera after BNT162b2 vaccination against P.1.
“Although this variant was not investigated in the current study, previous studies have demonstrated a similar, less pronounced, decrease in neutralization by polyclonal sera after BNT162b2 vaccination (47, 77).”
From SARS-CoV-2 variants of concern partially escape humoral but not T cell responses in COVID-19 convalescent donors and vaccine recipients (2021) · cites this paper as [47]
Reduced sensitivity to vaccine-elicited nAbs has been reported for other B.1.351 variants.
“Reduced sensitivity to vaccine-elicited nAbs has been reported for other B.1.351 variants (66, 83, 84).”
From mRNA vaccination boosts cross-variant neutralizing antibodies elicited by SARS-CoV-2 infection (2021) · cites this paper as [83]
Neutralization of a virus bearing changes found in the RBD of B.1.351 and P.1 (E484K + N501Y) was moderately reduced.
“Similarly, neutralization of a virus bearing changes found in the RBD of the B.1.351 and P.1 variants (E484K + N501Y) was moderately reduced (Liu et al., 2021; Wang et al., 2021; Xie et al., 2021), again in keeping with our findings.”
From SARS-CoV-2 variants B.1.351 and P.1 escape from neutralizing antibodies (2021) · cites this paper as Liu et al., 2021
Cells that SARS-CoV-2 infects in the body may display distinct attachment and entry molecules, potentially affecting how particular antibodies block receptor use and entry.
“Indeed, primary cells targeted by SARS-CoV-2 in vivo can express unique sets of attachment and entry factors45, which could impact receptor and entry blockade by specific antibodies.”
From Resistance of SARS-CoV-2 variants to neutralization by monoclonal and serum-derived polyclonal antibodies (2021) · cites this paper as [45]
These results are generally aligned with in vitro neutralization assays showing a large reduction in neutralization against B.1.351 and little to no reduction against B.1.1.7 in fully vaccinated individuals.
“These results are generally aligned with those from in vitro neutralization assays that have shown a large reduction in neutralization against B.1.351,and little to no reduction against B.1.1.7 in fully vaccinated individuals [7][8][9][10][11]17 .”
From Evidence for increased breakthrough rates of SARS-CoV-2 variants of concern in BNT162b2-mRNA-vaccinated individuals (2021) · cites this paper as [7]
BNT162b2 elicits strong antibody responses that effectively neutralize the parental strain and diverse SARS-CoV-2 VOCs.
“and to elicit strong antibody responses, effectively neutralizing the parental strain as well as diverse SARS-CoV-2 VOCs (13–15).”
From Neutralization of SARS-CoV-2 Omicron by BNT162b2 mRNA vaccine–elicited human sera (2022) · cites this paper as [15]
The FDA-approved mRNA vaccines BNT162b2 and mRNA-1273 produce cross-neutralizing antibodies against B.1.351, P.1 and other SARS-CoV-2 variants.
“Fortunately, the FDA-approved mRNA vaccines BNT162b2 and mRNA-1273 produce cross-neutralizing antibodies against B.1.351 and P.1, as well as against other variants, suggesting that they can provide protection against them.”
From mRNA vaccines for infectious diseases: principles, delivery and clinical translation (2021) · cites this paper as [209]
Cross-neutralization efficacies against SARS-CoV-2 variants are significantly lower than against the ancestral variant.
“However, cross-neutralization efficacies have been significantly lower compared with the ancestral variant208–211.”
From mRNA vaccines for infectious diseases: principles, delivery and clinical translation (2021) · cites this paper as [209]
Neutralization activity of sera from both mRNA-1273 and BNT162b2 vaccinated individuals was largely preserved against the B.1.1.7 variant relative to prior variants.
“The neutralization activity of sera collected from both mRNA-1273 and BNT162b2 vaccinated individuals was largely preserved against the B.1.1.7 variant relative to prior variants.”
From The dawn of mRNA vaccines: the COVID-19 case (2021) · cites this paper as [79]
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References 5 · Cited by 537
- Authors
- Liu, Y., Liu, J., Xia, H., Zhang, X., Fontes-Garfias, C. R., Swanson, K. A., Cai, H., Sarkar, R., Chen, W., Cutler, M., Cooper, D., Weaver, S. C., Muik, A., Sahin, U., Jansen, K. U., Xie, X., Dormitzer, P. R., & Shi, P.-Y.
- Affiliations
- The University of Texas Medical Branch at Galveston (US)
- Pfizer (United States) (US)
- BioNTech (Germany) (DE)
- BioNTech, Mainz, Germany
- Corresponding author
- Dormitzer, Philip R.
- ORCID
- Venue
- New England Journal of Medicine
- Publisher
- Massachusetts Medical Society
- Published
- 2021-04-15
- Volume
- 384
- Issue
- 15
- Pages
- 1466-1468
- ISSN
- 0028-4793 (ISSN-L)
- 1533-4406
- PMC
- PMC7944950
- OpenAlex
- W3133327867
- Cited by
- 537
- References
- 5
- Citations by year
- 2026: 5 · 2025: 11 · 2024: 35 · 2023: 43 · 2022: 149 · 2021: 292 · 2020: 2
- FWCI
- 41.17
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- New England Journal of Medicine (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 detection and testing
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › vaccines and immunoinformatics approaches
- Keywords
- BNT162b2, SARS-CoV-2, neutralizing antibodies, serum neutralization, P.1 lineage, B.1.1.7 lineage, SARS-CoV-2 variants, COVID-19 vaccine efficacy
- MeSH terms
- COVID-19, SARS-CoV-2, COVID-19 Vaccines, mRNA Vaccines, BNT162 Vaccine, Antibodies, Viral, Humans, Mutation, Vaccines, Synthetic, Antibodies, Neutralizing, Spike Glycoprotein, Coronavirus
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