Efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine against SARS-CoV-2 variant of concern 202012/01 (B.1.1.7): an exploratory analysis of a randomised controlled trial

Probably not a substantial claim: may not pass S3 (load-bearing).

The majority of cases of non-B.1.1.7 lineage were caused by B.1.177.

“The majority of cases of non-B.1.1.7 lineage were caused by B.1.177 (figure 2).”

Probably not a substantial claim: may not pass S3 (load-bearing).

1466 NAAT positive nose and throat swabs were collected from these participants during the trial.

“1466 NAAT positive nose and throat swabs were collected from these participants during the trial.”

May combine two claims.

219 cases occurred in participants in the primary efficacy cohort and before unblinding, of which 147 were cases of primary symptomatic COVID-19 and 53 were asymptomatic or had unknown symptoms.

“219 of these cases occurred in participants in the primary efficacy cohort and before unblinding, of which 147 were cases of primary symptomatic COVID-19 and 53 were asymptomatic or had unknown symptoms (figure 1).”

May combine two claims.

36 (69%) of 52 cases of primary symptomatic COVID-19 caused by the B.1.1.7 variant occurred in participants who received SD/SD vaccines, and 16 (31%) occurred in participants who received LD/SD vaccines.

“36 (69%) of 52 cases of primary symptomatic COVID-19 caused by the B.1.1.7 variant occurred in participants who received SD/SD vaccines, and 16 (31%) occurred in participants who received LD/SD vaccines.”

• AssumptionRests on an assumption: The sequenced subset of NAAT-positive cases is representative of all NAAT-positive cases with respect to SARS-CoV-2 variant and vaccine group.

May combine two claims.

Primary symptomatic cases remained NAAT positive for longer, with only 56 (21%) of 269 returning only one positive swab.

“However, primary symptomatic cases remained NAAT positive for longer, with only 56 (21%) of 269 returning only one positive swab.”

May combine two claims.

Live-virus microneutralisation antibody titres of sera against B.1.1.7 are lower than against the canonical non-B.1.1.7 strain Victoria; the geometric mean titre is 58 (95% CI 44-77) for B.1.1.7 and 517 (424-631) for Victoria, with a geometric mean ratio (Victoria vs B.1.1.7) of 8.9 (95% CI 7.2-11.0).

“The geometric mean titre is 58 (95% CI 44–77) for B.1.1.7 and 517 (424–631) for Victoria. The geometric mean ratio (Victoria vs B.1.1.7) is 8·9 (95% CI 7·2–11·0).”

May combine two claims.

For primary symptomatic cases for which sequence data were available, 52 (35%) of 147 were due to the B.1.1.7 variant and 95 (65%) were caused by non-B.1.1.7 lineages.

“For primary symptomatic cases for which sequence data were available, 52 (35%) of 147 were due to the B.1.1.7 variant and 95 (65%) were caused by non-B.1.1.7 lineages.”

• AssumptionRests on an assumption: The sequenced subset of NAAT-positive cases is representative of all NAAT-positive cases with respect to SARS-CoV-2 variant and vaccine group.

Probably not a substantial claim: may not pass S3 (load-bearing).

Of these, 401 swabs from 311 participants were successfully sequenced.

“Of these, 401 swabs from 311 participants were successfully sequenced.”

May combine two claims.

Cases of B.1.1.7 first arose in late November, 2020, in trial sites in London and formed an increasing proportion of positive swabs during December, 2020, and January, 2021.

“Cases of B.1.1.7 first arose in late November, 2020, in trial sites in London and formed an increasing proportion of positive swabs during December, 2020, and January, 2021 (figure 3).”

May combine two claims.

The efficacy against asymptomatic infection using sequenced swabs was higher than the previously published estimate of 27% based on NAAT positivity alone, and substantially higher than the efficacy seen in asymptomatic cases that were not sequenced (6%) or for whom no sequencing result could be obtained (−27%).

“It was higher than our previously published estimate of 27%, which was based on NAAT positivity alone,3 and substantially higher than the efficacy seen in the asymptomatic cases that have not been sequenced (6%), or in those for whom no result from sequencing could be obtained (−27%).”

• cites [3] Voysey M Clemens SAC Madhi SA Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK Lancet 397 2021 99 111 33306989 PMC7723445 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In this study, individuals who did not report symptoms had lower viral loads than symptomatic individuals and were NAAT positive for a shorter period of time.

“In our study, individuals who did not report symptoms had lower viral loads than symptomatic individuals and were NAAT positive for a shorter period of time.”

May combine two claims.

There were no cases of hospitalisation or death in these trial participants, so the efficacy of the vaccine on these endpoints cannot be commented on.

“There were no cases of hospitalisation or death in these trial participants, so we cannot comment on the efficacy of the vaccine on these endpoints.”

Probably not a substantial claim: may not pass S3 (load-bearing).

No participants in this study had evidence of the novel E484K spike mutation first described in the B1.351 lineage identified in South Africa.

“No participants in this study had evidence of the novel E484K (Glu484Lys) spike mutation first described in the B1.351 lineage identified in South Africa.”

May combine two claims.

Protection was also shown against non-B.1.1.7 strains, the majority of which were due to the B.1.177 lineage.

“In line with previously published data,3, 46 protection was also shown against the non-B.1.1.7 strains, the majority of which were due to the B.1.177 lineage.”

• cites [3] Voysey M Clemens SAC Madhi SA Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK Lancet 397 2021 99 111 33306989 PMC7723445 sourceNot checked yet

  Not checked in the free run.

• cites [46] Voysey M Costa Clemens SA Madhi SA Single-dose administration and the influence of the timing of the booster dose on immunogenicity and efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine: a pooled analysis of four randomised trials Lancet 397 2021 881 891 33617777 PMC7894131 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Moderna mRNA-1273 vaccine recipients showed similar neutralising activity against VSV and lentivirus pseudoviruses expressing full-length spike protein from either B.1.1.7 or a Wuhan lineage, and this finding was also seen in a live neutralisation assay.

“Sera from recipients of the Moderna mRNA-1273 vaccine showed similar neutralising activity against VSV and lentivirus pseudoviruses expressing full-length spike protein from either B.1.1.7 or a Wuhan lineage,42 and this finding was also seen in a live neutralisation assay.43”

• cites [42] Wu K Werner AP Moliva JI mRNA-1273 vaccine induces neutralizing antibodies against spike mutants from global SARS-CoV-2 variants bioRxiv 2021 published online Jan 25. 10.1101/2021.01.25.427948 (preprint).Not checked yet

  Not checked in the free run.

• cites [43] Edara VV Floyd K Lai L Infection and mRNA-1273 vaccine antibodies neutralize SARS-CoV-2 UK variant medRxiv 2021 published online Feb 5. 10.1101/2021.02.02.21250799 (preprint).Not checked yet

  Not checked in the free run.

Classified as probably not a substantial claim. May combine two claims.

Cases were excluded if they occurred fewer than 15 days after the second dose of vaccine or occurred in participants who were not seronegative on a SARS-CoV-2 N protein assay at baseline.

“Cases were excluded if they occurred fewer than 15 days after the second dose of vaccine or occurred in participants who were not seronegative on a SARS-CoV-2 N protein assay at baseline.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Safety data were reviewed regularly by an independent data safety monitoring board.

“Safety data were reviewed regularly by an independent data safety monitoring board.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

This study is registered with ClinicalTrials.gov, NCT04400838, and ISRCTN, 15281137.

“This study is registered with ClinicalTrials.gov, NCT04400838, and ISRCTN, 15281137.”

May combine two claims.

Further mutations in spike protein observed in other novel lineages appear to be driven by escape of the virus from the neutralising activity of public antibodies, indicating that prevention of transmission might be temporary as the virus adapts to natural or vaccine-induced immunity.

“However, it should be noted that further mutations in spike protein observed in other novel lineages7, 8 appear to be driven by escape of the virus from the neutralising activity of public antibodies,40, 41 indicating that prevention of transmission might be temporary as the virus adapts to natural or vaccine-induced immunity.”

• cites [7] Faria NR Morales Claro I Candido D Genomic characterisation of an emergent SARS-CoV-2 lineage in Manaus: preliminary findings https://virological.org/t/genomic-characterisation-of-an-emergent-sars-cov-2-lineage-in-manaus-preliminary-findings/586 January, 2021Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites [8] Tegally H Wilkinson E Giovanetti M Emergence and rapid spread of a new severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) lineage with multiple spike mutations in South Africa medRxiv 2020 published online Dec 22. 10.1101/2020.12.21.20248640 (preprint). sourceNot checked yet

  Not checked in the free run.

• cites [40] Wibmer CK Ayres F Hermanus T SARS-CoV-2 501Y.V2 escapes neutralization by South African COVID-19 donor plasma bioRxiv 2021 published online Jan 19. 10.1101/2021.01.18.427166 (preprint). 33654292 sourceNot checked yet

  Not checked in the free run.

• cites [41] Wang P Liu L Iketani S Increased resistance of SARS-CoV-2 variants B.1.351 and B.1.1.7 to antibody neutralization bioRxiv 2021 published online Jan 26. 10.1101/2021.01.25.428137 (preprint). sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

COV002 is a single-blind, multicentre, randomised phase 2/3 trial assessing the safety and efficacy of the ChAdOx1 nCoV-19 vaccine.

“COV002 is a single-blind, multicentre, randomised phase 2/3 trial assessing the safety and efficacy of the ChAdOx1 nCoV-19 vaccine.”

Classified as probably not a substantial claim.

Participants were randomly assigned in a 1:1 ratio to receive standard-dose ChAdOx1 nCoV-19 vaccine or a meningococcal group A, C, W, and Y conjugate vaccine (MenACWY) as control.

“Participants were randomly assigned in a 1:1 ratio to receive standard-dose ChAdOx1 nCoV-19 vaccine (5 × 1010 viral particles) or a meningococcal group A, C, W, and Y conjugate vaccine (MenACWY) as control.”

May combine two claims.

Baseline demographics in individuals with the B.1.1.7 variant were similar to those with non-B.1.1.7 variants, as were their prime-boost intervals.

“Baseline demographics in individuals with the B.1.1.7 variant were similar to those with non-B.1.1.7 variants, as were their prime-boost intervals (appendix pp 2–4).”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

B.1.1.7 has accrued 23 mutations across the genome, including N501Y, 69-70del, and P681H.

“B.1.1.7 has accrued 23 mutations across the genome, including a non-synonymous mutation affecting the spike protein, N501Y (Asn501Tyr), which might increase ACE2 receptor binding affinity,10 the spike deletion 69–70del associated with viral escape in immunocompromised individuals,9 and the non-synonymous mutation P681H (Pro681His) affecting the furin cleavage site between the S1 and S2 subunits of”

• cites [9] Rambaut A Loman N Pybus O Preliminary genomic characterisation of an emergent SARS-CoV-2 lineage in the UK defined by a novel set of spike mutations https://virological.org/t/preliminary-genomic-characterisation-of-an-emergent-sars-cov-2-lineage-in-the-uk-defined-by-a-novel-set-of-spike-mutations/563 December, 2020Not checked yet

  Not checked in the free run.

• cites [10] Starr TN Greaney AJ Hilton SK Deep mutational scanning of SARS-CoV-2 receptor binding domain reveals constraints on folding and ACE2 binding Cell 182 2020 1295 310.e20 32841599 PMC7418704Not checked yet

  Not checked in the free run.

• cites [11] Kemp SA Datir RP Collier DA Recurrent emergence and transmission of a SARS-CoV-2 spike deletion ΔH69/V70 bioRxiv 2020 published online Dec 15. 10.1101/2020.12.14.422555 (preprint).Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

The B.1.1.7 variant in the UK arose while there was a low level of population immunity from natural infection and before vaccine programmes had begun, so the variant is likely to have been selected for improved ACE2 receptor binding and transmissibility, rather than as a result of vaccine-induced immunity.

“The B.1.1.7 variant in the UK arose while there was a low level of population immunity from natural infection and before vaccine programmes had begun, so the variant is likely to have been selected for improved ACE2 receptor binding and transmissibility, rather than as a result of vaccine-induced immunity.”

May combine two claims.

ChAdOx1 nCoV-19 was efficacious against both the B.1.1.7 variant and non-B.1.1.7 variants.

“ChAdOx1 nCoV-19 was efficacious against both the B.1.1.7 variant and non-B.1.1.7 variants.”

• AssumptionRests on an assumption: The meningococcal group A, C, W, and Y conjugate vaccine (MenACWY) used as control does not affect SARS-CoV-2 infection or COVID-19 disease.
• AssumptionRests on an assumption: The sequenced subset of NAAT-positive cases is representative of all NAAT-positive cases with respect to SARS-CoV-2 variant and vaccine group.

Probably not a substantial claim: may not pass S3 (load-bearing).

All samples were processed by laboratory staff who were masked to vaccine allocation.

“All samples were processed by laboratory staff who were masked to vaccine allocation.”

May combine two claims.

Lower neutralising antibody titres are sufficient to provide protection, or other mechanisms of immunity could be responsible for protection from disease in vaccinated individuals.

“These findings suggest either that lower neutralising antibody titres are sufficient to provide protection or that other mechanisms of immunity could be responsible for protection from disease in vaccinated individuals.”

Probably not a substantial claim: may not pass S4 (based).

A new variant of SARS-CoV-2, B.1.1.7, emerged as the dominant cause of COVID-19 disease in the UK from November, 2020.

“A new variant of SARS-CoV-2, B.1.1.7, emerged as the dominant cause of COVID-19 disease in the UK from November, 2020.”

Probably not a substantial claim: may not pass S3 (load-bearing).

All endpoints were reviewed for inclusion by an independent, blinded adjudication committee.

“All endpoints were reviewed for inclusion by an independent, blinded adjudication committee.”

May combine two claims.

Vaccination reduced viral load and length of NAAT positivity against both B.1.1.7 and non-B.1.1.7 lineages.

“Furthermore, vaccination reduced viral load and length of NAAT positivity against both B.1.1.7 and non-B.1.1.7 lineages.”

• AssumptionRests on an assumption: The meningococcal group A, C, W, and Y conjugate vaccine (MenACWY) used as control does not affect SARS-CoV-2 infection or COVID-19 disease.

Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based). May combine two claims.

As an increasing proportion of the population is vaccinated, selection of mutations that allow immune evasion may occur, requiring revaccination with antigens derived from the new lineages.

“As an increasing proportion of the population is vaccinated, selection of mutations that allow immune evasion may occur, requiring revaccination with antigens derived from the new lineages.”

May combine two claims.

The number of samples available for analysis was not sufficient to power a study to determine whether there was a small difference in efficacy between the B.1.1.7 and non-B.1.1.7 variants; therefore, an 11% reduction in efficacy cannot be ruled out.

“The number of samples available for analysis was not sufficient to power a study to determine whether there was a small difference in efficacy between the B.1.1.7 and non-B.1.1.7 variants; therefore, we cannot rule out an 11% reduction in efficacy.”

Classified as probably not a substantial claim. May combine two claims.

Assuming a low false-positive rate of 0.1%, this equates to 200 false-positive swabs, which could skew an attempt to estimate vaccine efficacy.

“Assuming a low false-positive rate of 0·1%, this equates to 200 false-positive swabs, which could skew an attempt to estimate vaccine efficacy.”

• AssumptionThe authors state this as an assumption: The false-positive rate in the community testing is 0.1%.

May combine two claims.

The false-positive rate within Lighthouse Laboratories used for community testing is unknown, although early estimates based on other historical RNA viral RT-PCR testing suggested rates of 0.8-4.0%.

“The false-positive rate within Lighthouse Laboratories used for the community testing is unknown, although early estimates based on other historical RNA viral RT-PCR testing suggested rates of 0·8–4·0%.53”

• cites [53] Mayers C Baker K Impact of false-positives and false-negatives in the UK's COVID-19 RT-PCR testing programme https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/895843/S0519_Impact_of_false_positives_and_negatives.pdf June 3, 2020Not checked yet

  Not checked in the free run.

May combine two claims.

ChAdOx1 nCoV-19 elicits robust antibody-dependent monocyte phagocytosis, antibody-dependent neutrophil phagocytosis activity, and antibody-dependent natural killer cell activation after two doses of vaccine, at similar levels to those seen in convalescent sera.

“We have previously shown that ChAdOx1 nCoV-19 elicits robust antibody-dependent monocyte phagocytosis, antibody-dependent neutrophil phagocytosis activity, and antibody-dependent natural killer cell activation after two doses of vaccine,29 at similar levels to those seen in convalescent sera.”

• cites [29] Barrett JR Belij-Rammerstorfer S Dold C Phase 1/2 trial of SARS-CoV-2 vaccine ChAdOx1 nCoV-19 with a booster dose induces multifunctional antibody responses Nat Med 27 2021 279 288 33335322 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

Different immune mechanisms could also be responsible for the protection afforded by ChAdOx1 nCoV-19.

“Different immune mechanisms could also be responsible for the protection afforded by ChAdOx1 nCoV-19.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Early national vaccine effectiveness data has shown that a single dose of ChAdOx1 nCoV-19 confers protection from both symptomatic disease and COVID-19-related hospitalisation.

“Early national vaccine effectiveness data has shown that a single dose of ChAdOx1 nCoV-19 confers protection from both symptomatic disease and COVID-19-related hospitalisation,47 consistent with the findings presented here.”

• cites [47] Lopez Bernal J Andrews A Gower C Early effectiveness of COVID-19 vaccination with BNT162b2 mRNA vaccine and ChAdOx1 adenovirus vector vaccine on symptomatic disease, hospitalisations and mortality in older adults in England medRxiv 2021 published online March 2. 10.1101/2021.03.01.21252652 (preprint).Not checked yet

  Not checked in the free run.

Classified as probably not a substantial claim.

T-cell responses are associated with recovery from clinical COVID-19 disease.

“T-cell responses are associated with recovery from clinical COVID-19 disease52”

• cites [52] Peng Y Mentzer AJ Liu G Broad and strong memory CD4+ and CD8+ T cells induced by SARS-CoV-2 in UK convalescent individuals following COVID-19 Nat Immunol 21 2020 1336 1345 32887977 PMC7611020Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Human error in the receiving and sequencing laboratories and missteps in quality control of data matching between laboratories could have affected data veracity, but in most cases multiple swabs from the same individual over weeks allowed corroboration of in-host minor variants and provided certainty of sequence linkage to a given participant.

“Although human error in the receiving and sequencing laboratories and missteps in quality control of data matching between laboratories could have affected data veracity, in most cases multiple swabs were obtained from the same individual over a period of weeks, allowing corroboration of in-host minor variants, and providing certainty of sequence linkage to a given participant.”

May combine two claims.

Antibody-dependent complement deposition and antibody-dependent natural killer cell activation are associated with protection from challenge in animal models.

“Antibody-dependent complement deposition and antibody-dependent natural killer cell activation are associated with protection from challenge in animal models.51”

• cites [51] Mercado NB Zahn R Wegmann F Single-shot Ad26 vaccine protects against SARS-CoV-2 in rhesus macaques Nature 586 2020 583 588 32731257 PMC7581548 sourceNot checked yet

  Not checked in the free run.

Classified as probably not a substantial claim. May combine two claims.

Only genomes that had no evidence of contamination were included in this analysis, with sequences showing evidence of mixed variant calls at multiple lineage-defining sites manually excluded.

“Only genomes that had no evidence of contamination were included in this analysis, with sequences showing evidence of mixed variant calls at multiple lineage-defining sites being manually excluded.”

Probably not a substantial claim: may not pass S2 (checkable).

These observations provide strong support for mass vaccination as a tool to control pandemic coronavirus, when the vaccine is reasonably well matched to the circulating variant.

“These observations provide strong support for mass vaccination as a tool to control pandemic coronavirus, when the vaccine is reasonably well matched to the circulating variant.”

Classified as probably not a substantial claim.

It is possible that some specimens which could not be sequenced were false-positive samples generated by low-level plate contamination or amplicon contamination in the NAAT assay.

“It is possible that some of the specimens which could not be sequenced were false-positive samples generated by low-level plate contamination or amplicon contamination in the NAAT assay.”

Probably not a substantial claim: may not pass S3 (load-bearing).

ChAdOx1 nCoV-19 generates spike-specific T cells that peak at 14 days after priming vaccination.

“we have previously reported that ChAdOx1 nCoV-19 generates spike-specific T cells that peak at 14 days after priming vaccination.34”

• cites [34] Ramasamy MN Minassian AM Ewer KJ Safety and immunogenicity of ChAdOx1 nCoV-19 vaccine administered in a prime-boost regimen in young and old adults (COV002): a single-blind, randomised, controlled, phase 2/3 trial Lancet 396 2021 1979 1993 33220855 PMC7674972 sourceNot checked yet

  Not checked in the free run.

Classified as probably not a substantial claim.

Preclinical COVID-19 vaccine studies suggest that the development of neutralising antibody is associated with protection from subsequent challenge with live virus.

“Preclinical COVID-19 vaccine studies suggest that the development of neutralising antibody is associated with protection from subsequent challenge with live virus.50”

• cites [50] van Doremalen N Lambe T Spencer A ChAdOx1 nCoV-19 vaccine prevents SARS-CoV-2 pneumonia in rhesus macaques Nature 586 2020 578 582 32731258 PMC8436420 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Previous studies have shown no difference in viral load between symptomatic and asymptomatic individuals.

“Previous studies have shown no difference in viral load between symptomatic and asymptomatic individuals.54, 57”

• cites [54] Singanayagam A Patel M Charlett A Duration of infectiousness and correlation with RT-PCR cycle threshold values in cases of COVID-19, England, January to May 2020 Euro Surveill 25 2020 2001483 PMC7427302 32794447Not checked yet

  Not checked in the free run.

• cites [57] Walsh KA Spillane S Comber L The duration of infectiousness of individuals infected with SARS-CoV-2 J Infect 81 2020 847 856 33049331 PMC7547320Not checked yet

  Not checked in the free run.

May combine two claims.

The higher estimate of efficacy against asymptomatic infection in this study from sequenced swabs is less likely to be affected by false-positive results and therefore might be more reliable.

“The higher estimate of efficacy against asymptomatic infection in this study from sequenced swabs is less likely to be affected by false-positive results and therefore might be more reliable.”

Probably not a substantial claim: may not pass S3 (load-bearing).

The E484K mutation appears to result in a lower neutralising ability of mRNA vaccine sera.

“The E484K mutation appears to result in a lower neutralising ability of mRNA vaccine sera.48”

• cites [48] Tada T Dcosta BM Samanovic-Golden M Neutralization of viruses with European, South African, and United States SARS-CoV-2 variant spike proteins by convalescent sera and BNT162b2 mRNA vaccine-elicited antibodies bioRxiv 2021 published online Feb 7. 10.1101/2021.02.05.430003 (preprint). sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Antibodies mediating these functions could have complementarity determining regions that recognise and bind to alternative conformational epitopes on spike protein to those bound by neutralising antibodies, explaining the observed clinical efficacy against B.1.1.7.

“Antibodies mediating these functions could have complementarity determining regions that recognise and bind to alternative conformational epitopes on spike protein to those bound by neutralising antibodies, explaining the observed clinical efficacy against B.1.1.7.”

Probably not a substantial claim: may not pass S3 (load-bearing).

The sample size for this analysis was determined by sequence availability.

“The sample size for this analysis was determined by sequence availability.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The sequences obtained for this study were generated by multiple sequencing laboratories affiliated with the COVID-19 Genomics UK Consortium, using local infrastructure for library preparation and sequencing, with independent quality control procedures performed at each sequencing site and centrally within COVID-19 Genomics UK.

“The sequences obtained for this study were generated by multiple sequencing laboratories affiliated with the COVID-19 Genomics UK Consortium, using local infrastructure for library preparation and sequencing, with independent quality control procedures performed at each sequencing site and centrally within COVID-19 Genomics UK.”

May combine two claims.

Despite the large reduction in measured live neutralising activity against B.1.1.7, the vaccine provided strong protection against B.1.1.7 variant disease, with the lower bound of the 95% CI above the 30% threshold recommended by WHO.

“Despite the large reduction in measured live neutralising activity against B.1.1.7 virus, the vaccine provided strong protection against B.1.1.7 variant disease, with the lower bound of the 95% CI above the 30% threshold recommended by WHO.45”

• cites [45] WHO WHO R&D Blueprint: an international randomised trial of candidate vaccines against COVID-19 https://www.who.int/blueprint/priority-diseases/key-action/WHOCOVID-2019_SolidarityVaccineTrial_ExpandedOutline_19April_Web.pdf?ua=1 April 19, 2020Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Anti-ChAdOx1 vector antibodies do not affect anti-spike antibody responses or spike-specific T-cell responses.

“We have previously shown that anti-ChAdOx1 vector antibodies do not affect anti-spike antibody responses or spike-specific T-cell responses.34”

• cites [34] Ramasamy MN Minassian AM Ewer KJ Safety and immunogenicity of ChAdOx1 nCoV-19 vaccine administered in a prime-boost regimen in young and old adults (COV002): a single-blind, randomised, controlled, phase 2/3 trial Lancet 396 2021 1979 1993 33220855 PMC7674972 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Inflated efficacy against asymptomatic infection could also be caused by lower viral loads in true-positive samples from vaccine recipients, making sequencing more difficult for these samples, thereby lowering the counts in the vaccine group and inflating vaccine efficacy for asymptomatic infections.

“However, inflated efficacy against asymptomatic infection could also be caused by lower viral loads in true-positive samples from vaccine recipients, making sequencing more difficult for these samples, thereby lowering the counts in the vaccine group of the study and inflating vaccine efficacy for asymptomatic infections.”

Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

The emergence of new lineages of SARS-CoV-2 due to viral mutation and immune and fitness selection is inevitable.

“The emergence of new lineages of SARS-CoV-2 due to viral mutation and immune and fitness selection is inevitable.”

May combine two claims.

Samples with a high Ct value (>30) were not routinely sequenced by several COVID-19 Genomics UK laboratories, limiting the ability to assess the lineage of low viral load specimens, which were over-represented in asymptomatic participants.

“Furthermore, samples with a high Ct value (>30) were not routinely sequenced by several COVID-19 Genomics UK laboratories, thus limiting our ability to assess the lineage of low viral load specimens, which were over-represented in asymptomatic participants.”