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1.
Lancet ; 399(10319): 36-49, 2022 01 01.
Article in English | MEDLINE | ID: covidwho-1557000

ABSTRACT

BACKGROUND: Given the importance of flexible use of different COVID-19 vaccines within the same schedule to facilitate rapid deployment, we studied mixed priming schedules incorporating an adenoviral-vectored vaccine (ChAdOx1 nCoV-19 [ChAd], AstraZeneca), two mRNA vaccines (BNT162b2 [BNT], Pfizer-BioNTech, and mRNA-1273 [m1273], Moderna) and a nanoparticle vaccine containing SARS-CoV-2 spike glycoprotein and Matrix-M adjuvant (NVX-CoV2373 [NVX], Novavax). METHODS: Com-COV2 is a single-blind, randomised, non-inferiority trial in which adults aged 50 years and older, previously immunised with a single dose of ChAd or BNT in the community, were randomly assigned (in random blocks of three and six) within these cohorts in a 1:1:1 ratio to receive a second dose intramuscularly (8-12 weeks after the first dose) with the homologous vaccine, m1273, or NVX. The primary endpoint was the geometric mean ratio (GMR) of serum SARS-CoV-2 anti-spike IgG concentrations measured by ELISA in heterologous versus homologous schedules at 28 days after the second dose, with a non-inferiority criterion of the GMR above 0·63 for the one-sided 98·75% CI. The primary analysis was on the per-protocol population, who were seronegative at baseline. Safety analyses were done for all participants who received a dose of study vaccine. The trial is registered with ISRCTN, number 27841311. FINDINGS: Between April 19 and May 14, 2021, 1072 participants were enrolled at a median of 9·4 weeks after receipt of a single dose of ChAd (n=540, 47% female) or BNT (n=532, 40% female). In ChAd-primed participants, geometric mean concentration (GMC) 28 days after a boost of SARS-CoV-2 anti-spike IgG in recipients of ChAd/m1273 (20 114 ELISA laboratory units [ELU]/mL [95% CI 18 160 to 22 279]) and ChAd/NVX (5597 ELU/mL [4756 to 6586]) was non-inferior to that of ChAd/ChAd recipients (1971 ELU/mL [1718 to 2262]) with a GMR of 10·2 (one-sided 98·75% CI 8·4 to ∞) for ChAd/m1273 and 2·8 (2·2 to ∞) for ChAd/NVX, compared with ChAd/ChAd. In BNT-primed participants, non-inferiority was shown for BNT/m1273 (GMC 22 978 ELU/mL [95% CI 20 597 to 25 636]) but not for BNT/NVX (8874 ELU/mL [7391 to 10 654]), compared with BNT/BNT (16 929 ELU/mL [15 025 to 19 075]) with a GMR of 1·3 (one-sided 98·75% CI 1·1 to ∞) for BNT/m1273 and 0·5 (0·4 to ∞) for BNT/NVX, compared with BNT/BNT; however, NVX still induced an 18-fold rise in GMC 28 days after vaccination. There were 15 serious adverse events, none considered related to immunisation. INTERPRETATION: Heterologous second dosing with m1273, but not NVX, increased transient systemic reactogenicity compared with homologous schedules. Multiple vaccines are appropriate to complete primary immunisation following priming with BNT or ChAd, facilitating rapid vaccine deployment globally and supporting recognition of such schedules for vaccine certification. FUNDING: UK Vaccine Task Force, Coalition for Epidemic Preparedness Innovations (CEPI), and National Institute for Health Research. NVX vaccine was supplied for use in the trial by Novavax.


Subject(s)
/administration & dosage , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , Immunization, Secondary/adverse effects , Immunization, Secondary/methods , Immunogenicity, Vaccine , /administration & dosage , /administration & dosage , Aged , /immunology , COVID-19/prevention & control , COVID-19 Vaccines/immunology , /immunology , Female , Humans , Male , Middle Aged , Single-Blind Method , United Kingdom , Vaccination/adverse effects , Vaccination/methods , /immunology
2.
Lancet ; 398(10303): 856-869, 2021 09 04.
Article in English | MEDLINE | ID: covidwho-1397746

ABSTRACT

BACKGROUND: Use of heterologous prime-boost COVID-19 vaccine schedules could facilitate mass COVID-19 immunisation. However, we have previously reported that heterologous schedules incorporating an adenoviral vectored vaccine (ChAdOx1 nCoV-19, AstraZeneca; hereafter referred to as ChAd) and an mRNA vaccine (BNT162b2, Pfizer-BioNTech; hereafter referred to as BNT) at a 4-week interval are more reactogenic than homologous schedules. Here, we report the safety and immunogenicity of heterologous schedules with the ChAd and BNT vaccines. METHODS: Com-COV is a participant-blinded, randomised, non-inferiority trial evaluating vaccine safety, reactogenicity, and immunogenicity. Adults aged 50 years and older with no or well controlled comorbidities and no previous SARS-CoV-2 infection by laboratory confirmation were eligible and were recruited at eight sites across the UK. The majority of eligible participants were enrolled into the general cohort (28-day or 84-day prime-boost intervals), who were randomly assigned (1:1:1:1:1:1:1:1) to receive ChAd/ChAd, ChAd/BNT, BNT/BNT, or BNT/ChAd, administered at either 28-day or 84-day prime-boost intervals. A small subset of eligible participants (n=100) were enrolled into an immunology cohort, who had additional blood tests to evaluate immune responses; these participants were randomly assigned (1:1:1:1) to the four schedules (28-day interval only). Participants were masked to the vaccine received but not to the prime-boost interval. The primary endpoint was the geometric mean ratio (GMR) of serum SARS-CoV-2 anti-spike IgG concentration (measured by ELISA) at 28 days after boost, when comparing ChAd/BNT with ChAd/ChAd, and BNT/ChAd with BNT/BNT. The heterologous schedules were considered non-inferior to the approved homologous schedules if the lower limit of the one-sided 97·5% CI of the GMR of these comparisons was greater than 0·63. The primary analysis was done in the per-protocol population, who were seronegative at baseline. Safety analyses were done among participants receiving at least one dose of a study vaccine. The trial is registered with ISRCTN, 69254139. FINDINGS: Between Feb 11 and Feb 26, 2021, 830 participants were enrolled and randomised, including 463 participants with a 28-day prime-boost interval, for whom results are reported here. The mean age of participants was 57·8 years (SD 4·7), with 212 (46%) female participants and 117 (25%) from ethnic minorities. At day 28 post boost, the geometric mean concentration of SARS-CoV-2 anti-spike IgG in ChAd/BNT recipients (12 906 ELU/mL) was non-inferior to that in ChAd/ChAd recipients (1392 ELU/mL), with a GMR of 9·2 (one-sided 97·5% CI 7·5 to ∞). In participants primed with BNT, we did not show non-inferiority of the heterologous schedule (BNT/ChAd, 7133 ELU/mL) against the homologous schedule (BNT/BNT, 14 080 ELU/mL), with a GMR of 0·51 (one-sided 97·5% CI 0·43 to ∞). Four serious adverse events occurred across all groups, none of which were considered to be related to immunisation. INTERPRETATION: Despite the BNT/ChAd regimen not meeting non-inferiority criteria, the SARS-CoV-2 anti-spike IgG concentrations of both heterologous schedules were higher than that of a licensed vaccine schedule (ChAd/ChAd) with proven efficacy against COVID-19 disease and hospitalisation. Along with the higher immunogenicity of ChAd/BNT compared with ChAD/ChAd, these data support flexibility in the use of heterologous prime-boost vaccination using ChAd and BNT COVID-19 vaccines. FUNDING: UK Vaccine Task Force and National Institute for Health Research.


Subject(s)
COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , COVID-19/prevention & control , Immunogenicity, Vaccine , Aged , Antibodies, Viral/blood , COVID-19 Vaccines/administration & dosage , Equivalence Trials as Topic , Female , Humans , Immunization Schedule , Immunoglobulin G/blood , Intention to Treat Analysis , Male , Middle Aged , Single-Blind Method , Spike Glycoprotein, Coronavirus/immunology
3.
J Allergy Clin Immunol Pract ; 9(10): 3568-3574, 2021 10.
Article in English | MEDLINE | ID: covidwho-1303568

ABSTRACT

Vaccine hesitancy-defined by the World Health Organization (WHO) as a "delay in acceptance or refusal of vaccines despite availability of vaccination services"-is not a recent phenomenon. Historical records indicate that vaccine hesitancy existed by the 18th century in Europe and even resulted in violent riots. The drivers of vaccine hesitancy have evolved over the last 200 years but not, perhaps, as much as one might expect. More problematic are the means by which concerns over vaccine hesitancy are communicated by a new landscape of digital communication, generating what has been described as an "infodemic" in which an overabundance of information-both factual and misinformation-contributes to hesitancy. In this review, we discuss the background and current drivers of vaccine hesitancy and the evidence base for strategies to combat this. We highlight the important role the allergy/immunology community could have in working to mitigate vaccine hesitancy, particularly with respect to the current coronavirus disease 2019 (COVID-19) pandemic.


Subject(s)
COVID-19 , Hypersensitivity , Vaccines , Humans , SARS-CoV-2 , Vaccination
5.
World Allergy Organ J ; 14(2): 100517, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-1062632

ABSTRACT

Vaccines against COVID-19 (and its emerging variants) are an essential global intervention to control the current pandemic situation. Vaccines often cause adverse events; however, the vast majority of adverse events following immunization (AEFI) are a consequence of the vaccine stimulating a protective immune response, and not allergic in etiology. Anaphylaxis as an AEFI is uncommon, occurring at a rate of less than 1 per million doses for most vaccines. However, within the first days of initiating mass vaccination with the Pfizer-BioNTech COVID-19 vaccine BNT162b2, there were reports of anaphylaxis from the United Kingdom and United States. More recent data imply an incidence of anaphylaxis closer to 1:200,000 doses with respect to the Pfizer-BioNTech vaccine. In this position paper, we discuss the background to reactions to the current COVID-19 vaccines and relevant steps to mitigate against the risk of anaphylaxis as an AEFI. We propose a global surveillance strategy led by allergists in order to understand the potential risk and generate data to inform evidence-based guidance, and thus provide reassurance to public health bodies and members of the public.

6.
J Allergy Clin Immunol Pract ; 9(2): 709-722.e2, 2021 02.
Article in English | MEDLINE | ID: covidwho-949937

ABSTRACT

BACKGROUND: The coronavirus disease 2019 pandemic imposed multiple restrictions on health care services. OBJECTIVE: To investigate the impact of the pandemic on Allergy & Immunology (A&I) services in the United Kingdom. METHODS: A national survey of all A&I services registered with the Royal College of Physicians and/or the British Society for Allergy and Clinical Immunology was carried out. The survey covered staffing, facilities, personal protective equipment, appointments & patient review, investigations, treatments, and research activity. Weeks commencing February 3, 2020 (pre-coronavirus disease), April 6, 2020, and May 8, 2020, were used as reference points for the data set. RESULTS: A total of 99 services participated. There was a reduction in nursing, medical, administrative, and allied health professional staff during the pandemic; 86% and 92% of A&I services continued to accept nonurgent and urgent referrals, respectively, during the pandemic. There were changes in immunoglobulin dose and infusion regimen in 67% and 14% of adult and pediatric services, respectively; 30% discontinued immunoglobulin replacement in some patients. There was a significant (all variables, P ≤ .0001) reduction in the following: face-to-face consultations (increase in telephone consultations), initiation of venom immunotherapy, sublingual and subcutaneous injection immunotherapy, anesthetic allergy testing, and hospital procedures (food challenges, immunoglobulin and omalizumab administration); and a significant increase (P ≤ .0001) in home therapy for immunoglobulin and omalizumab. Adverse clinical outcomes were reported, but none were serious. CONCLUSIONS: The pandemic had a significant impact on A&I services, leading to multiple unplanned pragmatic amendments in service delivery. There is an urgent need for prospective audits and strategic planning in the medium and long-term to achieve equitable, safe, and standardized health care.


Subject(s)
Allergy and Immunology/organization & administration , COVID-19/epidemiology , Delivery of Health Care , Pandemics , Pediatrics/organization & administration , SARS-CoV-2 , Adult , COVID-19/diagnosis , Child , Humans , Hypersensitivity/diagnosis , Hypersensitivity/therapy , State Medicine , Surveys and Questionnaires , United Kingdom
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