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1.
Am J Obstet Gynecol ; 226(4): 459-474, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1670128

ABSTRACT

Maternal vaccination is an effective means of protecting pregnant women, their fetuses, and infants from vaccine-preventable infections. Despite the availability of sufficient safety data to support the use of vaccines during pregnancy, maternal immunization remains an underutilized method of disease prevention, often because of concerns from both healthcare providers and pregnant women about vaccine safety. Such concerns have been reflected in the low uptake of the COVID-19 vaccine among pregnant women seen in many parts of the world. Here, we present an update of the current recommendations for the use of vaccines during pregnancy, including the evidence supporting the use of novel vaccine platforms. We also provide an overview of the data supporting the use of COVID-19 vaccines in pregnancy and an update of the status of vaccines that are currently under development for use in pregnant women.


Subject(s)
COVID-19 , Influenza Vaccines , COVID-19/prevention & control , COVID-19 Vaccines , Female , Humans , Infant , Pregnancy , Pregnant Women , Vaccination
2.
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
3.
Lancet Respir Med ; 10(2): 167-179, 2022 02.
Article in English | MEDLINE | ID: covidwho-1517541

ABSTRACT

BACKGROUND: The safety and immunogenicity profile of COVID-19 vaccines when administered concomitantly with seasonal influenza vaccines have not yet been reported. We therefore aimed to report the results of a substudy within a phase 3 UK trial, by evaluating the safety, immunogenicity, and efficacy of NVX-CoV2373 when co-administered with licensed seasonal influenza vaccines. METHODS: We did a planned exploratory substudy as part of the randomised, observer-blinded, placebo-controlled, phase 3 trial of the safety and efficacy of the COVID-19 vaccine (NVX-CoV2373) by co-administrating the influenza vaccine at four study hospitals in the UK. Approximately, the first 400 participants meeting the main study entry criteria-with no contraindications to influenza vaccination-were invited to join the substudy. Participants of the main study were randomly assigned (1:1) to receive two intramuscular injections of either NVX-CoV2373 (5 µg) or placebo (normal saline) 21 days apart; participants enrolled into the substudy were co-vaccinated with a single (0·5 mL) intramuscular, age-appropriate (quadrivalent influenza cell-based vaccine [Flucelvax Quadrivalent; Seqirus UK, Maidenhead] for those aged 18-64 years and adjuvanted trivalent influenza vaccine [Fluad; Seqirus UK, Maidenhead] for those ≥65 years), licensed, influenza vaccine on the opposite deltoid to that of the first study vaccine dose or placebo. The influenza vaccine was administered in an open-label manner and at the same time as the first study injection. Reactogenicity was evaluated via an electronic diary for 7 days after vaccination in addition to monitoring for unsolicited adverse events, medically attended adverse events, and serious adverse events. Immunogenicity was assessed with influenza haemagglutination inhibition and SARS-CoV-2 anti-spike protein IgG assays. Vaccine efficacy against PCR-confirmed, symptomatic COVID-19 was assessed in participants who were seronegative at baseline, received both doses of study vaccine or placebo, had no major protocol deviations affecting the primary endpoint, and had no confirmed cases of symptomatic COVID-19 from the first dose until 6 days after the second dose (per-protocol efficacy population). Immunogenicity was assessed in participants who received scheduled two doses of study vaccine, had a baseline sample and at least one post-vaccination sample, and had no major protocol violations before unmasking (per-protocol immunogenicity population). Reactogenicity was analysed in all participants who received at least one dose of NVX-CoV2373 or placebo and had data collected for reactogenicity events. Safety was analysed in all participants who received at least one dose of NVX-CoV2373 or placebo. Comparisons were made between participants of the substudy and the main study (who were not co-vaccinated for influenza). This study is registered with ClinicalTrials.gov, number NCT04583995. FINDINGS: Between Sept 28, 2020, and Nov 28, 2020, a total of 15 187 participants were randomised into the main phase 3 trial, of whom 15 139 received treatment (7569 received dose one of NVX-CoV2373 and 7570 received dose one of placebo). 431 participants were co-vaccinated with a seasonal influenza vaccine in the substudy (217 received NVX-CoV2373 plus the influenza vaccine and 214 received placebo plus the influenza vaccine). In general, the substudy participants were younger, more racially diverse, and had fewer comorbid conditions than those in the main study. Reactogenicity events were more common in the co-administration group than in the NVX-CoV2373 alone group: tenderness (113 [64·9%] of 174 vs 592 [53·3%] of 1111) or pain (69 [39·7%] vs 325 [29·3%]) at injection site, fatigue (48 [27·7%] vs 215 [19·4%]), and muscle pain (49 [28·3%] vs 237 [21·4%]). Incidences of unsolicited adverse events, treatment-related medically attended adverse events, and serious adverse events were low and balanced between the co-administration group and the NVX-CoV2373 alone group. No episodes of anaphylaxis or deaths were reported within the substudy. Co-administration resulted in no change to influenza vaccine immune response although a reduction in antibody responses to the NVX-CoV2373 vaccine was noted. NVX-CoV2373 vaccine efficacy in the substudy (ie, participants aged 18 to <65 years) was 87·5% (95% CI -0·2 to 98·4) and in the main study was 89·8% (95% CI 79·7-95·5). INTERPRETATION: To our knowledge, this substudy is the first to show the safety, immunogenicity, and efficacy profile of a COVID-19 vaccine when co-administered with seasonal influenza vaccines. Our results suggest concomitant vaccination might be a viable immunisation strategy. FUNDING: Novavax.


Subject(s)
COVID-19 , Influenza Vaccines , Adolescent , Adult , Aged , COVID-19 Vaccines , Double-Blind Method , Humans , Immunogenicity, Vaccine , Influenza Vaccines/adverse effects , Middle Aged , SARS-CoV-2 , Seasons , Young Adult
4.
Clin Transl Sci ; 15(2): 524-534, 2022 02.
Article in English | MEDLINE | ID: covidwho-1476158

ABSTRACT

The safety of novel therapeutics and vaccines are typically assessed in early phase clinical trials involving "healthy volunteers." Abnormalities in such individuals can be difficult to interpret and may indicate previously unrecognized medical conditions. The frequency of incidental findings (IFs) in healthy volunteers who attend for clinical trial screening is unclear. To assess this, we retrospectively analyzed data for 1838 "healthy volunteers" screened for enrolment in a UK multicenter, phase I/II severe acute respiratory syndrome-coronavirus 2 (SARS-COV-2) vaccine trial. Participants were predominantly White (89.7%, 1640/1828) with a median age of 34 years (interquartile range [IQR] = 27-44). There were 27.7% of participants (510/1838) who had at least one IF detected. The likelihood of identifying evidence of a potential, new blood-borne virus infection was low (1 in 238 participants) compared with identification of an elevated alanine transaminase (ALT; 1 in 17 participants). A large proportion of participants described social habits that could impact negatively on their health; 21% consumed alcohol in excess, 10% were current smokers, 11% described recreational drug use, and only 48% had body weight in the ideal range. Our data demonstrate that screening prior to enrollment in early phase clinical trials identifies a range of IFs, which should inform discussion during the consent process. Greater clarity is needed to ensure an appropriate balance is struck between early identification of medical problems and avoidance of exclusion of volunteers due to spurious or physiological abnormalities. Debate should inform the role of the trial physician in highlighting and advising about unhealthy social habits.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , Incidental Findings , SARS-CoV-2/immunology , Adult , Alanine Transaminase/blood , Body Mass Index , Female , Healthy Volunteers , Humans , Male , Retrospective Studies
5.
Pediatr Infect Dis J ; 40(12): e472-e474, 2021 12 01.
Article in English | MEDLINE | ID: covidwho-1447657

ABSTRACT

We present a case of a 17-year-old boy with X-linked agammaglobulinemia who had mild disease when initially infected with SARS-CoV-2 but after recovering from acute infection developed fevers and a raised erythrocyte sedimentation rate that persisted for several weeks without any ongoing respiratory symptoms. Multiple nasopharyngeal swabs were found to be negative for SARS-CoV-2 during the febrile period, but typical changes of COVID-19 on high resolution CT chest scan led to the detection of SARS-CoV-2 on RT-PCR in a sample from a bronchoalveolar lavage. His fevers completely resolved after a 5-day course of remdesivir.


Subject(s)
Agammaglobulinemia/complications , COVID-19/complications , Genetic Diseases, X-Linked/complications , Pneumonia, Viral/virology , SARS-CoV-2 , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/therapeutic use , Adolescent , Alanine/analogs & derivatives , Alanine/therapeutic use , Antibodies, Viral/blood , Antiviral Agents/therapeutic use , Biomarkers/blood , Bronchoalveolar Lavage Fluid/virology , COVID-19/drug therapy , Fever , Humans , Inflammation/blood , Inflammation/metabolism , Male , Pneumonia, Viral/drug therapy , Pneumonia, Viral/pathology , SARS-CoV-2/isolation & purification
6.
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
7.
Am J Obstet Gynecol ; 226(2): 236.e1-236.e14, 2022 02.
Article in English | MEDLINE | ID: covidwho-1347471

ABSTRACT

BACKGROUND: Concerns have been raised regarding a potential surge of COVID-19 in pregnancy, secondary to the rising numbers of COVID-19 in the community, easing of societal restrictions, and vaccine hesitancy. Although COVID-19 vaccination is now offered to all pregnant women in the United Kingdom; limited data exist on its uptake and safety. OBJECTIVE: This study aimed to investigate the uptake and safety of COVID-19 vaccination among pregnant women. STUDY DESIGN: This was a cohort study of pregnant women who gave birth at St George's University Hospitals National Health Service Foundation Trust, London, United Kingdom, between March 1, 2020, and July 4, 2021. The primary outcome was uptake of COVID-19 vaccination and its determinants. The secondary outcomes were perinatal safety outcomes. Data were collected on COVID-19 vaccination uptake, vaccination type, gestational age at vaccination, and maternal characteristics, including age, parity, ethnicity, index of multiple deprivation score, and comorbidities. Further data were collected on perinatal outcomes, including stillbirth (fetal death at ≥24 weeks' gestation), preterm birth, fetal and congenital abnormalities, and intrapartum complications. Pregnancy and neonatal outcomes of women who received the vaccine were compared with that of a matched cohort of women with balanced propensity scores. Effect magnitudes of vaccination on perinatal outcomes were reported as mean differences or odds ratios with 95% confidence intervals. Factors associated with antenatal vaccination were assessed with logistic regression analysis. RESULTS: Data were available for 1328 pregnant women of whom 140 received at least 1 dose of the COVID-19 vaccine before giving birth and 1188 women who did not; 85.7% of those vaccinated received their vaccine in the third trimester of pregnancy and 14.3% in the second trimester of pregnancy. Of those vaccinated, 127 (90.7%) received a messenger RNA vaccine and 13 (9.3%) a viral vector vaccine. There was evidence of reduced vaccine uptake in younger women (P=.001), women with high levels of deprivation (ie, fifth quintile of the index of multiple deprivation; P=.008), and women of Afro-Caribbean or Asian ethnicity compared with women of White ethnicity (P<.001). Women with prepregnancy diabetes mellitus had increased vaccine uptake (P=.008). In the multivariable model the fifth deprivation quintile (most deprived) (adjusted odds ratio, 0.10; 95% confidence interval, 0.02-0.10; P=.003) and Afro-Caribbean ethnicity (adjusted odds ratio, 0.27; 95% confidence interval, 0.06-0.85; P=.044) were significantly associated with lower antenatal vaccine uptake, whereas prepregnancy diabetes mellitus was significantly associated with higher antenatal vaccine uptake (adjusted odds ratio, 10.5; 95% confidence interval, 1.74-83.2; P=.014). In a propensity score-matched cohort, the rates of adverse pregnancy outcomes of 133 women who received at least 1 dose of the COVID-19 vaccine in pregnancy were similar to that of unvaccinated pregnant women (P>.05 for all): stillbirth (0.0% vs 0.2%), fetal abnormalities (2.2% vs 2.5%), postpartum hemorrhage (9.8% vs 9.0%), cesarean delivery (30.8% vs 34.1%), small for gestational age (12.0% vs 12.8%), maternal high-dependency unit or intensive care admission (6.0% vs 4.0%), or neonatal intensive care unit admission (5.3% vs 5.0%). Intrapartum pyrexia (3.7% vs 1.0%; P=.046) was significantly increased but the borderline statistical significance was lost after excluding women with antenatal COVID-19 infection (P=.079). Mixed-effects Cox regression showed that vaccination was not significantly associated with birth at <40 weeks' gestation (hazard ratio, 0.93; 95% confidence interval, 0.71-1.23; P=.624). CONCLUSION: Of pregnant women eligible for COVID-19 vaccination, less than one-third accepted COVID-19 vaccination during pregnancy, and they experienced similar pregnancy outcomes with unvaccinated pregnant women. There was lower uptake among younger women, non-White ethnicity, and lower socioeconomic background. This study has contributed to the body of evidence that having COVID-19 vaccination in pregnancy does not alter perinatal outcomes. Clear communication to improve awareness among pregnant women and healthcare professionals on vaccine safety is needed, alongside strategies to address vaccine hesitancy. These strategies include postvaccination surveillance to gather further data on pregnancy outcomes, particularly after first-trimester vaccination, and long-term infant follow-up.


Subject(s)
COVID-19 Vaccines/therapeutic use , COVID-19/prevention & control , Pregnancy Complications, Infectious/prevention & control , Vaccination Coverage/statistics & numerical data , /therapeutic use , Adult , Age Factors , Caribbean Region , Case-Control Studies , Cesarean Section/statistics & numerical data , Congenital Abnormalities/epidemiology , Female , Fever/epidemiology , Humans , Infant, Small for Gestational Age , Intensive Care Units , Intensive Care Units, Neonatal , Logistic Models , Obstetric Labor Complications/epidemiology , Postpartum Hemorrhage/epidemiology , Pregnancy , Premature Birth/epidemiology , Propensity Score , Proportional Hazards Models , SARS-CoV-2 , Social Determinants of Health , Stillbirth/epidemiology , United Kingdom/epidemiology
8.
N Engl J Med ; 385(13): 1172-1183, 2021 09 23.
Article in English | MEDLINE | ID: covidwho-1287849

ABSTRACT

BACKGROUND: Early clinical data from studies of the NVX-CoV2373 vaccine (Novavax), a recombinant nanoparticle vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that contains the full-length spike glycoprotein of the prototype strain plus Matrix-M adjuvant, showed that the vaccine was safe and associated with a robust immune response in healthy adult participants. Additional data were needed regarding the efficacy, immunogenicity, and safety of this vaccine in a larger population. METHODS: In this phase 3, randomized, observer-blinded, placebo-controlled trial conducted at 33 sites in the United Kingdom, we assigned adults between the ages of 18 and 84 years in a 1:1 ratio to receive two intramuscular 5-µg doses of NVX-CoV2373 or placebo administered 21 days apart. The primary efficacy end point was virologically confirmed mild, moderate, or severe SARS-CoV-2 infection with an onset at least 7 days after the second injection in participants who were serologically negative at baseline. RESULTS: A total of 15,187 participants underwent randomization, and 14,039 were included in the per-protocol efficacy population. Of the participants, 27.9% were 65 years of age or older, and 44.6% had coexisting illnesses. Infections were reported in 10 participants in the vaccine group and in 96 in the placebo group, with a symptom onset of at least 7 days after the second injection, for a vaccine efficacy of 89.7% (95% confidence interval [CI], 80.2 to 94.6). No hospitalizations or deaths were reported among the 10 cases in the vaccine group. Five cases of severe infection were reported, all of which were in the placebo group. A post hoc analysis showed an efficacy of 86.3% (95% CI, 71.3 to 93.5) against the B.1.1.7 (or alpha) variant and 96.4% (95% CI, 73.8 to 99.5) against non-B.1.1.7 variants. Reactogenicity was generally mild and transient. The incidence of serious adverse events was low and similar in the two groups. CONCLUSIONS: A two-dose regimen of the NVX-CoV2373 vaccine administered to adult participants conferred 89.7% protection against SARS-CoV-2 infection and showed high efficacy against the B.1.1.7 variant. (Funded by Novavax; EudraCT number, 2020-004123-16.).


Subject(s)
COVID-19 Vaccines , COVID-19/prevention & control , Immunogenicity, Vaccine , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/epidemiology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/immunology , Humans , Injections, Intramuscular/adverse effects , Middle Aged , SARS-CoV-2 , Single-Blind Method , Vaccines, Synthetic/immunology , Young Adult
10.
Lancet ; 397(10282): 1351-1362, 2021 04 10.
Article in English | MEDLINE | ID: covidwho-1157794

ABSTRACT

BACKGROUND: 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. We report a post-hoc analysis of the efficacy of the adenoviral vector vaccine, ChAdOx1 nCoV-19 (AZD1222), against this variant. METHODS: Volunteers (aged ≥18 years) who were enrolled in phase 2/3 vaccine efficacy studies in the UK, and who were randomly assigned (1:1) to receive ChAdOx1 nCoV-19 or a meningococcal conjugate control (MenACWY) vaccine, provided upper airway swabs on a weekly basis and also if they developed symptoms of COVID-19 disease (a cough, a fever of 37·8°C or higher, shortness of breath, anosmia, or ageusia). Swabs were tested by nucleic acid amplification test (NAAT) for SARS-CoV-2 and positive samples were sequenced through the COVID-19 Genomics UK consortium. Neutralising antibody responses were measured using a live-virus microneutralisation assay against the B.1.1.7 lineage and a canonical non-B.1.1.7 lineage (Victoria). The efficacy analysis included symptomatic COVID-19 in seronegative participants with a NAAT positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to vaccine received. Vaccine efficacy was calculated as 1 - relative risk (ChAdOx1 nCoV-19 vs MenACWY groups) derived from a robust Poisson regression model. This study is continuing and is registered with ClinicalTrials.gov, NCT04400838, and ISRCTN, 15281137. FINDINGS: Participants in efficacy cohorts were recruited between May 31 and Nov 13, 2020, and received booster doses between Aug 3 and Dec 30, 2020. Of 8534 participants in the primary efficacy cohort, 6636 (78%) were aged 18-55 years and 5065 (59%) were female. Between Oct 1, 2020, and Jan 14, 2021, 520 participants developed SARS-CoV-2 infection. 1466 NAAT positive nose and throat swabs were collected from these participants during the trial. Of these, 401 swabs from 311 participants were successfully sequenced. Laboratory virus neutralisation activity by vaccine-induced antibodies was lower against the B.1.1.7 variant than against the Victoria lineage (geometric mean ratio 8·9, 95% CI 7·2-11·0). Clinical vaccine efficacy against symptomatic NAAT positive infection was 70·4% (95% CI 43·6-84·5) for B.1.1.7 and 81·5% (67·9-89·4) for non-B.1.1.7 lineages. INTERPRETATION: ChAdOx1 nCoV-19 showed reduced neutralisation activity against the B.1.1.7 variant compared with a non-B.1.1.7 variant in vitro, but the vaccine showed efficacy against the B.1.1.7 variant of SARS-CoV-2. FUNDING: UK Research and Innovation, National Institute for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midlands NIHR Clinical Research Network, and AstraZeneca.


Subject(s)
Antibodies, Neutralizing/blood , COVID-19 Vaccines/immunology , COVID-19/prevention & control , COVID-19/virology , SARS-CoV-2/immunology , Adolescent , Adult , COVID-19/epidemiology , COVID-19 Nucleic Acid Testing , COVID-19 Vaccines/adverse effects , Female , Humans , Male , Middle Aged , Nucleic Acid Amplification Techniques , Pandemics/prevention & control , Single-Blind Method , United Kingdom/epidemiology , Viral Load , Young Adult
11.
Emerg Infect Dis ; 27(4): 1155-1158, 2021 04.
Article in English | MEDLINE | ID: covidwho-1140631

ABSTRACT

Prospective serosurveillance of severe acute respiratory syndrome coronavirus 2 in 1,069 healthcare workers in London, UK, demonstrated that nucleocapsid antibody titers were stable and sustained for <12 weeks in 312 seropositive participants. This finding was consistent across demographic and clinical variables and contrasts with reports of short-term antibody waning.


Subject(s)
Antibodies, Viral/blood , Antibody Formation/immunology , COVID-19 Serological Testing , COVID-19 , Coronavirus Nucleocapsid Proteins/immunology , Health Personnel/statistics & numerical data , Adult , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/immunology , COVID-19 Serological Testing/methods , COVID-19 Serological Testing/statistics & numerical data , Female , Humans , London/epidemiology , Male , Phosphoproteins/immunology , SARS-CoV-2/isolation & purification , Seroconversion , Seroepidemiologic Studies
13.
Lancet ; 397(10269): 99-111, 2021 01 09.
Article in English | MEDLINE | ID: covidwho-1057535

ABSTRACT

BACKGROUND: A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials. METHODS: This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674. FINDINGS: Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation. INTERPRETATION: ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca.


Subject(s)
COVID-19 Vaccines , COVID-19/prevention & control , Adolescent , Adult , Aged , Brazil , COVID-19 Vaccines/adverse effects , Double-Blind Method , Female , Humans , Male , Middle Aged , Single-Blind Method , South Africa , Treatment Outcome , United Kingdom , Young Adult
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