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1.
J Infect ; 2022 Apr 08.
Article in English | MEDLINE | ID: covidwho-1778315

ABSTRACT

OBJECTIVES: To evaluate the persistence of immunogenicity three months after third dose boosters. METHODS: COV-BOOST is a multicentre, randomised, controlled, phase 2 trial of seven COVID-19 vaccines used as a third booster dose. The analysis was conducted using all randomised participants who were SARS-CoV-2 naïve during the study. RESULTS: Among the 2883 participants randomised, there were 2422 SARS-CoV-2 naïve participants until D84 visit included in the analysis with median age of 70 (IQR: 30-94) years. In the participants who had two initial doses of ChAd, schedules using mRNA vaccines as third dose have the highest anti-spike IgG at D84 (e.g. geometric mean concentration of 8674 ELU/ml (95% CI: 7461-10085) following ChAd/ChAd/BNT). However, in people who had two initial doses of BNT there was no significant difference at D84 in people given ChAd versus BNT (geometric mean ratio (GMR) of 0.95 (95%CI: 0.78, 1.15). Also, people given Ad26.COV2.S (Janssen; hereafter referred to as Ad26) as a third dose had significantly higher anti-spike IgG at D84 than BNT (GMR of 1.20, 95%CI: 1.01,1.43). Responses at D84 between people who received BNT (15 µg) or BNT (30 µg) after ChAd/ChAd or BNT/BNT were similar, with anti-spike IgG GMRs of half-BNT (15 µg) versus BNT (30 µg) ranging between 0.74-0.86. The decay rate of cellular responses were similar between all the vaccine schedules and doses. CONCLUSIONS: 84 days after a third dose of COVID-19 vaccine the decay rates of humoral response were different between vaccines. Adenoviral vector vaccine anti-spike IgG concentration at D84 following BNT/BNT initial doses were higher than for a three dose (BNT/BNT/BNT) schedule. Half dose BNT immune responses were similar to full dose responses. While high antibody tires are desirable in situations of high transmission of new variants of concern, the maintenance of immune responses that confer long-lasting protection against severe disease or death is also of critical importance. Policymakers may also consider adenoviral vector, fractional dose of mRNA, or other non-mRNA vaccines as third doses.

2.
SSRN; 2022.
Preprint in English | SSRN | ID: ppcovidwho-332455

ABSTRACT

Background: Many high-income countries have deployed third “booster” doses of COVID-19 vaccines to populations and some countries have started offering fourth doses. Methods: The COV-BOOST trial is a multicentre, randomised, controlled, phase II trial of seven COVID-19 vaccines as third dose boosters. The current study invited participants who received BNT162b2 (BNT) as third dose in COV-BOOST to be randomised to receive a fourth dose of BNT or mRNA1273 (50 µg, half-m1273). The COV-BOOST trial is a multicentre, randomised, controlled, phase 2 trial of seven COVID-19 vaccines used as a third booster dose. Results: Between 11 and 25 January 2022, 166 participants in the original BNT arm were randomised and received a fourth dose vaccine. The median age was 70.1 (interquartile range: 51.6-77.5) years with 51.8 % (n=86) female participants. The median interval between third and fourth dose was 208.5 (interquartile range: 203.25-214.75) days.Pain and fatigue were the most common local and systemic solicited adverse events for BNT and half-m1273. None of three serious adverse events reported after a fourth dose were related to study vaccine.The fold rises in anti-spike IgG pre- and post-fourth dose were 12.19 (95%CI: 10.37-14.32) and 15.90 (95%CI: 12.92-19.58) in BNT and half-m1273 arms respectively, with fold changes compared to the post third dose-peak of 1.59 (95%CI: 1.41-1.78) and 2.19 (95%CI: 1.90-2.52). T cell responses also boosted. Conclusions: Fourth dose COVID-19 mRNA booster vaccines are well-tolerated and boost cellular and humoral immunity up to, and beyond peak levels achieved following third dose boosters (ISRCTN: 73765130).

3.
Lancet ; 398(10318): 2258-2276, 2021 12 18.
Article in English | MEDLINE | ID: covidwho-1550152

ABSTRACT

BACKGROUND: Few data exist on the comparative safety and immunogenicity of different COVID-19 vaccines given as a third (booster) dose. To generate data to optimise selection of booster vaccines, we investigated the reactogenicity and immunogenicity of seven different COVID-19 vaccines as a third dose after two doses of ChAdOx1 nCov-19 (Oxford-AstraZeneca; hereafter referred to as ChAd) or BNT162b2 (Pfizer-BioNtech, hearafter referred to as BNT). METHODS: COV-BOOST is a multicentre, randomised, controlled, phase 2 trial of third dose booster vaccination against COVID-19. Participants were aged older than 30 years, and were at least 70 days post two doses of ChAd or at least 84 days post two doses of BNT primary COVID-19 immunisation course, with no history of laboratory-confirmed SARS-CoV-2 infection. 18 sites were split into three groups (A, B, and C). Within each site group (A, B, or C), participants were randomly assigned to an experimental vaccine or control. Group A received NVX-CoV2373 (Novavax; hereafter referred to as NVX), a half dose of NVX, ChAd, or quadrivalent meningococcal conjugate vaccine (MenACWY)control (1:1:1:1). Group B received BNT, VLA2001 (Valneva; hereafter referred to as VLA), a half dose of VLA, Ad26.COV2.S (Janssen; hereafter referred to as Ad26) or MenACWY (1:1:1:1:1). Group C received mRNA1273 (Moderna; hereafter referred to as m1273), CVnCov (CureVac; hereafter referred to as CVn), a half dose of BNT, or MenACWY (1:1:1:1). Participants and all investigatory staff were blinded to treatment allocation. Coprimary outcomes were safety and reactogenicity and immunogenicity of anti-spike IgG measured by ELISA. The primary analysis for immunogenicity was on a modified intention-to-treat basis; safety and reactogenicity were assessed in the intention-to-treat population. Secondary outcomes included assessment of viral neutralisation and cellular responses. This trial is registered with ISRCTN, number 73765130. FINDINGS: Between June 1 and June 30, 2021, 3498 people were screened. 2878 participants met eligibility criteria and received COVID-19 vaccine or control. The median ages of ChAd/ChAd-primed participants were 53 years (IQR 44-61) in the younger age group and 76 years (73-78) in the older age group. In the BNT/BNT-primed participants, the median ages were 51 years (41-59) in the younger age group and 78 years (75-82) in the older age group. In the ChAd/ChAD-primed group, 676 (46·7%) participants were female and 1380 (95·4%) were White, and in the BNT/BNT-primed group 770 (53·6%) participants were female and 1321 (91·9%) were White. Three vaccines showed overall increased reactogenicity: m1273 after ChAd/ChAd or BNT/BNT; and ChAd and Ad26 after BNT/BNT. For ChAd/ChAd-primed individuals, spike IgG geometric mean ratios (GMRs) between study vaccines and controls ranged from 1·8 (99% CI 1·5-2·3) in the half VLA group to 32·3 (24·8-42·0) in the m1273 group. GMRs for wild-type cellular responses compared with controls ranged from 1·1 (95% CI 0·7-1·6) for ChAd to 3·6 (2·4-5·5) for m1273. For BNT/BNT-primed individuals, spike IgG GMRs ranged from 1·3 (99% CI 1·0-1·5) in the half VLA group to 11·5 (9·4-14·1) in the m1273 group. GMRs for wild-type cellular responses compared with controls ranged from 1·0 (95% CI 0·7-1·6) for half VLA to 4·7 (3·1-7·1) for m1273. The results were similar between those aged 30-69 years and those aged 70 years and older. Fatigue and pain were the most common solicited local and systemic adverse events, experienced more in people aged 30-69 years than those aged 70 years or older. Serious adverse events were uncommon, similar in active vaccine and control groups. In total, there were 24 serious adverse events: five in the control group (two in control group A, three in control group B, and zero in control group C), two in Ad26, five in VLA, one in VLA-half, one in BNT, two in BNT-half, two in ChAd, one in CVn, two in NVX, two in NVX-half, and one in m1273. INTERPRETATION: All study vaccines boosted antibody and neutralising responses after ChAd/ChAd initial course and all except one after BNT/BNT, with no safety concerns. Substantial differences in humoral and cellular responses, and vaccine availability will influence policy choices for booster vaccination. FUNDING: UK Vaccine Taskforce and National Institute for Health Research.


Subject(s)
/administration & dosage , COVID-19/prevention & control , Immunization, Secondary/methods , Immunogenicity, Vaccine , Adult , Aged , Aged, 80 and over , COVID-19/immunology , Female , Humans , Male , Middle Aged , Pandemics , Patient Safety , SARS-CoV-2 , United Kingdom
4.
Clin Trials ; 18(5): 615-621, 2021 10.
Article in English | MEDLINE | ID: covidwho-1280563

ABSTRACT

The COVID-19 pandemic has resulted in unprecedented challenges for healthcare systems worldwide. It has also stimulated research in a wide range of areas including rapid diagnostics, novel therapeutics, use of technology to track patients and vaccine development. Here, we describe our experience of rapidly setting up and delivering a novel COVID-19 vaccine trial, using clinical and research staff and facilities in three National Health Service Trusts in Cambridgeshire, United Kingdom. We encountered and overcame a number of challenges including differences in organisational structures, research facilities available, staff experience and skills, information technology and communications infrastructure, and research training and assessment procedures. We overcame these by setting up a project team that included key members from all three organisations that met at least daily by teleconference. This group together worked to identify the best practices and procedures and to harmonise and cascade these to the wider trial team. This enabled us to set up the trial within 25 days and to recruit and vaccinate the participants within a further 23 days. The lessons learned from our experiences could be used to inform the conduct of clinical trials during a future infectious disease pandemic or public health emergency.


Subject(s)
COVID-19 Vaccines/therapeutic use , COVID-19 , Clinical Trials as Topic/standards , Pandemics , COVID-19/prevention & control , Clinical Trials as Topic/organization & administration , Humans , Pandemics/prevention & control , State Medicine , United Kingdom/epidemiology
5.
Cell Rep Med ; 1(6): 100099, 2020 09 22.
Article in English | MEDLINE | ID: covidwho-738567

ABSTRACT

Rapid COVID-19 diagnosis in the hospital is essential, although this is complicated by 30%-50% of nose/throat swabs being negative by SARS-CoV-2 nucleic acid amplification testing (NAAT). Furthermore, the D614G spike mutant dominates the pandemic and it is unclear how serological tests designed to detect anti-spike antibodies perform against this variant. We assess the diagnostic accuracy of combined rapid antibody point of care (POC) and nucleic acid assays for suspected COVID-19 disease due to either wild-type or the D614G spike mutant SARS-CoV-2. The overall detection rate for COVID-19 is 79.2% (95% CI 57.8-92.9) by rapid NAAT alone. The combined point of care antibody test and rapid NAAT is not affected by D614G and results in very high sensitivity for COVID-19 diagnosis with very high specificity.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , Point-of-Care Testing , SARS-CoV-2/isolation & purification , Aged , Aged, 80 and over , Antibodies, Viral/blood , COVID-19 Testing/standards , Female , Humans , Immunoassay , Male , Middle Aged , Neutralization Tests , Nucleic Acid Amplification Techniques , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Sensitivity and Specificity , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology
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