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1.
PLoS One ; 17(6): e0270150, 2022.
Article in English | MEDLINE | ID: covidwho-1896493

ABSTRACT

We urgently need answers to basic epidemiological questions regarding SARS-CoV-2 infection in pregnant and postpartum women and its effect on their newborns. While many national registries, health facilities, and research groups are collecting relevant data, we need a collaborative and methodologically rigorous approach to better combine these data and address knowledge gaps, especially those related to rare outcomes. We propose that using a sequential, prospective meta-analysis (PMA) is the best approach to generate data for policy- and practice-oriented guidelines. As the pandemic evolves, additional studies identified retrospectively by the steering committee or through living systematic reviews will be invited to participate in this PMA. Investigators can contribute to the PMA by either submitting individual patient data or running standardized code to generate aggregate data estimates. For the primary analysis, we will pool data using two-stage meta-analysis methods. The meta-analyses will be updated as additional data accrue in each contributing study and as additional studies meet study-specific time or data accrual thresholds for sharing. At the time of publication, investigators of 25 studies, including more than 76,000 pregnancies, in 41 countries had agreed to share data for this analysis. Among the included studies, 12 have a contemporaneous comparison group of pregnancies without COVID-19, and four studies include a comparison group of non-pregnant women of reproductive age with COVID-19. Protocols and updates will be maintained publicly. Results will be shared with key stakeholders, including the World Health Organization (WHO) Maternal, Newborn, Child, and Adolescent Health (MNCAH) Research Working Group. Data contributors will share results with local stakeholders. Scientific publications will be published in open-access journals on an ongoing basis.


Subject(s)
COVID-19 , Adolescent , COVID-19/epidemiology , Child , Female , Humans , Infant, Newborn , Meta-Analysis as Topic , Postpartum Period , Pregnancy , Prospective Studies , Retrospective Studies , SARS-CoV-2
2.
Vaccine ; 2022 Jun 14.
Article in English | MEDLINE | ID: covidwho-1886120

ABSTRACT

Replication-deficient adenoviral vectors have been under investigation as a platform technology for vaccine development for several years and have recently been successfully deployed as an effective COVID-19 counter measure. A replication-deficient adenoviral vector based on the simian adenovirus type Y25 and named ChAdOx1 has been evaluated in several clinical trials since 2012. The Brighton Collaboration Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) was formed to evaluate the safety and other key features of new platform technology vaccines. This manuscript reviews key features of the ChAdOx1-vectored vaccines. The simian adenovirus Y25 was chosen as a strategy to circumvent pre-existing immunity to common human adenovirus serotypes which could impair immune responses induced by adenoviral vectored vaccines. Deletion of the E1 gene renders the ChAdOx1 vector replication incompetent and further genetic engineering of the E3 and E4 genes allows for increased insertional capability and optimizes vaccine manufacturing processes. ChAdOx1 vectored vaccines can be manufactured in E1 complementing cell lines at scale and are thermostable. The first ChAdOx1 vectored vaccines approved for human use, against SARS-CoV-2, received emergency use authorization in the UK on 30th December 2020, and is now approved in more than 180 countries. Safety data were compiled from phase I-III clinical trials of ChAdOx1 vectored vaccines expressing different antigens (influenza, tuberculosis, malaria, meningococcal B, prostate cancer, MERS-CoV, Chikungunya, Zika and SARS-CoV-2), conducted by the University of Oxford, as well as post marketing surveillance data for the COVID-19 Oxford-AstraZeneca vaccine. Overall, ChAdOx1 vectored vaccines have been well tolerated. Very rarely, thrombosis with thrombocytopenia syndrome (TTS), capillary leak syndrome (CLS), immune thrombocytopenia (ITP), and Guillain-Barre syndrome (GBS) have been reported following mass administration of the COVID-19 Oxford-AstraZeneca vaccine. The benefits of this COVID-19 vaccination have outweighed the risks of serious adverse events in most settings, especially with mitigation of risks when possible. Extensive immunogenicity clinical evaluation of ChAdOx1 vectored vaccines reveal strong, durable humoral and cellular immune responses to date; studies to refine the COVID-19 protection (e.g., via homologous/heterologous booster, fractional dose) are also underway. New prophylactic and therapeutic vaccines based on the ChAdOx1 vector are currently undergoing pre-clinical and clinical assessment, including vaccines against viral hemorrhagic fevers, Nipah virus, HIV, Hepatitis B, amongst others.

3.
Vaccine ; 2022 Jun 14.
Article in English | MEDLINE | ID: covidwho-1886119

ABSTRACT

Inactivated viral vaccines have long been used in humans for diseases of global health threat (e.g., poliomyelitis and pandemic and seasonal influenza) and the technology of inactivation has more recently been used for emerging diseases such as West Nile, Chikungunya, Ross River, SARS and especially for COVID-19. The Brighton Collaboration Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) Working Group has prepared standardized templates to describe the key considerations for the benefit and risk of several vaccine platform technologies, including inactivated viral vaccines. This paper uses the BRAVATO inactivated virus vaccine template to review the features of an inactivated whole chikungunya virus (CHIKV) vaccine that has been evaluated in several preclinical studies and clinical trials. The inactivated whole CHIKV vaccine was cultured on Vero cells and inactivated by ß-propiolactone. This provides an effective, flexible system for high-yield manufacturing. The inactivated whole CHIKV vaccine has favorable thermostability profiles, compatible with vaccine supply chains. Safety data are compiled in the current inactivated whole CHIKV vaccine safety database with unblinded data from the ongoing studies: 850 participants from phase II study (parts A and B) outside of India, and 600 participants from ongoing phase II study in India, and completed phase I clinical studies for 60 subjects. Overall, the inactivated whole CHIKV vaccine has been well tolerated, with no significant safety issues identified. Evaluation of the inactivated whole CHIKV vaccine is continuing, with 1410 participants vaccinated as of 20 April 2022. Extensive evaluation of immunogenicity in humans shows strong, durable humoral immune responses.

4.
Vaccine ; 2022 Jun 09.
Article in English | MEDLINE | ID: covidwho-1882613

ABSTRACT

The Brighton Collaboration Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) Working Group has prepared standardized templates to describe the key considerations for the benefit-risk assessment of several vaccine platform technologies, including nucleic acid (RNA and DNA) vaccines. This paper uses the BRAVATO template to review the features of a vaccine employing a proprietary mRNA vaccine platform to develop Moderna COVID-19 Vaccine (mRNA-1273); a highly effective vaccine to prevent coronavirus disease 2019 (Covid-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In response to the pandemic the first in human studies began in March 2020 and the pivotal, placebo-controlled phase 3 efficacy study in over 30,000 adults began in July 2020. Based on demonstration of efficacy and safety at the time of interim analysis in November 2020 and at the time of trial unblinding in March 2021, the mRNA-1273 received Emergency Use Authorization in December 2020 and full FDA approval in January 2022.

5.
BMJ Open ; 12(1): e053820, 2022 01 11.
Article in English | MEDLINE | ID: covidwho-1632977

ABSTRACT

INTRODUCTION: Assessing the impact of COVID-19 policy is critical for informing future policies. However, there are concerns about the overall strength of COVID-19 impact evaluation studies given the circumstances for evaluation and concerns about the publication environment. METHODS: We included studies that were primarily designed to estimate the quantitative impact of one or more implemented COVID-19 policies on direct SARS-CoV-2 and COVID-19 outcomes. After searching PubMed for peer-reviewed articles published on 26 November 2020 or earlier and screening, all studies were reviewed by three reviewers first independently and then to consensus. The review tool was based on previously developed and released review guidance for COVID-19 policy impact evaluation. RESULTS: After 102 articles were identified as potentially meeting inclusion criteria, we identified 36 published articles that evaluated the quantitative impact of COVID-19 policies on direct COVID-19 outcomes. Nine studies were set aside because the study design was considered inappropriate for COVID-19 policy impact evaluation (n=8 pre/post; n=1 cross-sectional), and 27 articles were given a full consensus assessment. 20/27 met criteria for graphical display of data, 5/27 for functional form, 19/27 for timing between policy implementation and impact, and only 3/27 for concurrent changes to the outcomes. Only 4/27 were rated as overall appropriate. Including the 9 studies set aside, reviewers found that only four of the 36 identified published and peer-reviewed health policy impact evaluation studies passed a set of key design checks for identifying the causal impact of policies on COVID-19 outcomes. DISCUSSION: The reviewed literature directly evaluating the impact of COVID-19 policies largely failed to meet key design criteria for inference of sufficient rigour to be actionable by policy-makers. More reliable evidence review is needed to both identify and produce policy-actionable evidence, alongside the recognition that actionable evidence is often unlikely to be feasible.


Subject(s)
COVID-19 , Cross-Sectional Studies , Health Policy , Humans , Research Design , SARS-CoV-2
7.
Trials ; 22(1): 780, 2021 Nov 07.
Article in English | MEDLINE | ID: covidwho-1582024

ABSTRACT

Non-pharmaceutical interventions (NPI) for infectious diseases such as COVID-19 are particularly challenging given the complexities of what is both practical and ethical to randomize. We are often faced with the difficult decision between having weak trials or not having a trial at all. In a recent article, Dr. Atle Fretheim argues that statistically underpowered studies are still valuable, particularly in conjunction with other similar studies in meta-analysis in the context of the DANMASK-19 trial, asking "Surely, some trial evidence must be better than no trial evidence?" However, informative trials are not always feasible, and feasible trials are not always informative. In some cases, even a well-conducted but weakly designed and/or underpowered trial such as DANMASK-19 may be uninformative or worse, both individually and in a body of literature. Meta-analysis, for example, can only resolve issues of statistical power if there is a reasonable expectation of compatible well-designed trials. Uninformative designs may also invite misinformation. Here, we make the case that-when considering informativeness, ethics, and opportunity costs in addition to statistical power-"nothing" is often the better choice.


Subject(s)
COVID-19 , Randomized Controlled Trials as Topic , Humans
8.
BMC Infect Dis ; 21(1): 1170, 2021 Nov 20.
Article in English | MEDLINE | ID: covidwho-1526605

ABSTRACT

BACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care.


Subject(s)
COVID-19 , COVID-19/therapy , Humans , Immunization, Passive , Randomized Controlled Trials as Topic , SARS-CoV-2 , Treatment Outcome
9.
JAMA ; 325(12): 1185-1195, 2021 03 23.
Article in English | MEDLINE | ID: covidwho-1178926

ABSTRACT

Importance: Convalescent plasma is a proposed treatment for COVID-19. Objective: To assess clinical outcomes with convalescent plasma treatment vs placebo or standard of care in peer-reviewed and preprint publications or press releases of randomized clinical trials (RCTs). Data Sources: PubMed, the Cochrane COVID-19 trial registry, and the Living Overview of Evidence platform were searched until January 29, 2021. Study Selection: The RCTs selected compared any type of convalescent plasma vs placebo or standard of care for patients with confirmed or suspected COVID-19 in any treatment setting. Data Extraction and Synthesis: Two reviewers independently extracted data on relevant clinical outcomes, trial characteristics, and patient characteristics and used the Cochrane Risk of Bias Assessment Tool. The primary analysis included peer-reviewed publications of RCTs only, whereas the secondary analysis included all publicly available RCT data (peer-reviewed publications, preprints, and press releases). Inverse variance-weighted meta-analyses were conducted to summarize the treatment effects. The certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation. Main Outcomes and Measures: All-cause mortality, length of hospital stay, clinical improvement, clinical deterioration, mechanical ventilation use, and serious adverse events. Results: A total of 1060 patients from 4 peer-reviewed RCTs and 10 722 patients from 6 other publicly available RCTs were included. The summary risk ratio (RR) for all-cause mortality with convalescent plasma in the 4 peer-reviewed RCTs was 0.93 (95% CI, 0.63 to 1.38), the absolute risk difference was -1.21% (95% CI, -5.29% to 2.88%), and there was low certainty of the evidence due to imprecision. Across all 10 RCTs, the summary RR was 1.02 (95% CI, 0.92 to 1.12) and there was moderate certainty of the evidence due to inclusion of unpublished data. Among the peer-reviewed RCTs, the summary hazard ratio was 1.17 (95% CI, 0.07 to 20.34) for length of hospital stay, the summary RR was 0.76 (95% CI, 0.20 to 2.87) for mechanical ventilation use (the absolute risk difference for mechanical ventilation use was -2.56% [95% CI, -13.16% to 8.05%]), and there was low certainty of the evidence due to imprecision for both outcomes. Limited data on clinical improvement, clinical deterioration, and serious adverse events showed no significant differences. Conclusions and Relevance: Treatment with convalescent plasma compared with placebo or standard of care was not significantly associated with a decrease in all-cause mortality or with any benefit for other clinical outcomes. The certainty of the evidence was low to moderate for all-cause mortality and low for other outcomes.


Subject(s)
COVID-19/therapy , Adult , Bias , COVID-19/mortality , Cause of Death , Female , Humans , Immunization, Passive/adverse effects , Length of Stay , Male , Placebos/therapeutic use , Randomized Controlled Trials as Topic , Respiration, Artificial , Standard of Care , Treatment Outcome
10.
Front Pediatr ; 9: 642508, 2021.
Article in English | MEDLINE | ID: covidwho-1178014

ABSTRACT

Background: The coronavirus disease (COVID-19) has spread worldwide with an increasing number of patients, including pregnant women and neonates. This study aims to evaluate morbidity and mortality in the COVID-19 era compared to the preceding year in the Neonatal Intensive Care Unit (NICU) at Tamale Teaching Hospital, Ghana. Methods: This is a cross-sectional study carried out on neonates admitted to NICU between March 1st to August 31st, 2019 (pre-COVID-19 era) and March 1st to August 31st, 2020 (COVID-19 era). Multivariate logistic regression was performed to identify predictors of mortality for both periods. Results: From 2,901 neonates, 1,616 (56%) were admitted before, and 1,285 (44%) were admitted during the pandemic. Admissions decreased during the COVID-19 era, reaching their lowest point between June and August 2020. Compared to the previous year, during the COVID-19 era, admissions of patients born at TTH, delivered at home, and with infections decreased from 50 to 39%, 7 to 4%, and 22 to 13%, respectively. Referred status (OR = 3.3) and vaginal delivery (OR = 1.6) were associated with an increased likelihood of mortality. For low- birth weight neonates, admissions of patients born at TTH, with vaginal and home delivery decreased from 62 to 48%, 8 to 2%, and 59 to 52%, respectively. Neonatal infections and congenital anomalies decreased from 8 to 4%, 5 to 3%, respectively. The likelihood of mortality among referred patients increased by 50%. Conclusion: We observed a marked decrease in admissions and change in the diagnosis landscape and related mortality during the pandemic. Underlying challenges, including fear, financing, and health system capacity, might intensify delays and lack of access to newborn care in northern Ghana, leading to higher rates of lifelong disabilities and mortality. Immediate damage control measures, including an improved home-based continuum of care and equipping families to participate in the newborn care with complemented m-health approaches, are needed with urgency.

11.
Elife ; 102021 03 02.
Article in English | MEDLINE | ID: covidwho-1112865

ABSTRACT

COVID-19 poses a major challenge to care homes, as SARS-CoV-2 is readily transmitted and causes disproportionately severe disease in older people. Here, 1167 residents from 337 care homes were identified from a dataset of 6600 COVID-19 cases from the East of England. Older age and being a care home resident were associated with increased mortality. SARS-CoV-2 genomes were available for 700 residents from 292 care homes. By integrating genomic and temporal data, 409 viral clusters within the 292 homes were identified, indicating two different patterns - outbreaks among care home residents and independent introductions with limited onward transmission. Approximately 70% of residents in the genomic analysis were admitted to hospital during the study, providing extensive opportunities for transmission between care homes and hospitals. Limiting viral transmission within care homes should be a key target for infection control to reduce COVID-19 mortality in this population.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , Nursing Homes , SARS-CoV-2/genetics , Aged, 80 and over , COVID-19/virology , Disease Outbreaks , England/epidemiology , Female , Humans , Infectious Disease Transmission, Patient-to-Professional , Infectious Disease Transmission, Professional-to-Patient , Male , Polymorphism, Single Nucleotide , Sequence Analysis , Time Factors
12.
JAMA ; 325(12): 1185-1195, 2021 03 23.
Article in English | MEDLINE | ID: covidwho-1103251

ABSTRACT

Importance: Convalescent plasma is a proposed treatment for COVID-19. Objective: To assess clinical outcomes with convalescent plasma treatment vs placebo or standard of care in peer-reviewed and preprint publications or press releases of randomized clinical trials (RCTs). Data Sources: PubMed, the Cochrane COVID-19 trial registry, and the Living Overview of Evidence platform were searched until January 29, 2021. Study Selection: The RCTs selected compared any type of convalescent plasma vs placebo or standard of care for patients with confirmed or suspected COVID-19 in any treatment setting. Data Extraction and Synthesis: Two reviewers independently extracted data on relevant clinical outcomes, trial characteristics, and patient characteristics and used the Cochrane Risk of Bias Assessment Tool. The primary analysis included peer-reviewed publications of RCTs only, whereas the secondary analysis included all publicly available RCT data (peer-reviewed publications, preprints, and press releases). Inverse variance-weighted meta-analyses were conducted to summarize the treatment effects. The certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation. Main Outcomes and Measures: All-cause mortality, length of hospital stay, clinical improvement, clinical deterioration, mechanical ventilation use, and serious adverse events. Results: A total of 1060 patients from 4 peer-reviewed RCTs and 10 722 patients from 6 other publicly available RCTs were included. The summary risk ratio (RR) for all-cause mortality with convalescent plasma in the 4 peer-reviewed RCTs was 0.93 (95% CI, 0.63 to 1.38), the absolute risk difference was -1.21% (95% CI, -5.29% to 2.88%), and there was low certainty of the evidence due to imprecision. Across all 10 RCTs, the summary RR was 1.02 (95% CI, 0.92 to 1.12) and there was moderate certainty of the evidence due to inclusion of unpublished data. Among the peer-reviewed RCTs, the summary hazard ratio was 1.17 (95% CI, 0.07 to 20.34) for length of hospital stay, the summary RR was 0.76 (95% CI, 0.20 to 2.87) for mechanical ventilation use (the absolute risk difference for mechanical ventilation use was -2.56% [95% CI, -13.16% to 8.05%]), and there was low certainty of the evidence due to imprecision for both outcomes. Limited data on clinical improvement, clinical deterioration, and serious adverse events showed no significant differences. Conclusions and Relevance: Treatment with convalescent plasma compared with placebo or standard of care was not significantly associated with a decrease in all-cause mortality or with any benefit for other clinical outcomes. The certainty of the evidence was low to moderate for all-cause mortality and low for other outcomes.


Subject(s)
COVID-19/therapy , Adult , Bias , COVID-19/mortality , Cause of Death , Female , Humans , Immunization, Passive/adverse effects , Length of Stay , Male , Placebos/therapeutic use , Randomized Controlled Trials as Topic , Respiration, Artificial , Standard of Care , Treatment Outcome
14.
Am J Trop Med Hyg ; 104(2): 461-465, 2020 Dec 28.
Article in English | MEDLINE | ID: covidwho-1000469

ABSTRACT

In the African context, there is a paucity of data on SARS-CoV-2 infection and associated COVID-19 in pregnancy. Given the endemicity of infections such as malaria, HIV, and tuberculosis (TB) in sub-Saharan Africa (SSA), it is important to evaluate coinfections with SARS-CoV-2 and their impact on maternal/infant outcomes. Robust research is critically needed to evaluate the effects of the added burden of COVID-19 in pregnancy, to help develop evidence-based policies toward improving maternal and infant outcomes. In this perspective, we briefly review current knowledge on the clinical features of COVID-19 in pregnancy; the risks of preterm birth and cesarean delivery secondary to comorbid severity; the effects of maternal SARS-CoV-2 infection on the fetus/neonate; and in utero mother-to-child SARS-CoV-2 transmission. We further highlight the need to conduct multicountry surveillance as well as retrospective and prospective cohort studies across SSA. This will enable assessments of SARS-CoV-2 burden among pregnant African women and improve the understanding of the spectrum of COVID-19 manifestations in this population, which may be living with or without HIV, TB, and/or other coinfections/comorbidities. In addition, multicountry studies will allow a better understanding of risk factors and outcomes to be compared across countries and subregions. Such an approach will encourage and strengthen much-needed intra-African, south-to-south multidisciplinary and interprofessional research collaborations. The African Forum for Research and Education in Health's COVID-19 Research Working Group has embarked upon such a collaboration across Western, Central, Eastern and Southern Africa.


Subject(s)
COVID-19/complications , COVID-19/epidemiology , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/virology , Research , Africa South of the Sahara/epidemiology , COVID-19/mortality , Coinfection/complications , Coinfection/epidemiology , Female , Humans , Infant, Newborn , Infectious Disease Transmission, Vertical , Intersectoral Collaboration , Pregnancy , Pregnant Women , Premature Birth , Prospective Studies , Retrospective Studies , Risk Factors , SARS-CoV-2/pathogenicity , Socioeconomic Factors
15.
Vaccine ; 38(49): 7702-7707, 2020 11 17.
Article in English | MEDLINE | ID: covidwho-867163

ABSTRACT

Several live-attenuated viral vaccine candidates are among the COVID-19 vaccines in development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of live-attenuated viral vaccines. This will help key stakeholders assess potential safety issues and understand the benefit-risk of such vaccines. The standardized and structured assessment provided by the template would also help to contribute to improved communication and support public acceptance of licensed live-attenuated viral vaccines.


Subject(s)
Drug Evaluation, Preclinical/standards , Vaccines, Attenuated/adverse effects , Viral Vaccines/adverse effects , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/pharmacology , Drug Evaluation, Preclinical/methods , Humans , Risk Assessment , Societies, Scientific , Vaccines, Attenuated/pharmacology , Viral Vaccines/pharmacology
16.
Vaccine ; 39(22): 3081-3101, 2021 05 21.
Article in English | MEDLINE | ID: covidwho-813888

ABSTRACT

Replication-incompetent adenoviral vectors have been under investigation as a platform to carry a variety of transgenes, and express them as a basis for vaccine development. A replication-incompetent adenoviral vector based on human adenovirus type 26 (Ad26) has been evaluated in several clinical trials. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety and features of recombinant viral vector vaccines. This paper reviews features of the Ad26 vectors, including tabulation of safety and risk assessment characteristics of Ad26-based vaccines. In the Ad26 vector, deletion of E1 gene rendering the vector replication incompetent is combined with additional genetic engineering for vaccine manufacturability and transgene expression optimization. These vaccines can be manufactured in mammalian cell lines at scale providing an effective, flexible system for high-yield manufacturing. Ad26 vector vaccines have favorable thermostability profiles, compatible with vaccine supply chains. Safety data are compiled in the Ad26 vaccine safety database version 4.0, with unblinded data from 23 ongoing and completed clinical studies for 3912 participants in five different Ad26-based vaccine programs. Overall, Ad26-based vaccines have been well tolerated, with no significant safety issues identified. Evaluation of Ad26-based vaccines is continuing, with >114,000 participants vaccinated as of 4th September 2020. Extensive evaluation of immunogenicity in humans shows strong, durable humoral and cellular immune responses. Clinical trials have not revealed impact of pre-existing immunity to Ad26 on vaccine immunogenicity, even in the presence of Ad26 neutralizing antibody titers or Ad26-targeting T cell responses at baseline. The first Ad26-based vaccine, against Ebola virus, received marketing authorization from EC on 1st July 2020, as part of the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen. New developments based on Ad26 vectors are underway, including a COVID-19 vaccine, which is currently in phase 3 of clinical evaluation.


Subject(s)
COVID-19 , Ebolavirus , Viral Vaccines , Animals , COVID-19 Vaccines , Genetic Vectors , Humans , Risk Assessment , SARS-CoV-2 , Viral Vaccines/genetics
17.
Vaccine ; 38(49): 7708-7715, 2020 11 17.
Article in English | MEDLINE | ID: covidwho-745909

ABSTRACT

Many of the vaccines under development for COVID-19 involve the use of viral vectors. The Brighton Collaboration Benefit-Risk Assessment of Vaccines by Technology (BRAVATO, formerly the Viral Vector Vaccine Safety Working Group, V3SWG) working group has prepared a standardized template to describe the key considerations for the benefit-risk assessment of viral vector vaccines. This will facilitate key stakeholders to anticipate potential safety issues and interpret or assess safety data. This would also help improve communication and public acceptance of licensed viral vector vaccines.


Subject(s)
Drug Evaluation, Preclinical/standards , Vaccines, Attenuated/adverse effects , Viral Vaccines/adverse effects , Animals , Genetic Vectors , Humans , Internet , Risk Assessment
18.
Vaccine ; 38(39): 6184-6189, 2020 09 03.
Article in English | MEDLINE | ID: covidwho-701883

ABSTRACT

Inactivated viral vaccines have long been used in humans for diseases of global health threat and are now among the vaccines for COVID-19 under development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of inactivated viral vaccines. This will help key stakeholders to assess potential safety issues and understand the benefit-risk of the vaccine platform. The standardized and structured assessment provided by the template would also help to contribute to improved communication and support public acceptance of licensed inactivated viral vaccines.


Subject(s)
Coronavirus Infections/prevention & control , Drug Approval/legislation & jurisprudence , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Risk Assessment , Viral Vaccines/standards , Betacoronavirus/drug effects , Betacoronavirus/immunology , Betacoronavirus/pathogenicity , COVID-19 , COVID-19 Vaccines , Civil Defense , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Government Regulation , Humans , Immunogenicity, Vaccine , International Cooperation , Patient Safety , Pneumonia, Viral/epidemiology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , SARS-CoV-2 , Vaccines, Inactivated , Viral Vaccines/administration & dosage , Viral Vaccines/biosynthesis
19.
Vaccine ; 38(35): 5734-5739, 2020 07 31.
Article in English | MEDLINE | ID: covidwho-640754

ABSTRACT

Several protein vaccine candidates are among the COVID-19 vaccines in development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of protein vaccines. This will help key stakeholders to assess potential safety issues and understand the benefit-risk of such a vaccine platform. The structured and standardized assessment provided by the template would also help contribute to improved public acceptance and communication of licensed protein vaccines.


Subject(s)
Viral Vaccines/adverse effects , Viral Vaccines/immunology , Antigens, Viral/administration & dosage , Antigens, Viral/adverse effects , Antigens, Viral/immunology , COVID-19 Vaccines , Coronavirus Infections/immunology , Coronavirus Infections/prevention & control , Humans , Patient Safety , Risk Assessment , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/immunology , Viral Proteins/administration & dosage , Viral Proteins/adverse effects , Viral Proteins/immunology , Viral Vaccines/administration & dosage
20.
Vaccine ; 38(34): 5556-5561, 2020 07 22.
Article in English | MEDLINE | ID: covidwho-617212

ABSTRACT

Nucleic acid (DNA and RNA) vaccines are among the most advanced vaccines for COVID-19 under development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of nucleic acid vaccines. This will facilitate the assessment by key stakeholders of potential safety issues and understanding of overall benefit-risk. The structured assessment provided by the template can also help improve communication and public acceptance of licensed nucleic acid vaccines.


Subject(s)
Risk Assessment/methods , Vaccines, DNA/adverse effects , Vaccines, DNA/standards , Viral Vaccines/genetics , Viral Vaccines/standards , COVID-19 Vaccines , Coronavirus Infections/genetics , Coronavirus Infections/prevention & control , Humans , Public Opinion , Risk Assessment/standards , Vaccines, DNA/genetics , Viral Vaccines/adverse effects
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