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1.
Vaccine ; 42(7): 1812-1825, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38368225

ABSTRACT

This report introduces a Brighton Collaboration (BC) case definition for autoimmune hepatitis (AIH), which has been classified as a priority adverse event of special interest (AESI), as there were possible cases seen following COVID-19 vaccination. The case definition was developed by a group of subject matter and BC process experts to facilitate safety data comparability across pre- and post-licensure clinical trials, as well as pharmacovigilance activities in multiple settings with diverse resources and healthcare access. The usual BC case definition development process was followed in an expedited manner, and took two months to complete, including finalising the manuscript for publication, instead of the usual 1 year development time. It includes a systematic review of the literature and an expert consensus to define levels of diagnostic certainty for AIH, and provides specific guidelines for data collection and analysis. Histology, serological and biochemical tests and exclusion of alternate diagnosis were considered necessary to define the levels of certainty (definitive, probable and possible). AEFI reports of suspected AIH were independently classified by the WG members to test its useability and these classifications were used to finalise the case definition. The document underwent peer review by external AIH experts and a Reference Group of vaccine safety stakeholders in high-, low- and middle-income countries to ensure case definition useability, applicability, and scientific integrity. The expedited process can be replicated for development of other standardised case definitions for priority AESIs for endemics and epidemics. While applicable to cases reported following immunisation, the case definition is independent of lapsed time following vaccination and, as such, can also be used to determine background incidence for vaccinated and unvaccinated control groups in studies of causal association. While use of this case definition is also appropriate for the study of safety of other products including drugs, it is not meant to guide clinical case management.


Subject(s)
Hepatitis, Autoimmune , Humans , Hepatitis, Autoimmune/diagnosis , COVID-19 Vaccines/adverse effects , Pharmacovigilance , Data Collection/standards , Vaccination/adverse effects , Adverse Drug Reaction Reporting Systems/standards , COVID-19/prevention & control , COVID-19/diagnosis , Immunization/adverse effects , SARS-CoV-2/immunology
2.
Vaccine ; 42(4): 969-971, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-37563049

ABSTRACT

Benefit-risk assessment (BRA) is critical for decision-making throughout the vaccine life cycle. It requires scientific assessment of evidence to make an informed judgment on whether the vaccine has a favourable benefit-risk profile i.e. the benefits of the vaccine outweigh its risks for use in its intended indication. The assessment must also consider data gaps and uncertainties, using sensitivity analyses to show the impact of these uncertainties in the assessment. The BRA field has advanced considerably over the past years, including the use of structured BRA frameworks, quantitative BRA models and use of the patient experience data. Analytical tools and procedures to standardize BRA implementation have become increasingly important. A Benefit-Risk Assessment Module has been prepared to enable the planning, assessment, and communication of relevant BRA information via a structured B-R framework. The module can help facilitate the conduct and communication of defensible BRAs by vaccine developers, funders, regulators and policy makers in high, middle or low-income countries, both for regulatory submissions and in public health responses to infectious diseases, including for epidemics.


Subject(s)
Vaccines , Humans , Risk Assessment/methods , Communication , Uncertainty
3.
Vaccine ; 42(4): 972-986, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38135642

ABSTRACT

Vaccine Benefit-Risk (B-R) assessment consists of evaluating the benefits and risks of a vaccine and making a judgment whether the expected key benefits outweigh the potential key risks associated with its expected use. B-R supports regulatory and public health decision-making throughout the vaccine's lifecycle. In August 2021, the Brighton Collaboration's Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) Benefit-Risk Assessment Module working group was established to develop a standard module to support the planning, conduct and evaluation of structured B-R assessments for vaccines from different platforms, based on data from clinical trials, post-marketing studies and real-world evidence. It enables sharing of relevant information via value trees, effects tables and graphical depictions of B-R trade-offs. It is intended to support vaccine developers, funders, regulators and policy makers in high-, middle- or low-income countries to help inform decision-making and facilitate transparent communication concerning development, licensure, deployment and other lifecycle decisions.


Subject(s)
Vaccines , Risk Assessment , Vaccines/adverse effects , Humans
7.
Vaccine ; 41(15): 2605-2614, 2023 04 06.
Article in English | MEDLINE | ID: mdl-36435707

ABSTRACT

The Brighton Collaboration (BC) has formulated a number of case definitions which have primarily been applied to adverse events of special interest in the context of vaccine safety surveillance. This is a revision of the 2007 BC case definition for anaphylaxis. Recently, the BC definition has been widely used for evaluating reports of suspected anaphylaxis following COVID-19 vaccination. This has led to debate about the performance of the BC definition in comparison with those from the US National Institute of Allergy and Infectious Disease/Food Allergy Anaphylaxis Network (NIAID/FAAN) and the World Allergy Organization (WAO). BC convened an expert working group to revise the case definition based on their usual process of literature review and expert consensus. This manuscript presents the outcome of this process and proposes a revised case definition for anaphylaxis. Major and minor criteria have been re-evaluated with an emphasis on the reporting of observable clinical signs, rather than subjective symptoms, and a clearer approach to the ascertainment of levels of certainty is provided. The BC case definition has also been aligned with other contemporary and international case definitions for anaphylaxis.


Subject(s)
Anaphylaxis , COVID-19 Vaccines , COVID-19 , Humans , Anaphylaxis/diagnosis , Anaphylaxis/etiology , COVID-19/prevention & control , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/adverse effects , Vaccination/adverse effects , Vaccines/adverse effects
9.
Clin Infect Dis ; 75(Suppl 1): S11-S17, 2022 08 15.
Article in English | MEDLINE | ID: mdl-35680552

ABSTRACT

Within 2 years after the start of the coronavirus disease 2019 (COVID-19) pandemic, novel severe acute respiratory syndrome coronavirus 2 vaccines were developed, rigorously evaluated in large phase 3 trials, and administered to more than 5 billion individuals globally. However, adverse events of special interest (AESIs) have been described post-implementation, including myocarditis after receipt of messenger RNA (mRNA) vaccines and thrombosis with thrombocytopenia syndrome after receipt of adenoviral vector vaccines. AESIs are rare (<1 to 10/100 000 vaccinees) and less frequent than COVID-19 complications, though they have associated morbidity and mortality. The diversity of COVID-19 vaccine platforms (eg, mRNA, viral vector, protein) and rates of AESIs both between and within platforms (eg, higher rate of myocarditis after mRNA-1273 vs BNT162b2 vaccines) present an important opportunity to advance vaccine safety science. The International Network of Special Immunization Services has been formed with experts in vaccine safety, systems biology, and other relevant disciplines to study cases of AESIs and matched controls to uncover the pathogenesis of rare AESIs and inform vaccine development.


Subject(s)
COVID-19 , Myocarditis , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Humans , Immunization , Pandemics/prevention & control , RNA, Messenger
10.
Vaccine ; 40(35): 5263-5274, 2022 08 19.
Article in English | MEDLINE | ID: mdl-35715351

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.


Subject(s)
COVID-19 , Chikungunya Fever , Chikungunya virus , Viral Vaccines , Animals , Antibodies, Viral , COVID-19/prevention & control , Chikungunya Fever/prevention & control , Chlorocebus aethiops , Humans , Risk Assessment , Vaccines, Inactivated , Vero Cells
11.
Vaccine ; 40(14): 2140-2149, 2022 03 25.
Article in English | MEDLINE | ID: mdl-35248422

ABSTRACT

While the degree of COVID-19 vaccine accessibility and uptake varies at both national and global levels, increasing vaccination coverage raises questions regarding the standard of prevention that ought to apply to different settings where COVID-19 vaccine trials are hosted. A WHO Expert Group has developed guidance on the ethical implications of conducting placebo-controlled trials in the context of expanding global COVID-19 vaccine coverage. The guidance also considers alternative trial designs to placebo controlled trials in the context of prototype vaccines, modified vaccines, and next generation vaccines.


Subject(s)
COVID-19 , Vaccines , COVID-19/prevention & control , COVID-19 Vaccines , Humans , SARS-CoV-2 , World Health Organization
14.
Vaccine ; 40(12): 1681-1690, 2022 03 15.
Article in English | MEDLINE | ID: mdl-35164990

ABSTRACT

Currently, no formal mechanisms or systematic approaches exist to inform developers of new vaccines of the evidence anticipated to facilitate global policy recommendations, before a vaccine candidate approaches regulatory approval at the end of pre-licensure efficacy studies. Consequently, significant delays may result in vaccine introduction and uptake, while post-licensure data are generated to support a definitive policy decision. To address the uncertainties of the evidence-to-recommendation data needs and to mitigate the risk of delays between vaccine recommendation and use, WHO is evaluating the need for and value of a new strategic alignment tool: Evidence Considerations for Vaccine Policy (ECVP). EVCPs aim to fill a critical current gap by providing early (pre-phase 3 study design) information on the anticipated clinical trial and observational data or evidence that could support WHO and/or policy decision making for new vaccines in priority disease areas. The intent of ECVPs is to inform vaccine developers, funders, and other key stakeholders, facilitating stakeholder alignment in their strategic planning for late stage vaccine development. While ECVPs are envisaged as a tool to support dialogue on evidence needs between regulators and policy makers at the national, regional and global level, development of an ECVP will not preclude or supersede the independent WHO's Strategic Advisory Group of Experts on Immunization (SAGE) evidence to recommendation (EtR) process that is required for all vaccines seeking WHO policy recommendation. Tuberculosis (TB) vaccine candidates intended for use in the adolescent and adult target populations comprise a portfolio of priority vaccines in late-stage clinical development. As such, TB vaccines intended for use in this target population provide a 'test case' to further develop the ECVP concept, and develop the first WHO ECVP considerations guidance.


Subject(s)
Tuberculosis Vaccines , Adolescent , Humans , Immunization Programs , Policy , Vaccination , World Health Organization
15.
Lancet HIV ; 399(10322): 406-410, jan 22. 2022. ilus
Article in English | RSDM | ID: biblio-1523707

ABSTRACT

In September, 2020, the WHO Prioritisation Roadmap for COVID-19 vaccines gave priority to prevention of severe disease and the highest risk groups. In July, 2021, the revised Roadmap noted that despite the progressive emergence of SARS-CoV-2 variants of concern, defined as mutations conferring increased infectivity, virulence, or relative capacity for immunological escape, vaccine effectiveness against severe disease had been retained.1 At the end of 2021, global differences in the inter-related variables of population seropositivity2 and vaccine coverage3 have widened, and omicron has been declared the fifth variant of concern.4 Omicron was detected in Africa,4 where successive waves of SARS-CoV-2 have resulted in prevalence of past infection higher than 80% in some regions5 and despite greatly increased global vaccine supplies,3 the average coverage that can be achieved there in 2021 is estimated to be only 17%.6 In 2022, we argue that COVID-19 vaccine strategies must remain focused on severe disease, and that global equity in achieving high adult coverage (ie, for those aged 18 years and older) of at least one dose is key to minimising severe COVID-19. The first four SARS-CoV-2 variants of concern were discovered in settings with high infection pressure before vaccines were available. The alpha variant of concern was detected in the UK, beta in South Africa, gamma in Brazil, and delta in India during the second half of 2020, but delta was not designated a variant of concern until May, 2021.7 The delta variant of concern has infectivity around three-fold greater than the other variants of concern, which were all more infectious than the Wuhan strain7 and by July, 2021, had attained global dominance.3 By contrast, the omicron variant of concern was first brought to attention by an outbreak among adults (ie, those younger than 30 years) in the South African province of Gauteng, a setting of high infectionacquired immunity following a third delta wave but low vaccine coverage in this age group


Subject(s)
Humans , Male , Female , Vaccination Coverage , COVID-19 Vaccines/administration & dosage , SARS-CoV-2/immunology , COVID-19/diagnosis , Global Health , Vaccine Efficacy , Health Priorities , Mozambique
16.
Clin Infect Dis ; 74(2): 227-236, 2022 01 29.
Article in English | MEDLINE | ID: mdl-33949661

ABSTRACT

BACKGROUND: Influenza vaccination is uncommon in low-resource settings. We evaluated aspects of operational feasibility of influenza vaccination programs targeting risk groups in the World Health Organization (WHO) African (AFR) and South-East Asian (SEAR) Regions. METHODS: We estimated routine immunization and influenza vaccination campaign doses, doses per vaccinator, and cold storage requirements for 1 simulated country in each region using evidence-based population distribution, vaccination schedule, and vaccine volumes. Influenza vaccination targeted persons <5 years, pregnant women, persons with chronic diseases, persons ≥65 years, and healthcare workers (HCW). For the AFR country, we compared vaccine volumes to actual storage capacities. RESULTS: Targeting HCW had a small operational impact, and subsequent findings exclude this group. During 3-month influenza vaccination campaigns, monthly doses delivered in the AFR country increased from 15.0% for ≥65 years to 93.1% for <5 years and in the SEAR country from 19.6% for pregnant women to 145.0% for persons with chronic diseases. National-level cold storage capacity requirements increased in the AFR country from 4.1% for ≥65 years to 20.3% for <5 years and in the SEAR country from 3.9% for pregnant women to 28.8% for persons with chronic diseases. Subnational-level cold storage capacity requirements increased in the AFR country from 5.9% for ≥65 years to 36.8% for <5 years and the SEAR country from 17.6% for pregnant women to 56.0% for persons with chronic diseases. CONCLUSIONS: Influenza vaccination of most risk groups will require substantial increases in doses, doses per vaccinator, and cold storage capacity in countries where infrastructure and resources are limited.


Subject(s)
Influenza Vaccines , Influenza, Human , Feasibility Studies , Female , Humans , Immunization Programs , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pregnancy , Seasons , Vaccination , World Health Organization
17.
Lancet ; 399(10323): 487-494, 2022 01 29.
Article in English | MEDLINE | ID: mdl-34902308

ABSTRACT

The Access to COVID-19 Tools Accelerator (ACT-A) is a multistakeholder initiative quickly constructed in the early months of the COVID-19 pandemic to respond to a catastrophic breakdown in global cooperation. ACT-A is now the largest international effort to achieve equitable access to COVID-19 health technologies, and its governance is a matter of broad public importance. We traced the evolution of ACT-A's governance through publicly available documents and analysed it against three principles embedded in the founding mission statement of ACT-A: participation, transparency, and accountability. We found three challenges to realising these principles. First, the roles of the various organisations in ACT-A decision making are unclear, obscuring who might be accountable to whom and for what. Second, the absence of a clearly defined decision making body; ACT-A instead has multiple centres of legally binding decision making and uneven arrangements for information transparency, inhibiting meaningful participation. Third, the nearly indiscernible role of governments in ACT-A, raising key questions about political legitimacy and channels for public accountability. With global public health and billions in public funding at stake, short-term improvements to governance arrangements can and should now be made. Efforts to strengthen pandemic preparedness for the future require attention to ethical, legitimate arrangements for governance.


Subject(s)
COVID-19/therapy , Clinical Governance/organization & administration , Global Health , International Cooperation , Pandemics/prevention & control , COVID-19/diagnosis , COVID-19/epidemiology , Decision Making, Organizational , Humans , Public Health Administration
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