A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for the Medigen COVID-19 Protein Vaccine☆

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 protein subunit vaccines. This article uses the BRAVATO template to review the features of the MVC-COV1901 vaccine, a recombinant protein subunit vaccine based on the stabilized pre-fusion SARS-CoV-2 spike protein S-2P, adjuvanted with CpG 1018 and aluminum hydroxide, manufactured by Medigen Vaccine Biologics Corporation in Taiwan. MVC-COV1901 vaccine is indicated for active immunization to prevent COVID-19 caused by SARS-CoV-2 in individuals 12 years of age and older. The template offers details on basic vaccine information, target pathogen and population, characteristics of antigen and adjuvant, preclinical data, human safety and efficacy data, and overall benefit-risk assessment. The clinical development program began in September 2020 and based on demonstration of favorable safety and immunogenicity profiles in 11 clinical trials in over 5,000 participants, it has been approved for emergency use based on immunobridging results for adults in Taiwan, Estwatini, Somaliland, and Paraguay. The main clinical trials include placebo-controlled phase 2 studies in healthy adults (CT-COV-21), adolescents (CT-COV-22), and elderly population (CT-COV-23) as well as 3 immunobridging phase 3 trials (CT-COV-31, CT-COV-32, and CT-COV-34) in which MVC-COV1901 was compared to AZD1222. There are also clinical trials studying MVC-COV1901 as homologous and heterologous boosters (CT-COV-24 and CT-COV-25). The totality of evidence based on ∼3 million vaccinees to date includes a mostly clean safety profile, with adverse events mostly being mild and self-limiting in both clinical development and post-marketing experience, proven immunogenic response, and real-world effectiveness data. The immunogenic profile demonstrates that MVC-COV1901 induces high levels of neutralizing and binding antibodies against SARS-CoV-2. There is a dose-dependent response and a significant correlation between binding and neutralizing antibody activity. Antigen-specific T-cell responses, particularly a Th1-biased immune response characterized by high levels of interferon gamma and IL-2 cytokines, have also been observed. Coupled with this, MVC-COV1901 has favorable thermostability and better safety profiles when compared to other authorized vaccines from different platforms, which make it potentially a good candidate for vaccine supply chains in global markets.

A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for the Medigen COVID-19 protein vaccine.

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 protein subunit vaccines. This article uses the BRAVATO template to review the features of the MVC-COV1901 vaccine, a recombinant protein subunit vaccine based on the stabilized pre-fusion SARS-CoV-2 spike protein S-2P, adjuvanted with CpG 1018 and aluminum hydroxide, manufactured by Medigen Vaccine Biologics Corporation in Taiwan. MVC-COV1901 vaccine is indicated for active immunization to prevent COVID-19 caused by SARS-CoV-2 in individuals 12 years of age and older. The template offers details on basic vaccine information, target pathogen and population, characteristics of antigen and adjuvant, preclinical data, human safety and efficacy data, and overall benefit-risk assessment. The clinical development program began in September 2020 and based on demonstration of favorable safety and immunogenicity profiles in 11 clinical trials in over 5,000 participants, it has been approved for emergency use based on immunobridging results for adults in Taiwan, Estwatini, Somaliland, and Paraguay. The main clinical trials include placebo-controlled phase 2 studies in healthy adults (CT-COV-21), adolescents (CT-COV-22), and elderly population (CT-COV-23) as well as 3 immunobridging phase 3 trials (CT-COV-31, CT-COV-32, and CT-COV-34) in which MVC-COV1901 was compared to AZD1222. There are also clinical trials studying MVC-COV1901 as homologous and heterologous boosters (CT-COV-24 and CT-COV-25). The totality of evidence based on ∼3 million vaccinees to date includes a mostly clean safety profile, with adverse events mostly being mild and self-limiting in both clinical development and post-marketing experience, proven immunogenic response, and real-world effectiveness data. The immunogenic profile demonstrates that MVC-COV1901 induces high levels of neutralizing and binding antibodies against SARS-CoV-2. There is a dose-dependent response and a significant correlation between binding and neutralizing antibody activity. Antigen-specific T-cell responses, particularly a Th1-biased immune response characterized by high levels of interferon gamma and IL-2 cytokines, have also been observed. Coupled with this, MVC-COV1901 has favorable thermostability and better safety profiles when compared to other authorized vaccines from different platforms, which make it potentially a good candidate for vaccine supply chains in global markets.

Advancing the Science of Vaccine Safety During the Coronavirus Disease 2019 (COVID-19) Pandemic and Beyond: Launching an International Network of Special Immunization Services.

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.

Vaccines based on the replication-deficient simian adenoviral vector ChAdOx1: Standardized template with key considerations for a risk/benefit assessment.

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.

A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for an inactivated viral vaccine against Chikungunya virus.

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.

A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for the Moderna COVID-19 Vaccine (mRNA-1273).

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.

The critical role of background rates of possible adverse events in the assessment of COVID-19 vaccine safety.

Beginning in December of 2019, a novel coronavirus, SARS-CoV-2, emerged in China and is now a global pandemic with extensive morbidity and mortality. With the emergence of this threat, an unprecedented effort to develop vaccines against this virus began. As vaccines are now being introduced globally, we face the prospect of millions of people being vaccinated with multiple types of vaccines many of which use new vaccine platforms. Since medical events happen without vaccines, it will be important to know at what rate events occur in the background so that when adverse events are identified one has a frame of reference with which to compare the rates of these events so as to make an initial assessment as to whether there is a potential safety concern or not. Background rates vary over time, by geography, by sex, socioeconomic status and by age group. Here we describe two key steps for post-introduction safety evaluation of COVID-19 vaccines: Defining a dynamic list of Adverse Events of Special Interest (AESI) and establishing background rates for these AESI. We use multiple examples to illustrate use of rates and caveats for their use. In addition we discuss tools available from the Brighton Collaboration that facilitate case evaluation and understanding of AESI.

Suitability of databases in the Asia-Pacific for collaborative monitoring of vaccine safety.

INTRODUCTION: Information regarding availability of electronic healthcare databases in the Asia-Pacific region is critical for planning vaccine safety assessments particularly, as COVID-19 vaccines are introduced. This study aimed to identify data sources in the region, potentially suitable for vaccine safety surveillance. This manuscript is endorsed by the International Society for Pharmacoepidemiology (ISPE). METHODS: Nineteen countries targeted for database reporting were identified using published country lists and review articles. Surveillance capacity was assessed using two surveys: a 9-item introductory survey and a 51-item full survey. Survey questions related to database characteristics, covariate and health outcome variables, vaccine exposure characteristics, access and governance, and dataset linkage capability. Other questions collated research/regulatory applications of the data and local publications detailing database use for research. RESULTS: Eleven databases containing vaccine-specific information were identified across 8 countries. Databases were largely national in coverage (8/11, 73%), encompassed all ages (9/11, 82%) with population size from 1.4 to 52 million persons. Vaccine exposure information varied particularly for standardized vaccine codes (5/11, 46%), brand (7/11, 64%) and manufacturer (5/11, 46%). Outcome data were integrated with vaccine data in 6 (55%) databases and available via linkage in 5 (46%) databases. Data approval processes varied, impacting on timeliness of data access. CONCLUSIONS: Variation in vaccine data availability, complexities in data access including, governance and data release approval procedures, together with requirement for data linkage for outcome information, all contribute to the challenges in building a distributed network for vaccine safety assessment in the Asia-Pacific and globally. Common data models (CDMs) may help expedite vaccine safety research across the region.

Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) standardized template for collection of key information for benefit-risk assessment of live-attenuated viral vaccines.

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.

Vaccines based on replication incompetent Ad26 viral vectors: Standardized template with key considerations for a risk/benefit assessment.

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.

The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of viral vector vaccines.

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.

The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of inactivated viral vaccines.

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.

The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of protein vaccines.

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.

The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of nucleic acid (RNA and DNA) vaccines.

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.

Consensus summary report for CEPI/BC March 12-13, 2020 meeting: Assessment of risk of disease enhancement with COVID-19 vaccines.

A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of "disease enhancement" has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.