COVID-19 Vaccines: Current Understanding on Immunogenicity, Safety, and Further Considerations

The world has entered the second wave of the COVID-19 pandemic, and its intensity is significantly higher than that of the first wave of early 2020. Many countries or regions have been forced to start the second round of lockdowns. To respond rapidly to this global pandemic, dozens of COVID-19 vaccine candidates have been developed and many are undergoing clinical testing. Evaluating and defining effective vaccine candidates for human use is crucial for prioritizing vaccination programs against COVID-19. In this review, we have summarized and analyzed the efficacy, immunogenicity and safety data from clinical reports on different COVID-19 vaccines. We discuss the various guidelines laid out for the development of vaccines and the importance of biological standards for comparing the performance of vaccines. Lastly, we highlight the key remaining challenges, possible strategies for addressing them and the expected improvements in the next generation of COVID-19 vaccines.

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Informed consent and informed intervention: SARS-CoV-2 vaccinations not just call for disclosure of newly emerging safety data but also for hypothesis generation and testing

European Journal of Medical Research ◽

10.1186/s40001-021-00558-y ◽

2021 ◽

Vol 26 (1) ◽

Author(s):

Johannes C. Fischer ◽

Albrecht G. Schmidt ◽

Edwin Bölke ◽

Verena Keitel ◽

Torsten Feldt ◽

...

Keyword(s):

Health Care ◽

Health Care Providers ◽

Viral Infections ◽

Safety Data ◽

Hypothesis Generation ◽

Care Providers ◽

Vaccination Programs ◽

Major Threat ◽

The World ◽

Population Scale

Abstract Background COVID-19 infection is a major threat to patients and health care providers around the world. One solution is the vaccination against SARS-CoV-2. Methods We performed a comprehensive query of the latest publications on the prevention of viral infections including the recent vaccination program and its side effects. Results The situation is evolving rapidly and there is no reasonable alternative to population-scale vaccination programs as currently enrolled. Conclusion Therefore, regulatory authorities should consider supplementing their conventional mandate of post-approval pharmacovigilance, which is based on the collection, assessment, and regulatory response to emerging safety findings.

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SARS-CoV-2 vaccines strategies: a comprehensive review of phase 3 candidates

npj Vaccines ◽

10.1038/s41541-021-00292-w ◽

2021 ◽

Vol 6 (1) ◽

Cited By ~ 3

Author(s):

Nikolaos C. Kyriakidis ◽

Andrés López-Cortés ◽

Eduardo Vásconez González ◽

Alejandra Barreto Grimaldos ◽

Esteban Ortiz Prado

Keyword(s):

Neutralizing Antibodies ◽

Large Scale ◽

Vaccine Development ◽

Rna Virus ◽

Protein S ◽

Effective Vaccine ◽

Phase 3 ◽

Vaccine Candidates ◽

Advantages And Disadvantages ◽

The World

AbstractThe new SARS-CoV-2 virus is an RNA virus that belongs to the Coronaviridae family and causes COVID-19 disease. The newly sequenced virus appears to originate in China and rapidly spread throughout the world, becoming a pandemic that, until January 5th, 2021, has caused more than 1,866,000 deaths. Hence, laboratories worldwide are developing an effective vaccine against this disease, which will be essential to reduce morbidity and mortality. Currently, there more than 64 vaccine candidates, most of them aiming to induce neutralizing antibodies against the spike protein (S). These antibodies will prevent uptake through the human ACE-2 receptor, thereby limiting viral entrance. Different vaccine platforms are being used for vaccine development, each one presenting several advantages and disadvantages. Thus far, thirteen vaccine candidates are being tested in Phase 3 clinical trials; therefore, it is closer to receiving approval or authorization for large-scale immunizations.

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EMERGENCE OF SECOND WAVE OF SARS-COV-2 INFECTIONS DURING THE ONGOING COVID-19 PANDEMIC: A MINI REVIEW

Journal of Experimental Biology and Agricultural Sciences ◽

10.18006/2020.8(spl-1-sars-cov-2).s57.s65 ◽

2020 ◽

Vol 8 (Spl-1-SARS-CoV-2) ◽

pp. S57-S65

Author(s):

Bhumika Prajapati ◽

◽

Kranti Suresh Vora ◽

Zareena Fathah ◽

Ranjit Sah ◽

...

Keyword(s):

Epidemic Curve ◽

Exponential Increase ◽

Global Pandemic ◽

The World ◽

Type 3 ◽

Second Wave ◽

Vulnerable Elderly ◽

Future Plans

The COVID-19 outbreak originated from Wuhan, China has spread over the world, causing a “Global Pandemic”. We analyzed daily confirmed cases and deaths from different countries to understand the progression of the ongoing pandemic in different parts around the world. The data indicated that the pandemic is in different stages in different countries, where they are either at the end of the second wave or middle or early phase of it or still in the middle of the first wave of infection, and they can be divided into four groups. Type 1 countries such as UK, France, Spain, and the Netherlands are currently witnessing the second wave of infection with an exponential increase in daily cases. Countries such as Australia, United States, Japan, and Poland are currently in the declining stage of second-wave, grouped as Type 2 countries. Type 3 countries such as Germany, Italy, Belgium, and Russia are recently seeing the second wave with slowly rising of confirmed cases. Type 4 countries including India, Brazil, Argentina, and Mexico are currently fighting against the first wave of COVID-19. These countries have a chance to learn from the countries which have overcome the second wave successfully. To be ahead of the epidemic curve and preventing it, countries need to make future plans on family, hospital, and community levels. Isolation of the highly vulnerable elderly people and young children, preventing social or public gathering, following the guidelines of COVID-19 prevention including wearing face masks regularly can save countries from devastating effects of the second wave of pandemic COVID-19.

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Infection and vaccine-induced neutralizing antibody responses to the SARS-CoV-2 B.1.617.1 variant

10.1101/2021.05.09.443299 ◽

2021 ◽

Author(s):

Venkata-Viswanadh Edara ◽

Lilin Lai ◽

Malaya Sahoo ◽

Katharine Floyd ◽

Mamdouh Sibai ◽

...

Keyword(s):

Protective Immunity ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Live Virus ◽

Global Pandemic ◽

Virus Assay ◽

Recent Emergence ◽

The World ◽

Antibody Resistance ◽

Second Wave

SARS-CoV-2 has caused a devastating global pandemic. The recent emergence of SARS-CoV-2 variants that are less sensitive to neutralization by convalescent sera or vaccine-induced neutralizing antibody responses has raised concerns. A second wave of SARS-CoV-2 infections in India is leading to the expansion of SARS-CoV-2 variants. The B.1.617.1 variant has rapidly spread throughout India and to several countries throughout the world. In this study, using a live virus assay, we describe the neutralizing antibody response to the B.1.617.1 variant in serum from infected and vaccinated individuals. We found that the B.1.617.1 variant is 6.8-fold more resistant to neutralization by sera from COVID-19 convalescent and Moderna and Pfizer vaccinated individuals. Despite this, a majority of the sera from convalescent individuals and all sera from vaccinated individuals were still able to neutralize the B.1.617.1 variant. This suggests that protective immunity by the mRNA vaccines tested here are likely retained against the B.1.617.1 variant. As the B.1.617.1 variant continues to evolve, it will be important to monitor how additional mutations within the spike impact antibody resistance, viral transmission and vaccine efficacy.

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Recent patents in dengue disease management

Pharmaceutical Patent Analyst ◽

10.4155/ppa-2020-0012 ◽

2020 ◽

Vol 9 (6) ◽

pp. 173-185

Author(s):

Sukhbir K Shahid

Keyword(s):

Disease Management ◽

Antiviral Drug ◽

Health Concern ◽

Effective Vaccine ◽

Vaccine Candidates ◽

Dengue Disease ◽

The World ◽

Current Article ◽

Dengue Control ◽

World Development

Dengue, an illness caused by four serotypes of the dengue virus is most prevalent in Asia and Latin America. Its manifestation varies from asymptomatic cases to severe forms and even deaths and is a growing health concern. Despite attempts to curtail it, the infection continues to intensify in endemic areas and spread to new areas of the world. Development of a safe and effective vaccine and a potent antiviral drug is ongoing but so far there has been no breakthrough. Nonetheless, researchers are carrying out studies with newer vaccine candidates and antiviral moieties, and some of these hold promise for the future. The current article describes the recent patents targeted at dengue control.

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Will vaccination refusal prolong the war on SARS-CoV-2?

Postgraduate Medical Journal ◽

10.1136/postgradmedj-2020-138903 ◽

2020 ◽

pp. postgradmedj-2020-138903

Author(s):

Robert Marcec ◽

Matea Majta ◽

Robert Likic

Keyword(s):

Herd Immunity ◽

Opinion Survey ◽

Safety And Efficacy ◽

Vaccine Candidates ◽

Public Opinion Survey ◽

Vaccination Response ◽

Global Pandemic ◽

Survey Results ◽

Human Use ◽

Novel Coronavirus

IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus that appeared in Wuhan, China in January 2020 and caused a global pandemic drastically changing everyday life. Currently, there are vaccine candidates in clinical trials and development, so it is only a matter of time before one is authorised for human use.Materials and methodsWe collected public opinion survey results about attitudes towards SARS-CoV-2 vaccination conducted in 2020 in 26 European countries.ResultsThe pooled surveys were conducted on a total of 24 970 participants; on average only 58% (n=14 365/24 970) of responders across Europe were willing to get a SARS-CoV-2 vaccine once it becomes available, 16% (n=3998/24 970) were neutral, and 26% (n=6607/24 970) were not planning to vaccinate against SARS-CoV-2. Such a low vaccination response could make it exceedingly difficult to reach the herd immunity threshold for SARS-CoV-2 through vaccination.ConclusionIt is very important to start conducting educational public health activities on the topic of vaccination as soon as possible, before a vaccine becomes available, in order to improve attitudes towards SARS-CoV-2 vaccination. Only by educating the general public about the benefits, safety and efficacy of vaccines can we hope to avoid the unnecessary prolongation of the COVID-19 pandemic.

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Analysis of non-pharmaceutical interventions and their impacts on COVID-19 in Kerala

Scientific Reports ◽

10.1038/s41598-021-04488-x ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

Elizabeth Goult ◽

Shubha Sathyendranath ◽

Žarko Kovač ◽

Christina Eunjin Kong ◽

Petar Stipanović ◽

...

Keyword(s):

Drug Therapy ◽

Retrospective Analysis ◽

The State ◽

Effective Vaccine ◽

International Media ◽

South Indian ◽

The World ◽

Indian State ◽

Second Wave ◽

Pharmaceutical Interventions

AbstractIn the absence of an effective vaccine or drug therapy, non-pharmaceutical interventions are the only option for control of the outbreak of the coronavirus disease 2019, a pandemic with global implications. Each of the over 200 countries affected has followed its own path in dealing with the crisis, making it difficult to evaluate the effectiveness of measures implemented, either individually, or collectively. In this paper we analyse the case of the south Indian state of Kerala, which received much attention in the international media for its actions in containing the spread of the disease in the early months of the pandemic, but later succumbed to a second wave. We use a model to study the trajectory of the disease in the state during the first four months of the outbreak. We then use the model for a retrospective analysis of measures taken to combat the spread of the disease, to evaluate their impact. Because of the differences in the trajectory of the outbreak in Kerala, we argue that it is a model worthy of a place in the discussion on how the world might best handle this and other, future, pandemics.

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COVID-19 in Kerala: analysis of measures and impacts

10.21203/rs.3.rs-75759/v1 ◽

2020 ◽

Author(s):

Elizabeth Goult ◽

Shubha Sathyendranath ◽

Žarko Kovač ◽

Anas Abdulaziz ◽

Nandini Menon ◽

...

Keyword(s):

Drug Therapy ◽

Retrospective Analysis ◽

The State ◽

Effective Vaccine ◽

International Media ◽

South Indian ◽

The World ◽

Indian State ◽

Second Wave ◽

Pharmaceutical Interventions

Abstract In the absence of an effective vaccine or drug therapy, non-Pharmaceutical Interventions are the only option for control of the outbreak of the coronavirus disease 2019, a pandemic with global implications. Each of the over 200 countries affected1 has followed its own path in dealing with the crisis, making it difficult to evaluate the effectiveness of measures implemented, either individually, or collectively. In this paper we analyse the case of the south Indian state of Kerala, which received much praise in the international media for its success in containing the spread of the disease in the early months of the pandemic, but is now in the grips of a second wave. We use a model to study the trajectory of the disease in the state during the first four months of the outbreak. We then use the model for a retrospective analysis of measures taken to combat the spread of the disease, to evaluate their impact. Because of the unusual aspects of the Kerala case, we argue that it is a model worthy of a place in the discussion on how the world might best handle this and other, future, pandemics.

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Heterologous prime-boost immunizations with chimpanzee adenoviral vectors elicit potent and protective immunity against SARS-CoV-2 infection

Cell Discovery ◽

10.1038/s41421-021-00360-4 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Jiaojiao Liu ◽

Kun Xu ◽

Man Xing ◽

Yue Zhuo ◽

Jingao Guo ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Immune Cell ◽

Protective Efficacy ◽

Effective Vaccine ◽

Vaccine Candidates ◽

Cell Responses ◽

Global Pandemic ◽

Specific Memory ◽

Boost Immunization ◽

Protective Antibodies

AbstractA safe and effective vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is urgently needed to tackle the COVID-19 global pandemic. Here, we describe the development of chimpanzee adenovirus serotypes 6 and 68 (AdC6 and AdC68) vector-based vaccine candidates expressing the full-length transmembrane spike glycoprotein. We assessed the vaccine immunogenicity, protective efficacy, and immune cell profiles using single-cell RNA sequencing in mice. Mice were vaccinated via the intramuscular route with the two vaccine candidates using prime-only regimens or heterologous prime-boost regimens. Both chimpanzee adenovirus-based vaccines elicited strong and long-term antibody and T cell responses, balanced Th1/Th2 cell responses, robust germinal center responses, and provided effective protection against SARS-CoV-2 infection in mouse lungs. Strikingly, we found that heterologous prime-boost immunization induced higher titers of protective antibodies, and more spike-specific memory CD8+ T cells in mice. Potent neutralizing antibodies produced against the highly transmissible SARS-CoV-2 variants B.1.1.7 lineage (also known as N501Y.V1) and B.1.351 lineage (also known as N501Y.V2) were detectable in mouse sera over 6 months after prime immunization. Our results demonstrate that the heterologous prime-boost strategy with chimpanzee adenovirus-based vaccines is promising for further development to prevent SARS-CoV-2 infection.

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The COVID-19 Vaccines: Recent Development, Challenges and Prospects

Vaccines ◽

10.3390/vaccines9040349 ◽

2021 ◽

Vol 9 (4) ◽

pp. 349

Author(s):

Yuxin Yan ◽

Yoongxin Pang ◽

Zhuoyi Lyu ◽

Ruiqi Wang ◽

Xinyun Wu ◽

...

Keyword(s):

Clinical Trials ◽

Severe Acute Respiratory Syndrome ◽

World Population ◽

Advanced Stage ◽

Vaccine Candidates ◽

Stage Of Development ◽

Global Pandemic ◽

The World ◽

Hygienic Measures ◽

Repurposed Drugs

The highly infectious coronavirus disease 2019 (COVID-19) associated with the pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread to become a global pandemic. At present, the world is relying mainly on containment and hygiene-related measures, as well as repurposed drugs to control the outbreak. The development of COVID-19 vaccines is crucial for the world to return to pre-pandemic normalcy, and a collective global effort has been invested into protection against SARS-CoV-2. As of March 2021, thirteen vaccines have been approved for application whilst over 90 vaccine candidates are under clinical trials. This review focuses on the development of COVID-19 vaccines and highlights the efficacy and vaccination reactions of the authorised vaccines. The mechanisms, storage, and dosage specification of vaccine candidates at the advanced stage of development are also critically reviewed together with considerations for potential challenges. Whilst the development of a vaccine is, in general, in its infancy, current progress is promising. However, the world population will have to continue to adapt to the “new normal” and practice social distancing and hygienic measures, at least until effective vaccines are available to the general public.

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