Coronavirus Disease 2019 Vaccine Development: An Overview

An in-depth analysis of COVID-19 treatment: Present situation and prospects

Coronavirus disease 2019 (COVID-19) the most contagious infection caused by the unique type of coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), produced a global pandemic that wreaked havoc on the health-care system, resulting in high morbidity and mortality. Several methods were implemented to tackle the virus, including the repurposing of existing medications and the development of vaccinations. The purpose of this article is to provide a complete summary of the current state and future possibilities for COVID-19 therapies. We describe the many treatment classes, such as antivirals, immunomodulators, and monoclonal antibodies, that have been repurposed or developed to treat COVID-19. We also looked at the clinical evidence for these treatments, including findings from observational studies and randomized-controlled clinical trials, and highlighted the problems and limitations of the available evidence. Furthermore, we reviewed existing clinical trials and prospective COVID-19 therapeutic options, such as novel medication candidates and combination therapies. Finally, we discussed the long-term consequences of COVID-19 and the importance of ongoing research into the development of viable treatments. This review will help physicians, researchers, and policymakers to understand the prevention and mitigation of COVID-19.

Immune Stimulation with Imiquimod to Best Face SARS-CoV-2 Infection and Prevent Long COVID

Through widespread immunization against SARS-CoV-2 prior to or post-infection, a substantial segment of the global population has acquired both humoral and cellular immunity, and there has been a notable reduction in the incidence of severe and fatal cases linked to this virus and accelerated recovery times for those infected. Nonetheless, a significant demographic, comprising around 20% to 30% of the adult population, remains unimmunized due to diverse factors. Furthermore, alongside those recovered from the infection, there is a subset of the population experiencing persistent symptoms referred to as Long COVID. This condition is more prevalent among individuals with underlying health conditions and immune system impairments. Some Long COVID pathologies stem from direct damage inflicted by the viral infection, whereas others arise from inadequate immune system control over the infection or suboptimal immunoregulation. There are differences in the serum cytokines and miRNA profiles between infected individuals who develop severe COVID-19 or Long COVID and those who control adequately the infection. This review delves into the advantages and constraints associated with employing imiquimod in human subjects to enhance the immune response during SARS-CoV-2 immunization. Restoration of the immune system can modify it towards a profile of non-susceptibility to SARS-CoV-2. An adequate immune system has the potential to curb viral propagation, mitigate symptoms, and ameliorate the severe consequences of the infection.

Identifying a causal link between prolactin signaling pathways and COVID-19 vaccine-induced menstrual changes

COVID-19 vaccines have been instrumental tools in the fight against SARS-CoV-2 helping to reduce disease severity and mortality. At the same time, just like any other therapeutic, COVID-19 vaccines were associated with adverse events. Women have reported menstrual cycle irregularity after receiving COVID-19 vaccines, and this led to renewed fears concerning COVID-19 vaccines and their effects on fertility. Herein we devised an informatics workflow to explore the causal drivers of menstrual cycle irregularity in response to vaccination with mRNA COVID-19 vaccine BNT162b2. Our methods relied on gene expression analysis in response to vaccination, followed by network biology analysis to derive testable hypotheses regarding the causal links between BNT162b2 and menstrual cycle irregularity. Five high-confidence transcription factors were identified as causal drivers of BNT162b2-induced menstrual irregularity, namely: IRF1, STAT1, RelA (p65 NF-kB subunit), STAT2 and IRF3. Furthermore, some biomarkers of menstrual irregularity, including TNF, IL6R, IL6ST, LIF, BIRC3, FGF2, ARHGDIB, RPS3, RHOU, MIF, were identified as topological genes and predicted as causal drivers of menstrual irregularity. Our network-based mechanism reconstruction results indicated that BNT162b2 exerted biological effects similar to those resulting from prolactin signaling. However, these effects were short-lived and didn't raise concerns about long-term infertility issues. This approach can be applied to interrogate the functional links between drugs/vaccines and other side effects.

A systematic review of vaccine-induced thrombotic thrombocytopenia in individuals who received COVID-19 adenoviral-vector-based vaccines

Reports of thrombotic response after receiving COVID-19 Adenoviral-Vector Based Vaccines raise concerns about vaccine-induced thrombotic thrombocytopenia (VITT); therefore, we conduct this systematic review to report susceptible demographics outcomes, commonalities, and prognosis of reporting cases. We identified published articles by searching PubMed, SCOPUS, and Web of Science from December 2020 till May 2021, with an updated search in September 2021. All case reports and case series reporting thrombotic response after receiving COVID-19 Adenoviral-Vector Based Vaccines were eligible for including. In addition, two authors independently extracted data and assessed the quality of the included studies. A total of 157 patients with thrombotic events after the ChAdOx1 nCoV-19 vaccine and 16 patients with thrombotic events after Ad26.COV2. S vaccine was included in our study. 72% of the ChAdOx1 nCoV-19 cases were females, while in Ad26.COV2.S subgroup, all reported patients were females. The commonest presentations were deep vein thrombosis 20 (12.7%) and cerebral venous sinus thrombosis 18 (11.5%) in the ChAdOx1 nCoV-19 subgroup while cerebral venous sinus thrombosis 14 (87.5%) and pulmonary embolism 2 (12.5%) in the Ad26.COV2. S subgroup. In this study, we described the certain demographics associated with VITT and the clinical presentations of those cases in the ChAdOx1 nCoV-19 and Ad26.COV2. S vaccines. Young individuals, particularly females, may be more susceptible to VITT, and future studies should seek to confirm this association. In addition, the clinical presentation of VITT commonly includes cerebral thrombi, pulmonary embolism, and deep venous thrombosis, but other presentations are also possible, highlighting the importance of clinical vigilance in recent vaccine recipients.

A global survey in the developmental landscape of possible vaccination strategies for COVID-19

The development of COVID-19 vaccines was promptly regulated to ensure the best possible approach. By January 2022, 75 candidates reached preclinical evaluation in various animal models, 114 vaccines were in clinical trials on humans, and 48 were in the final testing stages. Vaccine platforms range from whole virus vaccines to nucleic acid vaccines, which are the most promising in prompt availability and safety. The USA and Europe have approved vaccines developed by Pfizer-BioNTech (BNT162b2) and Moderna (mRNa1273). So far, Pfizer-BioNTech, Moderna, Johnson & Johnson, AstraZeneca-University of Oxford, Sinopharm, Sinovac Biotech Gamaleya, Bharat Biotech, and Novavax have documented effective vaccines. Even with technological advances and a fast-paced development approach, many limitations and problems need to be overcome before a large-scale production of new vaccines can start. The Key is to ensure equal and fair distribution globally through regulatory measures. Recent studies link Bacillus Calmette-Guérin (BCG) vaccination programs and lower disease severity.

Immune-related therapeutics: an update on antiviral drugs and vaccines to tackle the COVID-19 pandemic

The coronavirus disease 2019 (COVID-19) pandemic rapidly spread globally. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes COVID-19, is a positive-sense single-stranded RNA virus with a reported fatality rate ranging from 1% to 7%, and people with immune-compromised conditions, children, and older adults are particularly vulnerable. Respiratory failure and cytokine storm-induced multiple organ failure are the major causes of death. This article highlights the innate and adaptive immune mechanisms of host cells activated in response to SARS-CoV-2 infection and possible therapeutic approaches against COVID-19. Some potential drugs proven to be effective for other viral diseases are under clinical trials now for use against COVID-19. Examples include inhibitors of RNA-dependent RNA polymerase (remdesivir, favipiravir, ribavirin), viral protein synthesis (ivermectin, lopinavir/ ritonavir), and fusion of the viral membrane with host cells (chloroquine, hydroxychloroquine, nitazoxanide, and umifenovir). This article also presents the intellectual groundwork for the ongoing development of vaccines in preclinical and clinical trials, explaining potential candidates (live attenuated-whole virus vaccines, inactivated vaccines, subunit vaccines, DNAbased vaccines, protein-based vaccines, nanoparticle-based vaccines, virus-like particles and mRNA-based vaccines). Designing and developing an effective vaccine (both prophylactic and therapeutic) would be a long-term solution and the most effective way to eliminate the COVID-19 pandemic.

Novel Strategies of Immunization against COVID-19

COVID-19 manifested itself as a global pandemic in 2019 but even in 2021, it is still not successfully contained. This virus has claimed millions of lives worldwide and rendered many more jobless. Apart from causing mild to severe pneumonia, the virus has also caused a loss of livelihood for thousands globally, along with widespread trauma and depression. Since the transmission rate of the virus is so high, temporary prophylaxis relied on sanitization, wearing masks and physical distancing. However, a long-term solution for stopping viral spread is vaccination. Apart from being the fastest way to induce immunity against the virus, vaccination is also the cheapest and most practical way. However, a vaccine can only be commercially available after it has passed through various clinical trial phases. So far, more than two hundred potential vaccine candidates underwent different phases of the clinical trial, and some of the front-runners have shown more than 90% efficacy. This review has compiled all such vaccine candidates, their types, their modes of action, and the associated pros and cons. The current advances in clinical trials of vaccines have also been discussed, such as plant-based and cocktail vaccines that have recently emerged. Nowadays, novel strains like Delta plus are also emerging and posing a threat. Thus, it is mandatory to get vaccinated and choose a vaccine that provides long-term protection against multiple strains.

Review of COVID-19 vaccine subtypes, efficacy and geographical distributions

As of 1 May 2021, there have been 152 661 445 Covid-19 cases with 3 202 256 deaths globally. This pandemic led to the race to discover a vaccine to achieve herd immunity and curtail the damaging effects of Covid-19. This study aims to discuss the most recent WHO-approved Covid-19 vaccine subtypes, their status and geographical scheduled updates as of 4 May 2021. The keywords "Covid-19, Vaccines, Pfizer, BNT162b2, AstraZeneca, AZD1222, Moderna, mRNA-1273, Janssen, Ad26.COV2.S" were typed into PubMed. Thirty Two relevant PubMed articles were included in the study. The vaccines discussed are Pfizer/BNT162b2, Moderna Vaccine/mRNA1273, AstraZeneca/AZD122/ChAdOx1 n-CoV-19 and the Janssen vaccines/Ad26.COV2.S, as well as their platforms, trials, limitations and geographical distributions. As of 16 May 2021, the number of countries that have approved the use of the following vaccines is Pfizer in 85, Moderna in 46, Oxford/AstraZeneca in 101, and Janssen in 41.

Review on Up-to-Date Status of Candidate Vaccines for COVID-19 Disease

The global pandemic of COVID-19 caused by SARS-CoV-2 continues to spread and poses serious threats to public health and economic stability throughout the world. Thus, to protect the global population, developing safe and effective vaccines is mandatory to control the spread of SARS-CoV-2 pandemic. Since genomic sequences of SARS-CoV-2 and SARS-CoV-1 have similarity and use the same receptor (ACE2), it is important to learn from the development of SARS-CoV-1 vaccines for the development of SARS-CoV-2 vaccines. Normally vaccine development takes 10-15 years but vaccine development against SARS-CoV2 is going on at a very fast pace resulting in almost breakthrough methods of vaccine development by several research institutions. The whole process of vaccine development including clinical trials gets shortened and may be fast tracked to 15-18 months. Global collaborations and increased research efforts among the scientific community have led to more than 214 candidate vaccines globally. The current review highlights the different approaches and technologies used around the world for the design and development of the vaccines and also focuses on the recent status of the SARS-CoV-2 vaccine candidates under development by various institutions to combat the world threat of COVID-19 pandemic.