Adenoviral vector vaccine platforms in the SARS-CoV-2 pandemic

Abstract

Adenoviral vectors have been explored as vaccine agents for a range of infectious diseases, and their ability to induce a potent and balanced immune response made them logical candidates to apply to the COVID-19 pandemic. The unique molecular characteristics of these vectors enabled the rapid development of vaccines with advanced designs capable of overcoming the biological challenges faced by early adenoviral vector systems. These successes and the urgency of the COVID-19 situation have resulted in a flurry of candidate adenoviral vector vaccines for COVID-19 from both academia and industry. These vaccines represent some of the lead candidates currently supported by Operation Warp Speed and other government agencies for rapid translational development. This review details adenoviral vector COVID-19 vaccines currently in human clinical trials and provides an overview of the new technologies employed in their design. As these vaccines have formed a cornerstone of the COVID-19 global vaccination campaign, this review provides a full consideration of the impact and development of this emerging platform.

Factors Influencing Vaccine Hesitancy in China: A Qualitative Study

“…Based on the successful stories of smallpox eradication achieved by means of the vaccinia vaccine [2], heavy expectations have been placed on vaccines to suppress the COVID-19 pandemic. Unfortunately, although COVID-19 vaccines have been developed [3], its application in some countries is not promising [4,5]. Meanwhile, vaccine-preventable diseases have been resurging owing to the ever-growing anti-vaccination movement [6].…”

HEK293 Cell Line as a Platform to Produce Recombinant Proteins and Viral Vectors

“…Although the use of AdVs in gene therapies have declined due to this unfortunate incident, AdVs have seen a resurgent use in applications where an immunological response is desired. The capacity to induce a strong immune response has led to the development of vaccine candidates for infectious diseases and cancer immunotherapies ( Mendonça et al, 2021 ). AdVs now constitute majority of viral vectors in clinical trials with its predominant application as vaccines or in cancer therapies ( Bulcha et al, 2021 ).…”

“…The COVID-19 pandemic drove the rapid development of adenoviral vectored vaccines and their eventual emergency use ( Mendonça et al, 2021 ). Of the three adenoviral vectored vaccines approved for emergency use by the World Health Organisation (as of August 2021), Ad5-nCOV( Zhu et al, 2020 ) and ChAdOX1-nCoV ( Doremalen et al, 2020 ) are produced in HEK293 cells, while Ad26.…”

Can the Nasal Cavity Help Tackle COVID-19?

“…The vaccine is developed by Precision Virologics, a startup incubated at the Washington University School of Medicine (St Louis, MI, USA) in collaboration with Bharat Biotech International Limited (Hyderabad, India), which has already marketed IM COVID-19 vaccine named Covaxin TM (BBV152). In a study using a murine model for SARS-CoV-2 infection, intranasal administration of the vaccine was followed by a strong mucosal immune response preventing respiratory tract infection and inflammation [61,62]. To compare the efficacy of nasally delivered ChAd-SARS-CoV-2 vectors with IM administration, the vaccine was tested on a Syrian hamster model.…”