Evolving potential vaccine candidates amid COVID-19 pandemic: Pipeline to Lifeline

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is globally explored to decode its genomic functionality along with elucidating immunogenic pathways to design and develop an efficient vaccine. Potential immunogenic targets have been screened and validated through preclinical evaluation using experimental models. Computational platform and molecular docking studies are also being conducted to study the immunodynamic mechanisms which involve suitable epitopes of host target cells that respond to the potential vaccine candidate eliciting an immune-mediated reaction. Although SARS-CoV-2 possesses genetic similarities with previously known human coronaviruses, the emergence of novel mutational changes in the immunodominant region of the receptor-binding domain of viral spike protein resulted in high transmissibility and fatality. On a periodical basis, the World Health Organization (WHO) publishes the update on evolving vaccine candidates and encouraging several vaccine developers including multinational companies to join the worldwide campaign against the COVID-19 pandemic. As per the latest WHO landscape draft of evolving vaccine candidates, around 180 teams with respective vaccine candidates across the world are working by utilizing multiple developmental platforms, out of which 35 candidates have entered clinical phase trial and 145 candidates are under the preclinical phase of evaluation. They are also being tested for undesired immunopotentiation without compromising their safety and efficacy. These vaccine candidates along with their advantages and various challenges have been reviewed in this article.