Can live-attenuated SARS-CoV-2 vaccine contribute to stopping the pandemic?

Abstract

Coronavirus Disease 2019 (COVID-19) has plagued the world throughout 2020 to 2022, with over 580 million confirmed cases and 6.4 million deaths. Several vaccines have been approved for human use, including those from Pfizer-BioNTech, Moderna, Novavax, AstraZeneca, Johnson & Johnson, and Sinovac. The focus on rapid vaccine platforms such as mRNA, adenovirus vectors, DNA vectors, inactivated and subunit vaccines for COVID-19 [1] allowed the introduction of COVID-19 vaccines for human use in record time. These first-generation vaccines are major achievements, but improvements will be required to fully defeat this pandemic. In particular, new vaccines that deliver longer-lasting protection and provide broader immunity effective against current and future variants would be very valuable. Vaccines with a lengthy development pathway, such as the live-attenuated whole virus vaccines (LAVs) platform were largely overlooked in the race to develop a COVID-19 vaccine. A LAV is being developed by Codagenix in partnership with the Serum Institute of India and this single dose, intranasal vaccine has completed Phase I clinical trials, with promising safety and immunogenicity data There is a small number of other reported LAV that have shown utility in animal models of Although development of LAV is time-consuming, they have several important advantages that make this approach attractive. In this article, we discuss the arguments in support of LAV as COVID-19 vaccines, together with some of the challenges facing their development and use.