# The Protective Efficacy of a SARS-CoV-2 Vaccine Candidate B.1.351V against Several Variant Challenges in K18-hACE2 Mice

## TL;DR

A SARS-CoV-2 vaccine candidate based on the B.1.351 variant shows strong protection against multiple virus variants in mice.

## Contribution

The study demonstrates the protective efficacy of the B.1.351V vaccine against multiple SARS-CoV-2 variants in a mouse model.

## Key findings

- The B.1.351V vaccine induced strong antibody responses against the B.1.351 virus and other variants in mice.
- Immunized mice showed high survival rates and minimal lung damage after viral challenge.
- The vaccine reduced virus copies in lung tissue and prevented weight loss in infected mice.

## Abstract

The emergence of SARS-CoV-2 variants of concern (VOCs) with increased transmissibility and partial resistance to neutralization by antibodies has been observed globally. There is an urgent need for an effective vaccine to combat these variants. Our study demonstrated that the B.1.351 variant inactivated vaccine candidate (B.1.351V) generated strong binding and neutralizing antibody responses in BALB/c mice against the B.1.351 virus and other SARS-CoV-2 variants after two doses within 28 days. Immunized K18-hACE2 mice also exhibited elevated levels of live virus-neutralizing antibodies against various SARS-CoV-2 viruses. Following infection with these viruses, K18-hACE2 mice displayed a stable body weight, a high survival rate, minimal virus copies in lung tissue, and no lung damage compared to the control group. These findings indicate that B.1.351V offered protection against infection with multiple SARS-CoV-2 variants in mice, providing insights for the development of a vaccine targeting SARS-CoV-2 VOCs for human use.