New trivalent vaccine offers protection against multiple highly pathogenic coronaviruses

In a significant leap forward in the battle against deadly coronaviruses, a team of researchers has unveiled a trivalent vaccine designed to protect against not one, not two, but three highly pathogenic human coronaviruses.

Existing SARS-CoV-2 vaccines have been instrumental in mitigating the spread of COVID-19 and reducing the severity of the disease. However, they primarily target the specific strain of the virus responsible for the ongoing pandemic, SARS-CoV-2, leaving potential gaps in protection against other related viruses. These vaccines do not offer defense against other sarbecoviruses or merbecoviruses.

The breakthrough comes in the form of a trivalent sortase-conjugate nanoparticle (scNP) vaccine. This innovative vaccine contains receptor-binding domains (RBDs) from three different coronaviruses - SARS-CoV-2, RsSHC014, and MERS-CoV. The vaccine has been found to induce the production of live-virus neutralizing antibodies, a crucial factor in the immune response against these pathogens.

Notably, the trivalent RBD scNP vaccine proved highly effective in a series of tests involving mice, demonstrating its ability to elicit serum neutralizing antibodies against various lethal coronaviruses, including bat zoonotic Wuhan Institute of Virology-1 (WIV-1)-CoV, SARS-CoV, SARS-CoV-2 BA.1, SARS-CoV-2 XBB.1.5, and MERS-CoV.

While a monovalent vaccine targeting just the SARS-CoV-2 RBD scNP offered protection against Sarbecovirus challenge, the trivalent version showed its remarkable strength by safeguarding against both Merbecovirus and Sarbecovirus challenge, even in highly pathogenic and lethal mouse models.

Reference: Martinez et al., Vaccine-mediated protection against Merbecovirus and Sarbecovirus challenge in mice, Cell Reports (2023), https://doi.org/10.1016/j.celrep.2023.113248