Home-made monkeypox mRNA shots prove effective: study

A China-developed monkeypox-specific mRNA vaccines have proved highly effective in protecting mice from a lethal dose of the virus, making them a potential candidate to help prepare the world for monkeypox outbreaks in the future, according to a study released recently by the China National Biotec Group (CNBG) under Chinese state-owned Sinopharm.

The study, posted on bioRxiv on Tuesday, is believed to be the world’s first released study on monkeypoxspecific mRNA vaccines.

The study results showed the novel mRNA vaccines expressing a fusion protein composed of a truncated form of A35R and a full-length M1R can provide strong immunity and protection against the poxvirus.

The vaccines can effectively induce both humoral and cellular immunity against the virus, demonstrating complete protection for the mice with lethal vaccinia virus challenge. Given the high homology of vaccinia and monkeypox, the results suggest that VGPox can be a potential mRNA vaccine against monkeypox, the study concluded.

Monkeypox virus belongs to the Orthopoxvirus genus of the Poxviridae family, which also includes variola virus (smallpox) and vaccinia virus.

Outbreaks of the variola virus caused millions of deaths in the world until its global eradication in 1980, thanks to the worldwide vaccination with live virus preparations of the infectious vaccinia viruses.

This year witnessed an increase in cases of monkeypox infections worldwide leading to a global outbreak, which was declared by the World Health Organization on July 23 as a global health emergency.

According to the US Centers for Disease Control and Prevention, a total of 80,850 monkeypox cases had been reported around the world as of Wednesday.

The end of smallpox vaccination might be one of the reasons causing the current outbreak of monkeypox virus since the two viruses share highly homologous genomes and their antibodies have showed significant cross-protection.

In comparison with the attenuated virus vaccines, the CNBG monkeypox-specific mRNA vaccines prove safer to recipients.

The study showed that mice in all mRNA vaccine groups had no body weight loss or other abnormality after they were intranasally challenged with a lethal dose vaccinia virus, the study showed.