Boston researchers develop vaccines that protect against COVID-19 in rhesus monkeys

Editor's Note

In this study, researchers from Beth Israel Deaconess Medical Center in Boston demonstrated that six candidate DNA vaccines induced neutralizing antibody responses and protected against SARS-CoV-2 in rhesus monkeys.

For the study, researchers immunized 25 adult rhesus monkeys with the investigational vaccines, and 10 animals received a sham control.

Animals that received the vaccines developed neutralizing antibodies against the virus. Three weeks after a boost vaccination, all 35 animals were exposed to the virus.

Follow-up testing found dramatically lower viral loads in animals that received the vaccines compared to controls. Eight of the 25 vaccinated animals demonstrated no detectable virus at any point after exposure to the virus, and the other 17 showed low levels of virus.

Overall, higher antibody levels were linked to lower viral loads, suggesting that neutralizing antibodies may serve as a correlate of protection and may be useful as a benchmark in clinical testing of SARS-CoV-2 vaccines in humans, the researchers say.