May 20, 2020
Coronavirus Vaccine Research Shows Promise In Rhesus Monkey Trials

Another piece of good news emerged today in the quest for a coronavirus vaccine, as researchers announced that a new prototype was successful in protecting rhesus monkeys from COVID-19. The encouraging new findings were based on two different studies, both published in Science Magazine.

"To me, this is convincing that a vaccine is possible," said Dr. Nelson Michael, director of the Center for Infectious Diseases Research at Walter Reed Army Institute of Research, per

The study, spearheaded by Dr. Dan Barouch, a virologist at Beth Israel Deaconess Medical Center in Boston, originally began as a way to confirm that monkeys — and potentially humans — would become immune to the virus after contracting the disease.

The team injected nine unvaccinated rhesus monkeys with the coronavirus. The animals quickly developed symptoms of the illness, such as lung inflammation and pneumonia.

After the monkeys began to recover, scientists noted that their bodies had made antibodies against the virus, including "neutralizing" antibodies, which provide immunization from the disease.

A little over a month after the monkeys had recovered, scientists subjected the animals to the virus once more. Though the coronavirus was able to lodge into their noses for a short period of time, the monkeys quickly began producing the neutralizing antibodies, soon extinguishing all traces of the illness.

Following the development of the successful neutralizing antibodies, Barouch and his team then began injecting previously untested monkeys with the DNA that would help them develop the same protection despite no previous exposure to the coronavirus.

Not all the monkeys were injected with the same formula in order to help scientists further understand the best way of attacking the virus.

covid testing tube
Getty Images | Andressa Anholete

After letting the animals develop immunity over the course of three weeks, researchers then sprayed the virus into their noses.

All the monkeys displayed some form of a protected immune system, with some variations more effective than others. Moreover, in eight of the rhesus monkeys, scientists could not detect the virus at all.

"I think that overall this will be seen as very good news for the vaccine effort," Barouch said. "This increases our optimism that a vaccine for COVID-19 will be possible."

"This is something that would protect you from disease," added Florian Krammer, a virologist at the Icahn School of Medicine at Mount Sinai in New York who was not involved in the study.

"It's not perfect, but you certainly see protection," he concluded.

These findings piggyback off a recent announcement from Massachusetts-based bio company Moderna, which claimed on Monday morning that the first trial of its vaccine prototype tested on humans had been successful.