Last Updated May 15, 2020 7:06 PM EDT
The director of the National Institutes of Health (NIH) has said that no corners will be cut in. But now, there's encouraging news about a potential vaccine that's now being tested on humans and monkeys.
NIH researchers in Montana tested the vaccine using six rhesus macaque monkeys. They said the monkeys that got the vaccine developed protective antibodies against the coronavirus.
But it's what happened next that's giving doctors hope. When they exposed the animals to coronavirus, the monkeys that weren't vaccinated developed pneumonia, a sign of COVID-19. But those that got the vaccine, and developed the protective antibodies, had no pneumonia and no virus in their lungs.
"Why isn't it enough to show that a vaccine elicits, say, an antibody response?" asked CBS News chief medical correspondent Dr. Jon LaPook.
"We need to know that it protects the animal or the human from the infection," said Dr. Kathryn Edwards, who directs vaccine research at Vanderbilt University. "And just having the antibody, if it doesn't work to prevent disease, it's not going to cut it."
The vaccine used in the study is being. It relies on a cold virus that's been modified so it can't spread infection. The vaccine is packed with genetic material from the coronavirus — and once injected, it triggers an immune response, teaching the body to recognize and fight a future infection.
Oxford professor of human genetics Adrian Hill said that if it works, it has another important benefit. "This is not a hugely difficult vaccine to make," he said. "So large scale is feasible, we believe."
A different study has shown that rhesus monkeys and humans have about 93% of their DNA in common. But researchers won't be celebrating until there's a vaccine that's safe and effective in people.