Click here for Logical Analysis ReportOp-ed:
From our analysis, we found the following most relevant:I would be much more comfortable with SARS data."
Petrovsky said that while RNA vaccines are very fast to make, evidence that they are going to work is scant.
"In the past, we've seen they have poor immunogenicity, which means they don't stimulate the immune system very well," he said.
Said Zaks: "We've demonstrated the utility to generate the right kind of immune response time and again in multiple phase one trials."
The challenge of a dangerous phenomenon
One frequent hurdle for vaccine developers is a phenomenon known as disease enhancement, in which the vaccine actually promotes the infection and makes the disease worse.
"The worst possible thing you do is vaccinate somebody to prevent infection and actually make them worse," Fauci said at a White House briefing last month.
This phenomenon underscores the importance of animal trials, experts say.
This is what happens when coronavirus research funding gets political
Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine, worked on development of a vaccine for SARS. Some of the animals he vaccinated wound up sicker than the ones he didn't vaccinate, once they were exposed to the virus.
He told Reuters that he believes the Moderna trial should conduct animal studies prior to injecting the vaccine in humans.
"If there is immune enhancement in laboratory animals vaccinated with the Moderna vaccine, that's a showstopper," he told the news organization.
A Moderna spokesperson said the company has not seen signs of enhanced disease in animal trials with the MERS vaccine that it was developing with NIH.
"Enhanced disease is a clinical finding that is very rarely seen," she said in an email.
Potential setbacks fall into two broad categories: the vaccine isn't strong enough to produce an immune response or the vaccine causes safety issues.
"It's possible there's no actual production of antibodies, in which because either the mRNA didn't get into the cells, the cells didn't make the proteins from the mRNA or the immune system didn't recognize those proteinsIndeed, it took just 42 days, as Bancel told Trump.
Officials with the National Institutes of Health are bullish.
Lead scientist says coronavirus vaccine could be ready soon
Lead scientist says coronavirus vaccine could be ready soon 01:35
"A lot of our work that we've done previously has essentially driven us into what we call a rapid response," said Dr. Kizzmekia Corbett, the lead scientist for coronavirus research at the National Institutes of Health, in a recent interview with CNN's Anderson Cooper and Dr. "The really interesting part about this is that we have a collaboration with Moderna," she added.
The National Institute of Allergy and Infectious Diseases -- a branch of the NIH -- said Moderna's vaccine platform is well-suited for responding to emerging outbreaks such as novel coronaviruses.
It "can be produced more quickly than with many other vaccine platforms," the NIAID said in an emailed statementIf the FDA's evaluation of these data support initiating human studies of a candidate coronavirus vaccine without first completing additional toxicology studies, then the FDA would consider allowing such human studies to proceed."
Petrovsky also noted that while NIH and Moderna worked on a MERS vaccine, they hadn't collaborated on a SARS (Severe Acute Respiratory Syndrome) vaccine