Scientists at the National Institutes of Health are working with a biotech company to quickly start clinical trials of an experimental messenger RNA vaccine and fast track it to licensure. 1 The FDA has not yet licensed messenger RNA vaccines that use part of the RNA of a virus to manipulate the body's immune system into stimulating a potent immune response. 2 3  It looks like the coronavirus vaccine will be the first genetically engineered messenger RNA vaccine to be fast tracked to licensure, just like Gardasil was the first genetically engineered virus-like particle vaccine to be fast tracked to licensure. 4 5

There likely will be lots of questions about whether the fast tracked coronavirus vaccine was studied long enough to adequately demonstrate safety, especially for people who have trouble resolving strong inflammatory responses in their bodies and may be at greater risk for vaccine reactions.