I don't expect the new mRNA to be injected in humans directly. I guess it will be tires in mice, then in other animals, then in a few humans, then in a bigger group, and then available to the general public. (Or something like that, I don't remember the details, IANAMD.)

It's the usual process for all new medicines. We already had a lot of bad cases with other potential medicines, so all new candidates must pass a lot of tests.