All the sites where the testing is being done are put ON HOLD. So much for operation blue streak. So much for operation fast tracking. They might pick up and go on after they determine why the adverse reaction occurred. Or they could JUNK THE ENTIRE THING and start over again.
This will happen a lot. Even when they are on the verge of finishing the stages of testing they might have to JUNK IT.
The dipstick counts his chickens before they're hatched. He says it shall be thus and so and by gawd it better be thus and so OR he will have a hissy fit tantrum meltdown and start breaking things.