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The race for a vaccine against the coronavirus intensified on Monday as three competing laboratories released promising results from early trials in humans.
Now comes the hard part: proving that any of the vaccines protects against the virus, and establishing how much immunity they provide — and for how long.
“What this means is that each of these vaccines is worth taking all the way through to a Phase III study,” said Dr. Peter Jay Hotez, a vaccine researcher at the Baylor College of Medicine. “That is it. All it means is ‘worth pursuing.’” Phase III trials test how well a drug works.