White House pressure for a vaccine raises risk the U.S. will approve one that doesnt work – POLITICO

Despite the pitfalls of drug development, manufacturers of potential coronavirus vaccines are pushing to accelerate the development timeline. Rather than beginning with preliminary studies in animals, companies are conducting the tests concurrently with early human trials which regulators have allowed because of the urgency of the situation.

Manufacturers are also merging clinical trials, which are typically done in three phases, and moving swiftly from one stage to another. Johnson & Johnson will begin testing its vaccine in people next month, in a study that will combine a phase one safety trial and a phase two efficacy trial. The company plans to start the final phase of testing, a phase three trial, by September.

Another vaccine, made by Moderna Therapeutics, is heading into final human trials in July. And a candidate from AstraZeneca and the University of Oxford is hot on its heels. A dozen more candidates are progressing through laboratory tests and early studies in people.

But those trials can only be accelerated so much. Moderna plans to enroll 30,000 people in its phase three studies, Fauci said and signing them all up could take the rest of the year.

Scientists are also now considering sometimes controversial methods, such as vaccinating healthy volunteers and then exposing them to the virus to see whether the vaccine works. That approach, known as a human challenge study, would need to be authorized by the FDA and overseen by an ethics committee.

Human challenge studies are tricky because scientists need to expose volunteers to just the right amount of the virus too much, and the vaccine could fail; too little, and the vaccines effectiveness could be overstated. But this type of study could fill in crucial data gaps if the U.S. outbreak shrinks before the first candidate vaccines enter phase three trials in the fall.

Its on the table. I hope we wont have to use it, said Fauci, noting that the method would not necessarily save time. We are making challenge doses. Were not saying were going to use them.

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White House pressure for a vaccine raises risk the U.S. will approve one that doesnt work - POLITICO