And then, finally, we’ve been working with the manufacturers around the quality of their manufacturing, the consistency of it. So that if a vaccine were to be authorized or approved, we could immediately know that quality manufacturing is in place. And again, that process normally takes months.
The last thing to mention is that there’s been manufacturing done at risk, meaning that companies have started manufacturing their vaccines [before the trials are complete], so that if an authorization or approval occurs, the vaccine is ready to go. And as you can see, this really shrinks the development time. But all the steps necessary to ensure safety and efficacy have taken place. And of course, that’s the next thing that we need to see — the data from the phase 3 clinical trials — before any consideration of authorization or approval takes place.
What happens after you see this data? Can you talk about the approval process and what the FDA will be looking for in the phase 3 trial results?
We have made every attempt to be transparent about this, and will continue to do so, so that all Americans understand what we’re doing from a regulatory point of view.
These phase 3 clinical trials are large trials with 30,000 or more participants, and they compare the active vaccine with a placebo to determine whether an infection occurs in a person participating in the trial — because what you’re looking for is a vaccine to prevent infection [with the coronavirus, SARS-CoV-2]. That’s the effectiveness side of things, and in our guidance for vaccine manufacturers [posted to the FDA’s website in June], we were very clear about the criteria: We said the floor for effectiveness would be 50 percent. [This means that the vaccine should be effective at preventing a coronavirus infection or decreasing its severity in at least 50 percent of vaccine recipients. For comparison, the influenza vaccine is between 40 percent and 60 percent effective.]
We also said that safety would be of the utmost importance to us, and on the safety side of things, we’re looking for side effects. Most recently in our guidance for emergency use authorization, we said that we need to see at least two months of follow-up for 50 percent of the participants after they get the final dose of the vaccine. Looking back at other vaccines, our scientists determined that two-month window was when the overwhelming majority of side effects would be seen.
What’s the difference between standard FDA approval and an emergency use authorization when it comes to a vaccine?
When the developers of the vaccine are in their clinical trials, they determine when their data are mature, and there’s an independent board, called a data safety monitoring board, that helps the manufacturers look at the data and determine whether they reached specified criteria. Then, they’ll apply to the FDA for either emergency use authorization (EUA) or a biological license application (BLA), which is the typical process for vaccine approval. Normally, it takes us months to go through an application in the BLA process. We could, and can, and will expedite that, but it’s a significant process.