The man in charge of evaluating coronavirus vaccines for the FDA lays out why it will take weeks to vet a COVID-19 shot

• As coronavirus vaccines inch closer to reality, the man in charge of reviewing the approval applications wants Americans to trust the process.
• That means we're not going to get surprise Food and Drug Administration approvals in the coming days, despite two COVID-19 vaccine frontrunners announcing success over the past week.
• The review process will be measured in weeks, Dr. Peter Marks, director of the FDA's center for biological products, told Business Insider on Friday.
• "Everything that we are trying to do here, this is all about ensuring the public re-develops the kind of trust they once had in vaccines," Marks said.

The man in charge of reviewing the applications for coronavirus vaccine candidates has a clear message for the American public: Trust the process.

It'll play out before your eyes over the next few weeks.

"Look at the process that we're following," Dr. Peter Marks, the leader of the Food and Drug Administration's biologics center, said in a Friday phone interview with Business insider. "We're going to have a very open process."

While the coronavirus pandemic rages across the country as it never has before, the hopes for a vaccine that can pull society out of this crisis have strengthened in recent days.

The pharmaceutical giant Pfizer and its German partner BioNTech said on November 9 its vaccine candidate was more than 90% effective at preventing COVID-19 in an interim analysis of a massive clinical study. The upstart Massachusetts biotech Moderna said Monday its two-dose regimen was 94.5% effective, according to preliminary results from a late-stage trial.

But the intense effort to develop a COVID-19 shot in record time has left many Americans feeling uneasy about the quick timeline. Recent surveys have shown an increasing number of Americans are hesitant to get a COVID-19 shot.

It's ultimately up to the FDA to decide whether it will authorize the experimental coronavirus vaccines, and the vetting process is expected to take weeks, Marks said. By taking time rather than rushing to an authorization, the hope is to build up more conviction in the final products.

"What we need here is confidence," Marks said. "Everything that we are trying to do here, this is all about ensuring the public re-develops the kind of trust they once had in vaccines."

Read more: 'Crazy hours, short nights': The inside story of how a buzzy biotech upstart developed a potential coronavirus vaccine in record time

'We have to take the amount of time that we need to take'

Despite the encouraging reports, the data still has to be scrutinized before any shot is rolled out to the public.

That's where Marks comes in as the director of the FDA's Center for Biologics Evaluation and Research. He'll be overseeing the coronavirus vaccine review process, and said he is intent on running a transparent process to build trust.

Even amid a surging pandemic with rising levels of infections, hospitalizations, and deaths in the US, Marks is sticking to the steps.

That is, don't hold your breath for an overnight FDA approval or emergency OK for Pfizer or Moderna.

Marks said said it would take "weeks" to review any vaccine application.

"We have to take the amount of time that we need to take," Marks said. "The caveat here with saying this word 'weeks' is there are situations whereby the quality of what comes in and the complexity of what comes in will determine how long it will take to do a review that we can feel very confident in."

If that vetting process isn't followed, Marks said he would resign from the agency.

"You will see me leave if somebody said 'we're not going to look at the data, just get the thing approved,'" he said.

Read more: How the pharma giant Pfizer teamed up with a little-known biotech to develop an effective coronavirus vaccine in record time

A long regulatory road ahead, with the goal of building public trust

Before a vaccine is approved, companies have to submit it to the FDA for review.

Neither Moderna or Pfizer have even submitted an application for emergency use authorization (EUA) to regulators yet. Both companies are still collecting the required safety information from trial participants and anticipate submitting to the FDA in the next couple weeks.

From there, the FDA has its own process to follow. Career scientists will pore over the data and ultimately make a recommendation to authorize a vaccine. The agency will also consult a group of independent experts to share their advice.

This expert panel, known as an advisory committee, will take some time to set up, Marks said. The FDA needs time to prepare briefing documents that summarize the data and set the agenda for the panel's meeting.

"I can't give you an exact timing, but it's going to be a matter of weeks between when we get a submission and having an AdComm," Marks said.

This isn't bureaucratic red tape — the advisory committee meeting is one of the public's best views into the review process. The group will pick apart the data in a publicly broadcasted meeting and ultimately vote on whether or not to authorize the shot.

"They'll hear some of the warts, as well as some of the benefits," Marks said on what the public could expect. "I think that is actually what truth looks like. I think actually people are better than we think at seeing what the truth really is and recognizing that."

The FDA's own review will then carry on, taking into consideration the expert panel's perspective. The agency isn't required to follow the expert panels' recommendations, but often does so.

Now that the vaccine frontrunners appear to be highly effective, all eyes will soon turn to the FDA for the next steps. Marks said the agency is ready for the challenge that lies ahead.

"We feel motivated ourselves to move as quickly as we possibly can," Marks said. "This is not coming from anyone outside of the agency or inside of the agency except ourselves, because we understand how important this is."