• Dr. Anthony Fauci told CNBC on Tuesday he expects U.S. drug regulators to eventually grant full approval to Pfizer, Moderna and J&J's Covid vaccines.
• "The data are about as good as it gets," the White House chief medical advisor said.
• All three Covid vaccines are currently being distributed under emergency use authorizations.

White House chief medical advisor Dr. Anthony Fauci fully expects the coronavirus vaccines from Pfizer, Moderna and Johnson & Johnson will receive full approval from U.S. drug regulators, he told CNBC on Tuesday.

"The data are about as good as it gets. ... I would be astounded if these vaccines, namely the mRNA and the J&J, didn't get full approval," Fauci said on "Squawk Box."

All three Covid vaccines are currently authorized for distribution in the U.S. on an emergency basis, but none of them have received full approval from the Food and Drug Administration yet. Full approval would allow the drugmakers to market the shots directly to consumers and give employers more flexibility in mandating them.

Pfizer and Moderna's two-dose vaccines use mRNA technology, while J&J's single-shot vaccine uses an adenovirus.

More than 184 million people in the U.S., or 55.5% of the population, are at least partially inoculated against Covid, according to CDC data. Nearly 160 million people, or 48% of the population, are fully vaccinated.

The pace of vaccinations in the U.S. has slowed since the spring, even as concern about highly transmissible variants grows. Some people have argued that full approval of the vaccines would convince Americans on the fence to get the shots and give businesses more confidence to implement vaccine mandates.

"Even though we are still under an emergency use authorization, it's a bit different than other emergency use authorizations, which usually are granted with not nearly as much positive data as we have for these products," Fauci said. 

Pfizer and its German partner BioNTech were the first vaccine makers to file for full approval, in May, followed by Moderna on June 1. Both vaccines were cleared for limited use in December.

"The efficacy or the effectiveness in the real world is unquestioned, so we're going to get a full approval," he added. "The question is, it's just going to take a little bit more time." 

Fauci's appearance on CNBC comes one day after U.S. health officials, including Fauci, met with representatives from vaccine maker Pfizer to discuss the potential need for Covid booster shots.

Pfizer has said it sees signs that immunity from its two-dose vaccine declines over time and intends to pursue authorization for a booster shot. The company also is developing a booster meant to combat the highly contagious delta variant.

The FDA and Centers for Disease Control and Prevention have publicly pushed back on Pfizer's case for a third dose, releasing a joint statement last week that said people who are fully vaccinated do not need a supplemental shot right now.

Fauci described Monday's talk with Pfizer has mostly "a courtesy meeting." However, he emphasized that the discussion around booster shots "has absolutely nothing to do with the effectiveness of the vaccine."

"These vaccines are highly, highly effective both in the clinical trial and in the real-world effectiveness studies. Let me give you a cogent example: 99.5% of people who die of Covid are unvaccinated. Only 0.5% of those who die are vaccinated," said Fauci, the longtime head of the National Institute of Allergy and Infectious Diseases.

He said the real question is how long protection lasts and at what level of protection.

"Does it wane off and if so, how soon? And if you do do a boost, how high do you get the response up? Those were all discussed but … there was nothing that came even close to any decision," he said.