Pfizer Inc. and its partner BioNTech SE have asked U.S. regulators for full approval of their COVID-19 vaccine, a milestone in their effort to make the shot a sustainable revenue source that goes well beyond its current standing as an emergency product.

On Friday, the companies became the first COVID-19 vaccine makers to submit a biologics license application to the U.S. Food and Drug Administration. Their vaccine is one of three – along with shots made by Moderna Inc. and Johnson & Johnson – that hold an emergency use authorization in the U.S., a designation that can be revoked at any time and lasts only as long as the state of emergency itself.

In submitting a BLA, Pfizer and BioNTech will subject their vaccine to greater scrutiny by the FDA, potentially helping to offset worries by some Americans that the shot may have been produced too quickly to guarantee its long-term safety. Data to support the application will be submitted to the regulator on a rolling basis in coming weeks.

If cleared, the companies would be able to begin marketing the product to the general public. The full approval would also allow more employers to begin mandating vaccination. Moderna says it plans to initiate a rolling submission for a BLA for its COVID-19 vaccine this month.

The submission follows the “tremendous progress” they have made in delivering vaccines to millions of Americans and is the next step in a “rigorous FDA review process,” the companies said a statement.

As part of the application, they have submitted nonclinical and clinical data, including the most recent analysis from the Phase 3 clinical trial, where the vaccine’s efficacy and safety profile were observed for as long as six months after the second dose. The duo will also submit required manufacturing and facility data in the coming weeks.

The companies will first seek approval for the vaccine’s use in individuals 16 years of age and older, but also intend to submit a supplemental biologics license application for those aged 12 to 15 once the required data is available.

Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said in April that the review process typically takes six months, but that U.S. regulators would attempt to move faster than that.

The Pfizer-BioNTech vaccine was designed using messenger RNA technology. It works by instructing cells in the body to generate the spike protein that initiates the coronavirus infection, spurring an immune response.

On April 1, Pfizer and BioNtech reported follow-up data from a final-stage trial of 46,307 people showing the vaccine was 91.3% effective in preventing symptomatic cases starting one week after the second dose for as long as six months. In the U.S. alone, the efficacy rate was 92.6%.

Countries around the world are now reporting real-world data showcasing that the vaccine might handle variants. In Qatar, for example, the two-shot regimen proved to be nearly 90% effective at preventing infection with B.1.1.7, and about 75% against the B.1.351 strain, according to analysis run on a national database of more than 200,000 people.

BioNTech Chief Executive Officer Ugur Sahin has said those who have been fully vaccinated will still likely need a booster shot of the same formulation in six to nine months. The company has begun evaluating an updated formulation specific to the South African variant.

With full approval in hand, Pfizer and BioNTech would finally be able to advertise the product under its branded name, Comirnaty, and distribute the two-shot regimen directly to a wider marketplace. In the U.S., only federal entities have been able to purchase supply.

“Right now we can only commercialize the vaccine in the U.S. through the government,” Pfizer CEO Albert Bourla said in an interview on Tuesday. “That will open our ability to commercialize the vaccine through all the channels that exist.”

Bourla said that being granted such a license wouldn’t immediately change the way the Pfizer-BioNTech vaccine reaches people around the world, given governments have secured significant supply.

The license would also shift the legal status of the shot, according to the FDA’s Marks, clearing the way for employers and other organizations to mandate vaccination.

“Once the vaccine is approved there is a different legal status in terms of what employers can potentially require,” Marks said on April 14, during a webinar sponsored by the American Medical Association. He added that such a mandate may particularly impact the U.S. military.

Pfizer and BioNTech aim to make 3 billion doses in 2021, much of which has already been purchased by governments around the world. Through year-end, Pfizer expects the vaccine to yield $26 billion in sales. Half of the profits will go to BioNTech.

Looking forward, however, Pfizer executives envision commercializing the COVID vaccine much like a seasonal flu shot. The New York-based drugmaker and its German partner said they can make more than 3 billion doses in 2022, and are already clinching multi-year supply agreements with governments that would allow them to continue to boost protection as immunity wanes and new virus mutations emerge.

Once the pandemic has subsided, Pfizer plans to raise the price of the shot, Chief Financial Officer Frank D’Amelio told investors in February. The U.S. government paid $19.50 per dose, or $39 for the full regimen. “Obviously, that’s not a normal price like we’d typically get for vaccine,” he said. “We’re going to get more on price.”

Bourla, speaking on the same call, said he expects an “open market” to boost sales.

“If this was an open market, which means that the physicians and citizens, they have the ability to choose which vaccine they will receive, I would feel very comfortable that we will have the lion market share,” he said in February.