Moderna is holding off on filing for Emergency Use Authorization (EUA) for its COVID-19 vaccine in children ages six to 11. The company made this decision after the U.S. Food and Drug Administration (FDA) extended its review of Moderna's EUA filing in adolescents ages 12 to 17. 

This leaves Pfizer (PFE -1.31%) and its partner BioNTech (BNTX -0.82%) clearly in the driver's seat in the COVID-19 vaccine market for children. The two companies won U.S. EUA for their vaccine in kids ages five to 11 last week.

But how much extra money Pfizer will make from its COVID-19 vaccine for younger kids this year? The answer might surprise you.

A masked child receiving a shot in the arm.

Image source: Getty Images.

Nothing extra

No one knows at this point how many parents will choose to vaccinate their younger children. Over 6.3 million kids have been diagnosed with COVID-19 in the U.S. so far. There have been only 455 deaths for children between 5 and 18. However, tens of thousands of kids have been hospitalized.

But regardless of how many doses of the Pfizer-BioNTech COVID-19 vaccine are given to younger kids, we can estimate quite accurately how much extra revenue that Pfizer will receive this year as a result. The number totals... $0.

The operative word is "extra." Pfizer won't make any extra money this year from the administration of its vaccine in younger kids for a simple reason: It won't sell any additional doses. Don't look for Pfizer's temporary monopoly in the younger market to have much impact on the pharma stock

So far, the U.S. government has ordered 500 million doses of the Pfizer-BioNTech COVID-19 vaccine. More than 247 million doses have already been administered in the U.S. That leaves well over 252 million doses.

There are fewer than 30 million kids in the U.S. between the ages of 5 and 11. Even if all of them are vaccinated (an unlikely scenario), it will require less than 60 million doses. The U.S. would still have plenty of doses of the Pfizer-BioNTech vaccine remaining for authorized groups to receive boosters.

Long-term opportunity

It is possible, though, that Pfizer could generate significant sales of its COVID-19 vaccine with younger kids over the longer term. Although we can't know for sure how much the company could make, we can at least come up with a reasonable estimate.

Let's assume that COVID-19 is similar to the flu going forward. Under this scenario, annual COVID-19 vaccines will be needed. Let's also suppose that vaccination rates in children are similar for COVID-19 as they are for the flu -- nearly 64% in 2020. Using roughly 30 million children between the ages of five and 11 (which is a little on the high side), more than 19 kids would receive annual COVID-19 vaccines each year.

At Pfizer's current price per dose of $19.50, this represents a market of more than $370 million. However, Pfizer has indicated that it will probably charge more once the pandemic is over. One analyst thinks the company could up its price by three to four times higher, based on the pricing of Pfizer's other vaccines.

If we go with a 3X price tag, the COVID-19 vaccine market for younger children could top $1.1 billion. Pfizer probably won't have that market all to itself, though. But if the company can command a similar market share in the future to what it has now overall, Pfizer could realistically make in the ballpark of $650 million per year. Of course, it would then have to split profits with BioNTech.

Competing with itself?

There's one other wild card, though, that shouldn't be ignored. Pfizer hopes to file for EUA of its COVID-19 pill by the end of this year. Assuming it wins EUA, the company will likely compete against  Merck, which could soon win EUA for a COVID-19 pill developed with its partner Ridgeback Biotherapeutics.

It's possible that Pfizer will also compete against itself. Some could choose to forego vaccination if a safe and effective COVID-19 pill is available. At least initially, COVID-19 pills would probably only be used in adults. Over the longer term, however, the use could expand to younger age groups.

All of this underscores how many moving parts there are in trying to determine how the COVID-19 vaccine market will evolve.