Drugmaker Pfizer topped sales and profits forecasts for the quarter and raised its outlook for the year on the strength of its vaccine business.

Company results released on Tuesday show the COVID-19 vaccine pulled in $3.5 billion in revenue in the first quarter alone, leading Pfizer to boost annual sales expectations for the vaccine by 70 percent. That puts the vaccine on track to make up more than one-third of Pfizer's total sales for the year. The two-shot vaccine quickly became Pfizer's best-selling product in the first quarter.

CEO Albert Bourla told investors in prepared comments that based on the evidence, there will be continued need for this vaccine, similar to what is seen yearly for the flu.

With that in mind, Pfizer is continuing to tweak production of the vaccine and is working on contracts with governments for 2022 and beyond.

It expects to hear from the FDA shortly on its application for expanded use of the vaccine to include youngsters 12 to 15 years old. That's as much as Pfizer would say on the matter.

The New York Times reported Monday that the U.S. Food and Drug Administration (FDA) is preparing to authorize the Pfizer and BioNTech vaccine for adolescents, citing federal officials familiar with the agency's plans.

But Pfizer did say it will seek approval later this year for emergency authorization for the vaccine to be used in children 2 to 5 and 5 to 11.

And that's not all. Pfizer is also working on a new formula that could potentially allow the vaccine to be stored at normal refrigeration temperatures, would make it easier to ship and store.

The success of the mRNA technology used in the COVID-19 vaccine has encouraged Pfizer to go ahead with plans to start clinical trials of a mRNA flu vaccine by the third quarter.

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