Pfizer brought in $3.5 billion from COVID-19 vaccine sales in the first 3 months of 2021

• Pfizer on Tuesday reported its financials for the first three months of 2021.
• The pharmaceutical company brought over $3 billion from sales of its coronavirus vaccine.
• It expects to generate $26 billion in revenue from the shot through the rest of the year.

Pfizer has sold hundreds of millions of doses of its COVID-19 vaccine to the United States, and even more around the globe, resulting in more than $3.5 billion in revenue during the first three months of 2021, the company said Tuesday.

Sales of the two-shot vaccine made up nearly a quarter of the pharmaceutical giant's first-quarter revenues of $14.6 billion, easily its biggest income driver, though the company has been tight-lipped about how those sales translate to profits.

Shares of Pfizer were little changed in early trading Tuesday following the results.

Pfizer now expects to deliver a total of 1.6 billion vaccine doses in 2021, generating $26 billion in revenue. That's up significantly from previous forecasts of $15 billion. The company now says 2021 revenues will fall between $70.5 billion and $72.5 billion, a more than $10 billion increase over prior guidance.

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The vaccine tailwinds from the shot will likely carry on into 2022. In April, Pfizer CEO Albert Bourla said people may need a booster shot 12 months after their first dose. And the company said Tuesday it expects to have the capacity to produce 3 billion doses in 2022.

"Based on what we've seen, we believe that a durable demand for our COVID-19 vaccine - similar to that of the flu vaccines - is a likely outcome," Bourla said in a prepared commentary ahead of a call with investors.

Pfizer did not specify how much it has profited from its vaccine, largely the winner of the world's race to inoculate against the virus, but said it continues to expect margins in the high 20 percents. That would indicate a profit of roughly $900 million from January through March, and up to $6.5 billion for the year.

BioNTech, the German biotechnology firm that co-developed Pfizer's shot, also stands to bring in billions from the vaccine, as the two companies split vaccine sales.

Other drug companies like Johnson & Johnson and AstraZeneca have pledged not to profit on their vaccines until the pandemic is under control. Pfizer has said it will not profit from the sale of its vaccine to poorer countries.