President Donald Trump on Tuesday announced the U.S. government will purchase 100 million doses of Moderna’s experimental coronavirus vaccine, which is currently in late-stage human trials. 

Moderna separately said the deal for its vaccine, mRNA-1273, is worth $1.525 billion and will give the federal government the option to purchase up to 400 million additional doses. The U.S. has already invested $955 million to develop Moderna’s vaccine, bringing its total investment up to $2.48 billion, the company said in a press release Tuesday. 

The U.S. government’s deal with Moderna follows similar agreements its made with pharmaceutical giants Pfizer and Johnson and Johnson for their potential Covid-19 vaccines. 

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