The US could have 50 million vaccine doses before it’s ready to use them

The US Food and Drug Administration (FDA) may not authorize a Covid-19 vaccine until January 2021 at the earliest, according to Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases—but that isn’t stopping drug manufactures from cranking them out by the millions ahead of time.

Between Moderna and Pfizer, makers of the two vaccines emphasized in federal distribution preparedness plans, the US should have access to at least 50 million vaccine doses by the end of 2020. Assuming each person receives two doses for maximum immunity, that’s enough to vaccinate 25 million Americans—less than 10% of the US population. But until the FDA gives the green light, those doses will have to stay in cold storage.

In an earnings call on Oct. 23, Pfizer CEO Albert Bourla stated that the company had already made “hundreds of thousands” of doses of its Covid-19 vaccine candidate; he expects to have 30 million to 40 million doses ready to deliver to the US by the end of the year, with plans to reach 100 million by March 2021. And today, Oct. 29, Tal Zaks, the chief medical officer of Moderna, said that he expects to be able to provide 20 million doses of its candidate to the US by the end of the year.

Read the rest of this story on qz.com. Become a member to get unlimited access to Quartz’s journalism.