The U.S. government has purchased an additional 200 million doses of the Pfizer-BioNTech COVID-19 Vaccine, expected to be delivered from October 2021 through April 2022. This brings the total number of doses to be supplied to the U.S. government under its existing supply agreement to 500 million. In a separate announcement on June 10, 2021, Pfizer and BioNTech shared plans to provide the U.S. government with 500 million doses of the companies’ COVID-19 vaccine for donation to the world’s poorest...