The Trump administration has reached an agreement with Pfizer and BioNTech to purchase 100 million additional doses of their coronavirus vaccine, which will be fully delivered no later July 31, 2021, the Department of Health and Human Services announced Wednesday.

Why it matters: The deal will allow millions more Americans to be vaccinated at zero cost by next fall. Under the terms of the agreement, 70 million of the 100 million doses purchased will be delivered by June 30, 2021.

The big picture: 200 million Pfizer doses — enough to vaccinate 100 million Americans — have now been secured, with the deal containing options for the U.S. government to purchase an additional 400 million.

  • Moderna, the only other company whose vaccine has received emergency authorization from the FDA, has agreed to supply the U.S. government with 200 million doses by June 2021.
  • That’s the date at which HHS Secretary Alex Azar has said every American who wants a vaccine should be able to receive one.

The state of play: In addition to the 400 million Pfizer and Moderna doses purchased by the U.S. government, Operation Warp Speed has also secured the following amounts for vaccines that are not yet authorized by the FDA …

  • Johnson & Johnson: 100 million doses
  • AstraZeneca: 100 million doses
  • Novavax: 100 million doses
  • Sanofi/GlaxoSmithKline: 100 million doses

This story is developing. Please check back for updates.