Two main trucks left the Pfizer facility on Sunday morning, the company said.
A pandemic of the novel coronavirus has now infected more than 71.5 million people and killed over 1.6 million worldwide, according to real-time data compiled by the Center for Systems Science and Engineering at Johns Hopkins University.
With Sunday's vaccine shipment now in transit, Pfizer has began preparations to ship out an additional 400 boxes of the vaccine on Monday.
There are 975 vials per box -- each vial provides five doses of the COVID-19 vaccine, the company said.
There are 195 vials per tray and 60,000 vials per freezer.
The first vaccines in the U.S. have now left the Pfizer facility and are on their way to all 50 states.
Two main trucks left on Sunday morning -- an additional truck will come in later to pick up a few boxes and take them to the U.S. territories.
On Monday Pfizer has an order for another 400 boxes of the vaccine as well as an order for a slightly less amount of boxes on Tuesday, the company said.
The first shipments are expected to arrive at 145 sites on Monday, 425 sites on Tuesday and another 66 sites on Wednesday, Gen. Gus Perna of the Trump administration's Operation Warp Speed vaccine program said.
At those sites, the vaccines will be paired with ancillary kits to assist with the vaccinations. The kits contain needles, syringes, alcohol swabs, diluent, safety gear and vaccine reminder cards.
-ABC News' Joshua Hoyos and Luis Martinez
FedEx has begun its shipment process of the Pfizer vaccine in the U.S. on Sunday morning, the company posted on Twitter.
Starting Wednesday, Dec. 16 through Jan. 10, all non-essential stores and schools will be closed in Germany and social meetings will be limited to five people from two households, with an exception made for the Christmas period from Dec. 24 to Dec. 26 when four more people beyond a household will be allowed.
No exceptions will be made for New Year's Eve.
COVID-19 transmissions remain high in the country despite softer restrictions in place. As of Dec. 13, the Robert Koch Institute reported a total of 20,2000 new cases and 321 deaths, bringing the totals to 1,320,716 and 21,787, respectively.
Germany had initially planned for a "semi-lockdown," allowing for a holiday exemption from Dec. 23 to Jan 1 where up to 10 people from two households could meet but those plans were scrapped in favor of these new rules.
ABC News' Christine Theodorou contributed to this report.
