The Biden administration plans to donate 500 million Pfizer (PFE.N) coronavirus vaccine doses to nearly 100 countries over the next two years. Read alsoAnother batch of Pfizer COVID-19 vaccine arrives in UkraineThe donations will go through the COVAX vaccine program that distributes COVID-19 shots to low- and middle-income countries. U.S. President Joe Biden will announce the deal on Thursday at the Group of Seven meeting of the world's wealthiest countries in Britain, one of the people said.