Healthcare US secures 300 million doses of potential AstraZeneca COVID-19 vaccine Updated : May 22, 2020 07:33 AM IST The US deal allows a late-stage, or Phase III, clinical trial of the vaccine with 30,000 people in the United States. AstraZeneca has already agreed to deliver 100 million doses to people in Britain, with 30 million as soon as September. Subscribe to Moneycontrol PRO at just Rs.33/- per month for the first year. Use code SUPERPRO. Limited period offer. Available on Web and Android.