Drugmaker AstraZeneca struck a deal Saturday to supply up to 400 million doses of an experimental COVID-19 vaccine to European Union countries, the latest in a series of agreements as scientists, governments...

Drug maker AstraZeneca said Thursday it had secured its first agreements for 400 million doses of a COVID-19 vaccine it is testing, bolstered by an investment from the U.S. vaccine agency. The Anglo-Swedish...