Coinspeaker AZN Stock Slightly Down, AstraZeneca Resumes Vaccine Trials in Japan, in Talks with U.S. AuthoritiesAstraZeneca’s clinical trials for the vaccine were halted in July after one of the participants complained of neurological disorder.AZN Stock Slightly Down, AstraZeneca Resumes Vaccine Trials in Japan, in Talks with U.S. Authorities