AstraZeneca had been counting on findings from a predominantly U.S. study of 32,000 people to help rebuild confidence in a vaccine that, despite being widely used in Britain, Europe and other countries, has had a troubled rollout. Previous studies have turned up inconsistent data about its effectiveness, and then last week a scare about blood clots had some countries temporarily pausing inoculations. Most have since restarted after the European Medicines Agency said the vaccine doesn’t increase the overall incidence of blood clots. But it could not rule out a connection to some rare blood clots and issued new advice for monitoring those who get vaccinated.
AstraZeneca updates disputed US study, says COVID-19 vaccine 76% effective
