The Brazilian trial of the COVID-19 vaccine candidate by the University of Oxford and AstraZeneca would have been suspended if the volunteer who died had been part of the active arm, a source familiar with the situation said on Wednesday.
The comment would suggest the volunteer was part of the comparative control group, which is given a meningitis jab.
Participants and investigators are not told which group they are in.
(Reporting by Ludwig Burger in Frankfurt; Writing by Josephine Mason in London; editing by Jonathan Oatis)
