A Brazilian volunteer in a clinical trial of the COVID-19 vaccine developed by AstraZeneca and Oxford University has died.

But Brazilian health authority Anvisa said the trial would continue.

Oxford confirmed the plan to keep testing, saying in a statement that after careful assessment “there have been no concerns about safety of the clinical trial”.

AstraZeneca declined to comment immediately.

The Oxford-AstraZeneca vaccine is one of two COVID-19 vaccines the Australian Government has committed to purchasing and manufacturing locally, if they pass relevant safety checks.

The other vaccine is being developed by the University of Queensland, and is currently in a smaller early-stage phase 1 human trial.

A source familiar with the matter in Brazil told Reuters the trial of the AstraZeneca vaccine would have been suspended if the volunteer who died had received the COVID-19 vaccine, suggesting the person was part of the control group that was given a meningitis jab.

In phase 3 trials, generally half receive the vaccine and half receive a placebo — in this case meningitis.

So far, 8,000 of the planned 10,000 volunteers in the trial have been given the first dose in Brazil.(Reuters: Amanda Perobelli)

Trials of the Oxford-AstraZeneca COVID-19 vaccine are taking place in the UK, Brazil, South Africa and India in order to gauge a broader genetic cross-section and to assess any rare side effects.

The US trial of the vaccine has been on hold since September 6 after a participant in the UK trial fell ill sparking international concern over the safety of the jab.

However, international reports this week suggested the US Food and Drug Administration had completed its review and AstraZeneca would resume its trial as early as this week.

The Federal University of Sao Paulo, which is helping coordinate phase 3 clinical trials in Brazil, said an independent review committee had also recommended their trial continue.

The university earlier confirmed the volunteer was Brazilian but gave no further personal details.

“Everything is proceeding as expected, without any record of serious vaccine-related complications involving any of the participating volunteers,” the Brazilian university said in a statement.

So far, 8,000 of the planned 10,000 volunteers in the trial have been recruited and given the first dose in six cities in Brazil.

Many have already received the second shot.

Anvisa provided no further details, citing medical confidentiality of those involved in trials.