Johnson & Johnson pauses COVID-19 vaccine trial due to 'unexplained illness'

Johnson & Johnson has temporarily paused its US COVID-19 vaccine clinical trial after a candidate succumbed to an "unexplained illness".

Releasing a statement this morning, the pharmaceutical giant said an independent committee overseeing the trial will now review and evaluate the individual's illness.

Some 60,000 participants are currently undertaking vaccine candidate clinical trial.

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If an unexpected serious adverse reaction is discovered as a result of the vaccine, the entire trial will be restarted.

Johnson & Johnson said that in such large cohorts of participants, these unexpected illnesses are expected.

"Adverse events – illnesses, accidents, etc. - even those that are serious, are an expected part of any clinical study, especially large studies," Johnson & Johnson said.

"Based on our strong commitment to safety, all clinical studies conducted by the Janssen Pharmaceutical Companies of Johnson & Johnson have prespecified guidelines.

"These ensure our studies may be paused if an unexpected serious adverse event (SAE) that might be related to a vaccine or study drug is reported, so there can be a careful review of all of the medical information before deciding whether to restart the study."

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The organisation said it could not share too much information about what the illness may be due to patient confidentiality.

"We must respect this participant's privacy," Johnson & Johnson said.

"We're also learning more about this participant's illness, and it's important to have all the facts before we share additional information."

The independent medical committee may find that the vaccine did not cause this unexpected illness, and the study may resume.

Johnson & Johnson has already agreed to supply up to 400 million doses of the vaccine to the European Union if it proves successful.

The pharmaceutical giant is the fourth company in the US to reach "Phase three" of clinical trials in the quest for a vaccine.

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