Johnson & Johnson pauses its COVID-19 vaccine study after 'unexplained illness' in one of its 60,000 volunteers

Johnson&Johnson's COVID-19 vaccine study has been paused due to an unexplained illness in a study participant.

A document obtained by Stat News which was sent to outside researchers running the 60,000-patient clinical trial states that a 'pausing rule' has been met. 

It also stated that the online system used to enroll patients in the study has been closed and the data and safety monitoring board would be convened.

Johnson&Johnson confirmed the news to Stat News, saying it was due to 'an unexplained illness in a study participant.' 

In this undated photo provided by Johnson&Johnson, a woman receives an injection during phase 3 testing of a COVID-19 vaccine. The company announced on Monday it was pausing the trial after a patient experienced an 'unexplained illness'

The company declined to provide further details and cited patient privacy. 

In a statement, the company said: 'We must respect this participant’s privacy. We’re also learning more about this participant’s illness, and it’s important to have all the facts before we share additional information.' 

This is the second vaccine study to be paused. On September 8, a large study run by AstraZeneca and Oxford University was put on hold because a patient in the United Kingdom experience a suspected adverse reaction. 

It's believed the patient developed a spinal cord problem. Studies in the UK resumed about a week later, but it is still on hold in the United States. 

Johnson & Johnson started enrolling patients in its phase 3 study on September 23.  Researchers planned to enroll 60,000 participants in the U.S. and other countries.