Second COVID-19 Vaccine Trial Halted Over Unexplained Illness

Oct 13, 2020

A late-stage study of Johnson & Johnson’s COVID-19 vaccine candidate has been paused while the company investigates whether a study participant’s “unexplained illness” is related to the shot.

The company said in a statement Monday evening that illnesses, accidents and other so-called adverse events are an expected part of large clinical studies.

Its physicians and a safety monitoring panel will try to determine what might have caused the illness.

The pause is at least the second such hold to occur among several vaccines that have reached large-scale final tests in the U.S. Final-stage testing of a vaccine made by AstraZeneca and Oxford University remains on hold in the U.S., though it has restarted elsewhere.