J&J puts COVID-19 vaccine trial on pause following ‘unexplained illness’

Johnson & Johnson's current log on display.

Johnson & Johnson announced late Monday that it is “pausing” its clinical trials for a COVID-19 vaccine due to an unexplained illness in a study participant.

The New Brunswick-based company noted that the event is a study pause — part of the standard protocol for testing — as opposed to a “regulatory hold,” which is a requirement by a health agency, such as the Food and Drug Administration.

“We have temporarily paused further dosing in all our COVID-19 vaccine candidate clinical trials, including the Phase 3 ENSEMBLE trial, due to an unexplained illness in a study participant,” the company said in a statement.

The company also said safety of the participants was the top concern.

“At Johnson & Johnson, there is no greater priority than the safety and well-being of the people we serve every day around the world,” the company said. “We are committed to providing transparent updates throughout the clinical development process of our vaccine candidate, in compliance with regulatory standards and our own high ethical and scientific principles.”

The company said the participant’s illness is being reviewed and evaluated by the ENSEMBLE independent Data Safety Monitoring Board as well as J&J’s internal clinical and safety physicians. And it noted that adverse events — even those that are serious — are an expected part of any clinical study, especially large studies.

“Based on our strong commitment to safety, all clinical studies conducted by the Janssen Pharmaceutical Cos. of Johnson & Johnson have prespecified guidelines,” the company said. “These ensure our studies may be paused if an unexpected serious adverse event 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.”

The company did not release any information about the individual, citing privacy concerns. It also said it is learning more about this participant’s illness, and that, “It’s important to have all the facts before we share additional information.”