Johnson & Johnson’s COVID-19 vaccine study has been paused due to an unexplained illness in a study participant, the company announced on Monday.
“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,” J&J said in a statement on its website.
“Following our guidelines, the participant’s illness is being reviewed and evaluated by the ENSEMBLE independent Data Safety Monitoring Board (DSMB) as well as our internal clinical and safety physicians.”
The company added that it is learning more about the participant’s illness, and that it is “important to have all the facts” before it shares additional information.
Stat News reported on Monday that a document sent to outside researchers running the 60,000-patient clinical trial had stated that a “pausing rule” has been met, the online system used to enrol patients in the study has been closed, and the data and safety monitoring board would be convened.
J&J said that its pre-specified guidelines for clinical studies ensure that if an unexpected serious adverse event occurs, “there can be a careful review of all of the medical information before deciding whether to restart the study.”
In its announcement, the company made a distinction between the use of the terms “study pause” and “regulatory hold,” with the former being initiated by the study sponsor and is a “standard component of a clinical trial protocol,” and the latter being a requirement by a regulatory health body, such as the U.S. Food and Drug Administration (FDA).
J&J said that it typically does not communicate study pauses publicly, but proactively discloses any regulatory hold of a “pivotal clinical trial.”
The J&J COVID-19 vaccine is being developed by the company’s Janssen Pharmaceutical Companies. The company announced the start of its Phase 3 trial in late September, becoming the fourth manufacturer to reach this phase in clinical trials amid the CCP (Chinese Communist Party) virus pandemic.
The phase three trial marks the final step before drug manufacturers can seek emergency use authorization to widely distribute their vaccines. There is no authorized vaccine for COVID-19 yet.