Johnson & Johnson has paused its Covid-19 vaccine trial due to an “unexplained illness” in a participant, the company confirmed. The pharmaceutical giant was unclear if the patient was administered a placebo or the experimental vaccine, and it’s not remarkable for studies as large as the one Johnson & Johnson are conducting – involving 60,000 patients – to be temporarily paused.
A document sent to outside researchers running the 60,000-patient clinical trial states that a “pausing rule” has been met, that the online system used to enroll patients in the study has been closed, and that the data and safety monitoring board — an independent committee that watches over the safety of patients in the clinical trial — would be convened. The document was obtained by STAT.
Contacted by STAT, J&J confirmed the study pause, saying it was due to “an unexplained illness in a study participant.” The company declined to provide further details.
Johnson & Johnson did not reveal the nature of the illness that brought its trial to a standstill, noting in a statement: “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,” the statement continued. The illness is being investigated by the company as well as an independent board.
Though clinical trial pauses are not uncommon — and in some cases last only a few days — they are generating outsized attention in the race to test vaccines against SARS-CoV-2, the virus that causes Covid-19.
On Sept. 8, a large study of another Covid-19 vaccine being developed by AstraZeneca and Oxford University was put on hold because of a suspected adverse reaction in a patient in the United Kingdom. It’s believed that the patient had transverse myelitis, a spinal cord problem. Studies of the vaccine resumed roughly a week after it was paused in the United Kingdom, and have since been restarted in other countries as well. It remains on hold, however, in the United States.
Johnson & Johnson began enrolling volunteers in its Phase 3 study on Sept. 23. Researchers planned to enroll 60,000 participants in the United States and other countries.