Johnson & Johnson pauses COVID-19 vaccine amid unexplained illness in trial participant

Johnson & Johnson announced Monday that it had become the second company to halt its trials on a COVID-19 vaccine due to an “unexplained illness” affecting a trial participant.

No information about the illness was immediately available other than that it was being evaluated, according to Bloomberg Quint.

“We are committed to providing transparent updates throughout the clinical development process of our vaccine candidate,” Johnson & Johnson said in its statement. “Adverse events – illnesses, accidents, etc. – even those that are serious, are an expected part of any clinical study, especially large studies.”

The company’s announcement follows a similar statement from AstraZeneca, which is operating a COVID-19 trial in several countries, last month. The company cautioned at the time that it was possible the illness was unrelated to the vaccine trials.

“As part of the ongoing randomised, controlled global trials of the Oxford coronavirus vaccine, our standard review process triggered a pause to vaccination to allow review of safety data,” AstraZeneca said in September. “This is a routine action which has to happen whenever there is a potentially unexplained illness in one of the trials, while it is investigated, ensuring we maintain the integrity of the trials.”

“In large trials illnesses will happen by chance but must be independently reviewed to check this carefully,” the company added at the time. “We are working to expedite the review of the single event to minimise any potential impact on the trial timeline.”

Numerous companies have received federal funding for their vaccine efforts as part of Operation Warp Speed, the White House’s efforts aimed at securing a U.S.-made COVID-19 vaccine by the end of 2020.