Johnson & Johnson Halt All Covid-19 Vaccine Trials Over ‘Unexplained Illness’

Published 3 years ago
A doctor’s hand with a syringe of covid-19 coronavirus vaccine.

Johnson & Johnson has become the latest Covid-19 vaccine frontrunner to put its trials on hold due to safety concerns after a participant fell ill, the company said in a statement Monday, following a similar move by AstraZeneca in September.


The U.S. company said it was not immediately clear what had caused the adverse reaction in the participant, whether it was linked to the vaccine or even if the participant had received the vaccine, as opposed to a placebo.

An independent data safety monitoring board, in addition to the company’s own physicians, is monitoring the participant’s illness, the company said, adding that it is important to “have all the facts” and respect the participant’s privacy before sharing further information.  


Though serious adverse events are not uncommon in clinical trials, the pause to Johnson & Johnson’s research might add to existing concerns over the safety of Covid-19 vaccines being at a much faster pace than is usual.

“Adverse events – illnesses, accidents, etc. – even those that are serious, are an expected part of any clinical study, especially large studies,” the company said in a statement.


Johnson & Johnson is a frontrunner in the race to develop a Covid-19 vaccine, launching a large, 60,000-person phase 3 trial for its single dose vaccine last month. Without further information from the company, it’s impossible to tell which study this participant might be linked to or whether they had even received the vaccine.Adverse events are not uncommon in clinical trials— another fairly advanced Covid-19 vaccine trial by AstraZeneca was put on hold in early September. But amid the rush to develop a vaccine, the World Health Organization has warned against countries taking a nationalistic approach, and instead is pushing for a “collective” effort. Meanwhile, as President Donald Trump pushes for a vaccine before the November 3 election,there is already evidence that his approach has eroded public trust in its safety, even if FDA-approved. 


Hassan Vally, an associate professor in epidemiology at La Trobe University in Melbourne, told Bloomberg that these kinds of pauses are going to be more commonplace as more are vaccinated. “We’re going to have to get used to hearing these sorts of reports of pauses,” he said. “As you vaccinate more people in these trials the chances are that there will be some illnesses in participants. The only difference here is that in the world that we live in right now, the progress of these trials are in the public eye, and so we are riding every bump.”



$1 billion. That’s how much Johnson & Johnson received from the federal government as a part of Operation Warp Speed.


Further updates from Johnson & Johnson as they evaluate the trial and its participants to determine the cause of the adverse event.

By Robert Hart, Forbes Staff