The Phase 3 study is expected to enroll up to 60,000 volunteers in more than 200 locations in the United States and around the world.
Johnson & Johnson announced that it had temporarily canceled its COVID-19 vaccine study because one of its participants fell ill.
“We have temporarily suspended further dosing in all of our clinical trials with COVID-19 vaccine candidates, including the Phase 3 ENSEMBLE study, due to an unexplained illness in a study participant,” the company was quoted as saying by the AFP news agency.
The hiatus means that the registration system for the clinical trial of 60,000 patients has been closed while the independent patient safety committee convenes.
J&J said Serious Adverse Events (SAEs) such as accidents or illness are “an expected part of any clinical trial, especially large trials”.
Dr. William Schaffner, professor of infectious diseases at Vanderbilt University School of Medicine, told Reuters that “everyone is on the alert” as to what happened to the AstraZeneca, adding that information gathering could take a week.
“It would have to be a serious adverse event. If it was something like prostate cancer, uncontrolled diabetes, or a heart attack, none of those reasons would stop it. This is likely a neurological event, ”he said.
According to company guidelines, they can pause a study to determine if the SAE is related to the drug in question and whether to continue the study.
60,000 volunteer participants
J & J’s Phase 3 trial began recruiting participants in late September, with the goal of recruiting up to 60,000 volunteers in more than 200 locations in the US and around the world, the company and the US National Institutes for Health (NIH), which are offering this to raise funding, said.
The other countries where the trials took place were Argentina, Brazil, Chile, Colombia, Mexico, Peru and South Africa.
With this step, J & J became the 10th manufacturer worldwide to conduct a phase 3 study against COVID-19.
The US has provided J & J with around USD 1.45 billion as part of Operation Warp Speed.
The vaccine is based on a single dose of a cold-causing adenovirus that is modified so that it can no longer replicate, combined with part of the new coronavirus, the spike protein, which is used to penetrate human cells.
J&J used the same technology for its Ebola vaccine, which received marketing approval from the European Commission in July.
Preclinical tests on rhesus monkeys published in the journal Nature showed that they offer complete or near complete protection against viral infections in the lungs and nose.
As with several other ongoing Phase 3 studies, the main objective is to test whether the vaccine can prevent symptomatic COVID-19.
In September, trials of the coronavirus vaccine developed by AstraZeneca and Oxford University were halted after a British volunteer developed an unexplained disease.
The vaccine is one of the most advanced Western projects and has already been tested on tens of thousands of volunteers around the world.
Trials resumed earlier this month in Japan, with the exception of the US, where AstraZeneca is working with regulators.