Washington (AFP)

Pharmaceutical group Johnson & Johnson announced on Monday the suspension of its clinical trial of a vaccine against Covid-19, one of the participants having fallen ill.

"We have temporarily suspended additional dosing in all of our clinical trials of an investigational Covid-19 vaccine, including the entire Phase 3 trial, due to unexplained illness in one participant," said the group said in a statement.

This suspension results in the closure of the online registration system to recruit participants for phase 3 of the trial, while the independent committee for patient safety has been seized.

Serious adverse events are "an expected component of any clinical study, especially large studies," Johnson & Johnson said.

Company protocols provide for the suspension of a study to determine if the serious adverse event is related to the drug being evaluated and if it is possible to resume the trial.

The recruitment of volunteers for phase 3 of the Johnson & Johnson clinical trials began at the end of September, in order to engage 60,000 participants at more than 200 sites in the United States, and in other countries, announced the group and the US National Institute of Health (NIH).

Trials were also taking place in Argentina, Brazil, Chile, Colombia, Mexico, Peru and South Africa.

Johnson & Johnson had thus become the 10th group in the world to conduct phase 3 trials against Covid-19, and the 4th in the United States.

The United States has provided some $ 1.45 billion in funding to Johnson & Johnson as part of the White House's operation to produce vaccines, Operation Warp Speed.

Its vaccine candidate is based on a single dose of an adenovirus, which causes the common cold, modified so that it cannot replicate and combined with a part of the Sars-CoV-2 coronavirus called the spike protein (or "spike" ) that it uses to enter human cells.

The Johnson & Johnson laboratory had used the same technique for its vaccine against Ebola hemorrhagic fever, whose marketing was approved by the European Commission in July.

Last September, clinical trials of the candidate vaccine against Covid-19 developed by AstraZeneca and the University of Oxford, considered one of the most promising, were also interrupted after a British participant developed an unexplained pathology .

These trials resumed in Japan in early October but not in the United States where the pharmaceutical giant says it is working with the drug authority.

© 2020 AFP