WASHINGTON, Oct. 23 (Xinhua) -- Multinational pharmaceutical company AstraZeneca and U.S. pharmaceutical company Johnson & Johnson announced Friday that they would resume their phase 3 clinical trials on COVID-19 vaccine candidates in the United States.
AstraZeneca's trial was put on hold just days after it began in early September, following an unexplained illness in one trial participant in Britain.
Johnson & Johnson's trial was paused on Oct. 12 due to an "unexplained illness" in a study participant.
AstraZeneca said Friday the U.S. Food and Drug Administration (FDA) has authorized the restart of the trial in the United States, following the resumption of trials in other countries in recent weeks.
The FDA has reviewed all safety data from trials globally and concluded it was safe to resume the trial, said the company in a statement.
As part of the standard review process for trial safety events, a voluntary pause on vaccination across all global trials was triggered on Sept. 6 to allow the examination of safety data by independent monitoring committees, according to the company.
The recommendations from these reviews have been supported by international regulators, who also confirmed that the trials were safe to resume, said the statement.
AstraZeneca said results from the late-stage trials are expected later this year.
Johnson & Johnson said Friday the independent Data Safety and Monitoring Board overseeing its phase 3 trial has recommended resuming trial recruitment.
Following consultation with the FDA, preparations to resume the trial in the United States, including submissions for approval by the Institutional Review Boards, are now underway, according to the company.
"After a thorough evaluation of a serious medical event experienced by one study participant, no clear cause has been identified," said the company in a statement.
Johnson & Johnson said there are many possible factors that could have caused the event. Based on the information gathered to date and the input of independent experts, the company has found no evidence that the vaccine candidate caused the event.
Unexpected adverse events, including illnesses, can occur in study participants during any clinical study, especially large studies. They can occur in both vaccine and placebo groups, according to Johnson & Johnson.
The company said it will share the full safety and efficacy results at the conclusion of the trial, which plans to enroll 60,000 adults 18 years old and older.
"We're very optimistic about both AstraZeneca and Johnson & Johnson resuming their trials just as quickly as possible," Paul Mango, deputy chief of staff for policy at the U.S. Department of Health and Human Services, said during a media call Friday. Enditem
