Johnson & Johnson's COVID-19 Vaccine Candidate Paused After Study Participant Gets Sick

A late-stage study of Johnson and Johnson's COVID-19 vaccine candidate has been put on hold after a patient got sick.

Johnson and Johnson announced its trial is on hold due to an "unexplained illness" in a study participant.

In a statement, the company said an illness during a clinical trial is "not uncommon and is reasonably expected." The company said its physicians are working to determine what might have caused the illness. So far, Johnson and Johnson have not released any more details about the study participant or the illness.

Astrazeneca faced a similar issue earlier in the year but has since resumed the overseas portion of its trial.

Companies are required to investigate any serious or unexpected reaction that happens during drug testing.

Johnson and Johnson's vaccine candidate is a single-dose approach. Other vaccine candidates in the U.S. require two shots.

The company was hoping to enroll 60,000 volunteers to test this vaccine.