Johnson & Johnson Pauses COVID-19 Vaccine Trials

The company voluntarily paused its studies, including one in Phase 3, after an unexplained illness in a patient.

amanda heidt
| 3 min read
COVID-19, SARS-CoV-2, pandemic, coronavirus, clinical trials, safety, vaccine, Johnson & Johnson, Janssen

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Update (October 27): After the company did not find a cause for the participant’ s illness, Johnson & Johnson announced on October 23 that it is seeking to resume the clinical trial, according to a statement.

Johnson & Johnson’s Janssen subsidiary, one of several companies in Phase 3 testing of vaccines to prevent SARS-CoV-2 infection, has temporarily suspended enrollment and dosing in all of its clinical trials after a patient experienced an adverse reaction during its Phase 3 ENSEMBLE trial.

The incident was first reported on Monday (October 12) by STAT after reporters received a copy of a document sent to outside researchers running the study’s individual trials. The document states that a “pausing rule” had been met to justify the suspension and that the online system used to enroll patients was closed.

“We have temporarily paused further dosing in all our COVID-19 vaccine candidate clinical ...

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Meet the Author

  • amanda heidt

    Amanda Heidt

    Amanda was an associate editor at The Scientist, where she oversaw the Scientist to Watch, Foundations, and Short Lit columns. When not editing, she produced original reporting for the magazine and website. Amanda has a master's in marine science from Moss Landing Marine Laboratories and a master's in science communication from UC Santa Cruz.
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