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The Johnson & Johnson Covid-19 vaccine study was suspended due to an unexplained illness in a study participant.
A document sent to outside researchers conducting the clinical trial of 60,000 patients states that a "pause rule" has been met, that the online patient enrollment system for the study has been closed, and that the data and safety oversight panel has been closed – an independent body – a committee established to monitor patient safety in the clinical trial – would be convened. The document was obtained from STAT.
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Contacted by STAT, J&J confirmed the study break, saying it was due to "an unexplained illness in one study participant". The company declined to provide further details.
"We must respect this participant's privacy. We also learn more about this participant's illness and it is important to have all the facts before we provide any additional information," the company said in a statement.
J&J emphasized that so-called adverse events – illness, accidents, and other poor medical outcomes – are an expected part of a clinical trial, and also emphasized the difference between a study break and a clinical standstill, which is a formal regulatory measure that can takes a lot longer. The vaccine study is currently not in a clinical phase. J&J said it usually reports clinical issues to the public, but does not typically inform the public about study breaks.
The DSMB [Data and Safety Monitoring Board] met late Monday to look into the case. J&J said that in such cases, "it is not always immediately apparent" whether the participant who experienced the adverse event received study treatment or a placebo.
Although breaks are not uncommon in clinical trials – and in some cases only a few days – they are attracting undue attention in the race to test vaccines against SARS-CoV-2, the virus that causes Covid-19.
Given the size of the Johnson & Johnson study, it's not surprising that study breaks can occur and another when that is resolved, according to a source familiar with the study.
"If we do a study on 60,000 people, it's a small village," the source said. "A lot of medical incidents happen in a small village."
On September 8, a large study of another Covid-19 vaccine being developed by AstraZeneca and Oxford University was suspended on suspicion of side effects in a patient in the UK. The patient is believed to have had transverse myelitis, a spinal cord problem. Studies on the vaccine resumed in the UK about a week after his break and have since resumed in other countries. However, it remains on hold in the United States.
Johnson and Johnson began enrolling volunteers in their Phase 3 study on September 23. The researchers planned to enroll 60,000 participants in the US and other countries.