The COVID-19 vaccine by AstraZeneca and the University of Oxford was in Phase 3 testing on humans at dozens of sites across the US, but has been put on hold due to a suspected serious adverse reaction in a participant in the United Kingdom. There is no further information on the trial volunteer or their severe illness that may be due to vaccine injury. There are currently nine vaccine candidates in Phase 3 trials, and AstraZeneca is the first known to be put on hold. The unidentified injury has reportedly impacted vaccine trials by other manufacturers.

Stat News reports that the large, Phase 3 study testing a Covid-19 vaccine being developed by AstraZeneca and the University of Oxford at dozens of sites across the U.S. has been put on hold due to a suspected serious adverse reaction in a participant in the United Kingdom.