Testing of one of the world’s leading COVID-19 vaccine candidates has been interrupted due to safety concerns. A vaccine trial in the last phase has been suspended following the suspicion of a serious adverse reaction to the drug in one UK participant.
The test vaccine, developed by the pharmaceutical company AstraZeneca in collaboration with scientists from the University of Oxford, was considered a leader in the global race for safe and effective immunization to protect against SARS-CoV-2 infection.
Researchers expect the test subject to recover, but it is unclear how the incident will affect the future development of the Oxford vaccine. AstraZeneca shares fell immediately after news of the failure spread. The suspension of trials could affect not only the AstraZeneca vaccine, but also clinical trials by other manufacturers and countries.
Although the vaccine makers did not disclose the details of the potential adverse reaction, the company raised concerns, stressing that the suspension of trials is a routine process and can only be caused by one such event.
About 50,000 people are reported to have participated in the candidate vaccine trials.