Oxford Coronavirus Vaccine Put on Hold

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Leading vaccine research company, AstraZeneca, and the University of Oxford have paused their clinical trials due to a participant’s adverse reaction in the U.K. 

Across the world, the leading contender for creating the widely-anticipated COVID-19 vaccine is the AstraZeneca-Oxford vaccine. The research is in Phase 3, one of its final stages, consisting of human clinical trials. The clinical trial’s 30,000 participants span worldwide, with volunteers from the U.S, U.K, Brazil, South Africa, and more.

However, clinical trials have been paused due to a patient’s adverse reactions in the U.K. According to the chief executive of the drug, Pascal Soriot, the participant was “A woman in the United Kingdom who experienced neurological symptoms consistent with a rare but serious spinal inflammatory disorder called transverse myelitis.”  Soriot confirmed that the trial was also halted again in July, with another participant suffering from multiple sclerosis, which was unrelated to COVID-19.


When an illness arises in a vaccine trial like this, temporarily pausing trials to figure out the source of the problem follows standard protocol. Astra-Zeneca put out a statement on September 9 stating, “This is a routine action which has to happen whenever there is a potentially unexplained illness in one of the trials, while it is investigated, ensuring we maintain the integrity of the trials.”

They further commented: “At AstraZeneca, we put science, safety, and the interests of society at the heart of our work. This temporary pause is living proof that we follow those principles while a single event at one of our trial sites is assessed by a committee of independent experts. We will be guided by this committee as to when the trials could restart so that we can continue our work at the earliest opportunity to provide this vaccine broadly, equitably, and at no profit during this pandemic.”

Astra-Zeneca has not released any information on when they will be resuming their clinical trial studies. Assuming the trial resumes soon and Phase 3 is successful, we could have a vaccine for the public as early as the end of 2020.