Trials of the British vector vaccine against coronavirus, which is in the third stage of clinical trials, have been suspended. The cause was an unexplained illness of one of the volunteers: presumably transverse myelitis. Now scientists are finding out whether the disease can be considered a side effect of vaccination or it is not associated with trials, according to the publication STAT.
The third phase of clinical trials of the COVID-19 vaccine, which is being developed by the University of Oxford and AstraZeneca, started in the United States at the end of August; as part of these trials, it is planned to vaccinate about 30 thousand people. This is a vector vaccine based on chimpanzee adenovirus: similar vaccines based on other adenoviruses are currently being developed in China and Russia at NITSEM. Gamalea.
The British have already reported on the results of the second phase of the study: there are no serious side effects of the vaccine, and it is quite effective in inducing an immune response. In addition to the third-phase trials, an interim vaccine testing (phase 2/3) has been taking place since May, which will allow us to understand the impact of the vaccine on different age groups. It takes place in the UK: about ten thousand people take part in it.
On Tuesday, the vaccine trials were suspended: all planned vaccinations have been postponed indefinitely. The reason was an acute condition of one of the volunteers of phase 2/3. According to the New York Times, this is transverse myelitis — an inflammation of the spinal cord, often associated with viral infections and autoimmune diseases. More precise information about the patient's health is not yet available, and it is not known whether his illness is related to the trials or whether it is an independent process.
AstraZeneca commented that suspending testing is a common action when a case of unexplained illness occurs. Such events are not uncommon, and in studies with a large number of participants, such cases often occur simply by chance. However, until the nature of the malaise is determined, further vaccination is postponed.
The creators of the Russian adenovirus vaccine against coronavirus recently published the results of 1/2 stages of clinical trials, in which 76 volunteers took part.
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