Source of this article: Times Finance Author: Zhao Pengyu
AstraZeneca The "thrombosis" of the new crown vaccine is still full of doubts.
Image source: Tukong
On April 7th local time, the European Medicines Agency (EMA) and WHO successively issued statements saying that the AstraZeneca vaccine may be related to rare thrombosis.
However, EMA has made it clear that abnormal thrombosis symptoms with thrombocytopenia should be classified as a "very rare side effect" of the AstraZeneca vaccine, but the overall benefits of getting the vaccine outweigh the risks, and specific risk factors such as age, gender and history of thrombosis cannot be confirmed.
In response to the AstraZeneca vaccine thrombosis association issues and company-related investigation results, Times Finance asked a relevant person in charge of AstraZeneca (China) on April 8, but he said "no official reply yet."
According to EMA Safety Committee Chairman Strauss, as of early April, 169 reports of cerebral blood clots have been found in the injection of 34 million doses of AstraZeneca vaccine in the European Economic Area.
As more and more evidence shows that the AstraZeneca vaccine may cause blood clots, the British drug regulator proposed on April 7 local time to suspend the injection of AstraZeneca vaccine for people under 30 years old. This age group will instead inject Pfizer or Moderna vaccine. At the same time, European countries such as Italy, , Belgium, and have also suspended vaccination or adjusted the scope of the population for the AstraZeneca vaccine.
vaccine expert Tao Lina told Times Finance on April 8 that the thrombosis association problem of AstraZeneca vaccine still needs to be confirmed after further research. "At present, nearly 200 million doses of AstraZeneca vaccine are used worldwide, and there are less than 100 confirmed cases of thrombosis and thrombocytopenia. Even if all of them are caused by the vaccine, the risk of thrombosis after vaccination is about 4 in one million, which is almost negligible with the benefits obtained by vaccination. You must know that even conventional vaccines are acceptable for the risk of a probability of less than one in one hundred thousand."
thrombosis may be related to vaccines?
Although AstraZeneca's new crown vaccine has passed safety certification in more than 70 countries around the world, since the second half of 2020, the vaccine has been controversial due to side effects, falsification of clinical data, etc. Now the problem of coagulation side effects has once again pushed AstraZeneca to the forefront of public opinion.
The UK is currently one of the fastest countries in the world to receive the new crown vaccine. About 31.7 million people have received the first dose of the vaccine and 5.7 million people have received the second dose of the vaccine, most of whom are given the AstraZeneca vaccine.
According to the UK's Drugs and Health Products Agency, as of the end of March, about 20 million people in the UK had received the AstraZeneca vaccine, 79 of whom had blood clots and 19 died. Among the 19 dead, three were under 30 years old.
Due to the increasing number of cases of thrombosis patients, in March this year, nearly 20 countries around the world successively suspended the AstraZeneca vaccine. In this regard, EMA and other institutions launched an investigation into the AstraZeneca vaccine thrombosis problem.
At that time, EMA repeatedly stated that in the case of investigation and reporting, they believed that the benefits of injecting the AstraZeneca vaccine outweighed the risks. The World Health Organization also supports the continued use of the vaccine. Subsequently, European countries have resumed vaccination.
However, on April 7 local time, the World Health Organization (WTO) Consulting Vaccine Safety Group, the European Union and EMA and other authoritative agencies issued statements saying that there is a "reasonable" causal relationship between the AstraZeneca vaccine and the side effects of coagulation in the vaccinated person, but more work still needs to be done to determine the cause of thrombosis.
UK Deputy Chief Medical Officer Jonathan Van-Tam said that the incidence of thrombosis after vaccination is higher than that of the elderly. Given that young people are less likely to die from the new crown than older people, the UK Joint Committee on Vaccination and Immunization said that it is best for people under 30 to get alternative vaccines.
At present, many countries have adjusted their vaccination plans.
In addition to the UK, Belgium has also announced that it will temporarily vaccinate people aged 18 to 55 to receive the AstraZeneca vaccine, and another vaccine will be replaced.Italy, France, Germany, , Netherlands have previously set age restrictions on getting the AstraZeneca vaccine.
In addition, the South Korean government has decided to temporarily postpone the AstraZeneca vaccination work originally scheduled to be carried out for specific groups from April 8, and suspend the vaccination of people under 60 years old.
Oxford University suspends clinical trials of AstraZeneca vaccine for children
The continuous fermentation of the "thrombosis gate" has greatly affected this new coronavirus vaccine jointly developed by AstraZeneca and Oxford University. Oxford University issued a statement on April 6 saying that it has suspended small-scale clinical trials for children and adolescents vaccination in the UK. They said they are waiting for more data on the thrombosis investigation.
In February this year, the University of Oxford released a plan to recruit 300 subjects aged 6 to 17 in the UK. The trial is intended to evaluate whether the vaccine can produce a strong immune response in children aged 6 to 17. More than 200 volunteers aged 6 to 17 will receive the AstraZeneca vaccine. At present, Oxford University has not announced how many people have been vaccinated in the trial.
In response to this, a spokesperson for the University of Oxford said that there were no safety issues during the trial, but the thrombosis symptoms of some adults of AstraZeneca vaccine have caused widespread concerns. British regulators have begun an investigation into this, and Europe is also investigating the link between vaccines and blood clots.
The spokesperson also said that the University of Oxford is waiting for more information from the UK regulators that children or adolescents will not be vaccinated with AstraZeneca vaccine in trials.
Since this year, many pharmaceutical companies including AstraZeneca, Pfizer, and Moderna have launched new crown vaccine trials for children, hoping to vaccinate children as soon as possible.
According to the British " Daily Telegraph " on March 23, the relevant safety data of the AstraZeneca vaccine is expected to be released soon, and British children are expected to start vaccination of the new crown vaccine as early as August.
However, with the emergence of thrombosis side effects and the suspension of clinical trials for children, it is still unknown whether AstraZeneca's plan to start vaccinating British children with the new crown vaccine in August can be realized.
At present, clinical trials of the expansion of the age group of new crown vaccination for companies such as Pfizer and Moderna to children are still underway.
In March this year, Pfizer said it had begun clinical trials of the new crown vaccine for healthy children aged 6 months to 11 years old. According to details released on the clinicaltrials.gov website, Pfizer is testing three different doses for children aged 11 and under. 144 people participated in the first and second phase trials, which will be expanded to 4,500 later.
It is reported that the trial aims to determine the appropriate vaccination doses for three young children's age groups (6 months to 2 years old, 2 years to 5 years old, and data is expected to be obtained in the second half of 2021. In addition, Pfizer is also testing the effectiveness of the vaccine on children aged 12 to 15, and data is expected to be disclosed in the next few weeks.
