On September 8, many media in the United States reported that the high-profile British pharmaceutical company AstraZeneca and Oxford University jointly developed the new crown virus vaccine AZD1222, which was in the third phase of clinical trials, was suspended because of a The British subjects experienced severe side effects.
The Covid-19 vaccine jointly developed by British pharmaceutical companies AstraZeneca and Oxford was stopped. According to a person familiar with the matter, the nature of this side effect and when it occurred are still unclear, but the participant is expected to recover. An AstraZeneca spokesperson stated that the suspension of clinical trials is "a routine action that must be taken as long as there are diseases of unknown cause during the trial process to ensure the impartiality of the trial."
, a British Covid-19 vaccine subject AstraZeneca suspends vaccine trials for unexplained diseases.
AstraZeneca was once considered to be the leader in the global COVID-19 vaccine research and development competition. It is expected to meet the requirements of US President Trump. It will be put into use before the US election in November. In an interview with Fortune Magazine on August 10 this year, Sleecom CEO Pascal Soriot mentioned that its new crown virus vaccine AZD1222 has undergone phase three clinical trials in the United Kingdom, Brazil and South Africa, and will soon be in The United States started. The purpose of these tests is to verify the immune system's response to the vaccine. Due to the unpredictability of Covid-19, Sorio mentioned that if clinical trials prove that the vaccine is successful, in order to get immunity, each person may need more than one shot of the vaccine. The suspension of
clinical trials is not uncommon, and it is unclear how long it will take AstraZeneca to be suspended and investigate. However, in view of the urgent need to contain the global pandemic, the company's test progress, as well as the progress of all Covid-19 vaccines under development, are closely watched by the world. There are currently nine candidate vaccines undergoing Phase III clinical trials. The AstraZeneca vaccine is the first known phase III Covid-19 vaccine trial that has been shelved.
AstraZeneca CEO Pascal Sorio was mentioned in an interview with Fortune Magazine that the company’s biggest challenge is to produce 2 billion doses of the Covid-19 vaccine
. The Inclusive Vaccine Alliance has reached an agreement to provide up to 400 million doses of vaccine. The company's goal is to produce a total of 2 billion doses of vaccine, of which 400 million doses are used in the United States and the United Kingdom, and 1 billion doses are used in low- and middle-income countries. How does
judge whether the COVID-19 vaccine is effective and safe? How does
judge whether the COVID-19 vaccine is effective and safe?
There are several vaccines currently undergoing large-scale research and clinical trials around the world to determine whether they can prevent COVID-19. President Trump has been hinting that the vaccine may be ready before the general election at the end of October. Is the truth really like this?
Moncef Slaoui (Moncef Slaoui) is the chief scientific adviser of the Trump administration's "Warp Speed" operation. He was cautious about this in an interview with the famous American radio station NPR.
Slavi said: "The possibility that the various COVID-19 vaccine trials currently underway can be put into use before the end of October is very, very low." Slavi said about the large-scale vaccine effectiveness research currently discussed. Some common questions are answered as follows:
Q: What is the scale of these ongoing clinical trials?
A: The purpose of the trial is to recruit at least 30,000 volunteers in each clinical trial. Half of them will be injected with the candidate vaccine, and the other half will be injected with a placebo. These volunteers did not know that they were given a vaccine or a placebo. Therefore, neither group of people has any predictions about the final result. Studies like this are called double-blind, placebo-controlled trials, and they are generally considered to be the best design to get definitive answers.
To test the effectiveness of the vaccine, researchers need to vaccinate enough people and then expose these people to the virus. But when the researchers prepared to test their vaccine, they were not sure where the virus would spread. Therefore, the researcherThe player bet on both sides and selected a large number of samples.
Q: How is the success of the vaccine trial determined?
A: through large-scale trials, researchers hope to understand whether this vaccine is safe and whether it can prevent infection. The initial safety study of
was done by testing a small number of healthy volunteers. Then conduct large-scale trials to find less common side effects. To determine whether the vaccine is effective, the researchers will compare the number of infections in people receiving live vaccines and people receiving ineffective placebos.
The Food and Drug Administration (FDA) is the federal agency that ultimately decides whether to authorize the use of vaccines. The FDA stated that the prerequisite for considering the use of a vaccine is that the vaccine must reduce the infection rate of the vaccinated population by at least 50%.
Q: When will we know if a vaccine is effective?
A: This is not clear. This is the so-called event-driven test: "An event-driven test means that a preliminary analysis of the test will only be performed when enough events occur." Here, "event" refers to a laboratory-confirmed case of COVID-19.
Holly Janes, a biostatistician at the Fred Hutchinson Cancer Research Center in Seattle, said we don’t know how long such an event-driven trial will take. Janes said that the ongoing trial is designed to allow at least 150 of the trial volunteers to be infected and diagnosed with the new coronavirus. To ensure that the researchers do not know who is receiving the vaccine and who is taking the placebo, an independent agency will track the data as it is collected. The data security monitoring committee is composed of experts in all aspects of clinical trial design and implementation.
Q: What are the disadvantages of the premature launch of the COVID-19 vaccine?
A: If the vaccine does not work, people will continue to get sick and die. Only a 50% effective vaccine still means that people may be infected with COVID-19, but even a partially effective vaccine will make the pandemic easier to control.
has launched a vaccine with serious side effects. Even if it is a rare side effect, it means that if a perfectly healthy person is vaccinated, their health will be at risk. If the vaccine is considered a failure by the public, it will undermine public confidence in the government.
Q: What vaccines are currently undergoing clinical trials and how do I sign up?
A: All vaccines tested in the United States can be found on the government website: ClinicalTrials.gov.
Three pharmaceutical companies Moderna, Pfizer (Pfizer) and AstraZeneca (AstraZeneca) are currently conducting large-scale research trials. Johnson & Johnson and Novavax should begin their large-scale trials in the next month or two.
