On the afternoon of April 14, the State Council’s Joint Defense and Joint Control Mechanism held a press conference. Wu Yuanbin, Director of the Department of Social Development and Technology of the Ministry of Science and Technology, and Wang Junzhi, academician of the Chinese Academy of Engineering, etc., interpreted the vaccine issues of public concern.
Wu Yuanbin, Director of the Department of Social Development Science and Technology of the Ministry of Science and Technology: China is the first to initiate the second phase clinical study of the COVID-19 vaccine
There are currently 3 vaccines approved for clinical trials in China. Among them, the adenoviral vector vaccine of the academician Chen Wei team was first approved for clinical research. A phase 1 clinical trial was completed at the end of March and recruitment began on April 9. Volunteers in Phase II clinical trials, this is the world’s first COVID-19 vaccine variety to initiate Phase II clinical studies.
On April 12, the State Food and Drug Administration approved the application of the inactivated COVID-19 virus vaccine jointly applied by the Wuhan Institute of Biological Products and the Wuhan Institute of Virology of the Chinese Academy of Sciences to enter clinical trials. On the 13th, Beijing Kexing Zhongwei Biotechnology was approved. The inactivated vaccine developed by the Co., Ltd. was launched for clinical trials. This was the approval of the inactivated vaccine for two consecutive days to carry out clinical trials.
Wang Junzhi, academician of the Chinese Academy of Engineering: China has a good basis for the development of inactivated vaccines
The two newly approved vaccines are actually a technical route and belong to the COVID-19 virus inactivated vaccine.
Among the vaccines developed and marketed in China, the H1N1 influenza vaccine, hepatitis A vaccine, EV71 hand, foot and mouth disease vaccine, and polio vaccine are all inactivated vaccines. Our country has a good foundation in the preparation of inactivated vaccines.
At the beginning of the epidemic, the earliest virus strains were isolated in China. At that time, the live virus had to be cultivated on a large scale. Through the joint prevention and control mechanism, the research and development unit was coordinated to use the P3 laboratory with a relatively high level of biological safety protection established in China to cultivate live virus in large quantities. So that our research and development has met the basic conditions.
Vaccine takes a big step towards application
Vaccine itself is from the completion of pre-clinical research to enter the clinic, this is a very significant progress, and it is a big step away from the future application.
The usual clinical trials are divided into three phases. The goals and significance of the three phases are different. According to different R & D programs, the time required is different.
The first phase of clinical trials focuses on the safety of observation and use. Mainly through a small number of susceptible healthy volunteers as subjects to determine the tolerance of the human body to different doses of the vaccine and to understand its initial safety, the general population size is relatively small, are dozens or 100 people.
Phase II clinical trials further expand the sample size and target population, the purpose is to further confirm the effectiveness and safety of the vaccine in the population, and determine the immunization program and immunization dose, which must be completed in the phase II clinical. Generally, the number of subjects is hundreds or more. It should be pointed out that the Phase I and Phase II clinical trials are aimed at healthy volunteers and are relatively easy to recruit. Depending on the immunization procedure and the different protocols, it may take several months.
True confirmation of the vaccine’s effectiveness requires a phase III clinical trial. A larger sample size is required for Phase III clinical trials. For general infectious diseases, it is generally necessary to observe an epidemic cycle to determine its protection rate for susceptible people. Its scale is several thousand people, and some even tens of thousands.
Generally after the end of the third phase of the clinical trial, the vaccine can obtain the scientific basis for approval. Even in emergency situations, our evaluation criteria for the safety and effectiveness of vaccines cannot be reduced. At present, the society pays close attention to vaccines, and we also look forward to seeing important breakthroughs in vaccine research and development in China as soon as possible, so that safe and effective vaccines can be launched as soon as possible.
Vaccination approval is so fast, is it really safe?
Vaccine itself is a special medicine for healthy people, safety is the first priority, so in the emergency approval process, always adhere to respect for science, follow the law, take safety and effectiveness as the fundamental policy, and insist on special affairs.
In this process, many R & D steps are changed from series to parallel, and research and review are linked, and the R & D materials are submitted on a rolling basis, followed by review and evaluation. On the premise of not lowering the standards, through seamless connection, the efficiency of research and development and the efficiency of evaluation are greatly improved, which are maximized, which is also the reason for the speed.
Can BCG prevent COVID-19?
The statement that “the time of BCG can reduce the possibility of getting COVID-19” is a rumor abroad. BCG vaccine is actually a vaccine for children’s planned immunization. It is widely used in our country. At present, we have not seen exact research data to support this claim, so we don’t know yet.