China.org.cn | January 4, 2021
China National Radio:
We would like to know, compared with foreign vaccines, what are the advantages of Chinese vaccines in terms of safety, efficacy and accessibility? How do we evaluate a vaccine comprehensively? Thank you.
Zheng Zhongwei:
Thank you for your question. Recently, I have noted that people are very concerned about the safety, efficacy and data published by the media in regard to the vaccines. There are many indicators for vaccine evaluation, and I think the very important ones include safety, efficacy, accessibility and affordability, among which safety and efficacy are the most important, as previous speakers have introduced. The safety of vaccines generally refers to whether there will be any adverse reactions and the severity of these after vaccination. The vaccines are considered safe if people don't experience adverse reactions, if they do, they aren't serious, or the probability of experiencing serious adverse reactions is quite low. As we all know, vaccines are special products for healthy people, so their safety is the first priority, which is the fundamental principle we have followed in advancing the research and development of vaccines.
Vaccine efficacy refers to whether people will be infected, or the level of severity of the infection if they are exposed to the pathogen after getting vaccinated. We consider the vaccine to be effective if the person vaccinated remains free from infection, or the infection is relatively mild. Therefore, some may find that when releasing efficacy data, some companies will also release a protection rate for severely ill patients. This is how we explain vaccine efficacy.
In the vaccine development process, we have tested the safety and efficacy of the vaccines on animals and humans on differing scales, based on animal tests, and phase I, phase II, and phase III clinical trials. As the introductions of speakers about China's vaccine research and development, a total of 14 vaccine candidates currently are undergoing clinical trials with five entering phase III clinical trials. These have been proved to be safe in the animal tests, and phase I and phase II clinical trials. Some of them have published the results in top medical journals around the world, and highly commended by the WHO. Besides safety and efficacy, accessibility and affordability of vaccines are also of prime concern. Only if a vaccine is safe and effective, and at the same time accessible and affordable, can the vaccine truly become a public good.
Talking about which vaccine is better, or comparing Chinese self-developed vaccines and foreign vaccines, I don't think we can draw any simple conclusions. The reason why we laid out the five technical routes in vaccine development is because each of them has its own advantages. Only by comprehensively reviewing the safety, efficacy, accessibility, and affordability of each vaccine can we achieve a scientific evaluation. For example, inactivated vaccines and recombinant protein vaccines, whose research and development are currently being advanced, have undergone tests by billions or even tens of billions of people for many years. Their safety, efficacy, and accessibility have stood the test of time and been proven through scientific methods. However, with the development of science and technology and of human society, there will be new vaccines developed using new technologies and methods in the future, which are better in terms of safety, efficacy, accessibility and other aspects.
The COVID-19 pandemic has made us more aware that humanity is a community with a shared future, and a community of health for all. In the process of advancing vaccine research and development, Chinese vaccine companies and teams have only one enemy, which is the virus. We are racing against the advance of the virus. Throughout the research and development process, we fully respect the laws and principles of science. China was the first country to launch clinical trials including phase III ones. In the process, we are strictly following relevant scientific principles, and will never compromise these principles in a rush to seek first place. This is our basic principle in the process of advancing vaccine research and development. Thank you all!