Chen Wei: recombinant COVID-19 vaccine effective against various novel coronavirus mutations

Source:China Military Online Editor:Chen Lufan 2020-09-08 17:35:19

A domestically produced inactivated COVID-19 vaccine displayed at the China International Fair for Trade in Services in Beijing. Photo: Li Hao/GT


By Zhang Yang and Yang Zhigang

Major General Chen Wei, a recipient of the title of “People’s Hero”, an academician with the Chinese Academy of Engineering and a researcher at the Institute of Military Medicine under the Academy of Military Sciences, was interviewed recently on the R&D and application of COVID-19 vaccines in China that the public is most concerned about.

“What are the features of the recombinant novel coronavirus vaccine developed by the Academy of Military Sciences?”

Gen. Chen Wei: We have independent intellectual property over the vaccine, which means we can decide on our own matters concerning its development and its production and application later. This way we can make sure the general public will have quick access to it at a lower price when they need it.

This is an advanced viral vector vaccine. We began the phase-I clinical trial on March 16, the first in the world, and published the test data on The Lancet on May 22, showing that all 108 volunteers had produced antibodies against the novel coronavirus after vaccination. The editor-in-chief of The Lancet commented that “the vaccine is safe, well-tolerated and a single injection induces a rapid immune response. These results represent an important milestone.” By then, we shared the testing methods and indicators with the whole world, so researchers in other countries can accelerate their vaccine development.

On July 20, we first announced the phase-II clinical trial data in the world. Results from phase-I and II clinical trials proved the vaccine’s effectiveness and safety. We began to vaccinate certain people in June.

The phase-III clinical trial is progressing smoothly. As the pandemic is well under control in China, we have to carry out the phase-III test overseas to verify the vaccine’s effectiveness and safety on a larger scale.

“How long will it take to market the vaccine on a large scale after the successful phase-III clinical trial?”

Gen. Chen Wei: The development of a vaccine generally takes three phases of clinical trial and mass production will only begin after the testing results meet certain standards and requirements. But preparations have been made for mass production of the recombinant vaccine from phase-I. At present, we are able to produce 300 million doses of vaccines a year and efforts are being made to expand the production capacity. Production will catch up after phase-III test results come out, so we’ll be technically and seamlessly prepared to vaccinate the people extensively.

“How long will the recombinant COVID-19 vaccine stay effective after being injected?”

Gen. Chen Wei: It’s only been half a year or so since we separated the coronavirus strain, so the world doesn’t have much data yet about how long the vaccine will stay effective as the data are all within a year. Our vaccine was the first to enter phase-I clinical trial in the world - in March, so the data we have is only half-year long. So far the injection taken in March is still effective, and we are still studying how much longer it will remain so. At the moment, we can only estimate based on the experience with previous similar vaccines. For instance, the Ebola vaccine will have less immunity effect six months after injection, but a second injection at the six-month point will remain effective for another two years. We can refer to these data.

“Will the vaccine become ineffective in case of coronavirus mutation?”

Gen. Chen Wei: The vaccine we developed is genetically engineered. In other words, we found the most useful section of genes and turned it into a vaccine. Analysis of current data indicates a very low possibility of variation in the section of genes we chose. So far the recombinant COVID-19 vaccine is able to cover mutated novel coronavirus.

Moreover, since the vaccine is a genetically engineered one, once it becomes less effective on mutated virus, we can use it for basic immunity and quickly develop a more targeted vaccine for enhancement, like a software patch-up. That’s why so many countries in the world are working on genetically engineered vaccines. It is a new-generation technology and a rising one that should be energetically supported in the future.

“Globally speaking, how do you think China’s COVID-19 vaccine R&D?”

Gen. Chen Wei: Undoubtedly China is among the first echelon in COVID-19 vaccine R&D as more than half of vaccines entering phase three clinical trials made public by the WHO are developed in China. That speaks volumes.