Delta'S Fierce Competition For Vaccine Research And Development

Delta, a new coronavirus variant, is coming.

According to the World Health Organization Research, delta virus has a fast transmission speed, rapid replication in vivo, and a long time to turn negative. Compared with other non VOC and old virus strains, its transmission rate has increased by nearly 100%, that is, doubled. According to the Health Commission, Delta has been prevalent in more than 130 countries and regions, and it is the main virus strain in the global new coronal pneumonia pandemic.

Vaccines are the key to overcoming the epidemic. Feng Zijian, a researcher at the Chinese Center for Disease Control and prevention, said that the incubation period and generation interval of Delta have been shortened. If there is no strong prevention and control measures to intervene and if there is no vaccine immunization to prevent its spread, the doubling speed of the epidemic situation will be very significant. In the past, the number of patients increased by two to three times every four, five or six days. Now, there may be five, six or seven times more patients in about three days.

In view of the variant strain of delta, domestic vaccine enterprises have already started the related vaccine research and development work. Recently, enterprises have announced their R & D progress.

Existing vaccines are still effective

Sinopharma China biology announced on the afternoon of August 4 that researchers Yang Xiaoming's team had recently discovered an effective monoclonal antibody against delta mutant strain, with neutralizing activity IC50 as high as 5ng / ml.

As soon as the news came out, the shares of two listed companies of Sinopharm group were in line with that of Sinopharm. The shares of Sinopharm once rose by more than 8%. Faced with the enthusiasm of the market, Sinopharm issued a statement before trading on August 5 that the company's main business is pharmaceutical wholesale, which does not involve the R & D and production of vaccines and drugs. The R & D and production of vaccines and drugs belong to China Pharmaceutical Group Co., Ltd., the actual controller of the company, and the main business of the company has not changed significantly.

On the same day, Kangtai biological also said that the vaccine research and development project for the new coronavirus mutant has made important progress, and has successfully isolated a number of delta mutant monoclonal strains. In the follow-up, the virus strains will be evaluated in strict accordance with the quality requirements of human vaccines, and the vaccine strains will be screened, so as to prepare for the production of new crown inactivated vaccine against delta mutant strains. Stimulated by the news, Kangtai biological early trading on August 5 was higher than 15%.

As the first two new crown inactivated vaccine companies to enter the conditional listing in China, Kexing biology and Zhongsheng group also announced their latest progress to the society.

So, is the existing vaccine still useful for Delta?

He Qinghua, a first-class inspector of the disease control bureau of the National Health Commission, said that the relevant scientific research and epidemic prevention and control practice at home and abroad showed that the delta mutation did not cause subversive changes in the biological characteristics of the new coronavirus, the source of infection and transmission path were basically clear, and the existing epidemic prevention and control measures were still effective for the delta variant. The existing vaccines still have good preventive and protective effects, which can reduce the risk of virus transmission in the population, reduce the transmission power of infected people, and effectively reduce the severe incidence and mortality after infection.

Zhong Nanshan, academician of the Chinese Academy of engineering, also responded to the doubts about the effectiveness of the vaccine. He made it clear that according to the laboratory results, the overall killing power of some vaccines on the virus has decreased, but it still has a protective effect, and uses a set of verified scientific data to illustrate. According to the clinical immune results, the positive conversion rate of the immune serum inoculated with kexingxinguan inactivated vaccine decreased slightly to 87.5%; However, the neutralization ability of Chinese medicine vaccine to alpha strain decreased by 6.7%, and the protective ability remained unchanged; The neutralization ability of beta strain and delta strain decreased by 47% and 32% respectively.

According to the research report recently released by Guoxin Securities, humoral immunity is the main way to prevent new coronavirus infection. New coronavirus infection or vaccination can produce considerable humoral immune response. The level of neutralizing antibody decreases slowly with time, but it can still maintain above a certain protection threshold for several months.

The ability of transmission and pathogenicity of delta mutants has been enhanced, the neutralization antibody titer threshold required for infection prevention has been increased, and the protection duration has been shortened. Therefore, high protective vaccines are urgently needed to cope with the new wave of epidemic situation brought about by delta mutant strains.

New vaccines are not available overnight

In fact, although researchers are carrying out related research day by day, the research and development of vaccine is an extremely scientific and rigorous process.

Generally speaking, the process of vaccine research and development is divided into five steps: vaccine source acquisition, production process research, quality research, animal experiment and clinical research. Therefore, it takes an average of 8-10 years from the start of research and development to the completion of three phases of clinical trials.

Due to the sudden and emergency of the new coronavirus, the research and development of new coronavirus vaccine has been the fastest so far. It took nearly a year for many new coronavirus vaccines at home and abroad from project approval to mass vaccination. Although domestic vaccine companies have carried out relevant research on the mutant strains and the enthusiasm of the capital market is high, there is still a way to go before the new vaccine is put on the market.

"Taking Kangtai biological Co., Ltd. as an example, it has successfully sorted out the delta mutant strain. Now, it is only the most basic raw material for the development of a new inactivated vaccine of delta mutant strain. However, it is still necessary to design the vaccine according to the characteristics of the virus. It can only be said that the long march has just begun. Kangtai biological official public number vaccine science base previously stated that it would take 8 years or even more than 20 years. According to its disclosure, the current work is still in the early stage of research and development. " A disease control professional in Guangdong told the 21st century economic report that "at present, in addition to carrying out very important vaccine injection, the prevention and control strategy mainly uses big data and other means to find out the activity track of infection cases, inform relevant personnel of the risk of exposure, and combine with the active nuclear acid inspection and screening to curb the spread of the virus at the fastest speed."