The recombinant new coronavirus vaccine (adenovirus vector type 5) (Ad5-nCoV) KeweishaTM developed by CanSino Biology and the team of Academician Chen Wei of the Academy of Military Sciences was approved for conditional listing in China on the 25th of this month. Yu Xuefeng, chairman of CanSino Bio, revealed at a media communication meeting on February 28 that after the increase in production capacity of the Tianjin plant with an annual output of 200 million to 250 million doses of vaccine, he believes that this new crown vaccine will be launched in the domestic market in large quantities. I hope it can be used in all provinces and cities across the country in the next few months.
According to CanSinoBio’s previous announcement, the results of the interim analysis of the Phase III clinical trial of KeweishaTM showed that 28 days after a single injection of the vaccine, the overall protective efficacy of the vaccine against all symptoms was 65.28%; the single injection of the vaccine 14 After days, the overall protective efficacy of the vaccine against all symptoms was 68.83%. The protective effects of the vaccine on severe illnesses were as follows: 90.07% after 28 days of single-dose vaccination; 95.47% after 14 days of single-dose vaccination. According to Yu Xuefeng, clinical trial data showed that cellular immunity reached a peak 14 days after vaccination with Keweisha TM vaccine, and humoral immunity reached a peak at 28 days, showing that cellular immunity played a great role in it.
CanSino Bio’s new crown vaccine will fully launch a global multi-center Phase III clinical trial in September 2020. Yu Xuefeng introduced that the conditional listing of Kevisa TM is based on the interim data of the Phase III clinical trial of more than 100 subjects. At present, clinical trials have reached the previously set target of at least 150 subjects, and relevant data are yet to be released.
Unlike the other three domestic vaccines that have been approved for conditional marketing, which require those who are between 18 and 59 years old, CanSino Bio-Vaccine can be vaccinated by adults 18 years and older, including the elderly. Yuxuefeng said on the same day that Keweisha TM has not set an upper limit on the age since the second phase of the clinical trial. The oldest volunteer is 84 years old. Statistics show that, globally, nearly 10% of the elderly are enrolled in the KevisaTM Phase III clinical trial. In an interview with the media a few days ago, Academician Chen Wei also revealed that clinical trials for vaccines between 6 and 18 years old have been completed, safety data are available, and the Food and Drug Administration is still reviewing.
It is also an important feature that Keweisha TM requires only one injection. Yu Xuefeng said that a single shot can provide dual protection of humoral immunity and cellular immunity, so that more people can be protected as soon as possible, which is very valuable for controlling the pandemic. Academician Chen Wei revealed that up to now, the protective effect of the vaccine can last for 6 months. At the same time, a booster immunization test after 6 months has been done. After another injection, the immune response can be increased by 10 times and 20 times. With reference to previous relevant data, the researchers speculate that after boosting the immunization, the immunity of the vaccine can last for at least 2 years.