The Chinese military has received the green light to use a Covid-19 vaccine. Developed by CanSino Biologics, it has not yet passed phase 3 of clinical trials.
China has just approved a vaccine against the SARS-CoV-2 coronavirus, named Ad5-nCoV. Developed jointly by a team from the Academy of Military Medical Sciences, led by Major General Chen Wei, and the Tianjin-based company CanSino Biologics, its use will be restricted to the Chinese military for one year. But is this preventive treatment effective?
The question arises indeed. And for good reason, if the Chinese authorities assure that the first data from clinical trials were sufficiently convincing, the fact is that this vaccine developed by the company CanSinoBio has not yet passed phase 3 of clinical trials. In other words, the treatment appears safe and appears to result in a relatively high immune response to the antigen (which has been proven in phase I and 2 trials). However, we do not really know if the vaccine can protect against SARS-CoV-2 infections
CanSino also declined to say whether the Chinese military would be required to receive the vaccine, or whether the injection would be optional, according to Reuters. Learn immune defenses to recognize the enemy
To develop their vaccine, the researchers started with a common strain of adenovirus (type 5). This usually only causes mild upper respiratory infections.
The researchers then “modified” the pathogens so that they can no longer replicate in human cells. They also made it possible for the latter to develop the signature of SARS-CoV-2: its famous advanced protein that allows the virus to take over our cells.
With this approach, the idea was therefore to present the immune system with a harmless virus, but equipped with the advanced protein of SARS-CoV-2, so that it can recognize it in the event of a new intrusion into the body. and release neutralizing antibodies.
In a phase 1 safety trial involving 108 people, the vaccine was therefore shown to be safe, as explained above. In addition, it has also stimulated the production of neutralizing antibodies and other immune responses.
However, the study, published in The Lancet, points out that people who had previously been infected with Ad5 in the past had developed a weaker immune response. This could be since their body quickly recognized the adenovirus, only to focus the defenses directly on the viral vector, rather than the advanced protein
CanSino also said it has already completed a larger phase 2 trial. However, the results have yet to be released, according to the South China Morning Post.
A phase 3 trial scheduled in Canada
Also, according to the newspaper, it seems that the company has already agreed with the Canadian government to conduct phase 3 trials there. However, no other information on the subject has been circulated yet. However, it is expected that these trials will examine the efficacy and potential side effects of the vaccine in an even wider group of subjects.