CanSinoBIO using same technique as Johnson & Johnson reports no blood clots
Chinese vaccine producer CanSinoBIO said on Wednesday that it had not received any report of blood clots after vaccination of about a million people with its recombinant adenovirus vector COVID- 19 vaccine, amid reports of inoculation suspension in various countries for AstraZeneca and Johnson & Johnson’s COVID- 19 vaccines, which use the same technical method as CanSinoBIO.
CanSinoBIO said that, although its vaccine uses the same technique, it uses different adenovirus than the other two companies. CanSinoBio uses adenovirus type- 5 as vector, a common adenovirus among humans, while AstraZeneca uses chimpanzee adenovirus and Johnson & Johnson uses adenovirus type- 26.
Despite the blood clot issue, Chinese experts said it does not necessarily mean that the technique is to blame, noting that Russia and China have also administered such vaccines but no serious clot cases have been reported.
The human body usually produces platelet- associated antibodies after accepting vaccines. Such antibodies can promote the coagulation of platelet, which possibly could lead to blood clots. But it is still unclear why such antibodies would occur after vaccination, a Beijingbased immunity expert who requested anonymity told the Global Times on Wednesday.
The expert noted that blood clots are a very rare side effect of vaccines. Seemingly no similar report of blood clot related to any commercial vaccine had been reported before the COVID- 19 pandemic.
Another possible reason lies in the process of production. It could be a lacking of experience or the problem of materials, the Beijing- based anonymous expert said, referring to media reports in March that said workers at a US manufacturing subcontractor of both AstraZeneca and Johnson & Johnson mixed ingredients of the two’s vaccines.
The problem is that firstclass producers such as Merck or GSK are not involved in COVID- 19 vaccine. So the serious side effects reported after vaccination in the West could be related to limited production conditions and inexperience of the producers, the anonymous experts said.