Scientists at Johnson & Johnson are refuting a claim that the design of their COVID-19 vaccine is causing the very rare brain blood clots in some individuals inoculated with their vaccine.
The extremely rare clots were also observed on the vaccine made by AstraZeneca which happens to be using the same technology as the J & J vaccine.
Both vaccines are using a modified version of adenoviruses as vectors to ferry instructions to human cells, which lead to some experts concluding that the vaccine technology is causing the rare condition.
Macaya Douoguih, a scientist at J&J’s Janssen vaccines division stressed that the vectors used in the Jannsen jab and the AstraZeneca shot are “substantially different” adding that those differences could lead to “quite different biological effects.”
The scientist said AstraZeneca is using a chimpanzee adenoviral vector vaccine while Janssen employs a human adenoviral vector vaccine.
The J&J scientists said in the letter to the New England Journal of Medicine that there is no sufficient evidence to conclude that their vaccine is causing the clots.
The US federal health regulators on Tuesday halted the administration of the company’s Jannsen Vaccine to probe the six cases of blood clots reported to those who have received the shot.
The rare condition, identified as cerebral venous sinus thrombosis (CVST), is accompanied by a low blood platelet count and appears to affect women below 50.
According to a New York Times report, one has died, and another one is in critical condition.
Meanwhile, the vaccine manufacturer said it will continue to work with the US Food and Drug Administration and US Centers for Disease Control and Prevention. (RA)