Studies from Chinese researchers indicate that the third dose of CoronaVac, a vaccine made of inactivated viruses from Butantan and Sinovac, produces antibodies capable of recognizing the omicron variant. According to the scientist Xiangxi Wang, main researcher of the Infection and Immunity Lab of the Biophysics Institute from the Chinese Academy of Science, his group performed a screening of more than 500 units of neutralizing antibodies obtained after the third dose. The theme was raised this Wednesday (8) during the CoronaVac Symposium.
“Around one third of the antibodies presented great ligation affinity with the Spike protein from the strains of concern, including the Omicron, that have more than 30 mutations”, he affirms. The researchers will still test the capacity of neutralizations of these antibodies against the virus to confirm its efficacy. “But I believe that at least the inactivated vaccines can still work and protect against the omicron variant, without the need of an update.”
For the researcher Alexis Kalergis, immunologist of the Pontifical Catholical University from Chile, the evidence shows that the booster dose is a way to potencialize the immune response against the variants. However, he believes that the vaccines must be updated so it can undeniably cover the strains of concern. “Here in Chile, our purpose is to administer the booster dose. The third dose of the CoronaVac results in levels of T cells much higher than the levels at the second dose, and that is important to fight against the virus and its mutation”.
Sinovac is already working on the update of CoronaVac against the Omicron variant. The researchers will isolate the virus from samples of patients from Hong Kong to initiate the tests of neutralizing antibodies. Afterwards, a clinical trial will be made to evaluate the efficacy of the immunizing. The estimate is for this whole process to take at least three months.