U.S. biotech company Moderna on Wednesday announced initial data from a small clinical trial that showed its booster shots improved people’s immune responses against the major coronavirus variants of concern.
“We are encouraged by this new data, which reinforces our confidence that our booster strategy should be protective against these newly detected variants,” said the CEO of the company, Stéphane Bancel.
Forty participants were tested for their neutralizing antibody levels six to eight months after their primary vaccination series of two injections.
A third injection of the original Moderna vaccine or a variant-specific booster improved antibody levels against two major variants, which were first detected in South Africa and Brazil.
The variant-specific booster performed better than the original shot, producing almost twice as many neutralizing antibodies.
The company is also testing a third type of booster, which is a combination of the other two types, and plans to report the results soon.
Neutralizing antibodies are proteins produced by the immune system that are tailor-made to bind to a specific structure of a microbe.
In the case of the coronavirus, it is its spike proteins that dot the surface giving it its distinctive crown-like appearance.
Binding to these peaks prevents the virus from attaching itself and invading our cells.
Neutralizing antibodies are therefore important first lines of defense that prevent infection.
The immune system, however, contains many other key players which, especially among people vaccinated against the original virus or previously infected, can intervene and prevent serious disease, even if a variant enters and infects the host.
© 2021 AFP