Moderna has created the first “tweaked” vaccine, which it says is effective against Covid-19 variants.
Early data from a 40-person trial show that a third dose of either its current Covid-19 jab or an experimental new vaccine candidate increases immunity against variants first found in Brazil and South Africa.
“We are encouraged by these new data, which reinforce our confidence that our booster strategy should be protective against these newly detected variants,” said the company’s CEO Stephane Bancel.
Forty participants were tested for their levels of neutralising antibodies six to eight months after their primary vaccination series of two shots.
A third shot of either 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 neutralising antibodies.
The US biotech firm is also testing a third type of booster, which is a combination of the other two types, and plans to announce results for it soon.
Neutralising antibodies are proteins produced by the immune system that are custom-made to bind to a specific structure of a microbe.
In the case of the coronavirus, these are its spike proteins that dot the surface giving it its distinctive crown-like appearance.
Binding to these spikes prevents the virus from latching on to and invading our cells.
Neutralizing antibodies are therefore important first lines of defense that prevent infection.
The immune system does however contain many other key players which, especially among people who were vaccinated against the original virus or previously infected, can kick in and prevent severe disease, even if a variant breaks through and infects the host.
Read more: How the Moderna, AstraZeneca, Pfizer and other Covid vaccines compare
Source link