Moderna’s Covid-19 vaccine has been found to produce potent antibodies that last for at least three months. There also appears to be the potential for longer-term immunity, although that remains to be definitively proven.
The new study, published in the New England Journal Of Medicine, saw researchers at the National Institute for Allergies and Infectious Diseases (NIAID) test the immune response of 34 adult participants who received two doses of their vaccine, mRNA-1273, in their phase 1 trial. They then tested their level of various antibodies 90 days after the second vaccination (119 days after the first vaccination).
Even after three months, their blood still contained binding and neutralizing antibodies, suggesting they still had some immune protection against Covid-19.
That doesn’t necessarily mean the vaccine will stop working after 90 days, however. While longer-term studies will be needed to fully understand how long immunity persists, the study showed the vaccine sparked the response of a certain type of T cell that could suggest there is some longer-term immunity. These immune cells appeared just 43 days after the first vaccination.
“These interim Phase 1 data suggests that mRNA-1273, our Covid-19 vaccine candidate can generate durable neutralizing antibodies across all age groups including in older and elderly adults. Live virus and pseudovirus assay geometric mean titers (GMTs) remain high in the first months following vaccination,” Tal Zaks, PhD, chief medical officer of Moderna, said in a statement.
“These data give us further optimism to expect that the high level of efficacy recently demonstrated by mRNA-1273 to prevent Covid-19 disease will be durable.”
This news comes days after it was revealed that their vaccine was found to have an overall efficacy of 94.1 percent, with efficacy against severe Covid-19 of 100 percent. All in all, it’s looking very promising.
The US Food and Drug Administration (FDA) has announced that it will discuss the request for emergency use authorization for the Moderna Covid-19 vaccine on December 17. If this gets the green light, Moderna hopes to roll out 100 to 125 million doses of the vaccine in the first quarter of 2021.
Moderna’s vaccine is an mRNA vaccine. While most vaccines use a deactivated virus or a genetically modified virus, this new form of vaccination works by injecting a small fragment of the virus's genetic code, the mRNA, into the human body. This genetic code gives instructions for our cells to make a harmless piece of the virus’ “spike protein.” The body’s cells read these instructions and produce that harmless fragment. Once this piece of protein enters the bloodstream, our immune system is activated and it learns how to get rid of the virus. If the body comes into contact with a real SARS-CoV-2 virus in the near future, it will be ready to recognize the spike protein of the virus and launch an immune response.
Some have erroneously claimed that mRNA vaccines “rewrite” or “alter” your own DNA. However, that’s not true; mRNA never enters the nucleus of the cell, which is where our DNA is kept. Since the technology is relatively new, however, there are currently no licensed mRNA vaccines in the US.