WASHINGTON – The Moderna Covid-19 vaccine, which the company says was recently demonstrated to have 94% efficacy, causes the human immune system to produce potent antibodies that endure for at least three months, a study showed yesterday.
Researchers at the National Institute for Allergies and Infectious Diseases (NIAID), which co-developed the drug, studied the immune response of 34 adult participants, young and old, from the first stage of a clinical trial.
Writing in the New England Journal of Medicine, they said that the antibodies, which stop the SARS-CoV-2 virus from invading human cells, “declined slightly over time, as expected, but they remained elevated in all participants three months after the booster vaccination”.
The vaccine, called mRNA-1273, is administered in two injections given 28 days apart.
Even though the number of antibodies in the study subjects faded over time, it is not necessarily a cause for concern.