Receiving a booster shot greatly increased the circulating number of antibodies including neutralizing antibodies - molecules that bind to the virus and stop it from infecting cells - against SARS-CoV-2, the virus that causes COVID-19.
The researchers tested nine different combinations of Johnson & Johnson, Moderna and Pfizer vaccines given to 458 participants and found that mixing was safe and highly effective. 15, a group of researchers presented the results from the study, which hasn't yet been peer-reviewed and is posted as a preprint to medRxiv, to an FDA panel of experts. The FDA's announcement to allow mixing and matching follows the early results of an ongoing National Institutes of Health (NIH) study.
