evidence: There are two COVID-19 messenger-ribonucleic acid (mRNA) vaccines currently authorized for emergent use in the United States: the Pfizer-BioNTech and the Moderna vaccines. Conventional vaccines rely on weakened and inactivated pathogens or a fragment of the pathogen to trigger an immune response. In contrast, the COVID-19 mRNA vaccines use a new approach by which mRNA is delivered into our cells to provide the genetic instructions for our own cells to "temporarily" make a "specific" viral protein (the coronavirus spike protein) that triggers an immune response. [...] The Pfizer-BioNTech COVID-19 vaccine is made of the following ingredients: [...] - mRNA – Like the Pfizer BioNTech vaccine, Moderna’s also uses mRNA technology to build antibodies against COVID-19.