Eight months later: Researchers compare immune responses elicited by three COVID-19 vaccines

Eight months later: Researchers compare immune responses elicited by three COVID-19 vaccines: Based on the strength of clinical trial data showing the vaccines conferred robust protection against COVID-19, the U.S. Food & Drug Administration granted emergency use authorization to the mRNA-based vaccines known as BNT162b2 (BioNTech, Pfizer) and mRNA-1273 (Moderna) in December 2020, and to the Ad26.COV2.S (Johnson & Johnson) single-shot vaccine in February 2021. To date, nearly 200 million Americans have received a COVID-19 vaccine, and as some approach the one-year anniversary of their immunization, questions remain about the vaccines' long-term efficacy.