On Feb. 8, 2021, Pfizer and BioNTech announced publication in Nature Medicine of data from in vitro studies that demonstrated that sera from individuals vaccinated with the Pfizer-BioNTech COVID-19 vaccine neutralized SARS-CoV-2 with key mutations present in the United Kingdom and South African variants.

These data, based on studies conducted by Pfizer and the University of Texas Medical Branch (UTMB), were initially made available to the public on January 27, 2021 via the online preprint server, bioRxiv.