On Jan. 8, 2021, Pfizer and BioNTech announced results from an in vitro study conducted by Pfizer and the University of Texas Medical Branch that showed the antibodies from people who have received the Pfizer-BioNTech COVID-19 vaccine effectively neutralize SARS-CoV-2 with a key mutation that is also found in two highly transmissible strains. The results were published on the preprint server bioRxiv.