In December 2020, Pfizer and BioNTech's BNT162b2 COVID-19 vaccine became the first-ever mRNA-based vaccine to be approved by the FDA. To add to its uniqueness, the vaccine became one of the only to require a temperature below -50°C all along the cold chain terrain to ensure its stability, efficacy and safety. However, that is not the case any longer. Let’s take a look at how things have changed and other common temperatures along the cold chain for COVID-19 vaccines.