Which vaccine is the fastest new vaccine ever developed and authorized at scale?

The first COVID-19 vaccines to receive emergency use authorization, such as Pfizer-BioNTech’s mRNA vaccine, did so in December 2020 after roughly a year of development. That was far faster than the usual many-year vaccine timeline. Scientists were able to move quickly because the platform built on decades of basic research in mRNA technology and because the virus’s genetic sequence was shared early in 2020. The record speed did not mean shortcuts in safety monitoring, which continued through large clinical trials and post-authorization surveillance.