What you need to know about BioNTech — the European company behind Pfizer's Covid-19 vaccine

Pfizer says its coronavirus vaccine — developed in partnership with BioNTech — was more than 90% effective in preventing Covid-19 infection. The news was hailed as a significant milestone in the race to deliver a vaccine that can help bring an end to the coronavirus pandemic. There are still huge challenges ahead for the development of a vaccine, but as hopes rise worldwide, CNBC takes a look at BioNTech’s history.