Plus, because of its early study in youngsters, it could follow up with an approval in children a year ahead of Pfizer's. RELATED: Pfizer's 'Prevnar 20' gets in FDA fast lane as next-gen pneumococcal vaccine race heats up with Merck Tuesday's Pfizer approval comes on top of its raging success with Comirnaty, its BioNTech-partnered COVID-19 vaccine. While competing COVID shots have struggled with safety concerns and supply issues, Pfizer and BioNTech have become the world's most reliable and prolific supplier of coronavirus vaccines.