Storage and Handling and the Pfizer mRNA COVID-19 Vaccine The vaccine uses messenger RNA, which is extremely fragile and requires very cold storage temperatures and can be damaged by light. This is the is the first ever messenger RNA vaccine to gain FDA clearance. Cartons of Pfizer-BioNTech COVID-19 Vaccine Multiple Dose Vials are shipped in thermal containers with dry ice. Once received, hospitals need to remove the vial cartons immediately from the thermal container and store in an ultra-low temperature freezer between -112ºF to -76ºF (-80ºC to -60ºC). Vials must be kept frozen and have minimized exposure to room light, and avoid exposure to direct sunlight and ultraviolet light.