Executives from Moderna and Pfizer, two leading mRNA based vaccine developer have separately intimated Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practice in the USA about extreme conditions required to store their potential COVID-19 vaccines.
Moderna updated the authorities that its coronavirus vaccine candidate mRNA-1273 would require a storage temperature of negative 4 degrees Fahrenheit (negative 20 degrees). While BioNTech and Pfizer’s candidates, BN1162b2 and BNT162b2, need to be stored in negative 94 degrees Fahrenheit (negative 70 degrees).
Pfizer will need to use ultralow temperature freezers and thermal shipper storage for its COVID-19 vaccine candidates.
The requirement of stringent standards for refrigeration may hamper how these vaccines are distributed to the billions expecting to receive them once they receive regulatory clearances.
These storage conditions would make the traditional office or pharmacy-based vaccination very difficult as only tertiary hospitals and laboratories would be able to maintain the required conditions. It would be impossible to administer the vaccine at community clinics and local pharmacies as they will not have the required equipment for the same.
On such an occasion, vaccines would have to given in intensive one-day vaccination drives allowing only a fraction of the global population to receive the vaccine.
The stringent storage conditions resulting in difficulties of storing and shipping mRNA COVID-19 vaccines to hundreds of millions of people put both Moderna and BioNTech-Pfizer vaccines at a competitive disadvantage as other types of vaccines require less intense rules around storage.
There are about six COVID-19 vaccine candidates in clinical trials in the U.S. However, not all of them are mRNA vaccines. While the vaccine being developed by AstraZeneca and the University of Oxford is a recombinant viral vector vaccine, Inovio Pharmaceutical Inc.’s candidate is DNA-based.