Storage temperatures for COVID-19 vaccines

During the development and characterization phase of the vaccines, manufacturers perform different stability studies that include an evaluation of the appropriate storage conditions, in order to establish the vaccine’s shelf life. Accelerated stability studies are also carried out to determine other storage conditions, and the maximum time of exposure to these temperatures (1). 

This information allows the regulatory authorities, in the event of variations in the storage temperature or a break in the cold chain, to determine whether the vaccine can be used (considering alternative storage temperatures, when applicable) or whether it should be discarded. 

In the case of COVID-19 vaccines, each vaccine has different storage specifications. In the following table, summarizing the storage conditions for these vaccines, it can be seen that some have alternative storage temperatures applicable for a given period of time. 

When storing a vaccine at the alternative storage temperature, where applicable, the new shelf life must be recalculated and recorded on the vaccine vial, taking into account the date on which storage at that temperature began; for example, five days for the Pfizer Tozinameran vaccine, from the moment the vaccine is kept between 2^oC and 8 ^oC (36^oF to 46^oF).

Prepared by the authors based on published data on vaccines.  Source: (1) WHO. Stability evaluation of vaccines. Can be found at; https://www.who.int/biologicals/areas/vaccines/stability/en/

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