Exposure of BCG and measles vaccines to sub-zero temperatures

Dear sirs,

In the specific case of the Serum Institute laboratory, the package insert states that it is recommended to store the vaccines in the dark, between 2°C and 8°C. For long-term storage, a temperature of -20°C is recommended for the freeze-dried vaccine. The diluent should not be frozen, but kept cool.
The question arises because these BCG and measles vaccines, in combination with rubella and mumps-rubella, arrive at a MKT of around -3°C; that is, they don't reach -20°C, but neither do they reach the 2°C to 8°C range. We store them refrigerated and continue to do so until administration, but I don't know if they can be frozen at -20°C after having been stored between 2°C and 8°C.

 Best regards.

Dear Sirs, 

Thank you all for answering my queries about storing BCG and Measles vaccines at sub-zero temperature.

With regards,

Tshewang Tamang

Yes. Both vaccines can kept at minus temperature. Even after reconstitution both vaccines should kept near the ice pack or within the hole of the ice pack. In my observation the foam pad can't keep the vaccines at desired temperature.

Dear Tshewang,

Typically the manufacturers or the Marketing Authorization Holders (MAHs) perform a freeze-thaw study for their product to map possible quality failures. I highly recommend adressing your question towards the MAH. There are several issues that can raise if water based vaccine is frozen leading to visible/subvisible particles and failure against the quality specifications. The MAH should support you to make the decision if the considered batches can still be used or not.    

Freeze dried products do not contain water (or contains very little) which often allows MAH to claim stability below zero Celcius temperature for longer shelf-lifes. 

All the best,

Eero