Guidelines on the stability evaluation of vaccines for use under extended controlled temperature conditions, Annex 5, TRS No 999

Vaccines are complex biological products and may undergo degradation during long-term storage under cold chain conditions (for example, 2–8 °C) and this is typically enhanced at higher temperatures. Consequently, establishing the stability characteristics of products is a critical element of the overall evaluation by a national regulatory authority (NRA) to ensure that licensed vaccines remain efficacious at the end of their shelf-life when stored under the approved conditions. In response to the stability assessment needs identified by NRAs, WHO developed guidelines on the stability evaluation of vaccines to assist its Member States.