The USP has published a so called stimuli article which is intended to provide a proposal to revise an existing USP monograph. The article provides a brief overview of drug product stability studies and practices with focus on temperature control during storage and distribution. The authors state that "recent stability studies support redefining controlled room temperature (CRT) by broadening the permitted range when appropriate for specific products. Currently marketed CRT products are not labeled to conform to a standard storage temperature range, as it is the case with cold chain products. CRT ranges on product labels can vary, even within an organization, and can differ from the USP definition."
The article concludes that stability studies historically support product storage in a relatively narrow range such as 20-25 or 15-25. Current studies support the approach to revise the current requirements and to allow store between 2 and 30 degree Celsius. Such a change would have to be incorporated into USP general chapter "Packaging and Storage Requirements <659>. In addition, the authors propose "that both the primary packaging and the case labels list both the storage conditions (and distribution conditions if different) and typical excursion temperature data, e.g., store below 30, excursion to 40 for 1 month".
Please find the stimuli article in the Pharmacopeial Forum (PF). In order to read and download the article you need to register at no costs for the PF.