Storage Stress testing

Storage conditions will be used. Standard conditions to simulate normal storage are temperatures of 25 or 30 °C and relative humidity of 60 or 65%. A minimum of 12 months real-time data is required for a marketing authorisation application. Real-time data should be supported by accelerated and intermediate stress testing at higher temperature/relative humidity. Photostability should be verified using a single batch. 

Long term storage stability tests of flavor beta-cyclodextrin complexes under "non-stress" conditions at room temperature showed that molecular encapsulation in most cases provided an almost perfect preservation of flavors upon ten years storage. The degree of preserving power of cyclodextrin complexation is expressed using a comparison of total flavor content of complexed flavor samples deteimined in 1977 and 1987,respectively./Table IV./... 

Stress testing is used to determine the intrinsic physical and chemical stability of the pharmaceutical ingredient under accelerated, elevated temperature storage conditions, such as 50°C- 75% RH, 40°C- 75% RH, and 30°C- 60% RH. 

An important aspect of this definition is that the studies are part of the formal, definitive, storage program. In contrast, ICH, in Annex 1, Glossary and Information of the revised stability guideline (6) defined stress testing (drug substance) as ... 

Figure 13 X-ray powder diffractograms of methylprednisolone sodium succinate in mannitol during stress testing at 40°C, showing crystallization of mannitol during storage (A) initial freeze-dried powder (B) two months and (C) six months.

---