The selection of the suitable climatic zone is made according to the guidelines of the International Conference on Harmonization of Technical Requirements of Pharmaceuticals for Human Use Guidelines Q1A(R2) "Stability testing of new drug substances and products" and ICH Q1F "Stability data Package for Registration in Climatic Zones III and IV". Climatic Zones I and II are relevant for registrations in Europe, USA and Japan. For Brazil, for example, stability data must be determined in climate zone IVb. The WHO Stability Guideline covers the requirements for all climate zones. Annex 2, Table 2 of the Guideline describes about 200 countries with their country-specific climatic conditions. Companies must take these into account for long-term storage when approving their products.

The WHO guideline describes the following climate zones:

• Zone I: "temperatures" 21°C/45% RH (relative humidity)
• Zone II: "subtropical" 25°C/60% RH
• Zone III: "hot/dry" 30°C/35% RH
• Zone IVa: "hot/humid" 30°C/65% RH
• Zone IVb: "hot/very humid" 30°C/75% RH

The ICH-Guideline combines climate zones I and II into one and defines them via the worst case condition, i.e. 25°C/60% RH.

Similarly, climate zones III, IVa and IVb can be combined into a worst case condition with 30°C/75% RH. In addition to these two long-term stability programs, we also offer accelerated studies at 40°C/75% RH.

DSI-pharm supports you with the approval of your product. Together, we plan your stability study and support you with analytical expertise using our many years of experience until your product is launched and beyond, in on-going stability studies!