Packaging stress testing

Stress testing is an important tool for the prediction of stability-related problems. The results of stress testing can be useful to many areas of pharmaceutical research and development beyond the obvious areas of analytical, formulation, and packaging development. Well-designed stress-test-... 

In the case of more than 1 manufacturing country or multiple packaging materials and shapes, it is acceptable to submit only the data of longterm and stress testing on the new drug manufactured in 1 country, and confirm and preserve the results of an accelerated testing on new products manufactured in different countries. 

At the early stages of optimisation, preformulation studies are usually conducted to screen excipients or packaging materials and to select those compatible with the candidate drug, using accelerated stress testing procedures. More details about the preformulation techniques, which can be employed for compatibility studies, are discussed in Chapter 3. The importance of doing compatibility studies is for reducing the number of excipients and formulation options to test in further product optimisation studies. 

At the end of the wafer processing, the wafer with the IC devices is inspected for defects and reviewed with relevant metrology. If the defect level is acceptable, the IC wafer is sent to the testing facility, where it is electrically probed to check for electrical performance. Next, the IC wafer is stress tested, which involves operating it at the extremes of its specified typical use conditions. If the IC wafer passes the functional and stress tests, it is sent to the packaging facility, where bond pad... 

Internal factors like the reactivity of active ingredient(s), excipients, and packaging material, as well as the interactions between these components. The risks are reduced by stress testing as part of drug substance and product development. 

External factors like heat and moisture, light, pH, oxygen. The risks are reduced by long-term, accelerated and stress testing, to identify the adequate packaging material, shelf-life and storage recommendations on labels. 

To cover extremely hot and dry conditions, additional stress tests conducted on one batch for up to 3 months at 50°C/ambient humidity may be helpful to select the appropriate packaging material during product development. 

Once this data is generated, it can be used in typical acceleration factor models relating accelerated stress tests to field data. For example, if it is determined that it takes x hours or cycles for an assembled package to fail in a laboratory test, the acceleration factor model can be used to extrapolate expected life of the device in typical field operating conditions. Details on acceleration factor models and sample calculations are provided in the next chapter. 

Method specificity stress testing of drug substances/product types under several conditions should be performed to support the suitability of the method. Depending on the matrix and packaging, these include extremes of pH, heat, exposure to oxidation, hiunidity, and light. In the case of drug substances, heat... 

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