Stability Testing

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Stability testing is an important part of the pharmaceutical drug development process by helping to uncover the safety, integrity, shelf life, and storage conditions of the drug. This testing determines how the quality of the drug product or drug substance, varies with time under the influence of environmental factors such as temperature, humidity, and light. This assessment determines whether any physical, chemical or microbiological changes affect the efficiency and integrity of the final drug product.  Through stability testing, one can establish a proper stability condition for the formulation and pharmaceutical product.

The materials that are subject to stability are the active pharmaceutical ingredient (API) and the finished pharmaceutical product. Usually, stability testing occurs during preformulation, final formulation, or post-marketing.  The International Conference of Harmonization (ICH) guidelines Q1A specify the standards that should be followed for conductivity stability studies and the data which must be collected for a new drug substance or drug product. 

Drug Substance and Drug Products are typically studied under at least two different storage conditions - long-term ambient storage and accelerated conditions. Preferably, the same container closure system and packaging materials that are intended for the final product are used. Typically, an informal study is conducted before a formal stability study of three validation batches of the product. 

 As a fully Good Manufacturing Practice (cGMP) compliant laboratory, ChRi follows ICH guidelines for stability testing and storage conditions of pharmaceutical products. ChRi Laboratories provides expertise in developing robust stability studies to help access the quality, safety, and efficacy. Our testing follows the ICH guidelines by covering the physical, chemical, and microbiological attributes for new drug substances and finished drug products. Some of these stability components include:    

• Physical: Appearance, melting point, water content, clarity and color of the solution, pH, dissolution and disintegration characteristics, viscosity, crystal modification or particle size 
• Chemical: Assay, degradation products, related substances, and residual solvents 
• Microbial: Growth in microorganisms and efficiency of preservative contents such as antioxidants and antimicrobial preservatives

ChRi recommends that the frequency of test points for long-term studies should be sufficient to establish the stability profile for a given period. Recommended test frequency for intermediate storage condition is a minimum of four time points, including the initial and final time points, for a 12-month study. For accelerated storage conditions, the test frequency is recommended to be a minimum of three-time points, including the initial and final time points for a 6-month study.