Stability Indicating HPLC methods – part 1
When we are hired to develop a stability indicating method for our clients, what do we do?
The types of questions that need to be addressed depends on the stage of development that the method will be used for. First a few basic definitions.
What is a stability indicating method?
A stability indicating method is a quantitative test method that can detect possible degradants and impurities of drug substance (API) and drug products, normally using High Performance Liquid Chromatography (HPLC). Stability information is needed for regulatory submissions such as IND (Investigational New Drug Application) and NDA (New Drug Application) and to set expiration dates for the API or drug product. Stability indicating methods are also used to screen excipients when performing formulation development, in order to ensure that the possible excipients do not chemically react with the API.
Before performing stability studies, a stability indicating method is necessary so that any possible degradants generated during storage conditions (such as 5°C, 25°C/60%RH and 40°C/75%RH) can be separated, detected, and quantitated.
The method should meet several criteria based on the stage of development. Nominally, the method should be selective, sensitive, and provide precise and accurate results.
Sometimes Velesco is asked by a client to use a previously developed API method and determine whether it will work for the drug product. Other times, we develop full methods from scratch. Obviously time and money requirements are less when existing methods are used. However, sometimes a method isn’t fully appropriate for its new use and changes need to be made.
Stay tuned for further posts discussing the details of developing and validating a method. FDA guidances are helpful, but don’t provide the full and complete information that you may need to perform method development and validation.