GMP Requirements for the Validation of Excel Spreadsheets - 19 Nov 2014
Excel Spreadsheets are commonly used, and in various departments within the pharmaceutical companies. They are easy to use, and enable macros that allow making calculations in a very convenient way. These advantages also present a significant risk. In the pharmaceutical environment, such computerized systems as spreadsheets need to be validated and also comply with a number of requirements. However, controls are quite often inadequate and thus result in a compliance risk.
The regulatory agencies provide some guidance on the validation requirements of spreadsheets. A Q&A issued by European Medicines Agency provides the following guidance: "Validation according to paragraph 4 of annex 11 is required at least for spreadsheets that contain custom code (e.g. Visual Basic for applications). Formulas or other types of algorithm should be verified for correctness. " Therefore, appropriate controls for templates of spreadsheets must be in place. Erroneous calculations due to data remaining from previous calculations must be avoided. The templates should also be suitably checked for accuracy and reliability (annex 11 p7.1) and should be stored in a manner which ensures appropriate version control (chapter 4 p4.1).
When it comes to accuracy checks (as required in Annex 11 p 6), data integrity is an important issue. The Q&A document explains that both the files and the calculations should be secured in such a way that formulations are not accidentally overwritten. Accidental input of an inappropriate data type should be prevented or result in an error message.