The structure of the functional specification is shown in Figure 3. Each document had its own number and revision history so that some parts of the specification could be reviewed and approved before other parts were complete. Basing the structure on the control levels defined within the S88 model results in the minimum of interaction between the documents, allowing parallel document development to be practical.
Our approach has been to make use of the work normally performed by the supplier to reduce the work that would otherwise be done on site. By simply ensuring that all test records are kept in a form that provides documented evidence that the system satisfies the requirements within the URS, we have added very little work for the supplier and opened up the opportunity for significant savings during the validation process. On one control system for an API manufacturing plant it was estimated that 11 weeks were removed from the site activities as a result of adopting this approach.
The validation master plan (VMP), IQ, OQ and PQ protocols still need to be produced, but parts of the IQ protocol and most of the OQ protocol can now be little more than lists that reference the test records from the FAT and SAT. It is often said that software does not break, it is already broken! The corollary to this is that the functionality provided by the software will not change when the system is installed on site unless the environment in which the software application is running changes; a simple justification for not repeating the tests.
The approach described in this article has been used on a number of pharmaceutical control system projects. Most of the purchasers have embraced the concept, including their validation staff, from the start. One major operating company actually provides document templates to their supplier so that all the documentation fits seamlessly into their document system. However, some have not had the courage to change their existing practice and so have missed the opportunity to reduce costs and get their products to market earlier.
1. S. Haisman and P. So, "Factory Acceptance Testing", Proceedings of the ISPE 2000 Annual Meeting, San Diego, CA, USA (2000).
2. ISPE Gamp 4, GAMP Guide for Validation of Automated Systems, ISPE (Tampa, FL, USA, 2001).