TABLE OF CONTENTS Systems that are operational in regulated environments but are not validated must be brought under control. This is termed as retrospective validation. Retrospective validation costs must be balanced against the cost of a replacement system as this is the most expensive way to validate a system.
The best regulatory advice for retrospective validation comes from the PIC/S guidance document31 where Chapter 16 is devoted to the subject; selected quotations are presented here, however the reader is strongly advised to read the whole section if faced with a retrospective validation of a CDS.
Section 16.1: Retrospective validation is not equivalent to prospective validation and is not an option for new systems. Firms will be required to justify the continued use of existing computerised systems that have been inadequately documented for validation purposes. Some of this may be based on historical evidence but much will be concerned with re-defining, documenting, re-qualifying, prospectively validating applications and introducing GXP related life-cycle controls
Section 16.2: A significant number of legacy systems may operate satisfactorily and reliably, however, this does not preclude them from a requirement for validation. The approach to be taken is to provide data and information to support the retrospective documentation of the system to provide validation and re-qualification evidence
Section 16.4: Nevertheless, the validation strategy would be consistent with the principles established for classic retrospective validation where the assurances are established, based on compilation and formal review of the history of...
