Retrospective Validation, a great deal of controversy exists about this subject; however do not be backed into a corner by over zealous consultants. There are many reasons that can give good cause to retrospectively qualify a facility (or any piece of equipment that would normally be validated).
Some of the reasons we have encountered are listed below. This is in no way meant to be a definitive list;
In most cases it is necessary to start with a validation plan, in which the scope, the action being taken and the responsibilities can be detailed. From then on use the standard layout for your
IQ's and
OQ's. When the IQ and OQ are completed and the P1Q, and where required, P2Q, ensure that use an abundance of production data, produce and review plenty of it. However if the existing production data shows that the process is not consistently producing in accordance with the process specification, then you must sort out the process first. Review the whole process and ascertain where and what is causing the inconsistencies to occur. Validation is not an exercise to get the process right. You validate once your process is consistently producing product to the expected specification. Once you are certain of this, then start your validation procedure.
Do not forget that validation is all about documented evidence. If this is a retrospective validation you will have records of the
performance of the subject equipment, use them fully. Use your
Validation Risk Assessment to define the validation scope and raise your protocols accordingly.
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RETROSPECTIVE VALIDATION SCOPE.
Use your
Risk Impact Assessment to define the validation scope and raise your protocols accordingly.
If this system has never been validated, then you have no alternative, you must raise the full
Installation Qualification (IQ),
Operational Qualification (OQ),
Performance Qualification PQ and perhaps
Design Qualification DQ, get them approved and then execute them.
If this system is being re-validated because of discrepancies with the original validation. Then you should raise a Supplementary IQ and OQ, or in an instance where the system is small or very simple, a combines
IQ, OQ. In the supplementary protocol you can review the existing validated status and list additional tests / inspection as you think necessary.
Think well before going down this road, it does highlight to a regulator all the things that were missed in the original validation exercise. The paperwork trail can become messy between original protocols and supplementary protocols. It is often best to declare that a validation review (for any of the listed reasons) is to be carried out. On the bases of the review outcome, revalidate equipment as required. Keeping the paperwork nice and simple.
RETROSPECTIVE VALIDATION.
