For retrospective validation can we take those batches which is already in concurrent validation?
Please note that Retrospective validation is not acceptable to the regulatory authorities unless there is specific iustified reason to do so. Therefore, please consider prospective or concurrent process validation of the products.
in such case prospective validation is recommended.
Prospective validation is establishing documented evidence that a process, procedure, system,
equipment or mechanism used in manufacture does what it purports to do based on a pre-planned validation protocol. Therefore, unless process validation is complete, the validation batches individually should not be released and sold.
In most cases, the Process validation needs to be completed successfully and a high degree of assurance in the process achieved before commercial distribution of a product. (Prospective validation)
Concurrent validation should be carried out during routine production of products intended for sale in exceptional circumstances when data from replicate production runs are unavailable because only a limited number of batches have been produced, batches are produced infrequently or batches are produced by a validated process that has been modified. Individual batches may be evaluated and released before completion of the validation exercise, based on
thorough monitoring and testing of the batches.
In special situations, the Process validation can be designed to release validation batch for distribution before complete execution of the protocol steps and activities, i.e., concurrent release. FDA expects that concurrent release will be used rarely.