As per regulatory requirements, each API, inactive ingredient, finished good, packing material and other related material shall be tested as per the specifications before use and prior to their release in the market for commercial use. But is it required to continue to perform all the tests before use on the material procured from the same source for years altogether?? Is it necessary to perform all the tests as per specifications on the finished goods being manufactured for years before their release into the market? The answer to this valid concern is the concept of periodic or skip testing.
In a pharmaceutical GMP plant, the testing of every batch of active, inactive, packaging material along with finished goods of not only time consuming, but is very expensive. This further enhances the cost of drugs and delays the availability of drugs to the patients.
Periodic or skip testing is the performance of specified tests at release on pre-selected batches and / or at predetermined intervals, rather than on a batch-to-batch basis. This is performed with the understanding that the untested batches must meet all acceptance criteria established for that product.
In case of active, inactive and packaging materials, only a few parameters tested at the finished good manufacturer site. For all the other parameters the manufacturer relies on vendor CoA. This process of reduced testing relies on qualification of the vendor and generation of substantial data w.r.t. the product meeting their predefined specifications consistently when sourced from the approved vendor. Intra-batch variations and quality history of the supplier shall be specifically assessed before taking decision for periodic or skip testing. It should also be noted that, vendor validation for periodic or skip testing is successful only if the material is coming directly from the manufacturers instead of traders.
The periodicity of the full testing shall be defined. Also, acceptable limits of difference between in-house generated analytical results and the results provided by supplier on its CoA should be defined.
This should be specifically noted that periodic or skip testing shall not be implied on identification test. Identification test of starting material is mandatory.
Similarly, in case of finished goods manufacturer, this concept may be applied. Example for skipping residual solvents and microbiological testing, for solid oral dosage forms. This reduced testing shall be fully justified and shall be implemented only after regulatory approval.
This should be noted that in case of any failure to meet acceptance criteria established for the periodic or skip test, the same shall be immediately notified to the regulatory authority(ies). Decision for restoring to the normal detailed testing may be taken as per the requirement.
This should be well understood that the quality, safety and efficacy of drug products is the prime responsibility of the formulation manufacturer. Automatically, the responsibility of the quality of raw material used to manufacture drug products also lies with him. Hence, one should be absolutely sure about the quality of raw materials used and finished product produced before the drug is released into the market. Accordingly, the decision of periodic or skip testing shall be implemented.