US FDA has issued guidelines to  pharmaceutical manufacturers who want to use physical  chemical identifiers (PCIDs) in their solid oral dosage forms to prevent or reduce the potential for counterfeiting.

The use of PCIDs  is to identify and authenticate a drug product or a solid oral dosage form (SOFD). Although the proclaimed statistics related to counterfeit drugs by WHO appear to be unsubstantiated, it appears that the industry is experiencing an increase in the number of counterfeit drugs that are entering into supply chain.  Therefore, ensuring the integrity of the supply chain is paramount to ensuring that patients get the proper drug in the proper dosage form, tested to conformance with stringent specifications, according to the international drug regulatory.

This guidance provides recommendations to pharmaceutical manufacturers on the  design considerations to incorporate PCIDS into SODFs. For this,supporting documentation is  to be submitted in new drug applications (NDAs) and abbreviated new drug applications (ANDAs) to address the proposed incorporation of PCIDs in SODFs. More over the documentation is  to be submitted in post-approval submissions to report approval to include PCIDs into SODFs.

Design considerations for incorporation of PCIDS in solid oral dosage forms  include  pharmacological and toxicological considerations.

The incorporation of components used in radiofrequency identification for drug products is outside the scope of this guidance. In addition, the  guidance does not apply to manufacturing or formulation changes, made in conjunction with the addition of a PCID. But it goes merely inserting the PCID into a blending or mixing operation. For instance adding a PCID to a non-functional tablet film coating is covered by this guidance, But adding a non-functional film coating that contains a PCID to a previously uncoated tablet involves manufacturing changes that are not covered under  this guidance. The incorporation of a PCID into the packaging or labelling is not covered in this guidance.

Pharmaceutical manufacturers aiming to thwart drug product counterfeiting have been investigating readily available technologies that may make drug products more difficult to duplicate. One approach involves adding a trace amount of an inactive ingredient to an existing  dosage form. A unique physical-chemical characteristic of that ingredient makes it possible to detect and authenticate legitimate dosage forms, and to identify counterfeits, according to the guidelines.

There are various available means for presentation and detection of PCIDs . These include photolithography, holography, optical microscopy, laser scanning devices and excitation/fluorescence detection. Some identifying characteristics, such as pigments or flavours, could be easily observed by patients, healthcare practitioners, and pharmacies. Others could require the use of a detection instrument like  a scanner, photometric detector and  mass spectrometry.

FDA anticipates that many of the ingredients that will ultimately be employed as PCIDs are already used as food additives, colourants, or excipients with established safety profiles.