Authenticating Drugs With Edible Microtags

The full version of this counterfeiting feature can be read in the July issue of our digital magazine: http://www.pharmtech.com/ptedigital0710

On-dose authentication, such as edible microtags, is a relatively new market that has been quietly developing but has the capability to provide new forms of anti-counterfeiting tools. The complexity of the pharmaceutical supply chain lends itself to entry points for adulterated or counterfeit products, which are often found in carefully counterfeited and high-quality packaging, or sometimes in authentic packaging that has either been stolen or used as a repacking operation. Most of the authentication formats in use today are packaging-oriented (e.g., printed codes, serial numbers, 1D and 2D barcodes, hologram stickers, etc.), but many of these are proving inadequate as international crime organisations become more sophisticated and more accustomed to the traditionally-used authentication technologies. As such, attention has now turned to on-dose technologies; for instance, ARmark Authentication Technologies and Colorcon have developed covert microtags, and Capsugel has licensed a technology that uses nanoembossing from NanoGuardian (a division of NanoInk).

Mike O'Neill

Last summer, the FDA issued draft guidance entitled "Incorporation of Physical-Chemical Identifiers (PCIDs) into Solid Oral Dosage Form Drug Products for Anti-Counterfeiting", which both validates industry interest in on-dose technologies and calls for the use of safe and well-studied food additives when using such technologies.

Specific design and location considerations should be met when selecting and incorporating PCIDs, and some labelling requirements in Europe stipulate the inclusion of a notice on the product indicating the use of PCIDs. In the case of the FDA, it is recommended to use permissible food additives, such as those generally recognised as safe (GRAS) or listed in the FDA Inactive Ingredient Guide (IIG). The preferred method for adding PCIDs is through a coating applied directly to a solid oral dosage form.

Edible microtags

Edible microtags made of silica, which has been safely used as an ingredient in food and drugs for decades at a limit of up to 2% by weight, can be applied in or on an individual unit dose to help identify, authenticate and ensure the quality of a medicinal product. Our TruTag microtags are made only of silica and added at a tiny fraction of the allowed limit. The tags contain tiny nanopores (voids) that produce a unique spectral signature, which can be chosen from more than one trillion possibilities. The signature can be read using a simple spectrometer-based reader. Line of sight is all that is required, meaning that tablets in a clear blister pack, for example, would not need to be removed from their packaging to be verified. Once the tags are visible to the reader, readout and verification is almost instantaneous. This spectrum can also be linked to (and verified by) other information printed on the package so that the medicine and packaging are authenticated together as part of an ePedigree track and trace system. Tampering with either the package or the contents in this scenario would flag a security violation.

Microtags can be created in random shapes and can be added to the outside of tablets via sprayable inks or coatings, or by using industry-standard pan coaters, without changing an existing process. Thanks to the maturity of the silicon wafer industry, silica microtags can be produced inexpensively using the electrochemical etch of a silicon wafer and then heating the silicon. This means microtags can be produced at a low cost, which is a key consideration for companies looking to deploy an anti-counterfeiting solution throughout their supply chains. Importantly, as no modifications to existing manufacturing processes or the product formulation are required, microtags can be added as a post-approval change to the tablet and would require only an annual report update.

The microtags can be applied both externally and internally, and can also be used simply as labels for quality assurance or other purposes. Applying the microtags to an outside coating means they can be read more directly than for applications that mix mictotags into ingredients. However, inside product application may be useful for forensic verification (e.g., liability cases or returns analysis).

We are currently trialling microtags with a nutraceutical company in the US, and have tested the technology in a variety of different applications with both clear and nominally opaque coatings. We are now in "four corner" testing to see how tagged tablets perform under accelerated shelf-life conditions by applying high heat and humidity. We are also in discussions with several pharmaceutical companies.

Novel technologies will be welcomed

While genuine pharmaceutical products are key to consumer health, they have been taken for granted for decades — part of an implicit trust that has been forged between the legitimate healthcare industry and their customer base. As the occurrence of counterfeiting is continuing to grow, the industry needs technologies that can help it to reduce such issues and maintain trust with consumers.

I believe that novel on-dose technologies will be welcomed by manufacturers because they can provide authentication confidence that can be used for quality assurance applications, returns monitoring, and anti-counterfeiting purposes. Consumers in particular should welcome new technologies that help ensure their health and safety, especially those that are based on well-studied and accepted materials. In the end, we all benefit from a more secure supply chain.

Mike O'Neill is Chief Technology Officer of TruTag Technologies.