Coding technologies: breaking down the barriers

Dipankar Dey. Head of Process and Validation at OYSTAR Manesty.Tablet coding or identification is based either on the detection system being overt (visual to the naked eye) or covert (non-visual). The coding of tablets is obvious at an overt level because of size, shape, colour and logo design. These attributes are a function of the manufacturing process, such as the punch and die used to compress the tablet and, where appropriate, the coating material. More recently, holograms and bar codes have also been used, but the challenge with any overt technology is that it may be copied by any counterfeiter with access to a tablet press or coater.

Some covert coding functions have existed for a while; for example, taste or smell have helped track counterfeit medicines before, but this is purely by luck and the observation of a patient, doctor or nurse. More recently, covert coding technologies have been introduced in the manufacture of certain tablets. These can be divided into invasive technologies, which include chemical or physical markers that are applied to the tablet or tablet coat, and non‑invasive technologies based on lasers, which create codes on each individual tablet without adding to the tablet composition itself.

The pharmaceutical industry is taking the issue of protection and anti-counterfeiting very seriously. Packaging and supply chain security based on RFID barcodes is well established already, but progress in counterfeit packaging has also prompted manufacturers to introduce on dose technologies.

All the top pharmaceutical manufacturers have introduced, or are planning to introduce, anti‑counterfeiting solutions to protect brand identity, which is a serious business need. In addition to compromising patient safety, counterfeit medicines lead to loss of market share and revenues, legal liability issues and loss of reputation.

Unfortunately, there are barriers hindering the uptake of coding technologies. The production and distribution of tablets is complex, and when an extra material is added to a tablet it creates regulatory uncertainty that necessitates the submission of extra safety data. In this regard, the FDA Guideline to the Incorporation of Physical‑Chemical Identifiers into Solid Oral Dosage Form Drug Products for Anti counterfeiting has been a major step forward (July 2009) because it will at least encourage pharmaceutical manufacturers to evaluate anti-counterfeiting technologies.

Cost is also an issue, especially where production efficiency may be compromised by the addition of an extra step to incorporate a code. Although big pharmaceutical companies are pursuing anti‑counterfeiting technologies regardless, it is uncertain whether the same can be said for generics manufacturers given the greater cost pressures on generic products. This situation is a time bomb that will only be resolved by a major incident unless action is mandated — regulatory authorities should recommend all companies to actively pursue an anti‑counterfeit policy and should audit on this point.

Future solutions

The market for nanotechnology-based anti-counterfeiting solutions is estimated at $440 million, and comprises applications in high-value documents, pharmaceuticals, fuel and luxury goods. Scientifically and technically, however, nanotechnology is still in its infancy. Commercial applications of nanotechnology in coding tablets are coming to the market gradually, but its usefulness for authentication and track and trace applications started only around 4 years ago. With the exception of tracer markers in inks and paints on packaging, most applications for nanotechnology in the anti‑counterfeiting field are still in the laboratory stage — particularly for tablet coding. However, our research indicates that commercial applications will be forthcoming as regulatory and technical barriers are overcome.

As the greatest risk lies with the patient, it is authentication by the patient that must be achieved. This can be envisaged as the ultimate in dispensing where the link between prescription, tablet manufacture and the patient is established. Innovations in mobile technology and tablet serialisation should make this vision feasible; for instance, solutions currently in development offer verification of the tablet by the patient using a mobile telephone. This type of verification will also be needed with the growth of personalised medicines where a particular tablet will be made for a particular patient. If the site of manufacture is remote to the patient then verification that the tablet contains the unique formulation will be needed.