Vision System Helps Ensure Pharmaceutical Supply Chain Safety

To meet increasingly stringent automatic identification requirements, this pharmaceutical packager turned to camera-based code scanners to ensure correct packaging.

Despite efforts, counterfeit drugs continue to be intermingled with the legitimate drug supply. The World Health Organization estimates that up to 30 percent of prescription drugs in developing countries are counterfeit, and in developed countries, counterfeit drugs make up as much as 1 percent of the market. Congress passed the Prescription Drug Marketing Act (PDMA) in 1987, creating a chain of custody tracking requirements for distributors of prescription drugs and related products. Enforcement of these requirements rests with the U.S. Food and Drug Administration (FDA).

This requirement has become known as an electronic pedigree or e-pedigree: a statement of origin that identifies each prior sale, purchase or trade of a drug. The FDA is expected to eventually follow the e-pedigree specifications set by GS1, a leading global organization dedicated to the design and implementation of global standards and solutions to improve the efficiency and visibility of supply and demand chains globally and across sectors. The GS1 Healthcare automatic identification standard includes a Global Trade Item Number (GTIN), Global Location Number (GLN) and Global Data Synchronization Number (GDSN). The GS1 Healthcare User Group recommends “investing in camera-based code scanners to address specific needs for automatic identification in healthcare.”

“The primary goal of FDA standards and e-pedigree laws are to protect consumers from contaminated medicine and counterfeit drugs,” says John Scholes, special projects manager, Omega Design Corp., a packaging machinery manufacturer in Exton, Pa. “To do this, we must keep track of products along the supply chain down to the unit or container level. Although compliance dates and final standards are constantly changing and vary per state, the pharmaceutical industry widely accepts that the definitive requirement will involve serialization. We found that what we implemented at our facility is a cost-effective, easy-to-implement method of incorporating 2D data matrix serialization within new and existing packaging lines without compromising machine speeds or accuracy.”

While the pharmaceutical industry is considering several methods to comply with these upcoming requirements, all track-and-trace programs assign each container a unique serialized label that stays with it throughout its use. Soon after it is filled, the container becomes part of a series of larger packaging—usually bundles, boxes and pallets. Each package must be linked in a parent-child relationship.

Most pharmaceutical companies use radio frequency identification (RFID) tags for higher levels of packaging such as pallets and boxes. However, the use of RFID tags at the container and bundle level increases packaging costs.

Another concern is the high cost of the RFID interrogators pharmacists must use to verify the pedigree of the container used for each prescription. In comparison, printing a digital code on a paper label has the advantage of much lower costs for both the label and the reader, high print and apply speeds, negligible failure rates and easy implementation.

Knowing bundle contents

In a typical pharmaceutical manufacturing line, several packaging processes, such as unscrambling, desiccant insertion, filling, cottoning, sealing and capping, may occur before a container finally receives its serialized label or RFID tag. Therefore, packagers must confirm, and not assume, that a container belongs on the packaging line before a serialized label is affixed to the side of a container. Even after receiving its label, the way in which containers flow through other processes can compromise the downstream effort to link higher-level aggregate codes with individual units.

To create a bundle, containers must flow through a shrink-bundling system that collates, wraps and unitizes the containers. A single misplaced or rejected container, extracted after its place in the sequence had been established, might corrupt the integrity of every subsequent bundle.

The only way to guarantee the contents of a bundle is to first establish a bundle’s integrity and then identify its containers. But side labels pose a challenge for packagers trying to identify containers after a bundle has been created. For instance, how do you scan the codes on the middle containers in a 3x4 bundle, since the labels are blocked from all sides? Omega Design’s answer is to print a unique ID on the bottom of every empty container to complement—not replace—the serialized label affixed to the side of the container.

The side label is referenced throughout the life of the container, providing the unique container ID as well as all of the relevant consumer information such as product identity, manufacturer, dosage, quantity and other information. The unique bottom code enables the packager to easily identify containers after they’ve been aggregated within a bundle. When a bundle is created, the serialized side labels would be difficult to see, but the unique ID on the bottom of the container is visible through the transparent shrinkwrap film.

Omega Design implements this track-and-trace approach with a single unscrambler that can maintain full control over each container—its speed, height and orientation—while passing under the print head and over the verification and rejection stations. The unscrambler accepts bulk bottles and orients them sequentially on the production line. It prints and verifies a unique ID on the bottom of every empty container. This unique ID contains enough information to keep track of the container temporarily on the packaging line.

Once a larger, permanent and fully serialized label is applied to the container, a camera and serialized software management system put the label code and bottom code in sync. When it’s time for final packaging, the shrink bundler groups and wraps the specified number of containers into a bundle. A robot lifts each bundle and passes it over another ID reader that identifies the containers in the bundle. A new label is then placed on the bundle that is linked to each package in the bundle. A parent-child relationship is developed.

Demanding application

The ID reader used on the unscrambler must accurately read Data Matrix codes while keeping up with a line that runs at 50 to 300 bottles per minute. The bundler provides an even more challenging application because the ID reader must read all of the bottles in the bundle with one image. “We picked Cognex 5000 Series vision systems for this application because our experience shows that they provide the required accuracy for reading 2D Data Matrix codes,” said Scholes.

In-Sight vision systems incorporate Cognex IDMax Data Matrix code reading software, based on PatMax technology, to handle a range of degradations to the appearance of the code and provide robust and reliable decoding under all conditions. Omega Design uses the In-Sight 5410 ID reader on the unscrambler and the higher performance In-Sight 5603 on the bundler application. Cognex also provides a full line of fixed and handheld ID readers that can be used to verify the origin of the bottle at any point in the supply chain.

Shaun Keperling, of Omega Design, used Cognex’s spreadsheet-based programming interface to overlay images of the 12 inspected codes, provide pass/fail indications for each code, and also provide a pass/fail for the entire bundle on the user interface. “The spreadsheet interface is flexible,” Keperling said.

The program kicks off when the vision system receives a digital signal from the programmable logic controller (PLC) that a bundle is in position for inspection. The program first captures the image of the bottom of the bundle containing a dozen 2D codes. Then, 12 different inspection tools are run to read the codes. If all of the codes are read, then a digital output is sent back to the PLC. The PLC instructs the robot to place the bundle on the pass conveyor. The vision system uploads the container IDs to a computer where they are managed by track-and-trace software. If the inspection fails, the controlling PLC instructs the robot to reposition the bundle two more times and re-triggers the inspection. If these inspections also fail, then the bundle is channeled to a reject chute.

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