West Pharmaceutical Services

Driven by the goal of bringing safe, effective treatment to patients and facilitated by the advancement in technology, the pharmaceutical industry is constantly evolving to meet the needs of the patients and the market. With this evolution, regulatory scrutiny over the safety and performance of injectable drug products also intensifies. 

While the main focus remains on the stability, efficiency, and safety of the drug products, the concept of “fit-for-purpose” is gaining traction. It emphasizes the need to holistically evaluate the overall drug system performance, including the packaging systems, for requirements such as functionality and compatibility with the intended use throughout shelf life and at the point of use. 

Imagine a drug product packaged within a glass prefilled syringe system. Fit-for-purpose principles demand that the glass barrel, elastomeric plunger, and needle shield do not introduce adverse reactions to the drug and perform optimally during drug administration. This means the plunger activates and glides smoothly, the glass barrel withstands pressure without breakage, and the entire system facilitates a comfortable and safe experience for the patient. 

Taking a holistic approach to biologics packaging  

The rapid growth of biologics demands a holistic approach to packaging. Unlike chemically synthesised drugs that have well-understood structures, biologics – derived from biological sources – are complex large molecules that are typically difficult to be fully characterized. As a result, it becomes a challenging task to predict and ensure their stability over time. Biologics are also particularly sensitive to heat and may easily react with contaminants, increasing the risk of degradation. This underscores the importance of finding packaging solutions capable of preserving the integrity of biologics, which may require storage at extremely low temperatures, going down to -80°C or even -180°C. 

"Taking a holistic approach to packaging systems is pivotal to meeting the increasingly unique requirements for the stability and performance of complex biologics in the pharma industry."

Laminated closures offer a synergistic solution to address the unique challenges of biologics packaging. These closures combine three key elements:

• Barrier films: Acting as a physical barrier between the closure's base elastomeric formulation and the drug, mitigating the risk of drug-closure interaction. Notably, the barrier film is usually made of a fluorocarbon-based polymer material, such as ethylene-tetrafluoroethylene (ETFE) or polytetrafluoroethylene (PTFE).

• Elastomeric formulations: Modern elastomeric formulations utilize better and more advanced raw materials with improved chemical cleanliness and reduced leachables. 

• Specialty coatings for lubricity: Applied to lower surface tackiness, thereby preventing stoppers from sticking together, reducing particle generation, and improving the machinability of the closures. Speciality lubricity coatings by itself, does not impart barrier properties. They may be used in combination with barrier film lamination to achieve the ideal solution for biologics applications. An example is Daikyo Seiko’s B2-coating technology, which is available from West and Daikyo. 

This synergy goes beyond individual components. The form and fit of the laminated closure with the complementary container (vial, syringe barrel or cartridge barrel) is also critical. While the film lamination plays a significant role as a barrier, the entire surface should not be covered by the film. The viscoelastic properties of the elastomeric formulation are still very much desired on the surface where the closure meets the container, as the flexibility and inherent stickiness of the elastomer allow a robust and integral seal to be formed at this interface. This is even more critical for syringe and cartridge systems as they rely solely on this seal at the plunger rib-barrel surface to achieve the container closure integrity for the backend of the syringe or cartridge. Therefore, the design and location of the film coverage are also key considerations when selecting a laminated closure. 

In conclusion, taking a holistic approach to packaging systems is pivotal to meeting the increasingly unique requirements for the stability and performance of complex biologics in the pharma industry. Well-designed laminated closures can bridge the gap, providing superior drug-closure compatibility and ensuring the quality and safety of the final drug product. For pharmaceutical manufacturers, this often begins with a commitment to understanding treatment complexities, regulatory requirements, and guidelines to design optimal packaging solutions. 

By embracing innovative packaging technologies, the industry can ensure the safe and effective delivery of biologics to patients, advancing healthcare outcomes and meeting evolving market demands.