Glass or Plastic—A Question of Use

Packaging plays an important role in preserving the stability and quality of pharmaceutical products so that they are safe and effective when patients use them. Selecting the right type of packaging material to use is, therefore, crucial, especially if it is in direct contact with the product. The packaging must not have an adverse effect on the product, but it is also equally important to ensure that the product does not change the properties of the packaging and affect its protective function. Glass and plastic are well established primary packaging materials for the pharmaceutical industry but they both have their advantages and disadvantages. 

Many medicines do well when packaged in both glass and plastic, observes Jens Heymann, senior vice-president, Europe & Asia Tubular Glass, Gerresheimer. “How well glass or plastic tolerates an active ingredient depends on its composition. Drugs must be carefully examined at an early stage, ideally when clinical tests with the primary packaging begin. The pharmacist must ensure that all possible interactions between the contents and the packaging are recorded and assessed for risk,” he explains. 

“Depending on the field of application, the pharmaceutical company may decide to use type I, type II, or type III glass, based on the hydrolytic resistance required,” says Heymann, highlighting that Gerresheimer’s range extends from cough syrup bottles made from amber glass to sterile ready-to-fill (RTF) vials made from tubular glass designed for special injectables. “We constantly adapt our production processes to meet increasingly stringent market requirements,” he adds. Gerresheimer’s Gx Elite Vials, for example, are produced using a conversion process that has been optimized to design out the risk of flaws during production (1). Heymann explains that all glass-to-glass or glass-to-metal contact is removed, beginning from tubular glass right through to the final packaging. The Gx Elite Vials have better quality as a result. The highly shatter-resistant vials are durable and free of cosmetic defects. They have a robust structure and their resistance to delamination protects the drug inside (1).

Gerresheimer also has expertise in making glass syringes. In January 2017, Gerresheimer announced the introduction of a new metal-free technology for residue-free cone shaping (2). “The technology allows the syringe’s cone hole to be shaped using ceramic materials instead of metal or a tungsten pin, which leaves behind traces of tungsten that can lead to unwanted reactions with the active ingredient, particularly for biologics,” Heymann says. 

In contrast to glass, plastic is shatterproof and lightweight and can be made flexible, soft, or hard depending on the requirements-a versatility that glass cannot offer, notes Jens Friis, vice-president, Europe & Latin America Plastic Packaging, Gerresheimer. “When choosing the appropriate plastic container, it is important to consider whether the drug is solid or liquid and how it is dispensed, taken, or administered,” he says. “Our Duma tablet container, for example, is for solid active ingredients taken orally. This container has already been around for 50 years in a broad and varied range, featuring tamper- and child-proof closures, integrated desiccant, and much more.” 

Friis highlights that Gerresheimer recently introduced alternative packaging solutions made from highly transparent cyclo-olefin-polymer (COP) plastic for new alkaline parenteral formulations and toxic drugs. “COP combines many of the properties of glass with the shatter-resistance of plastic,” he points out. “The COP contact surface also improves the stability of highly sensitive medicines, such as the new generation of biopharmaceutical active ingredients, and minimizes the interaction between the drug and the packaging.” 

“For specific requirements, Gerresheimer has developed the multi-layer Gx MultiShell Vial made from COP and a polyamide barrier layer,” says Friis. “This combination makes it possible to enhance the vial’s oxygen-resistant properties many times over that of traditional COP monolayer vials.” According to him, Gerresheimer produces plastic syringes in Germany for the ClearJect brand, which also uses COP. “Prefillable plastic syringes do not contain any tungsten left over from the production process and are made without any needle adhesive. They are also shatter-proof and customizable,” he explains. “They are similar to glass syringes in terms of their functional properties such as break loose and gliding forces. The highly transparent material makes ideal primary packaging for sensitive medicines for use in oncology, ophthalmology, or other fields of application.”

Heymann points out that for most, deciding between glass and plastic depends on the following questions: How and where will the medicine be used? How will it be dispensed? Who is it for and how will it be administered or taken? “And then, there is still the question of how the medicine is to be bottled,” he adds. “For example, we have agreed with our competitor Nuova Ompi that we will use the same secondary packaging in the form of nests, trays, and tubs to package our Gx RTF vials-which is the well-known Ompi EZ-Fill packaging format. This way the customer can receive identically packaged sterile injection vials from two different manufacturers, which enables them to start filling the vials straight away without the need for any intermediate process steps.”

Glass and plastic complement each other with their specific properties and benefits, notes Friis. “Although the active ingredient is the top priority, many other factors influence the choice of primary packaging,” he says. “One of our key objectives is to increase the efficiency of drugs by ensuring that they are delivered in the most targeted and complete way possible. User-friendliness and safety in application play an important role in everyday use.”

References

1. Gerresheimer, “Perfect Gx Elite Vials Presented by Gerresheimer at CPhI Worldwide,” Press Release, 25 Sept. 2017.
2. Gerresheimer, “Gerresheimer Introduces Metal-Free Syringe,” Press Release, 12 Jan. 2017.

Article Details

Pharmaceutical Technology Europe
Vol. 30, No. 1
January 2018
Pages: 16

Citation

When referring to this article, please cite it as A Siew, “Glass or Plastic-A Question of Use,” Pharmaceutical Technology Europe 30 (1) 16 (2018).