This delivery mechanism is frequently chosen for its swift action, its capacity to deliver orally ineffective medications, its efficacy in urgent interventions and its ability to provide essential nutrients to patients who are unable to consume food normally.
Parenteral pharmaceuticals primarily encompass injectables — therapeutic agents administered by healthcare practitioners in clinical settings — such as vaccines, intravenous infusions and infusionals, which are supplemental fluids used as adjuncts to these treatments.
The packaging system for these vital medications represents a sophisticated feat of engineering, comprising the primary packaging itself — typically a vial or bottle — a rubber stopper and a standard or tear-off aluminium seal.
These vials are crafted from glass with diverse material specifications, manufacturing techniques and attributes that can be tailored to the specific properties and demands of the drugs.
Glass types
The glass type employed is meticulously selected based on the characteristics required for optimal drug containment.
Borosilicate glass is renowned for its superior mechanical resilience and impressive hydrolytic stability, rendering it suitable to contain a wide spectrum of injectable products with acidic, neutral or mildly alkaline pH levels.
Soda-lime glass, in its Type II version, conforms to the stringent standards established by international pharmacopeia for parenteral applications by way of specialised surface treatments.
It is particularly well-suited to package both injectable and non-injectable formulations comprising acidic and neutral solutions.
Finally, Type III, a low-alkali sodium-calcium glass, exhibits exceptional hydrolytic resistance compared with standard (food and beverage) applications, particularly when exposed to abrupt temperature fluctuations.
This makes it ideal for non-aqueous or powdered injectable preparations ... with the exception of drugs requiring lyophilisation. The glass used for parenteral drug containment originates from two distinct cutting-edge manufacturing processes: premium moulded glass and tubing glass.
Premium moulded glass containers for parenteral application combine state-of-the-art glass manufacturing technologies with stringent GMP requirements. This combination transforms the molten glass into a finished parenteral vial that’s ready for distribution to pharmaceutical manufacturers or contract manufacturing organisations (CMOs).
This technique is specifically designed for the fabrication of premium borosilicate glass, the benchmark for parenteral and injectable pharmaceutical applications. Conversely, tubing glass containers necessitate a two-stage process.
They are formed by converting a glass pipe into a vial using localised flames and a series of steps to achieve the desired configuration. Pharmaceutical manufacturers can select from various options, considering factors such as the heat applied during vial formation.
This directly influences the level of extractables on the surface owing to the vaporisation of volatile glass components and the condensation of vapours on the cooler inner surface, creating “rough spots” with distinct chemical compositions.
Vials and tubing
Premium moulded vials exhibit superior mechanical and chemical properties, whereas tubing vials offer enhanced aesthetic surface qualities. Discrepancies in other tested parameters are negligible.
Larger drug formats favour moulded glass vials owing to their mechanical strength, whereas smaller formats often use tubing glass vials. Primary packaging for parenteral use also displays considerable diversity in format sizes, with injectables typically packaged in smaller formats and infusionals requiring larger ones.
Sizes range from 2–1000 mL. Larger formats may feature printed level markings and specialised designs for compatibility with hospital infusion bottle hangers.
Supplementary services, such as ready-to-use and ready-to-sterilise options, can be provided upon client request, enabling pharmaceutical manufacturers to concentrate on their core competencies.
Further controls, including 100% visual inspection and customised post-production quality checks, can also be implemented to meet specific client needs.
Furthermore, detailed data-driven information can be furnished to expedite customer validation procedures, along with certified analyses of extractables testing that helps companies to navigate diverse regulatory landscapes.
The integrated packaging system is completed by a rubber stopper, fabricated from high-quality rubber to minimise drug interactions, and aluminium closures (either standard or tear-off).
Although standard aluminium caps employ a mechanism akin to those used for soft drinks, tear-off caps consist of a predrilled aluminium closure with a plastic cap, offering enhanced usability for healthcare professionals and customisation options for improved drug recognition in clinical environments.
Looking ahead
This describes the current state of primary packaging for parenteral drugs. Although the distant future may witness a shift towards wearable devices, particularly for chronic conditions requiring continuous drug delivery, the near future promises advancements in packaging engineering along several avenues.
The primary driver of innovation in container features remains the raw material: glass.
Ongoing refinements in the treatment of the internal glass surface aim to maximise resistance to extractables and leachables, thereby optimising bottles for intravenous drug administration.
Another focus is enhancing container durability, particularly the external glass surface, through research into novel technologies such as silicon coatings, chemical vapour deposition (CVD) and plasma treatments.
These advancements aim to mitigate breakage risks during sterilisation, depyrogenation and handling throughout the supply chain. Furthermore, the identification of novel technologies and processes to reduce leachables and extractables is paramount.
The continuous testing and analysis of extracted elements is crucial to ensure compatibility with increasingly aggressive drug formulations. This pursuit of enhanced stability extends to closures, with ongoing research into innovative treatments to improve compatibility.
The development of next-generation glass bottles offering superior chemical neutrality, shock absorption and improved assembly line flow characteristics is also a key area of focus.
Innovation extends beyond material advancements to encompass a holistic reimagining of containers as complex systems with integrated features.
This includes enhancing integration within the pharmaceutical value chain and improving usability for healthcare professionals to simplify and safeguard drug administration.
The challenges experienced by professionals during recent health crises underscore the need for packaging designed for ease of use, speed and safety.
Several innovative products and concepts are being explored to address these needs, facilitating parenteral drug reconstitution and administration while minimising product waste and enhancing safety through features such as Luer-lock systems.
Pharmaceutical companies are actively evaluating these advancements with initial scale-up trials now under way. Enhanced traceability throughout the supply chain is another critical objective.
Developing innovative solutions to track and trace drugs through primary packaging could be transformative, especially for high-value pharmaceuticals. Collaboration and cocreation are essential to advance parenteral packaging as a system.
Continuous dialogue, long-term planning and a shared responsibility model are crucial for the success of these partnerships and, ultimately, for the efficacy and safety of therapeutic drugs in the global market.
