Breaking Glass

Risk mitigation is clearly a big issue for the pharma industry, and companies must go to great lengths to ensure that the necessary tools are in place to manage every potential risk. To this end, we’ve seen countless innovations across the field to ensure that development activities are well documented, that production processes are validated, and that clinical trials are run efficiently. Additionally, we’ve seen greater focus on the patient interface, which has spurred the development of patient-friendly drug delivery devices, such as auto-injectors, pre-filled syringes and ancillary systems.

Despite these innovations, one area of drug packaging has remained more or less unchanged for decades – the packaging for parenterals. Container shelf life plays a very important role in ensuring the stability and reliability of the drug product. The traditional material of choice for primary packaging is borosilicate glass. Glass is a natural product with excellent intrinsic properties; it is inert and virtually gas impermeable. Unfortunately, there are also some drawbacks – glass is fragile, difficult to control within the manufacturing process, and its batch-to-batch quality varies due to the natural source of its ingredients.

Today, traditional glass primary packaging must cope with the requirements of a new generation of sensitive biological drugs that do not tolerate any impurities. Typical borosilicate glass comprises 70 to 80 percent pure silicon dioxide; the rest of the composition includes metals, such as boron, aluminum, and sodium. These metals can create problems with the drug formulation, including direct reaction with formulation components that may shift the pH of a biological drug product and trigger the formation of particles. Ion exchange and hydrolysis of the glass can result in glass delamination, which produces particles that may cause contamination. Ions or particles leaching from glass packaging into the drug are also a worry.

The industry is doing the best it can to manage the risk of leaching, but it’s a complex science and likely to remain a challenge for some time. In addition, integrating glass pre-filled syringes and cartridges with injection molded mechanical devices, such as auto-injectors, is tricky. The brittle qualities of glass and the manufacturing tolerances used are wider when compared with plastic pre-prefilled primary containers, which affects auto-injector reliability. 

Revolutionary thinking is needed to tackle the glass parenteral packaging problem. One solution would be to start from scratch with a new design for a primary packaging system that can cope with all the industry’s packaging requirements, as well as being unbreakable and having a glass-like appearance with glass-like barrier properties. Such a design would provide consistent quality for ensuring defined interaction with the drug formulations, and would be compatible with existing industrial filling lines. Right now, we live in very exciting times as the parenteral packaging industry is undergoing change in both new drug development and primary packaging. New and established manufacturers are entering the market with creative packaging concepts to address special needs coming through pipelines, including polymer syringes and vials that use multilayer plastics with oxygen scavenging materials to simulate glass. Recent product offerings combine polymer science and plasma technology to produce hybrid packaging systems that use high precision injection stretch blow molded manufacturing and clean pharmaceutical grade cyclic olefin polymer (COP) with a plasma-deposited glass-like internal barrier coating. 

I believe that it is about time we embraced these kind of innovations in primary packaging; they will help to change the parenteral packaging landscape for the better. They will not only be safer in terms of eliminating problematic leachables, but will also provide better manufacturing tolerances, and offer more reliable performance when combined with other drug delivery systems, such as auto injectors. The end result? Safer medicines and hopefully improved patient compliance. 

My concern is that pharma can be a conservative business and reluctant to break from tradition. Whenever a new innovation is seen in formulation or a primary container, it is necessary to understand the regulatory requirements and the potential new failure modes – but if you don’t have the courage to embrace new packaging concepts for parenteral drugs, then the risk of failure significantly increases. As an industry, we should be using the most innovative and modern options that have been designed to meet the needs of drugs today.