Prefillable Syringes 101

Prefillable syringes have become an increasingly important option in the packaging and delivery of injectable drug products. The prefillable syringe serves two major purposes for the administration of a drug. The first is as primary packaging by assuring that there is no adverse effect on the identity, strength, quality, purity or potency of the drug over its shelf life. Second, a prefillable syringe is a delivery system designed to administer the appropriate amount of the drug to the patient reliably

There are two major types of prefillable syringe systems available:

• Glass-based systems
• Plastic-based systems

Traditionally, a prefillable syringe barrel has been made from glass tubing. These glass tubes are transformed by heat into the barrel that is used to hold the drug product. Syringe manufacturers typically form and process the glass and purchase the complementing elastomeric components (e.g., plungers, tip caps, needle shields) that complete the primary package from an elastomeric closure manufacturer.

The benefits of glass systems include:

• Health care practitioners’ long history of familiarity
  with the product
• The majority of prefilled syringes in the marketplace
  are glass with elastomeric components
• There are multiple proven suppliers

There are, however, drawbacks:

• Breakage
• Dimensional variation
• Potential surface reactivity
• Particulate contamination
• Adhesive or other potential leachables
• Inconsistent application of silicone oil (added for functionality)
• Variation in functionality (break loose and extrusion)

Plastic-based syringe systems are gaining acceptance because of their benefits compared to glass systems. The Japanese market, which is well known for its high quality, has transitioned over 50% of its syringes to plastic because of its superior performance.

The most widely used prefillable plastic syringe systems are manufactured from cyclopolyolefin (COP) resin. These systems are manufactured to very high quality standards and to tight dimensional tolerances. As there are many types of plastics, it is imperative to understand the unique characteristics of the plastic syringe system being evaluated because the package choice is critical in ensuring the long-term success of a pharmaceutical or biopharmaceutical drug product.

The benefits of plastic-based systems include:

• Break resistance
• Design flexibility
• Tight dimensional tolerances
• Decreased surface reactivity
• Less absorption/adsorption of the drug
• Compatible with high or low pH

To learn more about prefillable syringe systems, click here.