Prefilled Syringes Meet Growing Demand

Prefilled syringe innovations increase patient and caregiver safety and efficiency and reduce waste of product and packaging materials. “Since it is already packaged ready for the injection, the prefilled syringe saves time and avoids unneeded handling prior to the actual application, minimizing the risk of the injection errors, dilution errors, or non-sterility issues [that are a risk in] multi-dose containers,” explains Wenzel Novak, global senior director of business development at Gerresheimer Medical Systems. Novak estimates that prefilled syringes currently account for 10–15% of the parenteral market and anticipates rising demand.

“If you look at the top 40 injectable products, all are being used with prefilled syringes,” reports Dr. Nicolas Brandes, director of product management, Polymer Prefilled Syringes and Vial Containment at West Pharmaceutical Services.

Prefilled syringes can be made of glass or plastic such as cyclic olefin polymer/cyclic olefin copolymer (COP/COC) or polypropylene (PP). Glass dominates in most markets. Novak predicts, however, that the share of co-injection-molded COP/COC prefilled syringes will grow from 2% to more than 5% during the next decade.

“We have seen more approvals for products in plastics especially during the past five years,” reports Brandes. He notes plastic syringes often are chosen for specific applications such as contrast imaging agents, hyaluronic acid, and Botox as well as for products that are sensitive to silicone oil. Plastic syringes also function well in auto-injectors.

According to Novak, about 60% of prefilled syringes are staked-in needle syringes, but there are considerable regional variations. The most common prefilled syringes are 1-mL long and 1-mL short. The most prevalent applications include anti-coagulant (glass 1-mL long), vaccines (glass 1-mL short), and isotonic solutions where PP is the material of choice. “With the existing COVID-19 challenge, a significant increase in vaccines is expected worldwide,” says Novak. This growth will stem from COVID-19 vaccines as well as heightened interest in established vaccines (e.g., flu).

Prefillable syringes are delivered as bulk goods or ready-to-fill (RTF). Gerresheimer’s bulk syringes are provided as unsterilized glass bodies in flat (Rondo) trays or customized packaging designs (e.g., bags). Its Gx RTF syringes are presented as washed, sterilized RTF components to pharmaceutical and contract manufacturing operations and are available in glass or plastic. Fill volumes range from 0.5 to 5.0 mL, with the most common volumes falling between 0.5 mL and 3.0 mL.

Prefilled syringe innovations

Innovations from suppliers accentuate the ease-of-use attributes of prefilled syringes and focus on adding sizes (particularly for larger volumes), reducing waste, and patient and caregiver comfort and safety.

Gerresheimer has expanded its range of prefillable polymer syringes for sensitive biologics, biosimilars, and biobetters to include a Gx RTF ClearJect COP needle syringe, 1.0-mL luer lock.

At West Pharmaceutical Services, line extensions include insert needle syringes (the plastic version of a staked needle glass syringe) and more needle sizes and product volume options. “In the past three to five years, we have seen more approvals in the larger 2.5-mL format,” reports Brandes. The larger volume reduces the number of syringes needed per dose and improves efficiency and comfort. There’s a trend toward finer needles too. “Smaller, thinner needles mean less pain,” he explains.

User-friendliness is the goal behind a collaboration between Gerresheimer and Stevanto Group whereby Stevanato supplies its ITC twist-off closure system for Gerresheimer’s Gx RTF luer lock syringes. The integrated seal cap consists of an elastomeric component, which is available in different formulations, and a rigid, translucent polymer cap. Advantages include greater stability and shelf-life protection versus traditional luer cone systems (1).

Prefilled syringes offer sustainability benefits by eliminating multi-dose vials and related production and handling as well as product waste associated with leftover product. Still, says Brandes, “there’s a lot of room for improvement. Current systems create a lot of waste.” But efforts are being made to reduce scrap rates and to recycle tubs that hold nested containers during the fill/finish process. 

To meet the priority of product safety, suppliers seek designs to prevent needlestick injuries and to protect product quality by minimizing particulates and eliminating product interaction with tungsten or silicone residues. For tungsten-sensitive products, Gerresheimer Biological Solutions offers a metal-free manufactured syringe. With this patented technology, the pin used for conical shaping is made of a ceramic rather than tungsten or another metal.

Silicone oil is commonly used to facilitate syringe performance but can cause aggregation and particulate problems for sensitive biologics. “There’s a push by ophthalmologists and regulatory bodies to move away from siliconized formats,” reports Brandes. “Some patients have reactions to silicone, and over time with repeated injections, the material can accumulate [in the eye],” he explains.

One silicone-free option combines ImproJect plungers from W.L. Gore & Associates with syriQ BioPure silicone-free syringes from SCHOTT. The system opens the door for many sensitive products to move into the prefilled syringe format. Until the advent of a silicone-free design, “Pharmaceutical manufacturers seeking to avoid silicone-induced aggregation and sub-visible particles have had to choose vials even when they wanted to offer other delivery options,” said Christiane Gumera, product specialist at W.L. Gore & Associates. Careful attention to syringe geometry and dimensions of the syriQ BioPure syringes helps ensure a consistent gliding force and injection duration over the shelf-life of the product and maintains container/closure integrity without the use of silicone. Ultra-low tungsten residuals and minimal cannula adhesive residuals further reduce the extractible profile and the risk of container/drug interactions (2). 

To prevent potentially hazardous accidental needlesticks and comply with regulations in various parts of the globe, some syringes like Gerresheimer’s InnoSafe product incorporate a pre-applied, passive safety device. With the pre-applied device, there’s no need for post-filling assembly equipment or for healthcare professionals to install a guard before an injection is given. Advantages include improved compatibility with auto-injectors and a completely hidden needle that gives patients with needle-phobia a better experience. The design also prevents accidental reuse and runs on existing fill/finish lines without any additional equipment or process steps.

Finally, COVID-19 has spurred the development of prefilled syringes, particularly with regard to low-temperature storage. Brandes predicts, “Right now all COVID-19 vaccines are in vials, but in the next two to four years we will see a novel type of syringe that handles -80 ºC.”

References

1. Stevanato Group, “Stevanato Group Sings an Agreement with Gerresheimer to Provide Its Integrated Twist-off Closure System Solution, ITC, for Gx RTF Syringes,” Press Release, Oct. 6, 2020,

2. PharmTech Editors, “Glass Syringe System Reduces Injection Force without Silicone,” PharmTech.com, Nov. 21, 2019.

About the author

Hallie Forcinio is packaging editor for Pharmaceutical Technology.