Pushing the barrier: Reducing risks and time to market for prefilled syringes

For coated elastomeric closures, barrier properties alone are no longer enough to meet the needs of biologic drug packaging. Dr Susan Dounce, senior manager, business development and innovation, injection systems, Datwyler Sealing Solutions writes.

Reducing or eliminating silicone oil is being recognised as a means to mitigate risks and reduce time-to-market. Datwyler’s Omni Flex fluoropolymer coating technology provides numerous advantages and benefits in prefilled syringes beyond barrier properties, especially regarding stability, quality and end user experience.

In the conservative, data-driven industry of parenteral packaging, market trends indicate a growing demand for fluoropolymer coated elastomeric closures, primarily to mitigate risks related to drug stability and compatibility. Rubber components are of high importance, particularly in the segment of liquid pharmaceuticals. Here, the drugs are in constant contact with the rubber component, e.g. the plunger of a pre-filled syringe or the closure of a vial.

To meet the evolving needs of the biologics industry, the Omni Flex fluoropolymer coating is the first coating to both provide barrier properties and to eliminate the closure as a source of silicone oil-based subvisible particles (SbVPs) at the same time. This is particularly critical with protein-based biologics, as a reaction to silicone leachable can cause the proteins to aggregate and eventually diminish the drug’s efficacy.

As a consequence of the coating’s chemical composition and method of application, Omni Flex Coated Plungers (Omni FlexCP) not only have barrier properties that result in superior chemical compatibility, but also have the added benefits of a significant reduction in SbVP levels and highly consistent delivery forces. This allows a safe and consistent administration of the drug even after a longer time of storage. Studies show that the plungers also have a highly consistent glide force with ageing. The temperature and humidity at which ageing studies are performed (refrigeration, room temperature, accelerated ageing) have a negligible influence on glide forces for Omni Flex Coated Plungers. Omni Flex CP was launched in 2009. Today, it is the best performing fluoropolymer-coated plunger technology addressing the compatibility and performance challenges of the biologics industry and beyond.

Omni Flex fluoropolymer coatings are applied to several product classes, including Omni Flex CP (syringe plungers), Omni Flex Plus and Omni Flex 3G (vial stoppers). Omni Flex CP is developed in a two-step process. In the first step, the proprietary fluoropolymer film is applied by a tumble spray coating. The second step consists of a post-treatment process that provides sufficient thermal energy to bond the coating covalently to the Bromobutyl substrate and to form a smooth, continuous fluoropolymer film. Due to the line-of-sight nature of the spray coating, the entire plunger surface is covered, with the exception of the interior of the plunger-rod cavity. The total coverage by the Omni Flex coating stands in contrast with the partial coverage of most film coatings and therefore offers the benefit of providing a complete barrier. The total coverage of the fixed lubricious coating also eliminates the need for siliconisation of the plunger rills. This eliminates the largest source of subvisible particles and allows Omni FlexCP particle levels to be some of the lowest in the industry. And, in combination with the optimised product design, the elimination of siliconisation results in glide forces for Omni Flex CP which are highly consistent down the length of the barrel and from plunger to plunger. Furthermore, the spray-coating process easily lends itself to coating custom designs for innovative drug delivery devices.

Additionally, the reduction or elimination of silicone oils in rubber components and closures can reduce time-to-market. As recognised by the FDA, the interaction of proteins with silicone oil can present a risk to the safety and efficacy of therapeutic proteins.

All Omni Flex coated products are produced aligned to our state-of-the-art First Line approach. Today, primary packaging component manufacturing is considered to be an extension of the drug manufacturing process itself. Therefore, all facilities implementing the First Line manufacturing approach are designed to meet the evolving standards of the parenteral industry.

Apart from the Omni Flex coated plungers, we also manufacture needle guards and tip caps as well as closures for vials and for containers for liquid pharmaceuticals and biologics. The total coverage provided by the Omni Flex coatings can also easily be utilised in coating custom designs to fit the customers’ specific needs.

Datwyler has been an important player in the health care sector and has grown to a market share of over 20 percent in the market for pharmaceutical rubber components. This not only makes the company a leading global player in the industry, but also means every fifth syringe and pharmaceutical container worldwide is sealed with a Datwyler rubber component.