Packaging
TELC: the tamper-evident Luer lock closure with guided-twist-off motion
Friday 02. May 2008 - Gerresheimer combines Luerlock adapter and closure cap for prefilled syringes
Prefilled syringes where the needle is not pre-mounted require an adapter to screw in the needle securely later, on top of this a closure and – ideally – a tamper-evident seal. How intelligently this can all be combined in one is demon¬strated by the Gerresheimer Group in the TELC: a highly advanced, integrated solution for RTF syringe systems (Hall 7, Stand A01).
TELC stands for ‘Tamper Evident Luerlock Closure’, i.e. a tamper-evident combination of closure cap and Luerlock adapter. Its devel¬opment has resulted in a so far unique unit consisting of the tamper-evident closure, screw thread and thermoplastic elastomer (TPE) as the material. The smart assembly comes from the innovation pioneer Gerresheimer Bünder and simultaneously tackles a whole range of problems which, according to the previous standards, were not solved satisfactorily or at best were solved only in a fragmented manner. And their importance on a number of very different levels cannot be underestimated.
Today, for example, most syringe systems can still be opened and closed unnoticed – a shortcoming which favours tampering and even product counterfeits. The Bünder experts thought that the custom¬ary closures were also very much in need of improvement in other regards. The standard here is the so-called tip cap – a rubber cap which has to be removed directly before application with a little jerk but, as the result of mechanical effects, can pop off on its own during transportation or storage. Another shortcoming in the eyes of the Bünde developers was the relatively high level of assembly effort in pharmaceutics production. Previously, the adapter and the closure were placed on the syringe in two individual process steps. One step should at all events be sufficient, they thought. So every¬thing pointed to a system solution consisting of just one part.
“The integrated design including the tamper-evident closure, combined with the material TPE, is the secret of this innovative product concept,” says Burkhard Lingen¬berg, Director of Corporate Communications and Marketing for the Gerresheimer Group. He describes this principle as “really inspired”. The system developers have succeeded, he says, in combining design features and various material properties with such ingenuity as to be compatible with standard technology and economically viable on the bottom line.
In a single unit an extruder which works in two steps initially forms the trans¬parent – and later firmly hardening – plastic adapter made of poly¬carbonate, then the cap coloured according to customer requirements together with its tamper-evident closure made of TPE. As a seal, a stopper made of a customised rubber formulation may optionally be added so that a high-performance unit is created which combines the traditionally tried-and-tested material compo¬nents in a new form.
The pharmaceutics industry needs to mount just one integrated component on syringes – adapter, closure and tamper-evident seal all in one.
The closure cap is twisted off to open – not lifted off. First of all, the controlled twisting motion has the advantage that accidental spillage of the medication – which often occurs with the Tip Cap because of the jerky opening action – is largely avoided. Secondly, so-called pop-off effects are excluded: the cap stays firmly in place until the injection.
The twisting motion releases lugs on the closure cap, which then immediately drop away slightly. It is practically impossible to close the syringe again completely – so it is evident that it has been opened.
Another plus point results from the choice of materials: the Tamper Evident Luerlock Closure can be used for existing products at short notice. All the materials are already familiar and adequately certi¬fied, so new stability tests in combination with the relevant medica¬tion, which can take up to two years, are not required by the multi-function accessory. It was for this reason alone, say the experts, that they integrated the separate rubber seal as an option in their injec¬tion-moulding concept. As it is made of the same material as the familiar tip caps, this seal has been licensed as a primary packaging material for a long time – although plastic could of course also be licensed.
That Gerresheimer has a real hit on its hands with the TELC is documented by a study carried out by an independent market research institute with 110 doctors, nurses and self-injecting patients. The study confirms that the innovative closure has exem¬plary benefits in practical use. Lets briefly summarise them once more: the possibility of unnoticed opening of syringes is excluded, they remain reliably sealed until use, there is no spillage on twist¬ing off the cap, as so often happens during the removal of Tip Caps, and handling is substantially simplified overall – as cited by two thirds of respondents as important plus points for them personally.
Further details about the market study have been summarised by Gerresheimer in a flyer.