Stability Studies and Transport Validation are both Vital Aspects of Design Validation for Injector Systems.

The article written by our Managing Director is one of several papers supplied to the publication by Medical Engineering Technologies.

These include:

• An explanation of biocompatibility studies for combination devices.
• Extractables and leachables for injectables. 
• Design validation studies for delivery devices.
• The  importance of choosing a high quality partner for batch release and design validation testing.

The transport and stability paper discusses a subject which is often left late in a prefilled syringe or auto-injector development project. They are important and can lead to nasty surprises if verification studies are not considered early on.  Problems are rare in a transport study and they can be easier to rectify that those encountered in a stability study. Both require evidence that sterility is maintained as well as dose accuracy and the other performance requirements found in ISO 11608 and ISO 11040.

Stability studies can extend over a considerable period of time and this should be considered in project planning. Many formulations for injections are specified for storage at 4 to 8°C. Whilst accelerated ageing can be used to gain comfort, testing at the end of the full storage period at the specified temperature is required.  Storage at higher temperatures to accelerate the ageing process can cause false negatives. Some of the reasons for this include; denaturation of proteins, chemical interactions within the formulation or between the formulation and the siliconisation, or evapouration of fluid at the needle tip.

Early engagement with MET will help ensure that your project runs smoothly.