Testing Pen Injectors

When developing a pen injector (or injection pen as also commonly known), it is prudent to understand the performance of the device from a clinical perspective. ISO have a standard that details suitable methods for determining the dose accuracy of a pen injector, and this standard is called ISO 11608: “Needle based injection systems for medical use – Requirements and test methods”.ISO 11608 – what does it cover?This standard has five parts at present –

• Part 1: Needle based injection systems – which is the primary part of this standard
• Part 2: Needles
• Part 3: Finished cartridges – requirements and test methods
• Part 4: Requirements and test methods for electronic and electromechanical pen injectors
• Part 5: Automated functions

What tests are involved?There are a number of tests involved with meeting the performance requirements of this standard. For a mechanical pen injector, then the tests stated in Part 1 are most applicable. The tests for a mechanical pen injector are –

• Visual Inspection
• Container inspection
• Determination of dose accuracy at cool, standard and warm temperatures
• >Determine of the last dose accuracy
• Life-cycle testing
• Free-fall testing
• Dry-heat and Cold-storage testing
• Damp-heat testing
• Cyclic testing
• Vibration testing

For electro-mechanical pen injection system, the requirements and test methods stated in Part 4 are applicable. Additional tests required by Part 4 include Electromagnetic Compatibility (EMC) testing, Dust Ingress (to IEC 62539) and Electrical safety testing (to IEC 60601-1-1). We see more and more electronic and digital pen injectors which makes Part 4 useful to comply with.Labelling and Instructions for UseTesting to ISO 11608Testing to this standard is not a quick task to do – a typical duration is 4-8 weeks, and so if you are developing a pen injector that requires performance testing to this standard, this amount of time should be considered. Also to consider are the test equipment, and the number of test samples the testing requires. All should be determined in a Test Protocol and once the results generated by the testing, analysed , they are detailed in a Test Report.THAY Medical can assist with generating data to show compliance to this globally recognised standard. We can perform this testing and show how accurate the dose is of the pen injector, update Instructions for Use and device labelling as well as perform the EMC evaluation for any digital or electro-mechanical pen injectors.If you have any questions on ISO 11608, please do not hesitate to contact THAY Medical. We would love to hear from you.The staff at THAY Medical