Many industry veterans know that parts of ISO 11607 are up for interpretation. There are portions you shall (must) follow, and there are areas that are left up to you and your organization to determine how they relate to your products. This is our quick, expert guide to the areas of ISO 11607 that are more open to interpretation than others.
The authors understood that no one better knows a product, its intended use, its patient population, or the risk of potential harm and occurrence of a sterile barrier breach, than its development team. For instance, when engineering packaging for a device to treat critically ill patients, the severity and occurrence of a sterile barrier breach could be high. As such, a larger sample size during design verification could give higher statistical confidence that the packaging design provides optimal sterile barrier integrity for a high-risk patient population.
On the flip side, imagine a device being developed primarily for use in healthy patients. In this instance, the risks relating to severity and occurrence of a sterile barrier breach may be lower, indicating the appropriateness of a smaller sample size. Each organization's responsibility is to interpret the ISO 11607 requirements and develop quality procedures and processes that apply to their specific devices accordingly. Find out more about the importance of design control and its application to packaging by watching this webinar.
The age-old question: should performance and stability testing be combined? ISO 11607 has come a long way in clearing up this confusion. The current language states, “Stability and performance testing are separate entities.”.
Although this statement seems very clear, historically, some medical device manufacturers have combined stability and performance procedures. Since the latest revision of ISO 11607 was released, many MDM’s have updated their procedures to separate the two testing categories. That said, some MDM’s have kept them combined. It can be challenging to gain buy-in from cross-functional teams when it comes to updating a legacy quality system. Especially when separating the two testing categories means less testing. Developing effective new procedures and justifications is a major undertaking. Unfortunately, there is no absolute answer. If your company opts for separate performance and stability testing procedures, it can be an opportunity to educate your stakeholders and drive compliant change. This can, in turn, accelerate project timelines and prevent over engineering while benefitting your bottom line.
ISO 11607 requires worst-case evaluation on many fronts, including worst-case device configurations, worst-case usability scenarios, and my personal favorite, worst-case sterile barrier systems. The standard states, “worst-case considers exposure to all the specified sterilization processes and most challenging contents”. Addressing this requires a solid understanding of how the device can impact the sterile barrier, its intended use, and how the sterilization process impacts the sterile barrier. Some quality systems also call for consideration of worst-case seal strength, worst-case distribution simulation, and worst-case shipping configuration (i.e., 1 pack vs. 5 pack). The packaging engineer is responsible for the completion and documentation of all evaluations in the test plan. From there, a cross-functional team will review and approve or modify the findings.
The challenge to worst-case evaluations is that some of this information can be subjective, making it important to maintain a consistent approach across similar sterile barrier systems. An example would be if you’ve determined that the worst-case scenario for your sterile barrier system is to undergo multiple cycles of gamma radiation compared to receiving a single, higher dose concentration. If so, then the next steps would be to apply that finding to similar sterile barrier systems. There is no one-size-fits-all to determine worst-case rationale for your design verification. It helps to take a sound, scientific approach and discuss with your cross-functional team if you get stuck.
With the latest version of ISO 11607 comes the usability requirement: "A documented usability evaluation shall be conducted to demonstrate that sterile contents can be aseptically removed from the sterile barrier system for presentation." This new requirement can be met in several ways. Some are more scientific than others and depend on your organization’s expertise in this discipline. Satisfaction of the usability requirement is also subjective to the reviewer/auditor looking at the data. There is a wide range of opinions for how (and whether) this requirement has been satisfied. Solutions range from an end-user survey confirming that the device could be aseptically removed and presented from the sterile barrier system during clinical trials or simulation labs, to a comprehensive technical usability study. Because this requirement is newer, compliance is loosely defined. I expect that to change in the coming years.
In summary, while ISO 11607 is an excellent standard to show compliance to medical device regulation, many decisions must be determined based on specific device and organizational requirements. To learn best practices, reach out to your network, ask your supplier, or work with your internal cross-functional team. We are all in this together and committed to making healthcare better one sterile package at a time.