Medical Device Packaging Shelf Life Testing and Validation

Medical device packaging aims to ensure sterility, safety, and effectiveness of the device from manufacture to the point of use. A tiered system of packaging is used for medical devices. The packaging level is defined by the proximity to the device. Primary packaging remains in direct contact with the device. Secondary packaging protects the primary package and provides information on the device. The tertiary packaging is used for bulk shipping and handling. Medical device packaging shelf life is the period during which it maintains the device’s performance, safety, and, if applicable, sterility. In this blog, we will focus on testing and validation of medical device packaging shelf life. Additionally, we will discuss the importance of packaging shelf life testing and validation.

What is medical device packaging shelf life?

Medical device packaging shelf life refers to the period during which the medical device and its packaging system can maintain their intended performance and sterility. During this period, the packaging will protect the medical device against external factors, such as microbial contamination, humidity, temperature changes, and physical damage. The shelf life is impacted by several factors related to the packaging itself, the device, and storage conditions. If the packaging fails, the device inside will become non-sterile or damaged, rendering it ineffective. Thus, a medical device with a failed packaging system will pose risks to patients and become a liability for manufacturers. Thus, the shelf life of the packaging system has to be determined by rigorous testing. Hence, validation and testing of medical device packaging shelf life is of vital importance during both the product development phase and post-market surveillance.

Factors influencing medical device packaging shelf life

1. Packaging materials: The physical and chemical properties of the packaging materials can degrade over time. This affects the packaging’s ability to maintain a protective and sterile barrier. Additionally, sterilization method compatibility is another factor. The chosen packaging must be able to withstand the sterilization process. Furthermore, the barrier properties of the chosen material is an important factor. An effective sterile barrier system prevents the ingress of microorganisms, moisture, and gases.
2. Package integrity: The seal is the most vulnerable part of the sterile barrier system. Improper sealing parameters or physical damage can compromise the seal, risking contamination. The seal should last the full medical device packaging shelf life. Additionally, resistance to damage is another crucial factor. During transport and handling, the packaging must be durable enough to withstand impacts, vibrations, and compression. Inability to withstand damage will lead to tears, punctures, or crushed packages. 
3. Environmental and storage conditions: Both the materials of the device and its packaging are susceptible to environmental conditions. Fluctuations in temperature and humidity can accelerate degradation and reduce shelf life. Moreover, improper handling, such as dragging packages across a shelf, can cause damage that compromises the sterile barrier. The cleanliness, air quality, and lighting of the storage area are all factors.

Types of medical device packaging by layer

Medical device packaging type is determined by its proximity to the medical device.

1. Primary Packaging: This layer is in direct contact with the medical device and must maintain its sterility and protect it from contamination. Flexible, single-layer or double-layer sealed packages made from materials, such as Tyvek/paper, nylon/Mylar, or foil/nylon, are used as the primary packaging. Rigid plastic trays with a backing are often used for smaller items or devices requiring secure positioning. Durable containers that can be reused are used for larger, heavier devices. Woven textile materials or non-woven fabrics are used as sterilization wraps.
2. Secondary Packaging: This layer encloses the primary package to provide additional protection and facilitate handling. It allows for branding. Cartons and boxes made from paperboard or corrugated fiber board are used. They add a protective layer and provide space for instructions and labelling.  
3. Tertiary Packaging: This is the outermost layer designed for bulk storage, distribution, and long-distance shipping. Crates and pallets are used to consolidate multiple secondary packages for stable and efficient shipping. 

Why is packaging shelf life testing important?

1. Regulatory compliance: Regulatory authorities require medical device manufacturers to validate the shelf life of their packaging systems. Manufacturers must demonstrate that the sterile barrier system maintains integrity throughout the intended product shelf life. Without proper testing of packaging, manufacturers risk product recalls, market rejection, or delayed approvals.

2. Patient safety: Compromised packaging can compromise the sterility of the medical device. This can lead to infections, surgical complications, or device malfunction. All of these can harm the patient and have a detrimental outcome. Thus, shelf life testing ensures the product will remain safe to use until the expiration date of the product. Hence, medical device packaging shelf life testing ensures patient safety.

3. Product credibility: Healthcare professionals and distributors rely on shelf-life dates while using medical devices. A breach in packaging integrity can damage the product, thereby impact product credibility. This will impact brand reputation and business relationships. Validation and testing of device packaging demonstrate the company is committed to delivering safe and reliable products.

Common medical device packaging shelf life validation tests

We have presented some common tests performed to verify that the device packaging maintains its integrity throughout its shelf life.

1. Package integrity tests: This test ensures there are no leaks, punctures, or weak seals. Dye penetration test (ASTM F1929), bubble leak test (ASTM F2096), and helium leak testing are some of the common tests.

2. Seal strength tests:  This test is required to check the seal is strong enough to protect the device but not too hard to open

3. Microbial barrier testing: Tests to check whether the sterile barrier can prevent microorganism entry. Simulation of exposure to microbes in storage and shipping conditions are done.

4. Environmental conditioning: Evaluates medical device packaging performance under stress conditions, such as compression, high/low temperature, humidity, and vibration.

Key steps in packaging shelf-life validation

We have presented the key steps in medical device packaging shelf life validation.

• Packaging material selection: Choosing the right packaging material is a vital step. The packaging material has to be compatible with the device and sterilization methods, durable, and provide a microbial barrier. The common materials used are Tyvek®, foils and laminates, polyethylene films, and medical-grade paper.
• Package design qualification: Sealing strength, sterilization method compatibility, material integrity, and usability by healthcare staff are evaluated.
• Accelerated aging tests: How the packaging will perform over months or years is evaluated. Accelerated aging simulates the effect of time in a short period by exposing the packaging to elevated temperatures. This tests help understand the impact of time on the packaging. However, real-time aging studies should be used to support the findings.
• Real-time aging: Real-time aging is the standard test for shelf-life validation. Devices are stored under normal conditions. Then, they are tested periodically to confirm integrity and sterility over time. Real-time aging provides definitive evidence of long-term performance of the medical device packaging.

5 best practices for packaging medical devices 

1. Incorporate regulatory guidelines for packaging early on.
2. Align packaging validation with sterilization validation timelines.
3. Only use accredited labs for testing package integrity.
4. Accelerated aging tests should be supplemented with real-time aging studies.
5. Post-market surveillance studies should be used to review packaging performance in real time.

Emerging trends in medical device packaging

• Sustainable packaging: Addresses environmental concerns by using recyclable or bio-based materials for packaging medical devices. It aims at reducing overall waste.
• Smart packaging: Integrates technology, such as sensors or indicators, to monitor critical environmental conditions, track location, or verify product authenticity throughout the supply chain.
• Patient-centric design: Packaging design focused on ease of use and accessibility for the end user. Features, such as easy-open seals and clear labeling to prevent medication errors, are used for a more patient centric packaging design.

In this blog, we have discussed the importance of medical device packaging shelf life testing and validation. For developing a regulatory compliant, audit-ready, and reliable medical device packaging, email at [email protected] or call/Whatsapp on 9996859227.