Shelf Life Statement for Biopharmaceutical Plastic Consumables

1. Introduction

Shelf life or expiration date of the pharmaceutical consumables needs to be considered as plastics can age and their physical and compatibility properties may change over time. These changes can be increased by factors like temperature, heat, humidity, and additives. Also, UV absorption and sterilization method such as Gamma irradiation can degrade the polymer materials through oxidation and shorten their service life. It is necessary to test films to understand the structure-function relationships and establish the length of time that the films can be stored and used under certain environment.

2. Techniques to Establish Shelf Life of Consumables

Shelf-life can be measured through accelerated-aging techniques based on a fundamental understanding of polymer behaviors, however, it is quite difficult to derive an accurate correlation between accelerated and natural performance, real-time ageing is undoubtedly still the best way of accurately determine long-term performance. Sometimes it is essential to perform both accelerated and real-time ageing tests in order to gain reliable information.

To establish the shelf life, reprehensive sample products should be carefully chosen to accurately represent the construction of the entire product line, and multiple samples from multiple production lots should be used during the study at any given time point. A separate storage study is needed to evaluate the effect of aging on the various chemistries.

Real time aging testing is usually completed at the normal storage conditions, which is also the same as the supplier recommended conditions including temperature, amount of lighting, moisture, pressure and environmental elements. Accelerated aging study is often completed under aggravated conditions, such as high temperature and moisture, sometimes at highest estimated usage pressures and in unfavorable environments if applicable.  

If a sample product fails during the study, a failure analysis will need to be conducted through the approved deviation procedure. The mode of failure and impact on product quality will be assessed. If the failure is deemed to be anomaly, the study can be continued as planned. In all cases, any success and failure observed during the study should be properly documented.

3. Statement and Labeling

Shelf life statement may be found in product labels, product certificate and/or separated shelf-life document provided by the supplier. The shelf-life is often given from the date of manufacture to the expiration date, the material storage condition prior to shipment and special handling instructions should be provided to inform the end-users. It is worth noting that the packaging condition should always be included by the supplier and visual inspection should also be carefully performed upon receiving of the product by the end-users. For sterilized items, because a consumable material can be stored several months before being sterilized, the shelf-life should be given based on the date of the irradiation processing or time of sterilization. In addition, it is important to note that the shelf life for components and final assemblies can be different, for assemblies, the manufacturer’s expiry is driven by the component with shortest post irradiation expiration date. Therefore, it is always a good practice to keep tracking and record of all the components, as expired component can become the weakest link of the whole assembly and cause unexpected issues. The following provides an example of checklist for end-users to assess consumable shelf-life statement.

What document is provided to inform the shelf life and in what format?
Accelerated shelf life or real-time shelf life has been performed?
If the shelf life is given on multiple documents, are they consistent?
Is the recommended storage condition provided?
Are recommended storage conditions applicable for end-user?
Is the consumable sterilized to establish shelf-life study? What is the sterilization method?
For irradiated consumables, is the shelf life given from the date of irradiation processing?
Is the supplier provided shelf life long enough to support desired product application?
Is the component shelf life and expiration date traceable?