United States Food and Drug Administration and Department of Defense shelf-life extension program of pharmaceutical products: progress and promise.

The Department of Defense (DoD)-United States Food and Drug Administration (FDA) shelf-life extension program (SLEP) was established in 1986 through an intra-agency agreement between the DoD and the FDA to extend the shelf life of product nearing expiry. During the early stages of development, special attention was paid to program operation, labeling requirements, and the cost benefits associated with this program. In addition to the substantial cost benefits, the program also provides the FDA's Center for Drug Evaluation and Research with significant scientific understanding and pharmaceutical resource. As a result of this unique resource, numerous regulatory research opportunities to improve public health present themselves from this distinctive scientific database, which includes examples of products shelf life, their long-term stability issues, and various physical and chemical tests to identify such failures. The database also serves as a scientific resource for mechanistic understanding and identification of test failures leading to the development of new formulations or more robust packaging. It has been recognized that SLEP is very important in maintaining both national security and public welfare by confirming that the stockpiled pharmaceutical products meet quality standards after the "expiration date" assigned by the sponsor. SLEP research is an example of regulatory science that is needed to best ensure product performance past the original shelf life. The objective of this article is to provide a brief history and background and most importantly the public health benefits of the SLEP.

Stability profiles of drug products extended beyond labeled expiration dates.

The American Medical Association has questioned whether expiration dating markedly underestimates the actual shelf life of drug products. Results from the shelf life extension program (SLEP) have been evaluated to provide extensive data to address this issue. The SLEP has been administered by the Food and Drug Administration for the United States Department of Defense (DOD) for 20 years. This program probably contains the most extensive source of pharmaceutical stability data extant. This report summarizes extended stability profiles for 122 different drug products (3,005 different lots). The drug products were categorized into five groups based on incidence of initial extension failures and termination failures (extended lot eventually failed upon re-testing). Based on testing and stability assessment, 88% of the lots were extended at least 1 year beyond their original expiration date for an average extension of 66 months, but the additional stability period was highly variable. The SLEP data supports the assertion that many drug products, if properly stored, can be extended past the expiration date. Due to the lot-to-lot variability, the stability and quality of extended drug products can only be assured by periodic testing and systematic evaluation of each lot.