How to navigate the transition from beyond-use dates to expiration dates
Traditionally, veterinary hospitals and clinics use neighborhood or national 503A compounding pharmacies to fill prescriptions for compounded medications. These medications are labeled with a beyond-use date (BUD). With the growing number of 503B manufactured veterinary medicines available, you may notice these products are labeled with an expiration date instead. Understanding this seemingly small difference can make a significant difference to your standard of care and your practice’s bottom line.
BUDs for compounded sterile and nonsterile preparations from 503A pharmacies are never dated longer than 6 months, and limited documentation is provided to prove otherwise. United States Pharmacopeia (USP) new guidelines will limit these dates even further.1
You’ll notice expiration dates for 503B manufactured medicines typically offer a far longer shelf life, ranging from months to years. The expiration date is determined after robust stability testing that is required by the FDA’s current Good Manufacturing Practices regulations. This longer shelf life and comprehensive stability testing offer veterinary practices the following:
Inventory waste due to expired medicines can represent 1.5% to 2% of your total revenue. By stocking 503B manufactured medicines with longer shelf lives, veterinary practices can reduce guesswork, improve outcomes, and boost profit margins.
Expiration dates are established after robust stability testing, which includes multiple product lot analyses of several different types of stability: chemical (potency and chemical integrity of active ingredients), microbiological, physical (palatability, appearance, solubility, viscosity), therapeutic, and toxicological.
Although 503B manufacturers have established repeatable testing protocols to confirm stability at 3, 6, 9, and 12 or more months, 503A pharmacies typically lack the resources to do so.
In place of stability testing to establish an expiration date, these pharmacies determine a BUD, an educated guess based on manufacturer recommendations for the reference drug, published clinical literature, and limits set by the USP. Variations in formulation, packaging, and storage can alter a product’s stability.
Stability testing ensures the product’s safety, quality, and efficacy. It plays an important role in safeguarding patient well-being. Products that exceed their shelf life or those that have incorrectly assigned BUDs can cause a variety of problems that affect patient health, including degradation or increased concentration of the active ingredient; contamination during distribution or storage; changes in the drug’s bioavailability, altering the rate and amount absorbed by the patient; and development of toxic byproducts over time.
For patients who require a highly customized preparation, it’s important to understand the difference between BUDs and expiration dates, as well as the trade-offs involved. With the growing availability of 503B medicines with rigorous stability testing standards, expiration dates offer veterinary practitioners far greater confidence in a medication’s stability and help reduce inventory waste. Products with expiration dates have quality built in.
Melissa King, PharmD, is a pharmacist and operations leader at Epicur Pharma. She oversees manufacturing and distribution operations in accordance with current Good Manufacturing Practice (cGMP) regulations. cGMPs are integral to 503B drug manufacturing, and King is working to raise the bar in veterinary medicine. King earned her PharmD from the University of the Sciences in Philadelphia, Pennsylvania.
Reference
USP compounding standards and beyond-use dates (BUDs). United States Pharmacopeia. June 3, 2019. Accessed September 1, 2022. https://www.usp.org/sites/default/files/usp/document/ our-work/compounding/usp-bud-factsheet.pdf