FDA Registered 503B Outsourcing Facility

What Is a 503B Manufactured Drug and Why Is It Better?

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503B outsourcing facilities play an essential part in providing high-quality veterinary healthcare. However, the role of these facilities and the benefits they offer can be unclear or confusing based on their technical definitions.

To help you do what you do best – care for patients at the highest level possible – we’re breaking down the basics of compounding pharmacies and compounded medications for you. Then we’ll explore what sets 503B outsourcing facilities apart. (If you’ve got the basics down, you can jump ahead to find out more about 503B and what makes 503B-compounded drugs different).

Quick Read Key Takeaways:

  • Compounding pharmacies are used to produce drugs that meet specific needs for animals.
  • Traditional compounding pharmacies are known as 503A pharmacies, outsourcing facilities refer to 503B manufacturers.
  • Compounded medications are manufactured according to FDA guidelines and modifications to drugs such as mixing or changing ingredients are done per FDA regulations.
  • The safety of compounded medications can vary depending on if they are produced in a 503A pharmacy or manufactured by a 503B outsourcer.
    • 503B outsourcing facilities require and confirm medications purity,
      stability, and sterility.

For another great read that outlines 503A vs 503B? Read our comparison blog

The Basics—Compounding Pharmacies and Compounded Medications

What is a compounding pharmacy?

A compounding pharmacy creates drugs to meet the unique needs of patients who cannot be treated with commercially available medication. In veterinary healthcare, since most medications are created for human use, compounding pharmacies are necessary for producing drugs that meet the specific needs of animals. There are two types of compounding pharmacies:

  • Traditional compounding pharmacies, also known as 503A pharmacies, can compound medications only on a prescription-basis for specific patients, and are probably most familiar to veterinarians.
  • 503B outsourcing facilities manufacture large batches of traditionally compounded medications for bulk purchase by veterinary hospitals and clinics. If a 503A pharmacy has a 503B partner company, individual patient scripts can also be filled with the 503B-manufactured version of the prescribed drug.

What is a compounded medication?

A compounded medication for dogs, cats, and other types of animals is a modified formulation of an FDA-approved, commercially available drug. Modifications must be done by a compounding pharmacist or a veterinarian and can include concentrating, diluting, mixing, and/or changing ingredients to make a medication that fits the needs of a particular patient. Frequently, commercially available drugs do not come in concentrations that are safe for animals or in needed dosage forms or flavors that are palatable, so compounded medications produced by traditional 503A compounding pharmacies and 503B outsourcing facilities play a vital role in veterinary healthcare. Examples of modifications include:

  • Adding flavoring.
  • Changing the dosage form of the medication to accommodate patients who have difficulty swallowing pills or whose GI tracts can’t tolerate oral medication.
  • Tailoring the strength or concentration of the drug based on an animal’s size, species, or other characteristics.
  • Mixing two injectable medications so they can be administered using the same syringe.
  • Changing the drug formulation to remove nonessential ingredients to which the patient is allergic.

What type of medication can be compounded for animal use?

If there aren’t any commercially available medication options that are appropriate for an animal patient’s particular needs, then the best treatment option may be to use a compounded medication. Medications can be compounded for animal use to treat a wide range of ailments including cancer, bacterial and parasitic infections, hyperthyroidism, autoimmune disorders, and allergies, Veterinary medications can be compounded in many forms including:

  • Transdermal/topical medications
  • Oral tablets, chews, and capsules
  • Liquid solutions
  • Injectables
  • Ophthalmic drops and ointments

Are compounded medications safe?

Because veterinarians treat a wide variety of species whose needs differ considerably, compounded medications are crucial to providing effective veterinary treatment. However, the safety and efficacy of these medications can vary, so choosing a veterinary compounding pharmacy with a track record of quality is important. One factor to consider is whether the compounder is a traditional 503A compounding pharmacy or a 503B outsourcing facility. While a 503A veterinary compounding pharmacy has to comply with the standards established by the United States Pharmacopeia (USP) that are regulated at the state level, 503B outsourcing facilities are regulated at the federal level by the FDA and must comply with the incredibly stringent testing requirements set forth by the FDA’s Current Good Manufacturing Practices (cGMP). cGMP regulations require that testing be done on every batch of compounded medication produced by a 503B outsourcing facility to confirm the medication’s:

  • Purity or potency (i.e., that it contains the desired amount of active drug).
  • Stability until its expiration date.
  • Sterility (if applicable).
Common FAQs about 503B dispensing.

503A vs 503B-What You Need to Know

Now that we’ve covered the basics, let’s take a look at what 503B means and what sets 503B outsourcing facilities apart. (Hint: the drugs they manufacture are important in making sure your patients receive the highest quality care.)

How does the FDA define 503B manufacturing?

FDA 503B refers to Section 503B of the Food, Drug, and Cosmetic Act (FD&C Act). Section 503B was added to the FD&C Act in 2013 as concerns about the safety and quality of compounded medications increased. Section 503B allowed for the development of a new type of drug compounding facility called 503B outsourcing facilities. Registration as a 503B outsourcing facility is optional, so traditional 503A compounding pharmacies, which provide individual patients with customized medications on a prescription-basis, are not required to register as a 503B facility. However, if a compounding facility wants the ability to dispense larger quantities of compounded medications to veterinary healthcare facilities for office use without the need for a prescription, 503B registration and compliance are required. 

What is the difference between 503A and 503B?

When deciding whether to use a traditional 503A compounding pharmacy or a 503B outsourcing facility, there are several key differences to keep in mind. 503A traditional compounding pharmacies must follow state board of pharmacy regulations and comply with USP standards <795> and <797> for compounding nonsterile and sterile medications. Although some states do allow dispensing of veterinary products for office use, most traditional neighborhood compounding pharmacies are limited to dispensing medications based on patient-specific prescriptions.

While 503B outsourcing facilities are licensed or registered by state regulators, they additionally have to comply with the FDA’s more rigorous cGMP regulations (21 CFR Part 210 and 211)—the same regulations as major human pharmaceutical manufacturers. Because 503B outsourcing facilities are overseen by the FDA and held to more stringent quality standards, they can manufacture large batches of compounded medications for bulk sale to veterinary clinics and hospitals, referred to as “outsourcing,” and these medications can then be kept on-hand by veterinary clinics and hospitals for office use. The larger batch sizes cut down on production expenses, resulting in cost savings for veterinary practices and their clients and inventory management efficiencies for clinics and hospitals.

What veterinarians say about having a 503B partner: 

"As a veterinarian, I often rely on compounding medications for my clients. Epicur Pharma is an easy choice for me. Their quality control following Current Good Manufacturing Practices and their transparency about independently certified assays give me confidence my patients will receive the exact medication and strength as prescribed. I know I can rely on their quality and efficiency for both my patients and my own pet."

What is cGMP compliance?

Compliance with the FDA’s cGMP standards is another key differentiator between traditional 503A compounding pharmacies and 503B outsourcing facilities. To be compliant with cGMP regulations, 503B outsourcing facilities must meet minimum standards set by the FDA for the facilities, methods, and controls used during drug manufacturing to ensure quality and safety. Standards that must be monitored and maintained apply to a wide range of areas that impact 503B functioning including:

  • Facility design
  • Personnel training
  • Equipment
  • Supplier qualifications
  • Documentation
  • Tracking and traceability for every step of the compounding process
Finished Product Testing: Potency, Sterility, Endotoxins

cGMP compliance requires 503B outsourcing facilities to conduct multiple batch-specific release tests before dispensing the compounded medications produced. Every batch of finished product undergoes the following tests:

  • Potency testing to confirm the delivered dose meets the label’s claims.
  • Sterility testing for all sterile compounded medications to ensure there are no contaminating microorganisms that would impact safety.
  • Endotoxin testing, for all sterile preparations that are injectables, to ensure harmful bacterial endotoxins are not present.

Traditional 503A compounding pharmacies do not have to test for potency and only need to conduct sterility and endotoxin tests if a batch is 25 units or larger. As a result, while there are 503A compounding pharmacies that consistently meet high quality standards, significant disparities can exist. 

Stability Testing

To meet cGMP standards, 503B outsourcing facilities also must have a stability testing program in place that adheres to the International Council for Harmonisation (ICH) guideline Q1A(R2) to determine the length of time the strength and safety of a compounded medication can be guaranteed and recommended storage conditions. Stability testing enables 503B outsourcing facilities to assign an expiration date to their compounded medications.

In contrast, the medications compounded by traditional 503A compounding pharmacies are given a beyond-use date (BUD). While some 503A compounding pharmacies assign a BUD based on testing, USP guidelines do not mandate that these pharmacies have a stability testing program in place.

Read our White Paper:
The Importance of cGMP (503B) Compounded Drugs: 

Often times the BUD is determined based primarily on:

  • Pharmaceutical company recommendations,
  • Clinical literature, and/or
  • Limits set by the USP.

Accuracy can vary greatly depending on the 503A compounding pharmacy’s processes and the quality of its staff training program.

The benefits of 503B outsourcing facilities’ stability testing programs include:

  • Assurance that a compounded medication will be safe and retain its potency during patient use.
  • Increased convenience for veterinary hospitals and clinics wanting to keep frequently needed compound medications in stock since expiration dates typically exceed BUDs.
Equipment Validation

Precision and accuracy are critical to the production of compounded medications. If a balance used to weigh ingredients is even slightly off or if a mixer isn’t evenly combining ingredients, for example, it can have an impact on a medication’s quality and safety. At 503B outsourcing facilities, all equipment used in the key stages of production must be routinely validated to confirm proper functioning. Additionally, while 503A compounding pharmacies regularly perform minor calibrations on equipment, 503B outsourcing facilities routinely perform full calibrations that meet or exceed manufacturer specifications.      

Environmental Monitoring

Environmental monitoring is vital to avoiding microbial contamination when compounding sterile medications. In 503A compounding pharmacies, environmental monitoring needs to be done every six months, while in 503B outsourcing facilities, assessment of air and surface microbial levels in key compounding areas is required for every batch produced. The ongoing assessment of microbial levels ensures potentially unsafe products are not dispensed and enables the 503B outsourcing facility to quickly identify the source of contamination.    

Traditional 503A compounding pharmacies and 503B outsourcing facilities each serve important functions in veterinary healthcare. 503B outsourcing facilities fill a key gap when safe, high-quality traditionally compounded medications are needed for office use.

Contact us today to learn more about partnering with Epicur.

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