The Media COA: A Critical Component of the USP <797> Standard

If You Didn’t Document It, Did It Really Happen? 

The 2022 revisions to USP <797> place an increased emphasis on the documentation of standard operating procedures (SOPs), including personnel training, sampling protocols, environmental maintenance, and more. In the event of an audit or adverse event, accurate and thorough record-keeping serves as evidence that processes and procedures are consistently followed.  

This last point cannot be overemphasized. A compounding pharmacy can follow every other element of USP <797> to the letter, but if their documentation practices aren’t up to snuff, they can quickly find themselves in hot water. Without proper documentation, they have no way to prove they followed defined safety protocols or that these protocols were sufficient, and investigators aren’t known for giving pharmacies the benefit of the doubt. 

In this post, I focus on a critical piece of documentation that can get overlooked: the Certificate of Analysis (COA) that accompanies your growth media devices. (agar media devices, tryptic soy bags, etc.) Like the media itself, the COA requires proper handling to ensure compliance with the standard and defensible results. We touched on some of the points made in this post in our recent webinar: The Complete Picture: A Contextual Bridge Between USP <797> & <800>. 

What is a COA? 

The COA is a document provided by suppliers of raw materials and components, certifying the quality and purity of the materials or product. For compounding pharmacies, the COA provides evidence that the materials used in sampling or sterile compounding support patient safety and product efficacy. A COA will accompany more than just your growth media, but as this component is so critical to quality assurance, we need to spend some time unpacking it. 

What the USP <797> Standard Says 

One of the reasons the COA gets overlooked is that there isn’t much emphasis on it in the standard itself. Still, the USP <797> standard should form the basis of your quality control program, so let’s review what it says. 

Section 2.3: If using commercial sterile microbial growth media, a certificate of analysis (COA) must be obtained from the supplier stating that the lot of the growth media will support the growth of microorganisms. 

Section 2.1 has a bit more about COAs, but it refers to components used in the compounding process or in the pharmaceuticals themselves, not the COA for your sterile growth media. 

Nevertheless, the way the USP <797> standard treats COA isn’t that different than how it addresses other aspects of adherence. As we’ve discussed before, USP <797> is a “standard of minimums.” When it comes to growth media devices, a COA must be included stating that the media device will support growth. It’s up to you to define your SOPs for ensuring the vendor can be relied upon and how to document those processes. 

What CETA Says 

When defining a USP <797> quality control program, many pharmacies will also look to the CETA Application Guide: Viable Environmental Monitoring for Sterile Compounding Pharmacies. (current version: CAG-009:2023) Section 8.2 is a little more specific about the types of quality control tests that should be performed by the manufacturer: 

Section 8.2 Media Considerations: Each lot of media requires a certificate of analysis that documents the results of the quality control testing performed (growth promotion, pH, and sterilization). This testing is completed by the manufacturer and is in addition to and prior to the quality control testing that may be performed at the microbiological lab if required or requested. 

CETA also touches on the positive and negative control tests, which we discussed in a post earlier this year: USP 797 FAQs: Positive and Negative Controls. These control tests factor into how you read the COAs accompanying your growth media, so you may want to refresh your understanding if needed.  

Deciphering Your Sterile Growth Media COA 

Let’s look at an actual COA to see what information it should include and why that information matters. This particular COA is for a Tryptic Soy Agar (TSA) media device. COAs for other media devices, such as sterile broth (TSB) bags, may be slightly different. Also, there is plenty of detail on this COA, but we’ll only cover the most critical highlights. 

Product information: At the top of the page is information about the product. As basic as this sounds, always check to ensure the product matches what you ordered and what you received. Mistakes can happen. You’ll also want to verify that the lot number and expiration date on your COA also matches the product you received.  

If there are any mismatches, contact your media vendor right away. To ensure defensible results, you need to make sure you have the correct COA on file. In addition, while we’re not covering media handling procedures in this post, it bears repeating—if the media has expired, do not use it. 

QC Program Information: The next couple of paragraphs in this COA cover the vendor’s internal QC program at a high level. If you aren’t already, it helps to familiarize yourself with the standards mentioned. While not all COAs will contain the same details regarding the vendor’s QC program, this section should be included in every COA. If you have questions or concerns, do not hesitate to contact the vendor or your supplier. 

Instructions for Use (IFU): Notice the IFU statement in the 2nd paragraph. Like many vendors, they have made this information available on their website instead of including it in the packaging. It’s important to periodically download the IFU and check your processes against the manufacturer’s directions. In the event of an adverse event, the IFU gives the vendor an “out” if they can claim their published IFU wasn’t followed. To avoid it being your word against theirs, be sure to document your follow-through on the IFU. 

Positive Growth Test Results: As shown above, Section 2.3 of USP <797> requires the COA to state that this lot of media will support the growth of microorganisms. This is one of those “trust but verify” situations. At a minimum, the vendor should include performance testing results on a representative batch of each media lot.  Again, the pharmacy may choose to also perform positive and negative control tests on each sample submission to ensure growth media viability. 

You may also want to pay attention to which organisms the vendor uses in their positive growth tests. USP <797> does not specify which microorganisms should be used, so it is up to the manufacturer and compounding pharmacy to determine what is appropriate. For guidance, pharmacies may want to look to USP <61>. This standard became effective on May 1, 2025, and covers microbial enumeration tests. The five microorganisms in our sample COA are acceptable per USP <61> for growth promotion testing and should result in a statistically accurate result when testing TSA plates. 

That said, different media devices may be more suitable for some microorganisms than others. The TSA medium shown above is a general-purpose media used for analyzing both bacteria and fungi.  Conversely, Sabouraud Dextrose Agar (SDA) was specifically developed for cultivating fungi, particularly dermatophytes, and has a lower pH (6.9) with high carbohydrate content that promotes fungal growth while suppressing bacterial growth. You are not likely to see Pseudomonas aeruginosa growth on an SDA plate no matter how much of the bacterium you use to inoculate the growth media. 

Physical Characteristics: Before shipping, vendors should perform a physical inspection of the media sleeve to ensure the media has not been damaged. Compounding pharmacies should do the same when receiving each lot and sleeve of media. At a minimum, the appearance, consistency, and fill noted on the COA should match what you receive. You do not need to open the media to check consistency. Growth media with a firm consistency will not behave like Jell-O®, sliding around and changing shape inside the device. The decision to sacrifice a device to test the pH is yours to make. Like all things USP <797>, the choice should be made based on risk. 

USP <797> Documentation Best Practices: COA 

When receiving a shipment of media, a best practice is to keep a log of the physical inspection, noting the vendor, lot number, shipment, and other pertinent details. The log should be signed by the inspector. Conduct periodic inspections of your receiving processes to verify they are being followed. It’s very easy for staff to get busy and forget to download or file the COA as outlined in your SOPs. 

Some vendors may include a hard copy of the COA with the shipment. I always recommend scanning the document and filing the physical copy. That way, you have a backup of both. If the vendor provides the COA online, download a copy to your system. Depending on how good your computer system backup processes are – or aren’t – you may also want to print a hard copy for easy reference.  

Lastly, I often get asked how long physical copies of COA should be kept. While compounded pharmaceuticals have a relatively short shelf life, you’ll want to keep your COAs well beyond that. The statute of limitations for pharmaceutical-related injuries due to negligence can vary by jurisdiction, but it can extend for several years after the discovery of the injury.  

We’d Love to Hear from You! 

If you have questions on COAs or any other aspect of USP <797> compliance, feel free to reach out to us. USP <797> can be complex, so in addition to performing laboratory analysis of samples, we spend a lot of time answering client questions. Contact Pace®