Exosomes are one of the fastest-growing product categories in regenerative medicine. They are also one of the least regulated. The FDA has not approved any exosome product for therapeutic use. That means the quality, safety, and documentation of what you purchase rests entirely on the supplier and on your diligence as the buyer.

This is not a theoretical concern. Clinics that purchase exosome material without verifying its quality face three risks: patient adverse events, regulatory exposure, and reputational damage. A single contaminated lot can end a practice. A single FDA enforcement letter can shutter it.

The good news: the documentation that proves quality is available from reputable suppliers. The problem is knowing what to ask for, what it means, and what it does not prove. This guide gives you the twelve questions that separate documented suppliers from undocumented ones.

The Twelve Questions

Documentation and Testing

  1. Does the supplier provide a Certificate of Analysis (COA) for every batch? A COA is the batch-specific document that records what was tested and what the results were. If the supplier cannot produce a COA for the specific batch you are buying, you have no documented evidence of what is in the vial.
  2. Is the COA from an independent third-party laboratory? Internal testing is better than nothing, but it is not independent. A supplier testing their own product has an incentive to report favorable results. An independent lab (Eurofins, Nelson Labs, etc.) has no such incentive. Ask who performed the testing. If the answer is "our in-house lab," that is a yellow flag.
  3. Does the COA include sterility testing (USP <71>)? Sterility testing confirms the absence of bacterial and fungal contamination. USP <71> is the recognized standard. If the COA does not mention USP <71> or an equivalent compendial method, the supplier may not be testing for sterility at all.
  4. Does the COA include endotoxin testing (USP <85>)? Endotoxins are bacterial cell wall fragments that can cause fever, inflammation, and septic shock. USP <85> is the standard test (LAL assay). Endotoxin limits for injectable products are typically <5 EU/kg. If endotoxin is not on the COA, the material may not be safe for injection.

Source and Process

  1. What is the tissue source? Exosomes can be derived from many sources: Wharton's jelly (umbilical cord), amniotic fluid, adipose tissue, bone marrow, dental pulp, and others. The source determines the regenerative potential, the regulatory classification, and the risk profile. Ask specifically: "What tissue are these exosomes derived from?"
  2. What is the donor screening process? Under 21 CFR 1271, tissue donors must be screened for communicable diseases (HIV, hepatitis, syphilis, etc.) and reviewed for risk factors. Ask the supplier for their donor screening protocol. If they cannot describe it, they may not be following it.
  3. Is the material processed in an ISO-classified cleanroom? ISO 5 (Class 100) is the standard for sterile injectable processing. ISO 7 or ISO 8 is acceptable for non-sterile processing but is not adequate for material that will be injected into patients. Ask for the cleanroom classification certificate.
  4. What is the particle count and concentration? Exosome quality is partly defined by particle count (typically reported as particles per milliliter) and concentration. Nanoparticle tracking analysis (NTA) is the standard method. A supplier that does not report particle count may not be measuring it.

Traceability and Claims

  1. Can the supplier provide lot-level traceability? Lot-level traceability means that for any vial you purchase, the supplier can trace it back to the donor, the collection date, the processing batch, and the test results. This is required under 21 CFR 1271.90 for HCT/P establishments. Ask: "If I buy a vial today, can you trace it to the specific donor and batch?"
  2. Does the supplier make therapeutic claims? If a supplier claims their exosomes "treat inflammation," "reduce pain," or "promote healing," they are making therapeutic claims for an unapproved product. This is a regulatory red flag. The supplier is either unaware of the regulatory framework (dangerous) or willing to violate it (more dangerous). Either way, their compliance posture is a leading indicator of their quality posture.
  3. Is the material labeled for its intended use? Exosomes supplied for research use only (RUO) are not intended for human therapeutic use. If you are purchasing RUO-labeled material and using it clinically, you are accepting the regulatory risk. Know what the label says. Know what it means.
  4. What does the supplier not test for? No COA tests for everything. Ask what is not on the panel. Common gaps: mycoplasma testing (bacterial contamination without cell walls), viral screening (beyond the standard donor screening panel), and potency assays (functional activity, not just particle count). A supplier who says "we test for everything" is either lying or does not understand the question.

The principle: Documentation does not guarantee quality. But the absence of documentation guarantees the absence of evidence. You cannot evaluate what has not been measured. A supplier who cannot produce test results is asking you to trust them. In regenerative medicine, trust is not a substitute for data.

What a Good COA Looks Like

A proper Certificate of Analysis from a reputable supplier includes:

If any of these are missing, ask why. Some may not be applicable to every product. But the supplier should be able to explain the gap, not just shrug at it.

Red Flags That Should End the Conversation

The Evaluation Framework

At Genademy, we teach an 8-step framework for regenerative medicine: Science, Evidence, Regulation, Clinical Reasoning, Technique, Safety, Implementation, and Outcomes. Supplier evaluation falls under Step 3 (Regulation) and Step 6 (Safety). The framework is vendor-agnostic. We do not tell you which supplier to buy from. We teach you how to evaluate any supplier.

The framework exists because the market is opaque. Most exosome suppliers provide only internal COAs. Most do not test every batch. Most do not provide lot-level traceability. The supplier that does provide these things stands out, but only if you know to ask for them.

Now you know to ask.

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Frequently Asked Questions

Are exosomes FDA-approved?

No. As of 2026, there are no FDA-approved exosome products for therapeutic use in humans. Exosomes supplied in the US are regulated as biological materials under 21 CFR 1271, but they are not approved as therapeutics. Any supplier claiming FDA approval is misrepresenting their regulatory status.

What is the difference between research use only (RUO) and clinical use?

RUO-labeled material is not intended for human therapeutic use. If you purchase RUO material and use it clinically, you are accepting the regulatory risk. Some suppliers label their material RUO to limit their liability while knowing it will be used clinically. Understand what the label means before you purchase.

How important is particle count?

Particle count tells you how many exosomes (or exosome-sized particles) are in each dose. It is a quantity measure, not a quality measure. A high particle count does not guarantee biological activity. But a low or unreported particle count means you do not know what dose you are delivering.

Should I require mycolpasma testing?

Mycoplasma is a common contaminant in cell culture. It is a bacterium without a cell wall, which means it is not detected by standard sterility tests (USP <71>). If your supplier processes material in cell culture, mycoplasma testing is worth asking about. It is not on every COA, but its absence is worth understanding.