Two vials labeled “exosomes” can contain almost nothing in common. A 2026 review in Advanced Science argues that the fastest way to move the field forward is not another animal study; it is agreeing on what to measure, how to measure it, and which numbers have to travel with every batch. Read as a checklist, it is close to a specification for what an exosome certificate of analysis should contain.
The Review That Reframed the Problem
In April 2026, a group led by David J. Lundy at Taipei Medical University, working with colleagues at the University of Washington, UCLA, Georgia Tech, Stanford and the University of Tsukuba, published “Beyond Extracellular Vesicle (EV) Hype: Practical Solutions and Remaining Hurdles in EV Research, Manufacturing, and Clinical Translation.”
The paper is unusual in tone. Most reviews of exosomes and extracellular vesicles catalog what the vesicles might do. This one focuses on what the field can currently prove, and it is blunt about the gap. The authors conclude that translational progress is constrained by three things: an incomplete mechanistic understanding, a lack of standardized measurements, and inconsistency in how regulators classify these products.
Their proposed fix is a shift in mindset. Exosome work needs to move from descriptive studies into a reproducible, quantitative measurement science. In plain terms: stop describing, start counting, and publish the counts.
Two Parallel Worlds, One Word
The review draws a line that anyone shopping for exosome products should keep in mind. Extracellular vesicles currently occupy two separate universes that happen to share vocabulary.
The first is the regulated biologic drug pathway, where products advance through Investigational New Drug applications, defined manufacturing controls and randomized clinical trials. The second is a diffuse market of cosmetic and wellness offerings promoting “exosomes” for conditions as varied as aging, autism, diabetes, osteoarthritis and allergies.
The word on the label is identical. The evidence, the manufacturing controls and the documentation behind it are not. Regulatory treatment differs sharply by country as well: South Korea issued extracellular vesicle specific guidelines in 2018 and Taiwan followed in 2025, while Japan’s regenerative medicine safety law did not originally cover these products at all.
Why a Particle Count Is Not a Dose
The most useful section of the paper explains, with uncomfortable specificity, why the single number most often quoted on an exosome label carries less information than buyers assume.
Particle counters do not know what a particle is
Nanoparticle tracking analysis, the most common method behind a stated particle count, measures light scattered by objects of a certain size. It cannot reliably distinguish a vesicle from a protein aggregate of similar dimensions. A high count is compatible with a highly pure preparation and with a poorly purified one.
Blood-derived preparations are mostly not vesicles
The review cites an estimate that of all particles in the 10 to 1000 nanometer range in blood, roughly 99.9998 percent are lipoproteins and about 0.0002 percent are extracellular vesicles. Those co-isolated particles are not necessarily inert; some carry microRNA cargo with real biological effects. They change apparent yield, measured dose and functional readouts all at once.
Identity markers are not uniformly present
The tetraspanins CD9, CD63 and CD81 are the standard identity markers for exosomes. Work cited in the review found that these markers were not uniformly expressed across preparations from human serum, cultured mesenchymal stem cells and a cancer cell line. Testing for one marker in bulk tells you the population contains it somewhere. It does not tell you what fraction of your vesicles carry it.
The authors’ recommendation follows directly: use orthogonal analyses rather than a single assay, quantify the co-isolates instead of leaving them unmeasured, and treat purity as a number rather than an adjective.
The Four Numbers an Exosome Certificate of Analysis Should Carry
Read alongside the MISEV2023 guidelines from the International Society for Extracellular Vesicles, the review points toward a short list of attributes that should be established for any preparation before it is used. This is essentially what a serious exosome certificate of analysis exists to document.
- Identity. Source material, cell type and passage, isolation method, and the molecular markers actually detected. The review argues identity should be defined operationally, by how the product was made, not by the name on the vial.
- Purity. Quantified co-isolates such as albumin and apolipoproteins, not a qualitative claim. Purity that is not measured is not purity.
- Quantity. Particle concentration, ideally cross-checked by a second method that resolves vesicles from similarly sized non-vesicular particles.
- Potency. A functional assay tied to the intended biological effect, repeated after storage. The paper treats container type, temperature, freeze-thaw exposure and storage duration as critical variables, and calls for re-testing after storage to confirm lot integrity and comparability between batches.
That last point deserves emphasis. A certificate generated at manufacture describes the product at manufacture; stability-indicating retesting is what connects it to the vial in front of you. These are the questions our quality standards are built to answer, and they extend the argument we covered in the exosome standardization crisis from the market side to the bench side.
Where Clinical Programs Actually Stand
The review is not dismissive of clinical progress. It is specific about where that progress sits.
ExoFlo, a bone marrow mesenchymal stem cell derived vesicle product, was the first widely publicized exosome therapeutic to reach clinical testing, in an open-label study of 24 patients with severe COVID-19 associated respiratory failure. The authors note that early work drew criticism for incomplete reporting of dose, purity and critical quality attributes, while still crediting it as a genuine milestone. A multicenter Phase 3 trial, EXTINGUISH-ARDS, is now underway with results expected in 2027.
The second program highlighted is RION’s Purified Exosome Product, a shelf-stable lyophilized platelet-derived preparation with a reported room-temperature shelf life of 24 months. A Phase 2 multicenter trial of topical application in diabetic foot ulcers, with 59 participants, has completed enrollment. In January 2026 the FDA granted Fast Track designation in that indication, with a pivotal Phase 3 trial planned.
Both examples make the same point. The programs that advanced are the ones that could document what was in the vial, which is also the lens worth applying to the wider research literature.
What This Means If You Are Sourcing Product
None of this argues that exosomes do not work. It argues that “exosomes” is not a specification, and that the difference between two suppliers is usually invisible until you ask for documents.
Practically, the review supports a short due diligence habit. Ask for a lot-specific certificate rather than a representative one. Ask which methods produced each number, and whether any attribute was confirmed by a second, independent method. Ask what the potency assay measures, whether it was repeated after storage, and what happens to the product if the cold chain breaks.
The same logic applies whether you are evaluating stem cell products, peptides or vesicle preparations. A supplier who can answer those questions in writing has done the work; one who cannot has not, whatever the marketing says. Our approach to sourcing and characterization exists because that distinction is the whole ballgame.
Frequently Asked Questions
Are there any FDA-approved exosome products in 2026?
No. As of August 2026 there is no FDA-approved therapeutic exosome product. Multiple candidates hold Investigational New Drug clearance and are in Phase 1 through Phase 3 trials, and one has Fast Track designation, but approval has not been granted. Any product marketed as an approved exosome treatment is misrepresenting its status.
What does a particle count on an exosome label actually tell me?
It tells you how many objects of a given size range were detected, usually by nanoparticle tracking analysis. It does not confirm those objects are vesicles, that they carry exosome identity markers, or that they are biologically active. A particle count is one input among four, alongside identity, purity and potency, not a summary of product quality.
What are MISEV guidelines and why do they matter to a clinic?
MISEV stands for Minimal Information for Studies of Extracellular Vesicles, published by the International Society for Extracellular Vesicles and most recently updated as MISEV2023. It defines the minimum characterization and reporting a study needs to be interpretable. For a clinic, it is a useful benchmark: a supplier whose documentation maps onto MISEV categories is speaking the same language as the peer-reviewed literature.
How can I compare two suppliers whose labels look identical?
Request lot-specific certificates from both and compare them attribute by attribute: source and cell type, isolation method, particle concentration and the method used, identity markers detected, quantified co-isolates or purity metrics, sterility and endotoxin, potency assay and result, and storage conditions. Differences that marketing hides tend to show up immediately in that side-by-side.
Ask Us the Hard Questions
OmniGenix supplies characterized exosome, stem cell and peptide products to licensed practitioners, with lot-specific certificates of analysis on every order. We do not treat patients directly.
This article is for educational purposes and describes published research. It is not medical advice and does not constitute a claim of safety or efficacy for any product. OmniGenix products are supplied to licensed practitioners and are not FDA approved for the treatment of any condition. Source: Lundy DJ, Chau ZL, Chen SY, Fujisawa N, Hill JJ, Hsu BM, Liu JK, Mai KW, Lai JJ. Beyond Extracellular Vesicle (EV) Hype: Practical Solutions and Remaining Hurdles in EV Research, Manufacturing, and Clinical Translation. Advanced Science. 2026;13(26):e21913. doi:10.1002/advs.202521913