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PRP. Exosomes. Secretomes.
These words are increasingly used in hair restoration and aesthetic medicine, often as though they describe different versions of the same treatment.
They don't.
PRP comes from your own blood.
Exosomes are tiny packages released by cells that carry biological signals.
A secretome is the much broader collection of substances released by cells, which can include growth factors, proteins, cytokines and extracellular vesicles such as exosomes.
At FORM Face + Body, we use technologies involving all three concepts in selected patients. But I think it is important to distinguish exciting biology from proven clinical benefit.
The questions I care about are simple:
What are we actually using?
What evidence supports it?
What are we trying to accomplish?
And how confident are we that it will actually improve the outcome?
PRP stands for platelet-rich plasma.
We draw a small amount of your blood and process it in a centrifuge to create a plasma preparation containing a higher concentration of platelets.
Platelets contain growth factors and signalling molecules involved in tissue repair.
PRP has been studied for many uses, including androgenetic hair loss.
Of PRP, exosomes and secretomes, PRP currently has the largest body of human clinical evidence for hair loss.
A 2025 systematic review and meta-analysis included 43 randomized controlled trials and 1,877 patients. Overall, the evidence supported an improvement in hair density with some PRP protocols. [1]
Other systematic reviews have reached similar conclusions.
But there is a catch.
PRP studies are remarkably inconsistent.
And there are good reasons for that.
I sometimes describe this more casually as your protoplasm and the person holding the needle.
First, PRP comes from you.
Your platelet concentration is not identical to someone else's.
Your growth-factor concentrations are not necessarily identical.
The final preparation can also change depending on the centrifuge, number of spins, activation technique, platelet concentration and amount of white blood cells included.
So two treatments both called “PRP” may not contain the same biological product.
The second issue is delivery.
PRP for hair loss is generally injected manually throughout the scalp.
That means depth matters.
Spacing matters.
The amount injected at each location matters.
The area covered matters.
And the number and timing of treatments matter.
This creates another source of variability.
A 2024 systematic review found encouraging results for PRP in androgenetic alopecia but emphasized that inconsistent preparation and treatment protocols, small studies and variable study quality make the literature difficult to compare. [2]
That is one reason one clinic's PRP treatment may not be equivalent to another clinic's PRP treatment.
When we want to add a procedure-based treatment to a hair-loss program, we frequently use Alma TED.
TED uses low-frequency ultrasound and acoustic pressure to help deliver a topical formulation through the scalp without repeated needle injections.
There are two things I like about this approach.
First, we can use a defined formulation rather than relying entirely on the variable biology of an individual patient's plasma.
Second, the device gives us a more standardized method of delivering that formulation across a defined treatment area.
In other words, we reduce two important sources of PRP variability:
what is being delivered and how it is being delivered.
That does not mean clinical trials have proven TED is superior to PRP.
They haven't.
PRP currently has substantially more published clinical evidence.
Our preference for TED in selected patients is based on standardization and reproducibility, not a claim of proven superiority.
Cells communicate with one another.
One of the ways they do this is by releasing microscopic membrane-bound packages called extracellular vesicles.
Exosomes are one type of extracellular vesicle.
They can carry proteins, lipids, RNA and other signalling molecules from one cell to another.
That makes them biologically fascinating.
Laboratory research suggests extracellular vesicles may influence inflammation, blood-vessel formation, wound healing and pathways involved in hair growth.
But there is a very important distinction:
Showing that an exosome changes cell behaviour in a laboratory is not the same as proving that an exosome treatment regrows hair or rejuvenates skin in a patient.
That clinical evidence still needs to be generated.
At FORM, we use Meta Cell Technology, or MCT, in selected autologous plasma protocols.
MCT does not simply hand us a bottle of manufactured exosomes.
Instead, it applies controlled light and temperature conditions to the patient's own PRP or plasma.
The technology is designed to alter platelet activity and encourage release of growth factors and extracellular vesicles, including exosomes.
So I think the most accurate way to describe it is as photothermally conditioned autologous PRP or plasma.
A 2026 randomized split-face trial compared MCT-conditioned PRP with standard PRP in 28 patients undergoing facial rejuvenation. Some wrinkle measurements favoured the MCT-treated side, while pigmentation, redness and skin mechanical measurements were similar between treatments. [3]
That is interesting.
But it was a small facial-rejuvenation study.
It does not prove that MCT improves hair growth.
And it does not prove that it increases hair-transplant graft survival.
Those questions need to be studied directly.
A hair follicle is under stress from the moment it is removed from the donor scalp until it is implanted into its new location.
Our job during that period is to protect it.
At FORM, we use MCT-conditioned autologous preparations as part of our follicle-soaking protocol during hair transplantation.
The rationale is to provide a supportive biological environment while the grafts are outside the body.
But I am very careful about how I describe that.
The most important determinants of graft survival remain careful harvesting, limited time outside the body, appropriate storage, gentle handling and precise implantation.
The MCT preparation is an adjunct.
At present, we do not have high-quality human transplantation trials showing how much additional graft survival, if any, this strategy produces.
Interesting mechanism?
Yes.
Proven improvement in graft survival?
Not yet.
A secretome is broader than an exosome.
Cells release many different substances into their surrounding environment.
These can include:
The whole collection is referred to as the secretome.
You may also hear the term conditioned media, which refers to the fluid in which cells have been grown and into which they release these substances.
So exosomes can be part of a secretome.
But an exosome and a secretome are not the same thing.
There is no single substance called “secretome.”
The final product depends on the cells that produced it.
It also depends on how those cells were grown, how long they were cultured, how the material was collected and processed, and what was preserved in the final preparation.
That means evidence from one secretome product cannot automatically be applied to another.
This is similar to the PRP problem.
The category name alone does not tell you exactly what is in the vial.
At FORM, one secretome technology we use in selected treatment plans is Acorn Biolabs YOU™ Secretome.
It is personalized.
Hair follicles are collected from the patient. Cells derived from those follicles are cultured, and the substances released by those cells are collected into a cell-free preparation. [4]
That means the final preparation does not contain living stem cells.
It contains substances released by the patient's cells.
That distinction is important.
This is where marketing and evidence need to be separated carefully.
A 2026 publication from Acorn-associated researchers characterized cells obtained from plucked hair follicles and analyzed the secretome they produced.
Researchers identified multiple signalling molecules and extracellular vesicles and demonstrated wound-healing activity in laboratory experiments. [5]
That establishes interesting biology.
It does not establish how much hair a patient will grow.
It does not prove that skin heals faster after treatment.
And it does not establish that the product works better than PRP, minoxidil, TED or another treatment.
Clinical research is underway to answer some of those questions.
Acorn currently has controlled studies examining its secretome for androgenetic alopecia and facial skin quality, along with an observational study evaluating topical secretome use alongside aesthetic procedures. [6]
That is exactly the research I want to see.
But until those results are available, the treatment should be described as promising and emerging, not proven.
In our hair-restoration program, secretome-based products may be used as an adjunct in selected treatment plans.
We may also incorporate a secretome formulation into a TED-based protocol when appropriate.
The appeal is that we can combine a defined clinical process with a cell-derived signalling product rather than relying exclusively on the biological variability of PRP.
Secretome-based products may also have a role around selected skin procedures.
But this is where the Canadian regulatory environment becomes particularly important.
The exact product, the intended use and the route of application all matter.
Health Canada issued final guidance in April 2026 addressing topical products containing:
Health Canada's position is not that every exosome or secretome product belongs to one regulatory category.
A product may be regulated as a cosmetic or a drug, depending on its composition, what it is claimed to do and how it is intended to be used.
For a product to fit the cosmetic category, its intended action generally needs to remain at the surface rather than depend on meaningful absorption through the skin.
Health Canada specifically states that a product represented for administration in a way that facilitates penetration through the skin, including microneedling, is not consistent with ordinary cosmetic use.
Injected products are also not cosmetics.
And a product promoted to treat hair loss or modify a biological function may meet the definition of a drug.
That does not mean every clinical use is prohibited.
It means the regulatory status needs to be assessed for the specific product, claim and route of administration.
This distinction is particularly important.
Cosmetic companies notify Health Canada when products are sold as cosmetics.
A cosmetic notification does not mean Health Canada has reviewed the product and determined that it is effective.
It is not the same thing as drug approval.
Similarly, participation in a clinical trial does not mean a product has been approved for general therapeutic use.
So if someone tells you an exosome or secretome product is “Health Canada approved,” the next question should be:
Approved as what, for what purpose, and by what route?
That is a much more useful question.
At the moment, the answer is PRP.
PRP has the largest clinical literature supporting a potential benefit for androgenetic hair loss.
Its main weakness is inconsistency in both preparation and delivery.
Exosomes have very interesting biological mechanisms, but the clinical literature is much earlier.
Secretomes are equally interesting because they contain a broader collection of cellular signals, but products vary substantially and high-quality clinical studies remain limited.
That hierarchy may change.
Medicine evolves.
But new does not automatically mean better.
I am cautious with this term.
It is an appealing word.
It can also imply much more than the evidence actually demonstrates.
A treatment may increase a signalling protein.
It may alter inflammation.
It may influence a follicle in the laboratory.
It may improve hair density modestly.
Those are all legitimate findings.
But they are not automatically evidence that we have “regenerated” a younger scalp or skin.
A biological finding and a meaningful clinical result are not the same thing.
At FORM Face + Body in Toronto, diagnosis still comes first.
If you are losing hair, I first want to know why.
If you have androgenetic alopecia, established medical treatments such as minoxidil and DHT-blocking therapy remain important parts of the discussion when appropriate.
PRP, TED, MCT-conditioned preparations, exosomes and secretomes are not substitutes for making the correct diagnosis.
They are tools.
We use those tools when the biology makes sense, when the evidence is reasonable and when the potential benefit justifies adding the treatment.
And when the evidence is still emerging, I think patients deserve to hear that too.
Promising is not the same as proven.
That distinction is especially important in regenerative medicine, where the science is genuinely exciting but the marketing can sometimes move faster than the evidence.
PRP, extracellular-vesicle and secretome-based treatments have different evidence bases and regulatory classifications. The status of individual products and permitted uses can change. Specific treatment recommendations require individual assessment. This article is educational and is not a substitute for personal medical advice.
