What are exosomes, and what is exosome therapy?

What the word exosome means

The MISEV2023 guideline, published in 2024, says that unless a study shows where inside the cell its particles came from, the study is likely looking at a broad population of extracellular vesicles and not exosomes specifically.[1]

This page uses the term exosomes (extracellular vesicles) for products sold under either name.

Exosome therapy means treatment with products sold as exosomes, which come from different sources, including human stem cells and plants.[2]

How are exosome products made, and what is in them?

The MISEV2023 guideline says that most methods for separating extracellular vesicles also collect other particles that are not vesicles.[1] Particles that are not vesicles may greatly outnumber extracellular vesicles in biological samples, according to the MISEV2023 guideline.[1]

A 2026 scoping review of topical exosomes for skin rejuvenation also looked at the first 20 commercially available products returned by a Google Shopping search for exosomes and found that the products gave minimal information on how the exosomes were isolated or processed, or on shelf life.[2]

In a patient notice published on August 8, 2020, the International Society for Extracellular Vesicles warned people considering unproven exosome therapies: 'You could be exposing yourself to dangerous products containing impurities and pathogens like bacteria or viruses.'[3] In searches of Europe PMC (which includes preprints) and PubMed on October 1, 2026, we found no study that tested exosome products sold on the market for contamination, and no source we read says how often such products are contaminated.

What the research shows, use by use

Results for one exosome product, route or condition do not carry over to a different product, route or condition.

Unless a sentence names its own databases, the searches behind each statement on this page about what we found were run in PubMed, Europe PMC and ClinicalTrials.gov on October 1, 2026.

A systematic review of 25 published clinical trials of cell-derived extracellular vesicles, with a search that ran to September 19, 2024, reported marked differences between the trials, and 7 of the 25 were controlled trials.[4]

FDA's statements about exosome products as a group are in a separate section of this page.

Evidence levels in this table follow our grading key. Established means consistent results from randomized trials or a systematic review of them. Emerging means some controlled human evidence that falls short of Established, such as small, short or single trials or trials funded by a seller. Experimental means no controlled human evidence, only animal, lab or uncontrolled human studies. Evidence against means a controlled trial tested the claim on its main outcome and did not find the effect. No row in this table reaches the Established level.

Exosomes for hair loss

Published research on exosome products for hair loss is at an early stage: it includes small placebo-controlled trials of different products, studies with no comparison group, and lab and animal studies. On October 1, 2026, a ClinicalTrials.gov search for exosome or secretome products in hair loss returned registered trials with a saline or placebo group. None of the records it returned has posted results, and they include NCT06932393, terminated with 16 participants enrolled, and NCT07693244, which is recruiting with 120 planned.[5][6] A Europe PMC search on October 1, 2026 also returned preprints on medRxiv, including PPR1083961 and PPR1317786, of randomized placebo-controlled trials of scalp products made with plant-derived extracellular vesicles, each in 60 healthy adults. Preprints have not been peer reviewed, and we read only the abstracts.[7][8] In a placebo-controlled pilot trial, 24 men with male pattern hair loss were randomized to scalp injections of a plant-extract exosome formulation or saline, 20 were analysed, and by week 16 the men given the formulation had a larger increase in hair count (p = 0.006).[9] The pilot hair trial's paper reported no external funding and no conflicts of interest and thanked a company for supporting the research materials, and a ClinicalTrials.gov record that appears to describe the same trial lists that company as the trial's sponsor.[9][10] The pilot hair trial tested a plant-based formulation, so that trial does not show what exosome products made from human stem cells do for hair.

We found no second trial of the same plant-extract formulation for hair loss in searches of PubMed, Europe PMC and ClinicalTrials.gov on October 1, 2026.

A separate placebo-controlled trial randomized 85 people with pattern hair loss to scalp injections of fat-derived stem cell exosomes or saline, and reported a larger gain in hair density at 12 weeks with the exosomes than with saline (35 compared with 3 hairs per square centimeter, p = 0.001).[11] The paper for the 85-person hair trial does not describe blinding, ethics approval, trial registration, funding or conflicts of interest, and we did not find the paper in PubMed or Europe PMC.

In a double-blind, placebo-controlled pilot study of 39 adults with self-perceived thinning hair, 31 were assigned to apply a human platelet exosome extract serum to the scalp once a day and 8 to apply a placebo serum. A blinded evaluator rated hair density, fullness and scalp coverage as improved more with the platelet serum than with placebo at 3 and 6 months.[12] The platelet serum study was funded in part by an aesthetics company, and five of its eight authors were consultants for that company or declared an ownership interest in it.

A 2025 systematic review of exosomes for hair loss included 11 clinical studies, two of them randomized controlled trials, and described the evidence as limited by differences between studies, small sample sizes and varying follow-up.[13]

Two of the uncontrolled studies of exosome products for hair in people, each with 30 participants, compared hair measurements with those taken before treatment and had no comparison group.[14][15] One of those two studies, which applied an exosome product to the scalp after radiofrequency microneedling, listed the company that sells the product as a collaborator in its trial registration.[16]

A 2026 systematic review of 16 lab and animal studies, most of them in mice, reported that exosomes improved measures of hair growth; lab and animal results do not show an effect in people.[17] A 2026 meta-analysis reported pooled percentage improvements in hair density and thickness, but the percentages are changes from before treatment within treated groups and are not comparisons with a control group.[18]

Exosome products applied after microneedling for skin

Small split-face trials suggest that exosome products applied to the skin after microneedling may improve the look of aging facial skin more than microneedling alone, and a 2026 systematic review of extracellular vesicle treatments for facial rejuvenation rated the certainty of the evidence low or very low.[19][20][21] A 2026 systematic review of extracellular vesicle treatments for facial rejuvenation included 16 studies with 503 participants and rated the certainty of the evidence as low or very low.[19]

The 2026 review of facial rejuvenation studies reported that comparative studies generally favored the areas treated with extracellular vesicles, and judged the risk of bias moderate to critical for most effectiveness outcomes.[19]

In a randomized split-face trial of 28 people, the side of the face treated with a fat-derived stem cell exosome solution plus microneedling scored higher on a global appearance scale than the side treated with saline plus microneedling, 6 weeks after the last of three sessions (p = 0.005).[20] In a split-face study of 6 people, wrinkles improved more at 1 and 3 months on the side where a rose-derived exosome product was applied after needling radiofrequency, and the difference in pores was not significant overall.[21] In a randomized split-face study of 60 adults that was not blinded, wrinkle scores improved more at 12 weeks on the side given a topical extracellular vesicle preparation after radiofrequency microneedling than on the side given radiofrequency microneedling alone.[22]

In searches of PubMed and Europe PMC on October 1, 2026, we found a published split-face trial of an exosome product against platelet-rich plasma (PRP) for photoaged facial skin. It enrolled 15 people and reported no significant difference in overall skin appearance at 6 months between the side of the face treated with the exosome product and the side treated with PRP, both applied after radiofrequency microneedling.[23] The 15-person trial comparing an exosome product with PRP was supported in part by a research grant from the company that sells the exosome product.[23] A Europe PMC search on October 1, 2026 that required no skin word also returned a published comparison in a different condition that its abstract describes as randomized. It involved 30 women aged 38 to 46 with diminished ovarian reserve, in three groups of 10 treated with autologous exosomes, PRP or saline, and we read only its abstract.[24] Registered hair loss trials that compare an exosome or secretome product with PRP turned up in a ClinicalTrials.gov search on October 1, 2026, including NCT06239207, completed in July 2024, and NCT07429253, which is recruiting. Neither of those two records posts results or lists a publication, and the search returned no registered trial of that kind for facial skin.[25][26]

A 2026 meta-analysis reported a pooled percentage reduction in facial wrinkles, but the figure is a change from before treatment within treated groups and is not a comparison with a control group.[18]

These split-face skin trials tested exosome products applied to the skin after microneedling or radiofrequency microneedling, and did not test injection into the skin.

Exosome injections in the skin

Searches of PubMed, Europe PMC and ClinicalTrials.gov on October 1, 2026 found no published trial that compared exosome products injected into the skin with a placebo or with untreated skin for skin rejuvenation. As of October 1, 2026, ClinicalTrials.gov also lists a registered trial, NCT07227883, that compares a secretome product injected into the skin with saline injections for facial rejuvenation. It has 24 planned participants, is recruiting and has posted no results.[27] A pilot study that calls itself randomized and controlled injected exosomes prepared from each participant's own platelet-rich plasma into one side of the face in 11 women, 9 of whom finished, and reported changes from before treatment on the treated side without comparing the two sides.[28] Two of that pilot study's three authors work for the company that makes the device used to prepare the injections.

Four of the published reports that a Europe PMC search on October 1, 2026 returned describe a total of seven people who developed skin reactions after exosome products were injected into the skin, including persistent nodules, scarring and death of skin tissue.[29][30][31][32] The same search returned another report, titled 'Persistent Cutaneous Reaction After Facial Exosome Injections and Microneedling', which has no abstract in Europe PMC and which we could not read.[33]

In a case series of four adult women, lasting redness, nodules and scarring followed injection of exosome-containing products into the skin in a nonclinical setting, and all four were left with some scarring.[29] Two of the case reports each describe a man who developed painful skin lesions with death of skin tissue within days of exosome injections into facial skin, given in one case for acne scars and in the other for enlarged pores.[31][32]

Case reports cannot show how often skin reactions follow exosome injections, and our searches of PubMed, Europe PMC and ClinicalTrials.gov on October 1, 2026 found no estimate of that rate in the titles or abstracts we read. The skin reaction reports that we read involve exosome products injected into the skin and say nothing about products applied to the skin surface.

Exosome injections for knee arthritis

Research in people does not show that exosome injections help knee arthritis: in searches of PubMed, Europe PMC and ClinicalTrials.gov on October 1, 2026, a placebo-controlled trial we found (31 patients enrolled, 29 analysed) saw no difference from saline, and the other human studies we read had no placebo group.

A placebo-controlled trial of extracellular vesicle injections for knee osteoarthritis enrolled 31 patients and analysed 29. Each patient had a placenta-derived preparation injected into one knee and saline into the other, and the two knees did not differ in pain, function or MRI findings after 6 months.[34] The knee trial tested a single injection of one placenta-derived preparation, so the trial does not tell us about other products or repeated injections. The placebo-controlled knee trial reported no external funding.[34]

A retrospective study of 29 patients given six injections of umbilical cord vesicles reported improvement in pain and function scores compared with before treatment, and had no placebo or untreated group.[35] Another study gave rising doses of an umbilical cord exosome product for knee osteoarthritis and judged the results against scores before treatment.[36] Animal studies of extracellular vesicle injections for arthritis have reported less cartilage damage than in untreated animals; animal results do not show an effect in people.[37]

FDA's consumer alert dated July 22, 2020 (FDA page content current as of April 9, 2024) says none of the regenerative medicine products it names, including exosome products, 'have been approved for the treatment of any orthopedic condition'.

Exosomes and aging

In PubMed, Europe PMC and ClinicalTrials.gov searches on October 1, 2026, we found no controlled study in people showing that exosome treatments slow aging or extend life.

Our searches also found a published pilot study in 16 healthy adults aged 46 to 72, of whom 14 completed it. Over 17 weeks they had two intravenous infusions of a conditioned medium that contains extracellular vesicles, along with lifestyle changes and supplements, and the paper reports lower biological age scores at the end. The pilot had no comparison group and gave several treatments together, so it cannot show that the infusions caused the change.[38][39] We grade it as Experimental evidence.

The paper says financial support was not received for the work. Its authors work for two organizations, and the ClinicalTrials.gov record lists a company as the sponsor and those two organizations as collaborators.[38][39]

As of October 1, 2026, ClinicalTrials.gov also lists registered trials of extracellular vesicle products for aging related outcomes, for example NCT07322224, which is completed, and NCT06495437, which is not yet recruiting. Neither record posts results.[39][40]

Our searches did find a phase 1 trial that gave an engineered vesicle product by infusion to healthy adults: a placebo-controlled safety trial of a single dose in 18 volunteers that did not measure aging or wellness. Most of its authors worked for or held shares in the company developing the product.[41]

A 2019 mouse study reported that aged mice given vesicles from young mice lived longer, and searches of PubMed, Europe PMC and ClinicalTrials.gov on October 1, 2026 found no test in people of giving young donors' vesicles to extend life.[42]

There is no FDA-approved exosome product for any use, including longevity or healthy aging, according to FDA's consumer alert dated July 22, 2020 (FDA page content current as of April 9, 2024; status as of September 30, 2026).

What did the ExoFlo COVID trial find?

In a randomized, placebo-controlled phase 2 trial of 102 patients with COVID-19 and moderate to severe acute respiratory distress syndrome, the higher dose of ExoFlo, an extracellular vesicle product given into a vein, did not significantly lower deaths at 60 days compared with placebo in the main analysis (p = 0.1343).[43] A statistically significant lower death rate with the higher dose of ExoFlo appeared only in a post hoc subgroup analysis of 50 patients, which is an analysis chosen after the trial's results were known. The ExoFlo trial was funded by the company that sells ExoFlo, and its authors included people who work or have worked for that company.[43][44]

For stem cell vesicle products as a group in COVID-19 or acute respiratory distress syndrome, the evidence on deaths is Emerging (mixed). A 2026 review pooled three controlled trials in patients with those illnesses and reported lower odds of death.[4] We read only the review's abstract, which does not name the three trials or their products and does not say who funded them, so we cannot tell whether the ExoFlo trial is one of the three. The abstract says more controlled studies are needed to confirm the result. The label is mixed because the review's pooled result and the ExoFlo trial's result differ.

A systematic review published in 2026 pooled patient data from three controlled trials of stem cell vesicles in COVID-19 or acute respiratory distress syndrome and reported lower odds of death with treatment.[4] The ExoFlo trial of 102 patients did not meet its own main outcome, and the pooled result is early evidence. The abstract of that review does not report who funded the three pooled trials, and the abstract is the only part of the review we read.

The ExoFlo trial reported no adverse events related to treatment; a trial of 102 patients is too small to show uncommon harms. Other published reports of ExoFlo in COVID-19 that we read had no control group.[45][46]

The vesicle products in the COVID-19 trials were trial products given to hospital patients with severe lung failure, and the trials did not test exosome products sold by clinics or med spas.

FDA's consumer alert dated July 22, 2020 (FDA page content current as of April 9, 2024) says none of the regenerative medicine products it names, including exosome products, 'have been approved for the treatment or prevention of COVID-19'.

What has FDA said about exosome products?

There is no FDA-approved exosome product for any use, according to FDA's Consumer Alert on Regenerative Medicine Products Including Stem Cells and Exosomes, dated July 22, 2020 (FDA page content current as of April 9, 2024).

In its Public Safety Notification on Exosome Products (December 6, 2019), FDA said: 'There are currently no FDA-approved exosome products.' FDA also said: 'As a general matter, exosomes used to treat diseases and conditions in humans are regulated as drugs and biological products under the Public Health Service Act and the Federal Food Drug and Cosmetic Act and are subject to premarket review and approval requirements.'

FDA's notification

In its Public Safety Notification on Exosome Products (December 6, 2019), FDA advised patients considering exosome treatment in the United States: 'Ask if the FDA has reviewed the treatment.' FDA added that patients can ask the clinical investigator for the FDA-issued Investigational New Drug Application (IND) number before treatment.

Regulatory status checked September 30, 2026. Sources: www.fda.gov/…/public-safety-notification-exosome-products; www.fda.gov/…/consumer-alert-regenerative-medicine-products-including-stem-cells-and-exosomes; www.fda.gov/…/approved-cellular-and-gene-therapy-products

Why did FDA issue a safety notification about exosome products in 2019?

In its Public Safety Notification on Exosome Products (December 6, 2019), FDA told the public of 'multiple recent reports of serious adverse events experienced by patients in Nebraska who were treated with unapproved products marketed as containing exosomes.' The notification does not name the type of adverse event, the number of patients, or any product or clinic.

FDA's notification

A page from the Centers for Disease Control and Prevention (CDC), last reviewed on December 19, 2019 and now archived, said that patients in Nebraska who were treated with products marketed as containing exosomes had serious adverse events, including bacterial infections.[47]

A Nebraska Department of Health and Human Services advisory dated December 6, 2019 described people treated in Nebraska who became ill after receiving a product made from C-section placentas, some of whom developed bacteria in the bloodstream.[48]

Neither the CDC page nor the Nebraska advisory gives the number of patients treated in Nebraska who were affected, and neither names the product or the clinic involved in the Nebraska cases.

The Nebraska advisory, which covered products derived from stem cells, placenta and umbilical cord blood, told clinicians to consider a procedure-related infection in patients who had received these types of therapies.[48]

What are the risks of exosome treatments?

Reports of harm after exosome products include bacterial infections in Nebraska patients in 2019 and skin reactions after injections into the skin, and no source we read says how often either happens. In the small clinical trials of exosome and extracellular vesicle products that we read, the reported side effects were mostly mild and short-lived. Those trials were too small and too short to detect rare or delayed harms.

A systematic review of 25 clinical trials of extracellular vesicles found that adverse event reporting was often incomplete and called its safety conclusions preliminary.[4] In PubMed and Europe PMC searches on October 1, 2026, we found no study designed to assess the long-term safety of marketed exosome products. ClinicalTrials.gov also holds registered trials of exosome or extracellular vesicle products that list a long-term safety or adverse event outcome with follow-up of 6 months or longer, as a search on October 1, 2026 showed. Examples are NCT04664738, a skin graft donor site wound with a 6 month outcome, and NCT05490173, extremely low birth weight infants with a 3 year outcome. None of the records that search returned with such an outcome has posted results.[49][50]

If you have severe symptoms, call 911 or seek emergency care. Report side effects to FDA MedWatch.

Contraindication considerations

In PubMed and Europe PMC searches on October 1, 2026, we found no published list of conditions or medicines that rule out treatment with exosome products.

Anyone thinking about an exosome product, or who has a fever or chills after receiving one, should talk with a licensed clinician.