The short answer. Mesenchymal stem cells (MSCs) were studied in patients hospitalised with severe COVID, with some signs of better lung recovery. For long COVID itself, controlled evidence is very limited: one small randomised trial of a cord blood cell product (not MSCs) reported less fatigue. For chronic fatigue syndrome (ME/CFS), I am not aware of any controlled trial of stem cells or exosomes. The evidence is still early, and the first step is always to look for treatable causes of fatigue.
Stem cell and exosome treatment for long COVID and chronic fatigue is offered as an adjunct: alongside established medical care, a healthy lifestyle and, where appropriate, your main treatment protocol, never instead of them. The clinical evidence for long COVID and chronic fatigue is still developing, and I will tell you exactly what it does and does not show.
What long COVID and ME/CFS are
The World Health Organization defines long COVID (post-COVID-19 condition) as symptoms that usually start within three months of a COVID infection, last at least two months and cannot be explained by another diagnosis. Fatigue, breathlessness and problems with memory and concentration are the most common.1
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) overlaps with long COVID and can follow other infections. There is no approved treatment; care focuses on managing symptoms, and fewer than 5% of patients return to their previous level of activity.2 It is easy to see why people with either condition look at newer options.
Start here: rule out treatable causes
Fatigue after an infection is not always long COVID. Before considering any regenerative treatment, I check for causes that have proven treatments: thyroid problems, anaemia and low iron, vitamin B12 and vitamin D deficiency, blood sugar problems, sleep apnoea, heart rhythm and blood pressure problems such as POTS, medication side effects, and depression or anxiety. Finding one of these is better news than any experimental option.
Exhausted since COVID?
Start with a proper assessment. Bring any recent blood tests, and I will tell you what to check first.
What did stem cells do in severe COVID?
Most of the human evidence comes from patients who were in hospital with severe COVID, not from long COVID. In one randomised, placebo-controlled trial of 100 patients, those given umbilical cord MSCs had smaller lung lesions ten days after treatment, and at one year 18% had a normal lung CT, against none in the placebo group.3
Three years later, the picture was more modest. The difference in lung CT was no longer statistically significant, and long COVID symptoms did not differ between the groups: fatigue or muscle weakness was still reported by 57% of patients overall. The treated group did score better on one general health measure, and no excess of complications or tumours was seen.4
So MSCs may help lung recovery after severe COVID, but in this trial they did not prevent long COVID symptoms over three years.
What about treating long COVID itself?
The most relevant result so far comes from a small trial of 30 people with post-COVID fatigue, randomised to three infusions of a donor cord blood cell product or placebo. The treated group reported less fatigue from six weeks, and the improvement lasted to the end of the 20-week follow-up. Quality of life improved in some areas, but there was no change in cognition or frailty.5
Two cautions matter. The product contained blood-forming cells from cord blood, not MSCs, so the result cannot simply be applied to MSC or exosome treatment. And the trial was small and single-blind: participants did not know which infusion they received, but the investigators did. Trials of MSCs in long COVID are under way, but as far as I could find, none has yet published controlled results in a peer-reviewed journal.
And chronic fatigue syndrome (ME/CFS)?
I am not aware of any controlled trial of stem cells or exosomes in ME/CFS. Any stem cell or exosome treatment offered for ME/CFS is therefore untested, and you should know that before you decide.
Stem cells or exosomes?
Exosomes are a cell-free option for patients who prefer not to receive living cells; MSCs are a cell-based option. In my clinical experience, some patients report earlier changes following exosome treatment, whereas responses following MSC treatment may develop more gradually. No comparative trial in long COVID has shown this. It is clinical observation, not trial evidence.
How would we know whether it helped?
Fatigue is easy to feel and hard to measure, so we record a baseline and repeat the same measures at about three and six months:
- A standard fatigue questionnaire, such as the one used in the long COVID trial above.
- Quality of life, using a validated questionnaire.
- Activity, such as daily steps, and whether exertion makes symptoms worse afterwards.
- Memory and concentration, recorded the same way each time.
A note on pacing
Many people with long COVID or ME/CFS feel worse a day or two after physical or mental exertion. If that happens to you, increasing activity too quickly can set you back. Pacing your activity matters whatever else you try, and it is something we plan together.
Is it safe?
Across 55 randomised trials and 2,696 patients in other conditions, the only side effect clearly linked to MSC drips was a short-lived fever. The pooled analysis did not detect an increased rate of infection, thrombotic events or malignancy during the available follow-up.6 That does not exclude rare or long-term risks.
At our clinic, cells and exosomes are prepared by two established, regulated laboratories: one Italian, operating since 2009 and in Dubai since 2013, and one British, in Dubai since 2017. Every patient is screened and assessed before treatment.
Who should not have it
- Anyone with active cancer or a recent cancer history.
- Pregnancy, or actively trying to conceive.
- Active infection.
- Fatigue that has not yet been properly investigated.
Frequently asked questions
Can stem cells cure long COVID?
No. There is no proven cure for long COVID, and the evidence for stem cells and exosomes is still early.
Will stem cells help my fatigue?
One small trial of a cord blood cell product reported less fatigue,5 but MSCs and exosomes have not yet been shown to help long COVID fatigue in controlled trials.
Can stem cells repair lung damage after COVID?
In patients treated during severe COVID, MSCs were linked to better lung recovery at one year,3 but the difference was no longer significant at three years.4
Is cord blood therapy the same as MSC therapy?
No. Cord blood products contain mainly blood-forming cells; MSCs are a different cell type. Results for one cannot be assumed for the other.
Can stem cells help ME/CFS?
I am not aware of any controlled trial of stem cells or exosomes in ME/CFS.
Book an assessment.
An honest assessment of your fatigue, starting with the causes that have proven treatments.
This article is patient education and does not replace the advice of your own doctor.
References
- Soriano JB, Murthy S, Marshall JC, Relan P, Diaz JV; WHO Clinical Case Definition Working Group on Post-COVID-19 Condition. A clinical case definition of post-COVID-19 condition by a Delphi consensus. Lancet Infect Dis. 2022;22(4):e102–e107. doi:10.1016/S1473-3099(21)00703-9
- Seton KA, Espejo-Oltra JA, Giménez-Orenga K, Haagmans R, Ramadan DJ, Mehlsen J. Advancing research and treatment: an overview of clinical trials in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and future perspectives. J Clin Med. 2024;13(2):325. doi:10.3390/jcm13020325
- Shi L, Yuan X, Yao W, et al. Human mesenchymal stem cells treatment for severe COVID-19: 1-year follow-up results of a randomized, double-blind, placebo-controlled trial. EBioMedicine. 2022. sciencedirect.com
- Yuan MQ, Song L, Wang ZR, et al. Long-term outcomes of mesenchymal stem cell therapy in severe COVID-19 patients: 3-year follow-up of a randomized, double-blind, placebo-controlled trial. Stem Cell Res Ther. 2025;16:94. doi:10.1186/s13287-025-04148-1
- Huang YW, Chen YC, Lau EYL, et al. REGENECYTE cord blood cell therapy in post-COVID syndrome: a phase IIa randomized, placebo-controlled trial. eClinicalMedicine. 2026. thelancet.com
- Thompson M, et al. Cell therapy with intravascular administration of mesenchymal stromal cells continues to appear safe: an updated systematic review and meta-analysis. EClinicalMedicine. 2020;19:100249. doi:10.1016/j.eclinm.2019.100249
This article is part of my guide to regenerative medicine in Dubai. If you are considering treatment, read how I assess stem cell therapy in Dubai.
