On this page
- What a registered trial is and is not
- The shape of the field
- Where trials have actually reported
- Why so many trials produce so little
- How to check a trial claim yourself
- The commercial trial that is not a trial
- What the trial landscape suggests about timing
- Where this connects
- Frequently asked questions
- Requesting a medical evaluation
Thousands of trials have been registered in this field and a small fraction have reported anything useful. The MSC clinical trial landscape is worth understanding because the gap between registration and result is where most of the optimism in stem cell marketing actually lives — a registered trial is a plan, not a finding.
What a registered trial is and is not
Registration means a protocol was filed on a public registry before recruitment. It records what will be tested, in whom, measuring what, and to what timetable.
It is a discipline that exists to prevent outcome switching — changing what you measure after seeing the data — and to make it visible when a study finishes and reports nothing.
What registration does not do is establish that the treatment works, that the trial was completed, or that anyone ever published the result.
“Currently in clinical trials” is therefore one of the least informative sentences in medicine, and one of the most frequently deployed. It describes a stage of investigation, not a level of evidence.
The shape of the field
Registered MSC studies run into the thousands across dozens of conditions, and the number has grown steadily for two decades.
They cluster heavily in early phases. Phase I studies establish safety in small numbers; phase II look for signals of efficacy; phase III are the large comparative trials that change practice, and they are the rarest.
A field with many phase I studies and few phase III ones is a field that has generated a great deal of activity and relatively little settled knowledge.
A critical systematic review has examined the trial landscape for extracellular vesicles specifically — A critical systematic review of extracellular vesicle clinical trials — and the word “critical” in that title is doing real work.
Where trials have actually reported
Knee osteoarthritis is the clear leader, with enough completed randomised trials to support a 2025 systematic review and meta-analysis — Efficacy and safety of mesenchymal stem cells in knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials.
Autoimmune and rheumatic disease has enough for a synthesis — Efficacy and safety of mesenchymal stromal cell transplantation in the treatment of autoimmune and rheumatic immune diseases.
Beta cell preservation in diabetes has been examined through network meta-analysis — A systematic review and network meta-analysis of interventions to preserve insulin-secreting beta cell function.
And dose has been studied directly in a randomised phase 2b escalation design — Randomized phase 2b dose-escalation trial of stem cell therapy — which is the kind of study a maturing field produces.
Why so many trials produce so little
Small early-phase studies are not designed to answer efficacy questions, and a great many never progress beyond them.
Funding runs out. Academic groups complete a phase I, publish, and move on. Commercial sponsors abandon programmes that do not look promising, and those abandonments are rarely announced.
Recruitment is hard for conditions where patients can buy the treatment commercially without the inconvenience of randomisation — which is a genuine and underappreciated way the unregulated sector slows the research it cites.
And heterogeneity again: with every group using different cells, doses and routes, results accumulate without converging. Twenty small studies of twenty slightly different interventions do not add up to one large study of one.
How to check a trial claim yourself
If a clinic tells you a treatment is supported by trials, or that your treatment is part of one, this is checkable in a few minutes.
- Ask for the registry identifier — a real trial has one
- Look it up on a public registry and read the protocol
- Check the phase, the enrolment number and the primary outcome
- Check the status — recruiting, completed, terminated, or unknown
- Check whether results were posted, and whether a publication followed
A status of “unknown” for years, or a completed trial that never reported, tells you something the citation alone does not.
The commercial trial that is not a trial
Some clinics describe paid treatment as research participation. Occasionally that is legitimate; often it is a framing.
A real trial has ethics committee approval, a registered protocol, defined inclusion and exclusion criteria, systematic outcome collection and an obligation to report. It also does not usually charge full commercial rates, because charging patients to be experimented on inverts the relationship.
If treatment is described as a study, the protocol should be available to you, and your data should be going somewhere — see regulation in Thailand.
What the trial landscape suggests about timing
A field with this much registered activity and this few phase III results will look different in five to ten years. Some indications will firm up; others will quietly disappear from the literature.
That has a practical consequence for anyone weighing treatment now. For a progressive condition, waiting has a cost. For a stable one, it may not.
Neither answer is universal, and the honest framing is that you are making a decision inside a field that has not finished forming — see the limits of current evidence.
It is also worth knowing that waiting is not free in the other direction either. Prices fall as processes standardise, but a condition that progresses meanwhile is a condition that may move past the point where treatment was worth considering.
Where this connects
What the evidence levels mean explains how registered, reported and replicated differ.
The knee studies show what a comparatively mature indication looks like, and adverse events covers what trials do and do not capture.
The research library indexes the rest.
Frequently asked questions
Thousands of trials — does that mean it works?
No. Registration records a plan. Most are small early-phase studies, and many never report a result at all.
What does “in clinical trials” actually tell me?
That somebody is investigating it. It describes a stage of research, not a level of evidence, and it is among the least informative phrases in medicine.
Which indications have reported properly?
Knee osteoarthritis most clearly, with enough completed randomised trials for meta-analysis. Autoimmune disease and diabetes have syntheses of earlier work.
How do I check a trial a clinic cites?
Ask for the registry identifier, then look up the phase, enrolment, primary outcome, status and whether results were ever posted.
My treatment is described as part of a study.
Then ask for the protocol and the ethics approval. A real trial does not usually charge commercial rates, and your data should be going somewhere.
Why do so many trials go nowhere?
Funding ends, sponsors abandon unpromising programmes quietly, and recruitment is hard when patients can simply buy the treatment instead.
Requesting a medical evaluation
Nothing on this page establishes whether any treatment is appropriate for you. That needs your history, your imaging and your current medications read by a clinician. If you would like that review, send your records and we will tell you honestly whether there is anything worth discussing — including when the answer is no.
This page is general information, not medical advice, and does not create a doctor–patient relationship. Regenerative treatments discussed here are in most cases investigational. Discuss any treatment with a clinician who knows your history.