Long COVID and Mesenchymal stem/stromal cells (MSC): what the trial registry contains
The ClinicalTrials.gov registry holds 8 records for MSC in Long COVID: 1 recruiting now, 0 labelled Phase 3 or 4, across 2 countries. Snapshot 2026-08-29.
Why this is studied in Long COVID
Long COVID is a heterogeneous post-viral syndrome spanning autonomic dysfunction, exercise intolerance and cognitive symptoms, with no accepted biomarker. Cell rationales target persistent inflammation and endothelial dysfunction. Heterogeneity is the central research problem: several distinct conditions are probably being studied under one label.
What MSC means in this table
Mesenchymal stromal cells are the workhorse of commercial cell therapy: easy to source from fat, cord or marrow, easy to expand, and rarely characterised in the same way twice. Their proposed action is paracrine — signalling molecules that damp inflammation — rather than replacement of lost tissue. That matters when reading counts like these, because two studies filed under the same label can test materially different products at different doses by different routes.
The numbers
Every figure below comes from one reproducible query (post-acute COVID-19 syndrome x mesenchymal stem cell) run against ClinicalTrials.gov API v2 on 2026-08-29.
| Metric | Value |
|---|---|
| Registered studies (all statuses) | 8 |
| Interventional studies in the sample | 7 |
| Recruiting right now | 1 |
| Completed | 1 |
| Terminated, withdrawn or suspended | 2 |
| Phase 3 or Phase 4 records | 0 |
| Countries with at least one site | 2 |
| Median planned enrolment | 76 participants |
| Largest single planned enrolment | 80 participants |
| First / most recent start year | 2022 — 2024 |
How mature is this evidence?
The evidence base is small and unfinished: 8 registered records with no later-phase work and 1 enrolling.
Registrations do not all survive contact with recruitment — 1 completed here, 2 stopped early, giving a 25% attrition rate.
| Phase label | Records | Share |
|---|---|---|
| Phase 2 | 4 | 40% |
| Phase 1 | 4 | 40% |
| Not applicable | 1 | 10% |
| Early Phase 1 | 1 | 10% |
Median planned enrolment is 76 participants (largest single study: 80). Trials of this size can describe safety and generate hypotheses; detecting a modest clinical benefit reliably usually needs substantially larger numbers with a control group.
Where the studies are
Country coverage runs to 2, but the distribution has a long tail behind United States at about 50% of mentions.
| Country | Studies with a site there |
|---|---|
| United States | 3 |
| China | 3 |
Legal pathway differs by country — see where cell therapy is legal, by country.
Who runs them
The sponsor mix is academic (5 academic or hospital, 2 commercial among the most frequent lead sponsors).
- Hope Biosciences Research Foundation — 2 records
- Shanghai East Hospital — 1 record
- Huazhong University of Science and Technology — 1 record
- Charles Cox — 1 record
- Direct Biologics, LLC — 1 record
- Changhai Hospital — 1 record
Representative registered studies
Recruiting studies first, then the most advanced phases. Each identifier links to the registry record, where eligibility criteria, outcome measures and contacts are published.
| Study | Phase | Status | Planned n | Lead sponsor | Start |
|---|---|---|---|---|---|
| NCT06492798 — Effectiveness and Safety of Mesenchymal Stem Cell Therapy in Long COVID Patients | Phase 1, Phase 2 | Recruiting | 76 | Changhai Hospital | 2023-09-01 |
| NCT05116761 — ExoFlo™ Infusion for Post-Acute COVID-19 and Chronic Post-COVID-19 Syndrome | Phase 1, Phase 2 | Withdrawn | n/a | Direct Biologics, LLC | 2024-11 |
| NCT05719012 — Efficacy and Safety of Umbilical Cord Mesenchymal Stem Cells in the Treatment of Long COVID-19 | Phase 2 | Withdrawn | n/a | Shanghai East Hospital | 2023-04-01 |
| NCT05126563 — Randomized Double-Blind Phase 2 Study of Allogeneic HB-adMSCs for the Treatment of Chronic Post-COVID-19 Syndrome | Phase 2 | Completed | 79 | Hope Biosciences Research Foundation | 2022-02-02 |
| NCT06156241 — Stem Cell Study for Long COVID-19 Neurological Symptoms | Phase 1 | Unknown | 12 | Charles Cox | 2024-01 |
| NCT05669261 — Treatment of Long COVID Symptoms Utilizing Autologous Stem Cells Following COVID-19 Infection | Phase 1 | Unknown | 20 | American CryoStem Corporation | 2023-08-01 |
| NCT05808400 — Safety and Efficacy of Umbilical Cord Mesenchymal Stem Cell Exosomes in Treating Chronic Cough After COVID-19 | Early Phase 1 | Unknown | 80 | Huazhong University of Science and Technology | 2023-02-15 |
| NCT04798066 — Intermediate Size Expanded Access Protocol for the Treatment of Post-COVID-19 Syndrome | n/a | No Longer Available | n/a | Hope Biosciences Research Foundation |
What this page does and does not tell you
A registry is a plan repository. Counting entries tells you what people intended to study, which is a weaker thing than what they found.
If a clinic offers you this today, the useful question is not "is there research?" but "which of these registered studies is mine part of, and if none, what evidence applies to the exact product I am being sold?" The Provider Question Builder turns that into a scored checklist.
Frequently asked
How many MSC studies for Long COVID are recruiting right now?
1 of 8 registered records were listed as recruiting in the 2026-08-29 snapshot. Recruitment status changes frequently; the registry record is authoritative.
Is MSC an approved treatment for Long COVID?
Registration on ClinicalTrials.gov is not approval. Approval is granted by a regulator for a specific product and indication after review of submitted evidence. 8 registered studies tell you research exists, not that a product cleared review.
How advanced is the research on MSC for Long COVID?
0 of 8 records carry a Phase 3 or Phase 4 label and 1 are marked completed. Registrations run from 2022 to 2024.
Registry and literature counts retrieved 2026-08-29 (ClinicalTrials.gov API v2; PubMed E-utilities). Registration or publication volume measures research activity, not effectiveness or approval. Educational information — not medical advice; verify product, indication, legal pathway and evidence with an independent qualified physician. Page generated 2026-08-29. See our editorial standards.
Download the query data
Query totals are full API matches; status, phase and country counts describe the first up to 400 returned records per query. Query classes overlap and must not be summed as unique trials. Counts are not treatment outcomes. Snapshot: 2026-08-29. Methods and field definitions.