Summary
Metformin is tracked by OSMF as an investigational option for ME/CFS; no regulator has approved it for this indication, and most post-viral conditions have no approved disease-modifying therapy at all. ClinicalTrials.gov lists 1 registered trial linking Metformin to ME/CFS: 1 has completed. The most advanced is Phase 3 (NCT06128967, sponsored by Cardresearch). It plans or enrolled 399 participants. Registered activity dates to 2023. The literature layer holds 3 publications for this pair: 3 curated references. The dated items are from 2025. Items here are search-derived or curated references rather than classified trial reports; treat them as leads to read, not as graded evidence.
Myalgic Encephalomyelitis / Chronic Fatigue Syndrome is tracked on the OSMF post-viral programme alongside ME/CFS, Long COVID, POTS and MCAS. Across the programme, 191 candidate agents are logged for ME/CFS, most of them preliminary; this page isolates the record for one of them.
Evidence table
| Evidence tier | B · Moderate |
|---|---|
| Evidence score | 19.0 (trials 4.5, literature 4.5, tier 10, approved bonus 0.0) |
| Registered trials | 1 total: 0 recruiting, 0 active / not yet recruiting, 1 completed, 0 other |
| Linked publications | 3 (3 curated references) |
| Agent type | Drug (Drug (Pharmaceutical)) |
| Development stage (any indication) | Investigational |
| Mechanism / class | Anti-inflammatory; Metabolic / Mitochondrial |
| Data sources | OSMF therapeutic agent database, ClinicalTrials.gov, PubMed |
| Also known as | Metformin |
How the evidence score is calculated
- Each registered trial scores by status (recruiting / active / enrolling 3, completed 2.5, not yet recruiting 2, unknown 1, terminated / withdrawn / suspended 0.5) plus a phase bonus (phase 3-4 +2, phase 2 +1, phase 1 +0.5). The trial component is capped at 30.
- Each literature item scores by design (Cochrane review 5, meta-analysis 4, systematic review 3, RCT 3, clinical trial publication 2, curated reference 1.5, other PubMed record 1). The literature component is capped at 30.
- The existing evidence tier adds 15 (A / Strong), 10 (B / Moderate), 5 (C / Preliminary) or 0 (D / Anecdotal).
- Agents approved for any indication (max clinical phase 4) add 5, because an approved agent has an established safety profile that lowers the barrier to repurposing trials.
- The score ranks what has been studied, not what works. It does not read effect sizes or directions of effect.
Registered clinical trials
| NCT ID | Title | Status | Phase | Enrolment |
|---|---|---|---|---|
| NCT06128967 | A Multicenter, Adaptive, Randomized, doublE-blinded, Placebo-controlled Study in Participants With Long COVID-19: The REVIVE Trial Cardresearch · 2023 | completed | Phase 3 | 399 |
Published literature
- Curated reference (OSMF) Mitochondria-targeted therapy with metformin and MitoQ reduces oxidative stress, improves mitochondrial function, and restores metabolic hom2025
- Curated reference PubMed record PMID 40544605
- Curated reference (PACVS Evidence Map) Clinician-diagnosed long COVID halved at 6 months (RR 0.495; 95% CI 0.155–0.995); prevention not treatment; concordance across two independent trialsPACVS Evidence Map
Mechanism and notes
Recorded mechanism or class: Anti-inflammatory; Metabolic / Mitochondrial.
Clinical notes: Prevention signal strong; treatment data mixed/preliminary. 500-2000mg. GI effects, B12. Reasonable metabolic adjunct in overweight PASC patients.
Safety: GI side effects (diarrhea, nausea) common initially. Risk of B12 deficiency long-term; lactic acidosis rare (avoid in severe renal/hepatic disease, contrast).
Dosing in studies: 500–2000 mg/day (extended release often better tolerated); prevention trials used during acute infection ~14 days; treatment studies 8–12+ weeks.
Frequently asked questions
Is Metformin approved for ME/CFS?
Metformin is tracked by OSMF as an investigational option for ME/CFS; no regulator has approved it for this indication, and most post-viral conditions have no approved disease-modifying therapy at all. Approval status for the specific indication should always be confirmed with the relevant regulator and prescribing information.
Is Metformin in clinical trials for ME/CFS?
ClinicalTrials.gov lists 1 registered trial linking Metformin to ME/CFS: 1 has completed. The most advanced is Phase 3 (NCT06128967, sponsored by Cardresearch). It plans or enrolled 399 participants. Registered activity dates to 2023.
What does the evidence show for Metformin in ME/CFS?
Metformin has 1 completed trial and 3 linked publications for ME/CFS. Completed trials may or may not have posted results; follow the NCT links to check. OSMF's existing evidence tier for this pair is B (Moderate), taken from the OSMF therapeutic agent database, which grades agents by the volume and design of condition-specific evidence rather than by effect size.
Cite this page
Data: ClinicalTrials.gov, PubMed, Open Targets, ChEMBL, DGIdb and the OSMF therapeutic agent database. Last updated 2026-10-07. Page built 2026-10-07.