Editorially reviewed · Last updated November 3, 2026 · How we review
Part of Peptides Topic Hub.
Key findings
- MOTS-c is not FDA-approved, and FDA's May 2026 review found no published studies giving it to people as a treatment.
- Since October 30, 2026, HHS enforcement discretion covers single-ingredient MOTS-c acetate injections compounded by 503A pharmacies for individual prescriptions, under conditions.
- Its metabolic effects come from mouse and lab studies; FDA says their clinical relevance is unknown and found no dose-response data.
- The July 23, 2026 advisory committee voted 7–5 to recommend it, against FDA staff advice.
- A 120-person placebo-controlled Phase 2 trial in prediabetes began recruiting in February 2026.
- MOTS-c is prohibited in sport under the WADA list.
MOTS-c: Legal Status, Human Evidence and the HHS Compounding Policy
MOTS-c is not an FDA-approved drug, and no published study has tested it as a treatment in people. Since October 30, 2026, HHS has said it does not intend to take enforcement action against state-licensed 503A pharmacies compounding MOTS-c acetate injections for an individual patient's prescription, under strict conditions (Federal Register notice 2026-22192).
Is MOTS-c legal?
| Question | Answer |
|---|---|
| FDA-approved drug? | No. MOTS-c is not a component of any FDA-approved drug |
| Covered by the October 30, 2026 HHS policy? | Yes, MOTS-c acetate by subcutaneous or intramuscular injection |
| Who can compound it under the policy? | A state-licensed 503A pharmacy, federal facility or licensed physician, for a patient-specific prescription |
| Blends with other peptides? | Not covered. Each product may contain only a single active ingredient |
| “Research use only” vials? | Not covered by the policy |
| On the final 503A Bulks List? | No. That requires FDA rulemaking, and no proposed rule had been published as of November 3, 2026 |
| Allowed in sport? | No. WADA's Prohibited List names MOTS-c as a hormone and metabolic modulator, and FDA's review notes it is listed as prohibited |
What does the human evidence show?
- No human treatment studies. The nomination "cited 12 literature references in support of the nomination; these did not include clinical studies", and FDA's own search found none.
- Animal and lab data only. Studies of MOTS-c's effects "were limited to in-vitro and in-vivo rodent models", so "the clinical relevance of the findings of these nonclinical studies is currently unknown."
- No dose-response data. FDA says dose-response assessments are missing and the molecular target through which MOTS-c acts remains unknown.
- Unknown safety. FDA concluded that "potential safety risks associated with the use of MOTS-c in humans are unknown", and said there is too little information to assess the risk of an immune reaction to the injected peptide.
The first placebo-controlled trial of native MOTS-c is under way
Does MOTS-c help with weight loss?
What is the MOTS-c dose?
No human dose has been established. No published trial has tested a dose of native MOTS-c in people, and FDA found no dose-response data. Doses shared online are not validated by clinical evidence. A prescriber choosing a regimen is working without trial data, which is worth asking about directly.
Frequently Asked Questions
Is MOTS-c FDA approved?
No. MOTS-c is not a component of any FDA-approved drug. The October 30, 2026 HHS policy concerns enforcement discretion for compounding, not approval.
Is MOTS-c legal in the US?
Since October 30, 2026, HHS has said it does not intend to take enforcement action against state-licensed 503A pharmacies compounding single-ingredient MOTS-c acetate for subcutaneous or intramuscular injection on a patient-specific prescription, if the policy's conditions are met. "Research use only" vials and blends are outside the policy.
Has MOTS-c been tested in humans?
Not as a treatment in any published study. FDA's May 2026 review found no clinical studies giving MOTS-c to people. A 120-person placebo-controlled Phase 2 trial in adults with prediabetes and overweight or obesity began recruiting in February 2026; primary completion is estimated for February 2027.
Does MOTS-c cause weight loss?
There is no human evidence that it does. The metabolic effects come from mouse studies, and FDA said their clinical relevance is unknown.
Is MOTS-c banned in sport?
Yes. The World Anti-Doping Agency's Prohibited List names MOTS-c as a hormone and metabolic modulator, and FDA's review notes it is listed as prohibited.
Sources
- HHS. Federal Register notice 2026-22192, published October 30, 2026, and the HHS policy document.
- FDA. Evaluation of MOTS-c-related bulk drug substances, briefing document for the July 23–24, 2026 Pharmacy Compounding Advisory Committee, dated May 11, 2026.
- FDA. July 23–24, 2026 Pharmacy Compounding Advisory Committee meeting.
- AJMC. FDA panel backs 6 peptides for compounding, July 2026.
- ClinicalTrials.gov. NCT07505745: MOTS-c for improving insulin sensitivity in adults with prediabetes and overweight/obesity.
- ClinicalTrials.gov. NCT03998514: CB4211 Phase 1.
- Lee, C., et al. (2015). The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance. Cell Metabolism, 21, 443–454. DOI.
- Reynolds, J.C., et al. (2021). MOTS-c is an exercise-induced mitochondrial-encoded regulator of age-dependent physical decline and muscle homeostasis. Nature Communications. Nature.
- Related on this site: Are Peptides Legal in 2026? · BPC-157 · TB-500 · Peptides vs GLP-1
- What this is
- Educational information, not medical advice. It reports published research — it doesn’t recommend that you use, obtain, or supply anything.
- Regulatory status
- Retatrutide and similar peptides are investigational — not approved by the FDA or any regulator. Semaglutide and tirzepatide are prescription-only medicines, available only through a licensed prescriber.
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Do not make decisions about your health without consulting a qualified healthcare provider. For trial enrolment, see ClinicalTrials.gov. More on how we review.
Sources
- HHS peptide compounding policy (Federal Register)
Federal Register
- FDA MOTS-c briefing document
FDA.gov
- MOTS-c Phase 2 trial
ClinicalTrials.gov
NEJM
The Lancet
JAMA
FDA
ClinicalTrials.govRelated reading
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