Metabolic · 7 min read · Published September 8, 2026

MOTS-c: The Mouse Data, the One Human Trial, and the 7 to 5 FDA Vote

What MOTS-c is, why it is called an exercise mimetic, why no completed human trial exists as of 2026, what the Phase 2a in prediabetes will measure, and what the July 2026 advisory vote does and does not change.

What does MOTS-c do?

MOTS-c is a 16 amino acid peptide encoded in mitochondrial DNA. In mice it activates AMPK, improves insulin sensitivity and mimics some effects of exercise. As of 2026 no completed human trial of MOTS-c exists; one Phase 2a study in prediabetes (NCT07505745) is recruiting. An FDA advisory committee voted 7 to 5 to recommend it for compounding.

MOTS-c stands for mitochondrial open reading frame of the 12S rRNA type-c. It was described in 2015 by Changhan Lee and Pinchas Cohen's group as a hormone made from the mitochondrial genome that signals to the rest of the cell and, in mice, to the whole body. The finding that a mitochondrial gene encodes a metabolic regulator was genuinely new, and it is the reason MOTS-c gets more scientific respect than most peptides sold alongside it. Our profile is at MOTS-c.

What the mouse studies showed

• In the original Cell Metabolism paper, MOTS-c injections prevented diet-induced obesity and insulin resistance in mice and shifted muscle metabolism through AMPK and the folate cycle.
• In 2021, Reynolds and colleagues showed MOTS-c treatment doubled running capacity in old mice and that levels rise in human muscle after exercise, which is where the exercise-mimetic label comes from (Nature Communications, 2021).
• Later work found circulating MOTS-c falls with age in people and is lower in some metabolic diseases, and a 2026 paper reported that MOTS-c also acts as an interferon-linked host-defense peptide (PubMed, 2026), a reminder that its biology is broader than fat loss.

Is there a human trial of MOTS-c?

One is running. NCT07505745 is a Phase 2a study of MOTS-c in adults with prediabetes, with insulin sensitivity (the Matsuda index) as the primary endpoint over 12 to 16 weeks. It began recruiting in 2026 and is the first controlled human trial of unmodified MOTS-c. No results exist yet.

The only earlier human data came from CB4211, a modified MOTS-c analog developed by CohBar. It completed a Phase 1a/1b in 2021 with a reduction in liver enzymes and a modest weight signal, after which the company wound down the program. That result says something about the pathway and nothing about the exact peptide sold today. You can read the registration at ClinicalTrials.gov NCT07505745.

What did the FDA vote mean?

On July 24, 2026 the Pharmacy Compounding Advisory Committee voted 7 to 5 to recommend MOTS-c for the 503A bulk-drug list, the narrowest margin of the meeting. FDA's briefing document had recommended against it, citing no adequate human data. The vote is advisory; MOTS-c cannot be legally compounded unless and until FDA completes rulemaking.

The FDA's MOTS-c briefing document is at FDA media 193347. For the full context of the meeting, including the votes on BPC-157, TB-500, KPV, Epitalon, Semax and DSIP, see our FDA peptide status tracker.

Does MOTS-c burn visceral fat?

In mice on a high-fat diet, MOTS-c reduced fat gain and improved metabolic markers. No human study has measured visceral fat, or any fat, after MOTS-c. Claims that it burns visceral fat in people extrapolate from rodent data and from the Phase 1 signal of a different, modified molecule.

What people report, and what is unknown

The most consistent report from people using gray-market MOTS-c is raised, itchy welts at the injection site that can last days. Whether that reflects the peptide, impurities or endotoxin cannot be known without tested product. There are no data on long-term use, on dosing frequency, or on interactions. The half-life in humans has not been measured; our half-life reference lists it as unknown for that reason.

Two questions that come up constantly have the same answer. 'Is MOTS-c the same as BPC-157?' No: different genes, different targets, both unapproved. 'How long should you take SS-31 before MOTS-c?' No trial has tested either sequence or the pair; see our SS-31 and elamipretide explainer.