MOTS-c: The Mouse Data Is Good and the Human Trial Is Fabricated

What it is

MOTS-c is a chain of 16 amino acids, and the instructions for building it sit in the separate set of DNA carried by mitochondria, the compartments in a cell that turn food into usable energy. Those instructions hide inside a gene understood to do something else entirely, readable only if you start at a different point, like a recipe that also spells out a note to somebody else in the house if you begin at a different letter.

Eight peptides of this kind are known, MOTS-c and humanin among them. (PMID 37644144) MOTS-c was named in a 2015 Cell Metabolism paper from Lee, Zeng, Drew and colleagues at USC, who reported skeletal muscle as its main target. (PMID 25738459)

What the trials found

Start with the one that is not there.

ClinicalTrials.gov, the national registry for medical trials, lists NCT07505745: MOTS-c for improved insulin sensitivity in prediabetes. 120 participants would get injections. The sponsor is Hudson Biotech, recruiting at one hospital in Shenzhen.

It is fabricated.

On 31 July 2026 Morgan McSweeney published an investigation into eight registrations under that sponsor, all at the same site, all recruiting, all starting in February 2026. (Dr Noc) I ran the sponsor query and got the same eight. Three of them say what they are in their own text, the TB-500 record opening "This fictional study is an example of a ClinicalTrials.gov-style record." Two others copy Eli Lilly's internal protocol codes under a sponsor that is not Lilly, and Lilly confirmed to McSweeney it has no relationship with them.

The MOTS-c record confesses nothing. It cites real preclinical work and lays out a trial an ethics board would approve: four weeks of screening, then twelve weeks of treatment, blinded to participants and investigators both. Every tell sits outside the text. Both contact emails use a domain unrelated to the sponsor, and two supposedly different people have phone numbers differing in the last digit.

A registry mirror has already ingested it, and peptide blogs cite it as an ongoing human trial.

Now the real work, in mice, injected into the abdominal cavity.

Lee 2015. Male C57BL/6 mice got 5 mg per kg per day for seven days, in a study including a sugar tolerance test, an insulin clamp on a 60 percent fat diet, and young against middle aged males, six to eight per group. Another arm put CD-1 mice on a fattening diet and treated them with 0.5 mg per kg per day for eight weeks, ten per group, and the treated mice resisted weight gain. (PMID 25738459)

The longer arm used a tenth of the daily dose of the shorter one.

Reynolds 2021, the exercise study, in Nature Communications. One arm of 12 month old mice on a fattening diet compared 5 against 15 mg per kg per day for two weeks, and only the higher dose group ran significantly better. Another compared 15 mg per kg per day in 12 month old mice against 22 month old mice, roughly middle aged against elderly in human terms, and both groups ran about twice as long as untreated controls their own age. In the older comparison, 19 untreated animals against 18 treated, at a P value of 0.000002. That is the chance of a gap that size turning up by luck being about two in a million if the treatment did nothing. A final group started at about 24 months, too old to run, and got 15 mg per kg three times a week, with improvements in grip strength, stride length and a 60 second walking test. (PMID 33473109)

The lifespan claim is weaker than the headlines. In that oldest group, median and maximum survival rose by 6.4 percent and 7 percent, at P = 0.05, within a narrow window running to 31.8 months. The authors say larger cohorts will be needed.

Ten men on a bicycle. That same paper contains a human study routinely misreported as a MOTS-c trial. The men received no peptide at all. Ten sedentary young males, average age about 24, rode a stationary bicycle to exhaustion, and their own MOTS-c rose 11.9 fold in muscle and 1.5 fold in blood, returning to baseline within four hours.

That distinction is the one to hold on to. Measuring how much MOTS-c is already in somebody is a completely different kind of evidence from giving it to them and watching what happens.

The blood level studies contradict each other. An independent review by the Alzheimer's Drug Discovery Foundation counts about 14 of them. Some find MOTS-c declining with age and metabolic disease, others find it elevated in obesity. A 2025 study compared 22 lean adults with 32 obese adults awaiting bariatric surgery and followed 10 of the latter six months on. MOTS-c was higher in the obese group, 273 against 223 pg/mL, and the weight loss from surgery changed it not at all, P = 0.913. (PMID 41551324) These are antibody based assays for a tiny peptide, and readings vary by a factor of a thousand between reports.

Hard exercise raises it. Obesity raises it. Obesity resolved does not lower it. That is a smoke alarm going off before and after the fire, and you stop listening to the alarm.

A third kind of evidence comes from genetics. A single letter change in the mitochondrial DNA makes the peptide less active. It was linked to Japanese longevity by Fuku in 2015, but not in a later study of 736 people. Carriers had more fast twitch muscle fibres.

One human trial has completed, for a different molecule. NCT03998514, sponsored by CohBar, tested CB4211 in 88 people against placebo. CB4211 is a modified analogue rather than MOTS-c itself, and treating the two as the same thing is the fragment-versus-parent error this reference keeps running into. Its final cohort of 20 obese people with fatty liver got 25 mg once daily for four weeks, which is 2.5 to 5 times the dose people inject. The sponsor announced improvements in two liver enzymes and in glucose, with no serious adverse events, in a press release rather than a scientific paper. Injection site reactions are common across this class, and are a consequence of injecting.

The regulators moved anyway. In July 2026 the FDA's Pharmacy Compounding Advisory Committee voted to add MOTS-c to the list of substances a compounding pharmacy may lawfully use, 8 in favour, 6 against, 1 abstaining, over the objection of FDA's own reviewers, who found no clinical trials of the proposed uses at all. The vote is not binding, and any addition requires rulemaking, so MOTS-c is not on that list. It is on the 2026 World Anti-Doping Agency Prohibited List, banned at all times.

Where the dose came from

The convention is 5 to 10 mg per dose, two or three times a week up to daily, on 8 to 12 week cycles with 4 week breaks. It is a convention and not a finding. There is no approved labelling and no human dose finding trial.

Vendor and clinic pages say plainly that they arrived at the number by scaling the mouse doses by body surface area. I ran the same conversion on the 15 mg per kg dose that worked in older mice and it does not land at 5 to 10 mg. The route does not match either. Lee 2015 and Reynolds 2021 both injected into the abdominal cavity of rodents, humans inject under the skin, and no efficacy study in mice used that route.

What nobody knows

How long an injected dose lasts. Nobody has published a pharmacokinetic study in any species. Vendors give three different answers, and the four hour figure is usually credited to "the USC gerontology trials," which do not appear to exist.

What it binds to. No MOTS-c receptor has been identified, so nobody knows the target it acts on. The proposed mechanism is indirect: it inhibits the folate cycle, AICAR accumulates, and that activates AMPK, the cell's fuel gauge. None of this has been shown to happen in an injected human.

Why blood levels behave the way they do. Up with exercise, up again with obesity, and refusing to come down when the obesity is treated.

My thoughts

The fake record bothers me more than the missing evidence does. Eight forged registrations went into a government database, three of which admit they are examples, and the one that does not is getting cited as proof that human trials are under way. Until ClinicalTrials.gov explains how that got in and stayed in, I am going to treat an NCT number as a claim to check rather than a source, which is the opposite of how it actually gets used.

On the compound itself, my reading is that no trial of any kind has been run, not out of any particular caution about the peptide, but because it is an injection and nobody has fixed that.

If you have seen MOTS-c marketed with a mention of the 2026 human trial, where did you see it?

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This content is for educational and informational purposes only and is not medical advice. Peptides discussed are research compounds and may not be approved for human use. Nothing here should be used to diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare professional before starting any peptide, supplement, or protocol. Individual responses vary. Do not self-administer compounds without proper medical supervision.