MOTS-c Dosage Protocol & Weekly Timing: What’s Real vs. Cited
MOTS-c is a peptide the body already makes, encoded in mitochondrial DNA and released into circulation during exercise, which is why it's often called an "exercise mimetic." Mouse studies show it improves insulin sensitivity and prevents diet-induced obesity. What's missing is any human trial of MOTS-c itself: the FDA's own compounding review states it has "not identified any human exposure data" for MOTS-c "via any route of administration." The one real human trial in this space tested a different, patented molecule, not what's sold as MOTS-c.
Reviewed by the PepGuard team · Last reviewed Jul 28, 2026
Naturally occurring 16-amino-acid peptide encoded within the mitochondrial 12S rRNA gene · sometimes listed as Mitochondrial Open Reading Frame of the 12S rRNA-c, MOTS-C
Photo: Jorge Alberto Vega Barrera / UnsplashA weekly cycle, not a single dose.
Most searches are for a schedule (days on, days off, weeks per cycle), not a flat mg amount. Here’s what circulates, next to what’s actually been dosed in a study.
| What's cited | Range |
|---|---|
| Vendor-cited weekly total (no human trial exists for this) | 5-10 mg/week, subcutaneous |
| Vendor-cited daily cadence (no human trial exists for this) | 1-2 mg/day, 5 days on (Mon-Fri) / 2 days off |
| Vendor-cited cycle length (no human trial exists for this) | 8-12 weeks on, 4-6 week break |
| Actual published dose (mouse, insulin-sensitivity study) | 2.5 mg/kg, intraperitoneal, twice daily, 3 consecutive days (Kim et al. 2019) |
| Only human-tested dose of a MOTS-c-related molecule | 25 mg/day, subcutaneous, 28 days — but this was CB4211, a modified analog, not MOTS-c (CohBar Phase 1b, NCT03998514) |
The weekly "5 days on, 2 days off" cycling protocol that circulates in vendor and community content has no human trial behind it anywhere, consistent with the FDA's own statement that it has no human exposure data on MOTS-c at all. The only dosing regimen with a real study behind it is the mouse protocol from the peer-reviewed insulin-sensitivity research below, which is not a human dose and cannot be scaled to one. The 25 mg/day figure from the CB4211 trial is for a different, patented molecule, not MOTS-c, and is included here only to be transparent about what the "human trial" claims floating around actually refer to.
MOTS-c vs. CB4211: the human trial nobody mentions.
There is one real human clinical trial in the MOTS-c space: an 88-person Phase 1a/1b study (NCT03998514) run by the biotech CohBar, which reported reduced liver enzymes, lower glucose, and no serious adverse events after 28 days of daily dosing. The peptide tested was CB4211, a modified, patented analog CohBar engineered from MOTS-c, not MOTS-c itself.
That distinction gets lost constantly, both in casual conversation and in vendor marketing copy that cites CB4211’s results as if they applied to the unmodified peptide. They don’t. CB4211 is chemically distinct, was tested at a different dose (25 mg/day) than any vendor-cited MOTS-c protocol, and its safety data describes CB4211, not the molecule sold as MOTS-c.
Mostly borrowed from a different molecule.
| Signal | Frequency | Context |
|---|---|---|
| Injection site reaction (observed with the CB4211 analog, not MOTS-c itself) | commonly reported | Tracked as a safety endpoint in the CB4211 Phase 1a/1b trial. Since MOTS-c itself has never been dosed in a human trial, there is no equivalent safety data for the actual peptide sold by research-peptide vendors. |
| Serious adverse events (CB4211 analog trial) | rarely reported | CohBar reported CB4211 was well tolerated with no serious adverse events across the Phase 1a/1b program. Again, this describes a different molecule than MOTS-c. |
| Effects of self-administered MOTS-c in humans | unknown / not studied | Direct FDA quote: "FDA has not identified any human exposure data on drug products containing MOTs-C administered via any route of administration." |
| Immunogenicity from peptide-related impurities | unknown / not studied | FDA's compounding review flags this as a theoretical concern common to compounded peptides generally; antidrug antibody formation was a tracked outcome in the CB4211 trial, but that data describes the analog, not MOTS-c. |
| Long-term or cumulative effects of chronic/cyclical dosing | unknown / not studied | No human trial of any duration has tested MOTS-c itself. |
Not FDA-approved. FDA states it has no human exposure data for MOTS-c via any route.
MOTS-c has never been approved by the FDA for any use. It was nominated for the FDA's 503A "Category 2" bulk drug substance list (substances posing potential significant safety risks) and, after that nomination was withdrawn, came back before FDA's Pharmacy Compounding Advisory Committee at a July 23, 2026 meeting. FDA staff's stated reason for recommending against inclusion was direct and unusually blunt for a peptide on this site: "FDA has not identified any human exposure data on drug products containing MOTs-C administered via any route of administration. FDA lacks important information regarding any safety issues raised by MOTs-C, including whether it would cause harm when administered to humans." That's a stronger statement than the "limited data" language the agency used for several other peptides, it's a flat statement of zero human exposure data on file. The advisory panel didn't follow that recommendation: per independent reporting from NPR and CBS News, it voted, by a narrow margin, to recommend adding MOTS-c to the compounding list anyway, one of six peptides to receive a favorable vote that day. That's an advisory recommendation, not an FDA decision, and it doesn't change the underlying finding, zero human exposure data exists for MOTS-c itself. Separately, a modified analog of MOTS-c called CB4211, developed by the biotech CohBar and chemically distinct from MOTS-c itself, completed a Phase 1a/1b human trial (NCT03998514) for NAFLD and obesity in 2021. CB4211's results do not establish anything about MOTS-c's safety or effects in humans, since it is not the same molecule.
Every claim above, traced back.
Mechanistic studies, the CB4211 trial registry entry and its sponsor's own results, and the FDA's compounding record. Click through and check them yourself.
MOTS-c questions, answered.
No. That weekly cycling pattern, and the 5-10 mg/week totals that go with it, are vendor and community conventions with no published human study behind them. The FDA's own review of MOTS-c for compounding states it has "not identified any human exposure data" for MOTS-c "via any route of administration," which covers any dosing schedule, not just this one.
MOTS-c itself, no. The peptide that has been through a human trial is CB4211, a modified analog developed by the biotech CohBar, which completed a Phase 1a/1b study (88 participants, NCT03998514) and showed reductions in liver enzymes and glucose with no serious adverse events. CB4211 is chemically distinct from MOTS-c, so those results don't tell you what MOTS-c itself does or how safe it is in people.
MOTS-c is the naturally occurring 16-amino-acid mitochondrial peptide studied mostly in mice and cells. CB4211 is a separate, patented molecule that CohBar engineered to be "an improved analog" of MOTS-c for drug development, then tested in actual human trials. Vendors selling "MOTS-c" are not selling CB4211, and CB4211's human safety and efficacy data doesn't transfer to the unmodified peptide.
It's sold in the US as a research chemical, not an approved drug or supplement for human use. It was nominated for the FDA's 503A Category 2 compounding-restricted list and is currently listed as a withdrawn nomination, with the agency citing a complete lack of human exposure data as its concern. That's a regulatory gap, not a green light.
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