Compound Physician required WADA prohibited Part of Peptides

MOTS-c

Mitochondrial-derived peptide studied for metabolic effects. Early-stage research, minimal human data.

The story

MOTS-c exists because of a prior discovery that changed what mitochondrial DNA was thought to be for. The mitochondrial genome was long described as encoding 37 genes — 22 tRNAs, 2 rRNAs and 13 respiratory-chain proteins. In 2001, a group led by Yuichi Hashimoto in Tokyo, screening for factors that rescued neurons from familial Alzheimer's disease mutations, identified a short polypeptide they named humanin, encoded within the mitochondrial 16S rRNA region and secreted from cells (DOI 10.1073/pnas.101133498). Humanin established the category: the mitochondrion was a source of signaling peptides encoded in its own genome. If one such short open reading frame existed, others plausibly did.

MOTS-c was the answer to that question. Changhan David Lee, Pinchas Cohen and colleagues at the University of Southern California, searching mitochondrial DNA for additional short open reading frames, identified a 51-base-pair sORF inside the 12S rRNA gene encoding a 16-amino-acid peptide. They named it MOTS-c — mitochondrial open reading frame of the 12S rRNA-c — and reported it in Cell Metabolism in March 2015. The paper's claims were specific: skeletal muscle appeared to be the primary target organ; the cellular mechanism was inhibition of the folate cycle and its tethered de novo purine biosynthesis, causing accumulation of the endogenous AMP analog AICAR and consequent AMPK activation; and in mice, MOTS-c treatment prevented both age-dependent and high-fat-diet-induced insulin resistance as well as diet-induced obesity (DOI 10.1016/j.cmet.2015.02.009). An accompanying Cell Metabolism preview by Kim Zarse and Michael Ristow framed the finding as "an unexpected therapeutic option to be exploited toward the prevention of type 2 diabetes and delaying of the aging processes" (DOI 10.1016/j.cmet.2015.02.013) — the first appearance in print of the framing that would later carry the compound into consumer marketing.

Two further threads opened. The first was genetic: an East Asian–specific mtDNA variant, m.1382A>C, sits inside the MOTS-c reading frame and substitutes glutamine for lysine at residue 14 (K14Q); Fuku, Lucia, Hirose and colleagues proposed in Aging Cell that it might be one mechanism behind Japanese longevity (DOI 10.1111/acel.12389). The second was exercise. In 2021, Reynolds, Lee and Cohen reported in Nature Communications that MOTS-c improved physical performance in young, middle-aged and old mice, that late-life intermittent treatment increased physical capacity and healthspan, and — the human element — that exercise induced endogenous MOTS-c in human skeletal muscle and circulation (DOI 10.1038/s41467-020-20790-0). That paper is the hinge on which the "exercise mimetic" framing turns.

The commercial arc is short and ended without a drug. CohBar, Inc., a public company whose platform technology is described as based on Pinchas Cohen's research and on whose board Cohen sat (BioTuesdays, 2020), developed CB4211, which it described as "a novel and improved analog of MOTS-c," for NASH and obesity. A randomized, double-blind, placebo-controlled Phase 1a/1b trial of CB4211 in 88 subjects is registered under the name CohBar, Inc. and the record is marked completed (NCT03998514 — T2, registry record: existence and status only; verified against the ClinicalTrials.gov API 2026-08-29). Topline results were announced by press release in August 2021 (T3 — per sponsor announcement, GlobeNewswire); no figure from that announcement is reproduced here. The registry posting, the press release and the company's own pipeline descriptions are statements by a single entity and count as one source, not three. No results were posted to ClinicalTrials.gov and no peer-reviewed publication followed. In 2023 CohBar merged with Morphogenesis to form TuHURA Biosciences, which pivoted to immuno-oncology; the mitochondrial peptide programs, CB4211 included, were deprioritized (Fierce Biotech, 2023).

The route into consumer use is documented by the bodies that had to respond to it. USADA, explaining why MOTS-c was added to the 2024 WADA Prohibited List, wrote that it "is heavily marketed by wellness and anti-aging clinics and on social media as a weight loss peptide, even though it is an experimental peptide not approved for human therapeutic use" (USADA). The Los Angeles Times reported in August 2026 that Cohen himself — the discoverer — estimates "tens of thousands of people are injecting themselves with MOTS-c," and quotes him saying that is "black market, illegal, from unknown sources, unknown purity, unknown sterility, and I strongly object to that," while also arguing that regulated compounding is preferable to the status quo (LA Times via News-Tribune, 2026-08-18). In July 2026 an FDA advisory committee voted narrowly to recommend adding MOTS-c to the list of substances compounding pharmacies may use, over the objection of FDA's own scientists.

  1. 2001 Humanin identified — the first mitochondrial-derived peptide, establishing that mtDNA encodes signaling peptides
  2. 2015-03 Lee, Cohen and colleagues (USC) report MOTS-c in Cell Metabolism: 16-aa peptide from a 12S rRNA sORF; folate/purine–AICAR–AMPK mechanism; prevents diet-induced obesity and insulin resistance in mice. An accompanying preview frames it as a route to preventing type 2 diabetes and "delaying of the aging processes"
  3. 2015 Fuku et al. propose in Aging Cell that the East Asian–specific m.1382A>C (K14Q) variant in the MOTS-c reading frame contributes to Japanese longevity — a hypothesis paper, not an original cohort analysis
  4. 2018-07 A Phase 1a/1b trial of CB4211, a MOTS-c analog, is recorded as starting — registered under the name CohBar, Inc. — the first time anything in this peptide family entered a registered human trial
  5. 2021-01 Reynolds et al., Nat Commun: MOTS-c improves physical performance across mouse age groups and increases healthspan when started late in life; in humans, exercise raises endogenous MOTS-c in muscle and blood
  6. 2021-01 Zempo et al. report that male C-allele carriers of m.1382A>C have higher type 2 diabetes prevalence across three cohorts (n=27,527) — the opposite metabolic valence to the longevity hypothesis
  7. 2021-08 Positive topline Phase 1a/1b results for CB4211 are announced by press release — T3, per sponsor announcement, by the entity registered as the trial's sponsor; no outcome figure from it is carried anywhere in this dossier, it was never published in a peer-reviewed journal, and no results were posted to the registry
  8. 2023 CohBar merges with Morphogenesis to form TuHURA Biosciences; mitochondrial peptide programs deprioritized
  9. 2024-01-01 MOTS-c named on the WADA Prohibited List under S4, as an example of an AMPK activator; prohibited at all times
  10. 2026-07-23 FDA Pharmacy Compounding Advisory Committee votes 7–5 with 2 abstentions to recommend MOTS-c-related substances for the 503A Bulks List, against FDA staff's recommendation; non-binding

What it does

A mitochondrial-derived peptide studied for metabolic effects. Early-stage research with essentially no human outcome data — the mechanism story runs well ahead of the evidence.

A mitochondrial-derived peptide hypothesized to regulate metabolic homeostasis via AMPK activation, with proposed effects on insulin sensitivity and exercise adaptation.

  • metabolic regulation

What the evidence shows

The number of humans ever administered MOTS-c under study conditions is zero, by any route — FDA went looking for its July 2026 compounding review and reported it "did not include, and FDA did not identify, any clinical studies or human exposure data for MOTS-c via any route of administration," alongside no acute toxicity, genotoxicity, reproductive or carcinogenicity study in any species. The distinction that carries this file: everything that looks like human evidence is observational measurement of the body's own circulating MOTS-c as a marker of metabolic state, which is a different thing from giving the peptide to a person, and marketing conflates the two. Even that endogenous literature is qualified — it is almost entirely ELISA-based, and a validated WADA-standard mass-spectrometry method could not reproduce the ELISA reference range in the same healthy subjects. The animal work is genuinely interesting and internally consistent: MOTS-c prevented diet-induced obesity and insulin resistance in mice, and late-life intermittent treatment improved physical capacity and healthspan. That is also the limitation — the entire efficacy case is rodent, and no trial capable of changing that is known to exist.

Overall evidence strength: Very low certainty

  • Lee C, Zeng J, … Cohen P (2015) — the founding paper (2015) Preclinical / mechanistic

    Mice given MOTS-c did not get fat on a high-fat diet and did not become insulin resistant with age or overfeeding, apparently because the peptide blocks a step in folate metabolism, backing up an AMPK-activating molecule inside the cell. It shows nothing about effect in a person, at any dose, for any duration — every consumer claim about MOTS-c descends from this mouse paper.

    Source PMID 25738459

  • Reynolds JC, Lai RW, … Lee C (2021) — the "exercise mimetic" paper (2021) Preclinical / mechanistic

    Old mice given MOTS-c ran better and stayed functional longer, and separately, when humans exercise their own MOTS-c rises in muscle and blood. Those are two findings stapled together: the mice were given the peptide; the humans were only measured. No human in this study received MOTS-c.

    Source PMID 33473109

  • von Walden F, et al. (2021) — acute exercise and circulating MDPs (2021)

    A single 45-minute cycling session significantly raised circulating humanin, while MOTS-c showed only a trend that did not reach significance; resistance exercise moved neither. This is the most rigorous human exercise–MDP study in the literature, and its MOTS-c result is weaker than the way it is usually cited.

    Source PMID 34351816

  • Zempo H, Kim SJ, Fuku N, et al. (2021) — the m.1382A>C polymorphism (2021) Review / meta-analysis

    Men — not women — carrying the C allele had more type 2 diabetes, with the effect concentrated in the least physically active; in mice, MOTS-c improved glucose tolerance but the K14Q version did not. This is an association between a genetic variant and a disease in one population and one sex; nobody was given MOTS-c.

    Source PMID 33468709

  • Dieli-Conwright CM, et al. (2021) — exercise training and MOTS-c (2021)

    Four months of supervised exercise raised circulating MOTS-c in non-Hispanic White survivors but not Hispanic survivors, and where it rose it tracked with fat loss and better insulin resistance scores. The ethnic difference is unexplained, and the intervention was exercise, not MOTS-c.

    Source PMID 34413391

  • FDA briefing document on MOTS-c-related bulk drug substances (July 2026)

    The regulator went looking and reported what it found — no human data of any kind, no toxicity, genotoxicity, reproductive or carcinogenicity studies, a substance it considers "not well-characterized from the physical and chemical characterization perspective," and no outsourcing facility compounding it between January 2017 and December 2025 — concluding these factors "weigh against their being added to the 503A Bulks List."

    Source

  • The study that does not exist Preclinical / mechanistic

    That leaves the position FDA independently described in July 2026: it "did not include, and FDA did not identify, any clinical studies or human exposure data for MOTS-c via any route of administration" (FDA briefing document). No human being has been administered MOTS-c in any study, by any route, and no trial capable of changing that is known to exist. Every efficacy claim in circulation is an extrapolation from mice, and there is no pending readout that will change that. Where this dossier previously said "until it reads out," there is nothing to wait for.

    Source

Common misconceptions

“MOTS-c is an exercise mimetic — it delivers the benefits of exercise without the exercise.”

The direct answer first: administering MOTS-c to a human has never been shown to do anything, because it has never been studied. FDA searched in July 2026 and reported it "did not identify, any clinical studies or human exposure data for MOTS-c via any route of administration" (FDA). There is no human efficacy result to argue about, no human safety result, no human pharmacokinetic result. No trial capable of producing one is known to exist — a registry record asserting one was withdrawn from this dossier on 2026-08-29 as unverifiable. Where the framing came from. "Exercise mimetic" is not a marketer's coinage — it is used in the peer-reviewed literature, where MOTS-c is described as "a mitochondria-derived peptide that has been characterized as an exercise mimetic" (DOI 10.1016/j.bbagen.2021.130048) and as "being investigated as a potential exercise mimetic" (DOI 10.1016/j.mito.2023.06.002). It rests on two separate observations routinely welded into one claim: 1. Given to mice, MOTS-c produces exercise-like effects. Old mice ran better; late-life intermittent treatment increased physical capacity and healthspan (DOI 10.1038/s41467-020-20790-0); mice on a high-fat diet did not become obese or insulin resistant (DOI 10.1016/j.cmet.2015.02.009). This is real animal evidence and should not be dismissed. 2. In humans, exercise raises the body's own MOTS-c — and this is weaker than it is usually presented. Reynolds et al. report induction in muscle and circulation (DOI 10.1038/s41467-020-20790-0); a randomized study with a non-exercising control arm found a single endurance bout significantly raised humanin but produced only a non-significant trend for MOTS-c, with resistance exercise raising neither (DOI 10.1152/japplphysiol.00706.2019). Observation 2 concerns a peptide the body makes, measured in blood; observation 1 concerns a peptide injected into a rodent. Neither, nor both together, establishes that injecting MOTS-c into a person produces the effects of exercise. One human study found repeated heat exposure also raised circulating MOTS-c, "comparable to, but not identical to, exercise" (DOI 10.1249/mss.0000000000003825) — the peptide responds to several kinds of physiological stress, which is what a stress-responsive signal does, and is not evidence that the signal causes the benefit. Honest answer: the mechanism is genuinely interesting and the animal data genuinely suggestive. Whether MOTS-c does anything in a human is unknown — not "probably yes pending confirmation," and not "probably no." It is unstudied.

“MOTS-c is a proven longevity peptide — it extends lifespan and rejuvenates mitochondria.”

the mouse result is about healthspan, not lifespan — late-life intermittent treatment "can increase physical capacity and healthspan in mice" (DOI 10.1038/s41467-020-20790-0). Consumer material reports this as extended "healthy lifespan," drifting the claim toward survival (example as circulated). No human longevity, healthspan, functional-capacity or mortality outcome has ever been measured in anyone given MOTS-c. "Mitochondrial rejuvenation" is not a measured endpoint anywhere in the human literature; it is a mechanism description.

“The Japanese longevity variant proves MOTS-c drives longevity.”

this compresses findings that do not point the same way, and the most-cited source is not what it is taken to be. - Fuku et al., Aging Cell 2015, is a hypothesis piece, not an original cohort analysis: "we suggest that the m.1382A>C polymorphism … may be among the putative biological mechanisms explaining the high longevity of Japanese people," with the underlying longevity association attributed to earlier mtDNA haplogroup work on haplogroup D4b2 (DOI 10.1111/acel.12389). - The largest study of the same variant points the other way metabolically: across 27,527 Japanese adults, men carrying the C allele had higher type 2 diabetes prevalence, concentrated in the least physically active (DOI 10.18632/aging.202529). - Two further association studies find the C allele — which produces a less active MOTS-c — associated with more fast-twitch muscle and higher peak torque in Japanese men, and higher appendicular muscle mass and grip strength in older Korean men (DOI 10.1016/j.bbagen.2021.130048; DOI 10.3390/biomedicines12102384). ⚠️ Unresolved. These do not assemble into "more MOTS-c is better." Every one is an association in a cohort, in East Asian populations, with no intervention and no MOTS-c administered to anyone.

“You can measure your MOTS-c level to see how your mitochondria are doing.”

essentially the entire human MOTS-c literature rests on commercial ELISA kits, and the one study that checked those kits against a validated mass-spectrometry method could not reproduce them. Developing a doping-control assay, Knoop et al. validated an LC/MS method to WADA's International Standard for Laboratories (limit of detection 100 pg/mL), then compared it against a commercial ELISA in 20 healthy subjects: "endogenous levels of a reference population of 20 healthy subjects studied by ELISA experiments (45.9–218.5 ng/mL) could not be confirmed by LC/MS" (DOI 10.1002/rcm.8337). ⚠️ Unresolved, and consequential. That is a roughly three-orders-of-magnitude discrepancy between two methods for the same analyte, unresolved in the published literature. It does not prove the ELISA findings wrong, but no circulating MOTS-c number — from a study or a consumer panel — should be treated as an established quantity. Carried into.

“It's a peptide your body already makes, so it's safe.”

MOTS-c is unambiguously endogenous — its coding sequence is a known mitochondrial short open reading frame — but endogeneity has never established safety at pharmacological exposure. FDA found no acute toxicity, genotoxicity, reproductive toxicity or carcinogenicity data in any species, and stated that "MOTS-c is a peptide containing 16 amino acids for which there is a lack of information to assess its immunogenic safety risk" (FDA). USADA reports that side effects described by online purchasers include increased heart rate, palpitations, injection-site irritation, insomnia, immune reactions and fever, and that "it is unknown under what conditions (if any) it is safe to use MOTS-c because there are no completed human clinical trials" (USADA).

“There have been human trials — CB4211 was in Phase 1.”

CB4211 is not MOTS-c; the entity its trial is registered under described it as "a novel and improved analog of MOTS-c" (T3 — per sponsor announcement, company release). A randomized placebo-controlled Phase 1a/1b in 88 people is registered under the name CohBar, Inc. and the record is marked completed (NCT03998514 — T2, existence and status only). Three limits: the efficacy portion allocated 11 people to drug against 9 on placebo over four weeks; results were announced by press release — T3, per sponsor announcement, by that same single entity, so the posting, the release and the pipeline pages are one source and not three — and never peer-reviewed, with none posted to the registry; and the program was abandoned when the sponsor merged into an oncology company in 2023 (Fierce Biotech). ---

Who it's for, who should skip

Experimental only. Status is gray_zone — PCAC-recommended but unlawful pending rulemaking; research-stage, no standardized human protocol. Human outcome evidence is essentially absent.

Running it

No dosing protocol is published for this compound — there is no lawful supervised channel for the use this guide covers. What follows is monitoring, expectations, and safety framing only.

Form
injectable

What to expect

  • Onset (days) — Nothing measured in humans. In mice, seven days of administration restored insulin sensitivity in aged animals (DOI 10.1016/j.cmet.2015.02.009) (Confidence: Preclinical only)
  • Onset (weeks) — Clinic marketing describes improved energy, endurance, recovery and body composition "within 4–8 weeks" (Lamkin Clinic). No human trial of any duration supports this (Confidence: Anecdotal, low confidence)
  • Plateau — Not studied in humans. No human dose-response or duration-response experiment exists at all (Confidence: No data)
  • Duration of effect — Not studied in humans. FDA identified one in vitro study showing rapid degradation of the peptide in human blood, which speaks to clearance, not to duration of any effect (FDA) (Confidence: No data)
  • Post-cessation — Not studied in any species for the relevant question (Confidence: No data)
  • Long-term — No study in any species has assessed chronic toxicity, carcinogenicity or reproductive effects (FDA) (Confidence: No data)
  • Circulating MOTS-c after exercise (endogenous, not administered) — A single endurance bout produced a non-significant trend; 16 weeks of training raised levels in one ethnic subgroup and not another; two weeks of repeated heat exposure raised levels (Confidence: Trial-documented, endogenous only (DOI 10.1152/japplphysiol.00706.2019; DOI 10.1038/s41598-021-96419-z; DOI 10.1249/mss.0000000000003825))
  • First real answer expected — No credible pending readout identified. No study administering MOTS-c to humans is known to be underway; the registry record that formerly stood here was withdrawn on 2026-08-29 as unverifiable (Confidence: No data)

Response signs

Likely working

  • Improved energy, endurance, recovery, body composition over 4–8 weeks — Anecdotal, low confidence — the marketed expectation, with no human trial support of any kind · Lamkin Clinic Anecdotal
  • Improved exercise capacity — Preclinical only — demonstrated in mice across three age groups; never in a human given the peptide · DOI 10.1038/s41467-020-20790-0 Preclinical
  • Improved glucose tolerance / insulin sensitivity — Preclinical only — mice on a high-fat diet and aged mice; no human has been given MOTS-c and measured · DOI 10.1016/j.cmet.2015.02.009 Preclinical

Adverse — seek review

  • Increased heart rate or palpitations; insomnia — Anecdotal, low confidence — reported by online purchasers as compiled by USADA; never in a clinical study · USADA Anecdotal
  • Fever or immune reaction after a dose — Anecdotal, but note FDA's stated inability to assess immunogenicity risk for this peptide — an immune reaction is the mechanistically plausible version of this sign · USADA; FDA Anecdotal
  • Injection-site irritation, particularly spreading, warm or persisting — Anecdotal, low confidence for MOTS-c. The entity the analog CB4211's trial is registered under described injection-site reactions in its Phase 1 (T3 — per sponsor announcement) — a different molecule, noted for context only, and no figure of any kind is carried with it. The adverse-event rate that formerly appeared here has been removed: it rested solely on a company press release, and under R-C a T3 source may never carry a safety figure; one would need a T1 peer-reviewed publication or posted registry results · USADA; company release Anecdotal
  • Any systemic reaction after a dose from a non-pharmacy source — Inference, not documented for MOTS-c. Flagged because the discoverer describes the supply as "from unknown sources, unknown purity, unknown sterility" · LA Times via News-Tribune Inference

Common / neutral

  • No perceptible subjective effect at all — Consistent with the published record: no documented acute perceptual signature in humans, and no human pharmacodynamic study exists · FDA

Getting it right

  • Monitoring: There is no efficacy biomarker to monitor. Nothing validated predicts or confirms a response to administered MOTS-c. Any monitoring plan is safety monitoring, not effectiveness monitoring. mitigate side effect
  • Monitoring: A circulating MOTS-c level is not a monitoring tool. The assay used across the human literature could not be confirmed against a validated mass-spectrometry method (DOI 10.1002/rcm.8337), and no reference range for someone receiving exogenous peptide exists at all. mitigate side effect
  • Monitoring: The baseline advice that stood here has been removed, and not replaced. A bullet named OGTT-derived insulin sensitivity, HbA1c, fasting glucose and lipids as what to baseline. Its only justification was that a registered trial had chosen those endpoints, and that registry record has been withdrawn from this dossier as unverifiable. The rationale was the trial. Nothing in the sourced record supports singling out those particular tests for someone using MOTS-c, and no substitute rationale has been invented. mitigate side effect
  • Monitoring: There is no observed safety window in any species. FDA found no acute or chronic toxicity, genotoxicity, reproductive or carcinogenicity studies (FDA). Open-ended use sits outside the observed window of every study ever conducted. mitigate side effect
  • General safety: Product identity and sterility dominate, ahead of pharmacology. The discoverer describes the supply as "black market, illegal, from unknown sources, unknown purity, unknown sterility" (LA Times via News-Tribune). FDA separately found the substance itself "not well-characterized from the physical and chemical characterization perspective," with missing data on aggregation, microbial bioburden and bacterial endotoxin (FDA) — the parameters that drive injection-site and systemic reactions. mitigate side effect
  • General safety: Immunogenicity cannot currently be assessed. FDA said so explicitly for this peptide. mitigate side effect
  • General safety: Combination use compounds the unknowns. No stack containing MOTS-c has been tested against its components; an adverse event in a multi-compound regimen cannot be attributed to anything. mitigate side effect
  • General safety: Athletes and service members face strict liability. MOTS-c is named on the WADA Prohibited List and on the DoD prohibited list. Intent and ignorance do not mitigate. mitigate side effect
  • The physician conversation: What is the actual goal — fat loss, glycaemic control, endurance, "longevity" — and what would count as it working, by when? (Each has an intervention with randomized human evidence; MOTS-c has none.) mitigate side effect
  • The physician conversation: Has metabolic status actually been measured at all, by whatever workup the clinician judges appropriate, or is the goal being pursued without a baseline? (This question named four specific tests until 2026-08-29. The enumeration has been removed: the only thing in this file that ever justified singling out those particular tests was the endpoint list of a registry record since withdrawn on provenance grounds, and the parallel baseline advice was removed for exactly that reason. Asking whether a baseline exists survives; telling a reader which baseline does not.) mitigate side effect
  • The physician conversation: What else is being taken, including anything from a non-pharmacy source, and what is in each vial according to whom? mitigate side effect
  • The physician conversation: Is there any competitive sport, collegiate, or military testing obligation? (— this is a named prohibited substance, not a gray area.) mitigate side effect
  • The physician conversation: What is the plan if nothing measurable changes — and who decides when to stop? mitigate side effect

Safety

  • minimal human safety data; supplier-quality concerns; long-term effects uncharacterized

Stacking & alternatives

  • Complements SS-31 (Elamipretide) — The natural in-batch comparator and the compound MOTS-c is most often paired with in marketing. Mechanistically distinct: elamipretide stabilizes cardiolipin in the inner mitochondrial membrane; MOTS-c signals through folate/purine metabolism to AMPK (DOI 10.1016/j.cmet.2015.02.009)

Access & cost

Legally unsettled. Access, where it exists at all, runs through a physician — not a consumer purchase. See the status note above.

No lawful channel to price. As of 2026-08-28 there is no lawful US route to obtain MOTS-c for human use: it is not an FDA-approved drug, it is not on the 503A Bulks List, and FDA's review found no outsourcing facility reported compounding it between January 2017 and December 2025 (FDA). There is therefore no legitimate pharmacy, telehealth or brand price to report. A gray market nonetheless exists and has been documented by mainstream reporting: the Los Angeles Times describes MOTS-c as widely available online, often in vials marked "for research use only," through unregulated online marketplaces, with the compound's discoverer estimating that tens of thousands of people are self-injecting it (LA Times via News-Tribune). No INTERNAL subsection appears here. We found no journalist-reported specific price figures for MOTS-c. Nothing has been withheld; nothing publishable exists to withhold. ---

Questions

Does MOTS-c actually work?
For any human outcome, nobody knows: it has never been tested in a human (FDA). What exists is a consistent mouse literature — prevention of diet-induced obesity and insulin resistance, improved physical capacity in old animals (DOI 10.1016/j.cmet.2015.02.009; DOI 10.1038/s41467-020-20790-0). No randomized placebo-controlled human trial of MOTS-c is known to exist, and none is known to be pending.
Is MOTS-c really "exercise in a bottle"?
That phrase is marketing; the underlying scientific label, "exercise mimetic," describes a mouse phenotype plus a human correlation, not a human result. The Los Angeles Times quotes the peptide's own discoverer on how the claim propagates: certain groups "take one figure from one paper done on mice and take it to become gospel" (LA Times via News-Tribune).
Oral, nasal or injectable — which form works?
None has been compared to another in a human, and none has been shown to reach the bloodstream in a human; there is no published human pharmacokinetic study by any route. The 503A nomination proposed subcutaneous injection only, and FDA observed that "it appears that compounded MOTS-c is marketed alone and in combination with other substances as injectable formulations" (FDA). FDA also identified an in vitro study showing rapid degradation of the peptide in human blood — which makes any oral or transmucosal absorption claim something that would have to be demonstrated, not assumed. Treat oral-vs-injectable claims in either direction as marketing.
Does MOTS-c help you lose weight?
In mice on a high-fat diet, yes — that is the founding result (DOI 10.1016/j.cmet.2015.02.009). In humans there is no weight-loss data of any kind. USADA notes it "is heavily marketed by wellness and anti-aging clinics and on social media as a weight loss peptide, even though it is an experimental peptide not approved for human therapeutic use" (USADA). No human trial has measured weight, or anything else, in a person given MOTS-c.
Is MOTS-c safe?
Unknown, and the gaps are specific. FDA found no acute toxicity, genotoxicity, reproductive or carcinogenicity studies in any species, considers the substance not well-characterized physicochemically, and flagged an unassessable immunogenicity risk (FDA). USADA lists side effects reported by online purchasers — raised heart rate, palpitations, injection-site irritation, insomnia, immune reactions, fever — and states there are no completed human clinical trials (USADA). Those reports are anecdotal, low confidence.
Will MOTS-c make me fail a drug test?
It is named on the WADA Prohibited List and prohibited at all times, and a validated plasma detection method exists (USADA; DOI 10.1002/rcm.8337). See.
Can I just get my MOTS-c level tested, and what happens when I stop?
The assay's meaning is contested — a validated mass-spectrometry method could not reproduce commercial ELISA values in the same healthy subjects (DOI 10.1002/rcm.8337) — and nothing at all is documented about cessation, in any species, for any outcome. ---

Last reviewed 27 August 2026. Regulatory status verified 27 August 2026.