Reviewed evidence dossier / MOTS-01
MOTS-c evidence:
endogenous is not exogenous.
Human studies have measured MOTS-c produced within the body, while intervention findings come from cell systems and animals. This dossier keeps those evidence types separate and treats FDA’s July 2026 compounding assessment as a proposal—not a final agency decision.
Distinct cellular, animal, and human observations.
The cited sources establish a mitochondrial-derived peptide research identity, cell and mouse findings, and endogenous MOTS-c measurements in defined human cohorts.
A human therapeutic outcome.
The record does not establish safety, effectiveness, pharmacokinetics, performance effects, longevity, product approval, or catalog-vial equivalence for exogenous MOTS-c in people.
What kind of answer can this dossier provide?
MOTS-c is described as a 16-amino-acid mitochondrial-derived peptide encoded within the mitochondrial 12S rRNA region. Published human research cited here measures MOTS-c produced within the body. Separate laboratory and mouse experiments examine exogenous exposure. Combining those records into a single “human treatment” conclusion would erase the most important evidence boundary.
The source of a measured peptide changes the question.
PubChem records human MOTS-c under CID 155885767. FDA’s 2026 briefing separately evaluates MOTS-c free base and MOTS-c acetate as distinct bulk drug substances and notes naming and characterization uncertainties. A database identity or endogenous human measurement does not verify a separate material.
Detecting or measuring MOTS-c that the body produces is evidence about endogenous physiology. It is not evidence that an externally supplied MOTS-c material has the same exposure, pharmacokinetics, safety, or effects in people.
Finding, model, limitation, source.
MOUSE MODELS
Foundational metabolic experiments
The 2015 report identified MOTS-c and described pathway observations in cultured cells together with metabolic findings in mouse models.
Limit: Cell signaling and mouse outcomes do not establish effectiveness, safety, or pharmacokinetics of an exogenous material in people.
HUMAN DATA
Exercise-associated measurements in ten young men
A 2021 study reported changes in endogenous skeletal-muscle and circulating MOTS-c after exercise in ten young male participants. The same paper separately reported cell and mouse intervention experiments.
Limit: Measuring an endogenous response to exercise is not a human trial of externally supplied MOTS-c and does not establish a performance effect.
OBSERVATIONAL
Age, muscle expression, and associations
A study of healthy men in three age groups measured circulating and skeletal-muscle MOTS-c and reported age- and muscle-fiber-related associations.
Limit: Observational associations do not establish causality, a treatment effect, or the effects of an exogenous peptide.
HUMAN GAP
No identified human drug-product exposure record
FDA’s July 2026 briefing states that it did not identify clinical studies or human exposure data for MOTS-c-related bulk drug substances by any route and therefore could not characterize potential human safety risks.
Limit: Absence of identified exposure data does not prove either safety or harm. It identifies an evidence gap.
ASSESSMENT
Characterization, aggregation, impurity, and immunogenicity questions
FDA’s briefing identifies uncertainties involving free-base versus acetate identity, critical characterization information, potential aggregation, peptide-related impurities, and immunogenicity.
Limit: These are FDA-identified potential risks and unresolved questions; the record does not quantify their incidence or evaluate a specific commercial vial.
PROPOSAL
July 2026 materials are not a final determination
FDA’s briefing says the evaluation criteria weighed against adding MOTS-c free base or acetate to the 503A Bulks List and presented that position for advisory-committee consideration.
Limit: FDA explicitly states that it will not make a final determination until advisory input has been considered and reviews are finalized.
Questions the cited record does not resolve.
Endogenous blood and muscle measurements do not establish exposure, pharmacokinetics, safety, or effectiveness of an externally supplied material.
The core sources do not establish human metabolic, performance, aging, cardiovascular, bone, or longevity outcomes from exogenous MOTS-c.
Free base, acetate, and other records cannot be treated as interchangeable without exact identity and characterization evidence.
A name, sequence, or publication does not establish identity, purity, strength, safety, efficacy, approval, or intended use for a seller’s material.
Endogenous measurement is not exogenous treatment.
What is MOTS-c?
MOTS-c is a 16-amino-acid mitochondrial-derived peptide described as encoded within the mitochondrial 12S rRNA region. PubChem records a human MOTS-c reference under CID 155885767.
Has MOTS-c been studied in humans?
Published human studies have measured MOTS-c produced within the body, including exercise-associated blood and skeletal-muscle measurements and observational measurements across age groups. Those are not trials of an exogenous MOTS-c drug product.
What did the exercise study show in its human participants?
It reported changes in endogenous skeletal-muscle and circulating MOTS-c after exercise in ten young men. The paper’s experiments involving externally supplied MOTS-c were conducted separately in cell and mouse models.
Do mouse performance findings establish a human performance effect?
No. Mouse intervention experiments and endogenous human measurements are different evidence types. Neither establishes a human performance effect from an exogenous MOTS-c material.
What human exposure data did FDA identify for MOTS-c drug products?
FDA’s July 2026 briefing states that it did not identify clinical studies or human exposure data for MOTS-c-related bulk drug substances by any route. FDA therefore described potential human safety risks as unknown.
Is FDA’s July 2026 assessment a final decision?
No. The briefing describes FDA’s assessment and proposal for advisory-committee consideration. FDA states that a final determination follows consideration of advisory input and completion of its reviews.
Does this dossier evaluate any PSC catalog vial?
No. A reference identity, endogenous measurement, or published model does not establish the identity, purity, strength, safety, efficacy, approval, or intended use of a seller’s material.
Open the exposure type with the finding.
- PubChem · Human MOTS-cChemical-identity record, CID 155885767. Identity context only; not a commercial-material test.PubChem record ↗
- Lee et al. · Cell Metabolism · 2015Foundational cellular and mouse metabolic experiments · PMCID PMC4350682 · DOI 10.1016/j.cmet.2015.02.009.PubMed 25738459 ↗
- Reynolds et al. · Nature Communications · 2021Endogenous exercise-associated measurements in ten young men, with separate cell and mouse intervention experiments · PMCID PMC7817689 · DOI 10.1038/s41467-020-20790-0.PubMed 33473109 ↗
- D’Souza et al. · Aging · 2020Observational circulating and skeletal-muscle measurements in healthy men across three age groups · PMCID PMC7138593 · DOI 10.18632/aging.102944.PubMed 32182209 ↗
- FDA Pharmacy Compounding Advisory Committee briefing · July 2026Agency assessment of free-base and acetate identity, nonclinical evidence, quality, human-exposure gaps, potential safety concerns, and a proposed recommendation. Not a final determination.FDA briefing PDF ↗
- FDA compounding safety-risk summaryLive agency page describing lack of identified human drug-product exposure data and potential immunogenicity, impurity, and characterization concerns.FDA record ↗
- FDA Pharmacy Compounding Advisory Committee meeting record · July 2026Official meeting materials and the boundary that advisory recommendations are nonbinding.FDA meeting record ↗
Versioned, not silently rewritten.
Version 1.0 published. Separated endogenous human measurements from exogenous cell and animal experiments, added identity and exposure boundaries, and labeled FDA’s July 2026 assessment as a proposal rather than a final decision.
A substantive correction records the date, changed statement, reason, and supporting source. Send a precise citation or correction request through the PSC policies and contact page.