CB4211 vs MOTS-c compared: origin, structure, research stage, half-life, and legal status, plus what early studies actually show for each compound.
CB4211 and MOTS-c are closely related, but they are not interchangeable. CB4211 is a synthetic, stabilized analog of MOTS-c that was developed as an experimental drug for fatty liver disease and obesity, while MOTS-c is the naturally occurring 16-amino-acid mitochondrial peptide that inspired it. The practical difference is that CB4211 reached human clinical trials and was later discontinued, whereas MOTS-c remains a laboratory research peptide with no approved human use.
What Is MOTS-c?
MOTS-c is a 16-amino-acid peptide encoded inside the 12S ribosomal RNA region of mitochondrial DNA, which means its genetic instructions sit outside the cell nucleus. Researchers first described it in 2015 and group it with the mitochondrial-derived peptides, sometimes called mitokines because it leaves the mitochondria and signals to tissues elsewhere in the body.
Laboratory and animal work links MOTS-c to several metabolic pathways:
- AMPK activation, the cell's main energy-sensing switch
- Insulin sensitivity and glucose uptake in skeletal muscle
- Folate and methionine metabolism
- Exercise capacity and age-related metabolic decline
Circulating MOTS-c levels in humans are low and appear to fall with age, which is a big reason the peptide attracts attention in longevity and metabolic research. Human data is mostly observational, meaning it measures natural levels rather than testing the peptide as a treatment.
What Is CB4211?
CB4211 is a synthetic analog of MOTS-c, chemically modified to resist enzymatic breakdown and stay intact longer after injection. It was developed by CohBar, Inc. as an investigational drug for nonalcoholic steatohepatitis (NASH) and obesity, and it was given as a once-daily subcutaneous injection during clinical testing.
In a Phase 1b trial in adults with obesity and fatty liver, CB4211 was reported to reduce liver fat and body weight compared with placebo over a short treatment window. That result made it one of the very few mitochondrial-derived peptide candidates ever tested in humans.
Development stopped. CohBar wound down its operations in 2023, so CB4211 is not commercially available and has no approved use anywhere.
CB4211 vs MOTS-c: Side-by-Side Comparison
| Feature | MOTS-c | CB4211 |
|---|---|---|
| Chemical identity | Naturally occurring 16-amino-acid mitochondrial peptide | Synthetic, stabilized analog of MOTS-c |
| Origin | Encoded in mitochondrial 12S rRNA | Engineered in a laboratory by CohBar |
| Human clinical data | Observational blood-level studies only | Phase 1b trial in obesity and fatty liver |
| Administration in research | In vitro and animal protocols | Once-daily subcutaneous injection in trials |
| Stability | Short circulating half-life, rapid enzyme breakdown | Modified for a longer half-life |
| FDA status | Not approved for human use | Not approved; development discontinued |
| Availability today | Sold as a research chemical only | Not available for purchase |
What the Research Shows
MOTS-c studies
Animal studies report that MOTS-c treatment improves insulin sensitivity and exercise tolerance, while mice lacking the peptide show signs of accelerated metabolic aging. Nearly all of this work is preclinical, so the findings describe biology rather than a proven human therapy.
CB4211 trials
CB4211's human data comes from a small, short Phase 1b study, which is designed mainly to check safety and early signals rather than to confirm effectiveness. The liver-fat and body-weight improvements were encouraging enough to justify further study, but a larger Phase 2 trial never took place.
CB4211 is the only compound in this pair with human clinical data, and that data is early-stage and was never confirmed in a larger trial.
Half-Life and Stability Differences
Native MOTS-c has a short circulating half-life and is quickly degraded by plasma enzymes, which complicates both laboratory research and any theoretical therapeutic use. CB4211 was engineered specifically to solve that problem, which is why it could be dosed once daily in a clinical trial instead of repeatedly.
That difference matters when reading the literature: results from a stabilized analog do not automatically transfer to the native peptide, and results from the native peptide do not automatically transfer to the analog.
Legal Status, Availability, and Safety
Neither CB4211 nor MOTS-c is FDA-approved for human use in the United States. MOTS-c is sold by research chemical suppliers with research-use-only labeling, and CB4211 has no consumer market at all because its development was discontinued.
Unapproved peptides carry real risks, including uncertain purity, dosing errors, injection-site reactions, and unknown long-term effects. Anyone considering use outside a laboratory should speak with a licensed healthcare professional, and researchers should rely on third-party certificates of analysis covering purity, identity, and endotoxin levels.
Related Compounds Researchers Compare
MOTS-c is rarely studied in isolation. Metabolic researchers often line it up against other mitochondrial and lipolytic compounds, and comparisons such as mots-c vs aod9604 and aicar vs mots-c appear often in the same literature.
Newer entries include slu-pp-332 vs mots-c and nad plus vs mots c, both of which lean toward cellular energy metabolism rather than mitochondrial hormone signaling. On the incretin side, reta vs mots-c is a common search even though those two compounds work through completely different pathways.
The Bottom Line
If the question is which compound is further along, CB4211 wins on paper because it was tested in humans, but the program is dead and the product cannot be purchased. MOTS-c is the commercially available research peptide, yet it has no approved human trials to support any therapeutic claim.
For research purposes, treat them as two distinct molecules that share a parent sequence. CB4211 is a stabilized MOTS-c analog; MOTS-c is a mitochondrial signaling peptide with a short half-life and a preclinical evidence base.
Frequently Asked Questions
Is CB4211 the same thing as MOTS-c?
No. CB4211 is a synthetic analog of MOTS-c that was chemically modified to resist breakdown and last longer in the body, while MOTS-c is the naturally occurring 16-amino-acid peptide encoded in mitochondrial DNA. The two share a common origin but differ in stability, development history, and availability.
Is MOTS-c FDA-approved for human use?
No. MOTS-c is not FDA-approved for human use in the United States, and vendors sell it strictly as a research chemical labeled not for human consumption. No approved human trials have established safe dosing or long-term effects, so anyone considering it should consult a licensed healthcare professional.
What happened to CB4211?
CB4211 was developed by CohBar, Inc. and tested in a Phase 1b trial in adults with obesity and fatty liver, where it was reported to reduce liver fat and body weight. The company wound down operations in 2023 and the program was discontinued, so CB4211 is not available for purchase and is not FDA-approved.
This page provides educational research information and does not replace medical advice, diagnosis, or treatment.