Retatrutide with MOTS-c: no study has combined them, a trialled triple agonist next to a peptide with no human dosing data, what each record shows, and units.
Retatrutide with MOTS-c is searched as a pairing of the strongest weight-loss peptide in trials with a "mitochondrial" peptide sold for metabolism and muscle. The two records could hardly differ more. Retatrutide has a phase 3 programme with thousands of participants. MOTS-c has mouse studies, cell studies and one registered human trial with no dose in it. Nothing at all has been published on the two together.
The single-compound records are on the retatrutide and MOTS-c dosage pages. Retatrutide's comparison with another weight-loss peptide is on cagrilintide vs retatrutide, and its time in the body on retatrutide half-life.
The registry, counted
ClinicalTrials.gov returned zero records naming both retatrutide and MOTS-c as interventions on 2026-10-09, and PubMed zero records for the pair. ClinicalTrials.gov's search for MOTS-c returned nine records: one administers it, the Hudson Biotech registration NCT07505745, which describes a fixed daily dose under the skin for 12 weeks in 120 adults with prediabetes and overweight without stating a milligram figure; the rest measure the body's own MOTS-c in blood, or do not concern it.
What each record holds
|
Retatrutide |
MOTS-c |
| What it is |
GIP, GLP-1 and glucagon receptor agonist |
16-amino-acid peptide encoded in mitochondrial DNA |
|---|
| Approved product |
None; Lilly plans to file in early 2027 |
None |
|---|
| Human trials |
Phase 2 (338 adults) and TRIUMPH phase 3 |
One registered, no dose stated, no results |
|---|
| Trial doses |
1–12 mg weekly; phase 3 at 4, 9, 12 mg |
None in people |
|---|
| Weight result |
−19.0% to −28.3% at 80 weeks (TRIUMPH-1, company release) |
Mouse studies only |
|---|
| FDA bulk-substance list |
Not listed |
Category 2 from 2023, withdrawn nomination by 2026-04-22; advisory vote 7 to 5 in favour of inclusion, July 2026 |
|---|
The idea behind the stack, and its limits
The usual case for the pairing has two parts: retatrutide takes weight off, and MOTS-c, which made mice behave metabolically as if they had exercised, keeps muscle and insulin sensitivity while it does. The first part is a trial result. The second is an animal result: the original 2015 study (Lee et al., Cell Metabolism) and later work used mice and rats at doses such as 5 to 15 mg/kg, figures that have never been given to people.
Two studies touch the space between the compounds, and neither tests the stack. In cell lines, MOTS-c lowered insulin secretion from rat beta cells and raised glucagon secretion from mouse alpha cells (Bień et al., 2024). Retatrutide is itself a glucagon receptor agonist, so the cell result points to an overlap that nobody has measured in a person, not to a benefit. And in 163 people with type 2 diabetes followed for 12 months, the body's own MOTS-c rose on empagliflozin, alone or with liraglutide, but not on liraglutide alone (Ikonomidis et al., 2025). That is an observational measurement of a hormone the body makes, in people who did not receive MOTS-c, and liraglutide is a GLP-1 drug, not retatrutide.
| Figure |
Source |
Molecules |
| Retatrutide 2 mg weekly |
Trial starting step |
— |
| Retatrutide 4 / 9 / 12 mg weekly |
TRIUMPH maintenance doses |
— |
| MOTS-c 5 mg |
Vendor pages, per injection |
≈2.3 µmol |
| MOTS-c 5–10 mg a week |
Vendor pages, over 2–3 injections |
≈2.3–4.6 µmol |
| CB4211 25 mg daily |
A different molecule (CohBar), 4 weeks |
Does not transfer |
PubChem returned no compound record for retatrutide by name on 2026-10-09, so its doses are shown in milligrams only. Community pages also circulate retatrutide starting figures of 0.25 to 0.5 mg a week, below every trial arm, as recorded on the retatrutide page; no source ties any of these figures to the combination.
Reconstitution and the units per draw
| Amount |
5 mg/mL |
10 mg/mL |
20 mg/mL |
| Retatrutide 2 mg |
40 units |
20 units |
10 units |
| Retatrutide 4 mg |
80 units |
40 units |
20 units |
| Retatrutide 12 mg |
240 units |
120 units |
60 units |
| MOTS-c 2.5 mg |
50 units |
25 units |
12.5 units |
| MOTS-c 5 mg |
100 units |
50 units |
25 units |
| MOTS-c 10 mg |
200 units |
100 units |
50 units |
5 mg/mL is a 5 mg vial with 1 mL or a 10 mg vial with 2 mL; 10 mg/mL is a 10 mg vial with 1 mL; 20 mg/mL is a 20 mg vial with 1 mL. Several of these draws fill or overflow a 100-unit syringe at the more dilute concentrations. Each compound is drawn from its own vial; no label or study describes mixing the two. Any vial and volume are worked on the retatrutide calculator and the MOTS-c vial and dose arithmetic.
No human study has given retatrutide and MOTS-c together, and MOTS-c has never had a published dose in a person, so the stack has no measured effect, no safety record and no dose. Retatrutide's phase 3 figures are from company releases; its discontinuation for side effects rose with dose in TRIUMPH-1, from 4.1% on 4 mg to 11.3% on 12 mg against 4.9% on placebo. Neither compound is approved. The compounds are covered in Medibact's Retatrutide guide and MOTS-c guide. Nothing on this page is an instruction; product and dose belong with a prescriber.
Sources and dates
Opened 2026-10-09: ClinicalTrials.gov searches (retatrutide AND MOTS-c, 0; MOTS-c, 9 records, each read); PubMed searches for the pair (0) and for MOTS-c with incretin terms (4 records); the abstracts of Bień et al. 2024 (PMID 38430258) and Ikonomidis et al. 2025 (PMID 40008510); the PubChem record for MOTS-c (CID 146675088). Carried from this site's pages, each with its read date: the retatrutide phase 2 and TRIUMPH figures and community figures (retatrutide page, 2026-09-18), and MOTS-c's registry, CB4211, animal doses, vendor figures and FDA status (MOTS-c page, 2026-09-18). Units and molar arithmetic by this site. Corrections go to the contact page.
