Comparison
Two mitochondrial peptides at opposite ends of the evidence pipeline.
MOTS-c is a mitochondrial-derived peptide with strong animal metabolic data and early human trials; SS-31 (elamipretide) spent years in clinical development and won a narrow FDA approval in 2025 for Barth syndrome.
SS-31, clearly: multiple completed trials across mitochondrial myopathy, heart failure, and eye indications, ending in a 2025 FDA approval (Forzinity) for Barth syndrome. MOTS-c has registered human trials underway but no posted controlled human outcome results.
MOTS-c's rodent data, improved insulin sensitivity, exercise capacity, and metabolic homeostasis, map directly onto longevity and body-composition narratives, and it is easy to sell as a research vial. Community schedules (typically 5 to 10 mg per week) are extrapolations from animal work, and MOTS-c is on FDA's 2026 compounding advisory agenda.
It makes SS-31 the rare peptide on this site with an FDA-approved product: for a narrow rare-disease indication, not longevity. It also shows what a real development program looks like: years of trials, and several earlier indications that failed to show efficacy along the way.
| Dimension | MOTS-c | SS-31 / Elamipretide |
|---|---|---|
| Overall evidence grade | D | B |
| Evidence label | Limited human evidence | Moderate human evidence |
| Regulatory status | Investigational / not approved | Approved for specific use |
| Editorial confidence | Low confidence | Moderate confidence |
| Efficacy | 1/5 limited | 3/5 emerging |
| Safety | 1/5 limited | 3/5 emerging |
| Regulatory risk | 4/5 high | 2/5 low |
| Product quality risk | 5/5 very high | 5/5 very high |
| Primary claim categories | Metabolic health claims, Longevity claims, Exercise adaptation claims | Barth syndrome, Mitochondrial disease, Primary mitochondrial myopathy, Age-related macular degeneration, Market-claim quality risk |
MOTS-c remains research-first. Human sources currently show biomarker or association findings, while efficacy, longevity, and use claims still need direct intervention results.
The strongest SS-31 data are for FDA-approved Forzinity in Barth syndrome. Primary mitochondrial myopathy, AMD, cardiovascular, fatigue, performance, and longevity claims need their own direct support.
PubMed. The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance 2015.
PMID:25738459 Accessed 2026-06-08.
Preclinical/metabolic mechanism source.
PubMed. Plasma MOTS-c levels are associated with insulin sensitivity in lean but not in obese individuals 2018.
PMID:29593067 Accessed 2026-06-08.
Human biomarker association source; not an intervention trial.
ClinicalTrials.gov. ClinicalTrials.gov record NCT07505745 2026.
NCT07505745 Accessed 2026-06-08.
Recruiting/no posted-results trial record at the 2026-06-08 source check.
FDA. FDA Grants Accelerated Approval to First Treatment for Barth Syndrome 2025.
Accessed 2026-06-09.
FDA announcement for accelerated approval of Forzinity (elamipretide) injection for Barth syndrome in patients weighing at least 30 kg.
doi:10.1038/s41436-020-01006-8 PMID:33077895 Accessed 2026-06-09.
Peer-reviewed Barth syndrome randomized crossover trial and open-label extension source; the randomized portion did not meet the original primary endpoints.
FDA. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee 2026.
Accessed 2026-07-24.
FDA meeting page for the July 23-24, 2026 PCAC review of BPC-157, KPV, TB-500, MOTs-C, emideltide/DSIP, Semax, and Epitalon bulk substances, including the uses evaluated for each, briefing documents, and docket FDA-2025-N-6895.