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Peptide Evidence Registry

Comparison Centre

Two compounds, the same questions, no cherry-picking

Marketing compares compounds on whichever measure flatters them. This compares them on the same fields every time — including the awkward ones like how much human safety data exists. Every score here rates the evidence, not the compound: a higher number means stronger or more mature research, not that something is safer or works better.

Sharing keeps the two compounds you picked.

How to read these scores

Every number here rates the evidence, not the compound. They are editorial 0-100 strength ratings, not percentages, and not a rating out of five stars.

  • Human efficacy evidence strength — Higher = more and better-quality human evidence. It does not mean the effect is bigger or that the compound works for you.
  • Preclinical evidence strength — Higher = more animal, tissue or cell research. Preclinical results are a starting point, not proof of a human benefit.
  • Human safety evidence strength — Higher = more mature, better-documented human safety data. It does not mean the compound is safer than one with a lower number. A score of 80 does not mean “80% safe”.
  • Evidence level (L0-L5) — the strongest type of study behind the compound, from anecdote (L0) to large replicated human trials (L5). It is a description of the study evidence, not a quality, safety or recommendation rating.
  • Confidence — how likely we think it is that this rating changes as new research lands. Low confidence means the picture is unsettled, not that the compound is bad.

None of these ratings is medical advice, a safety guarantee, or a recommendation to use anything. How we grade evidence.

SS-31 / Elamipretide

A mitochondria-targeting peptide with a narrow accelerated approval and a much broader set of unproven anti-ageing claims.

L3Early human studiesApproved for a specific indication · FDA (US)
Full profile

MOTS-c

A mitochondrial-derived peptide with genuinely interesting biology and thin translational data.

L2Animal / lab studiesResearch / unapproved supply
Full profile

How far human research has progressed

SS-31 / Elamipretide

Approved for one rare disease; investigational or unestablished elsewhere

MOTS-c

Preclinical with early translational human observation

Claim-specific benefit evidence

A human exposure study or trial registration does not establish that the claimed benefit occurs.

SS-31 / Elamipretide

Not separately assessed; see the full profile.

MOTS-c

Not separately assessed; see the full profile.

Human research context

SS-31 / Elamipretide

Approved for one rare disease; investigational or unestablished elsewhere

MOTS-c

Preclinical with early translational human observation

Human efficacy evidence strength

Higher = more and better-quality human evidence. It does not mean the effect is bigger or that the compound works for you.

SS-31 / Elamipretide

Strength of the human efficacy evidence42 of 100 evidence strength

MOTS-c

Strength of the human efficacy evidence20 of 100 evidence strength

Preclinical (animal / lab) evidence strength

Higher = more animal, tissue or cell research. Preclinical results are a starting point, not proof of a human benefit.

SS-31 / Elamipretide

Strength of the animal and lab evidence80 of 100 evidence strength

MOTS-c

Strength of the animal and lab evidence70 of 100 evidence strength

Human safety evidence strength

Higher = more mature, better-documented human safety data. It does not mean the compound is safer than one with a lower number.

SS-31 / Elamipretide

Strength of the human safety evidence55 of 100 evidence strength

MOTS-c

Strength of the human safety evidence12 of 100 evidence strength

Regulatory status (legal position, not proof it works)

SS-31 / Elamipretide

Named regulators: FDA (US)

On 19 September 2025 the FDA granted accelerated approval to Forzinity (elamipretide) injection to improve muscle strength in patients with Barth syndrome weighing at least 30 kg — based on a surrogate endpoint, with a confirmatory trial still required. That approval says nothing about general anti-ageing, athletic or longevity use, where it remains unapproved and unestablished. On 24 August 2026 the FDA issued warning letters to Royal Peptides LLC, Peptide Partners LLC and TXP Innovations LLC (Tex Peptides) identifying vendor products labelled 'SS-31 (Elamipretide)' as unapproved new drugs; those products are not the approved Forzinity medicine, and FDA noted that injectable products sold this way are especially concerning because injection bypasses key body defences.

MOTS-c

Check jurisdiction-specific details in the profile.

Not an approved medicine. Research compound; also prohibited in sport. FDA's Pharmacy Compounding Advisory Committee considered MOTS-c in July 2026 for possible inclusion on the 503A Bulks List. Its recommendations are non-binding: this is a compounding-policy process, not FDA drug approval, validation of efficacy claims or blanket legalisation.

Common claims

SS-31 / Elamipretide

  • · Restores youthful mitochondrial function
  • · Improves endurance and recovery
  • · Slows ageing
  • · Improves heart and kidney outcomes

MOTS-c

  • · Reverses age-related metabolic decline
  • · Improves insulin sensitivity and exercise capacity
  • · Extends healthspan

How settled our evidence rating is

SS-31 / Elamipretide

Low confidence in ratingL3Early human studies

MOTS-c

Very low confidence in ratingL2Animal / lab studies

Cancer-related questions raised by the biology

These are theoretical or monitored questions raised by how a compound works. They are not evidence that it causes cancer.

SS-31 / Elamipretide

No established human cancer signal. Improving mitochondrial efficiency has theoretical bidirectional implications in tumour metabolism, but nothing demonstrated clinically.

MOTS-c

AMPK signalling has context-dependent roles in cancer biology — sometimes tumour-suppressive, sometimes supportive of stress survival. This is a mechanistic unknown, not a demonstrated risk or benefit in humans.

What this adds up to, in plain English

SS-31 / Elamipretide

Preliminary human observations exist, but they may not establish a treatment-attributable benefit.

MOTS-c

The interesting work is in animals and lab studies. Treating it as an established human treatment is not supported by evidence.

A comparison is not a recommendation

Neither column here is an endorsement, and the compound with the higher numbers is not the “better” or “safer” one — it is simply the one with more or better-quality research behind it. Two compounds can both be poorly evidenced, and better-evidenced says nothing about whether either is a sensible idea for a specific person. That is a conversation for a qualified clinician.