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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.

HDAP2

A short mitochondria-targeted research peptide that binds cardiolipin. Evidence is cell and mouse work, including 2026 optic-nerve injury data.

L2Animal / lab studiesResearch / unapproved supply
Full profile

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

How far human research has progressed

HDAP2

Preclinical — cell studies and mouse retinal and optic-nerve models

SS-31 / Elamipretide

Approved for one rare disease; investigational or unestablished elsewhere

Claim-specific benefit evidence

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

HDAP2

Not separately assessed; see the full profile.

SS-31 / Elamipretide

Not separately assessed; see the full profile.

Human research context

HDAP2

Preclinical — cell studies and mouse retinal and optic-nerve models

SS-31 / Elamipretide

Approved for one rare disease; investigational or unestablished elsewhere

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.

HDAP2

Strength of the human efficacy evidence0 of 100 evidence strength

SS-31 / Elamipretide

Strength of the human efficacy evidence42 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.

HDAP2

Strength of the animal and lab evidence35 of 100 evidence strength

SS-31 / Elamipretide

Strength of the animal and lab evidence80 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.

HDAP2

Strength of the human safety evidence3 of 100 evidence strength

SS-31 / Elamipretide

Strength of the human safety evidence55 of 100 evidence strength

Regulatory status (legal position, not proof it works)

HDAP2

Check jurisdiction-specific details in the profile.

Not an approved medicine and not in human trials in our curated record. It is an academic research peptide supported by published work and NIH-funded projects.

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.

Common claims

HDAP2

  • · Neuroprotection and vision preservation
  • · Mitochondrial membrane repair
  • · Protection against nerve injury

SS-31 / Elamipretide

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

How settled our evidence rating is

HDAP2

Very low confidence in ratingL2Animal / lab studies

SS-31 / Elamipretide

Low confidence in ratingL3Early human 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.

HDAP2

Not established. No human data exist in either direction.

SS-31 / Elamipretide

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

What this adds up to, in plain English

HDAP2

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

SS-31 / Elamipretide

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

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.