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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.

Histrelin

A GnRH-agonist implant approved for central precocious puberty, releasing peptide continuously for about a year per implant.

L4Good human trialsApproved for a specific indication · FDA (US)
Full profile

Leuprolide

A GnRH agonist whose depot injections switch off sex-hormone production — used in prostate cancer, endometriosis and central precocious puberty depending on the product.

L5Repeated human trialsApproved medicine (jurisdiction-specific) · FDA (US)
Full profile

How far human research has progressed

Histrelin

Approved narrow paediatric indication

Leuprolide

Established hormone-suppression medicine family

Claim-specific benefit evidence

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

Histrelin

Not separately assessed; see the full profile.

Leuprolide

Not separately assessed; see the full profile.

Human research context

Histrelin

Approved narrow paediatric indication

Leuprolide

Established hormone-suppression medicine family

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.

Histrelin

Strength of the human efficacy evidence68 of 100 evidence strength

Leuprolide

Strength of the human efficacy evidence85 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.

Histrelin

Strength of the animal and lab evidence60 of 100 evidence strength

Leuprolide

Strength of the animal and lab evidence75 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.

Histrelin

Strength of the human safety evidence65 of 100 evidence strength

Leuprolide

Strength of the human safety evidence80 of 100 evidence strength

Regulatory status (legal position, not proof it works)

Histrelin

Named regulators: FDA (US)

FDA-approved (Supprelin LA) as a subcutaneous implant for treatment of children with central precocious puberty. Approval is specific to that paediatric indication and product.

Leuprolide

Named regulators: FDA (US)

Multiple FDA-approved depot products exist with different indications — advanced prostate cancer, endometriosis, preoperative management of uterine fibroids and central precocious puberty among them. Each formulation and dosing interval is approved for specific uses.

Common claims

Histrelin

  • · Halts progression of central precocious puberty while implanted

Leuprolide

  • · Suppresses testosterone in advanced prostate cancer
  • · Suppresses oestrogen in endometriosis
  • · Pauses central precocious puberty

How settled our evidence rating is

Histrelin

Moderate confidence in ratingL4Good human trials

Leuprolide

High confidence in ratingL5Repeated human trials

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.

Histrelin

No established human cancer signal within approved use.

Leuprolide

Used deliberately as a treatment in hormone-sensitive prostate cancer; no cancer-promotion signal within approved use.

What this adds up to, in plain English

Histrelin

Real controlled human trials exist, but questions about approval, how long benefits last, or long-term safety are still open.

Leuprolide

Repeated large human trials support specific uses in the groups studied. That is strong evidence something works there — not proof it suits everyone or is free of risk.

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.