Peptide Profiles

Evidence-led profiles covering mechanisms, research stages, limitations and unresolved questions for individual peptides and related research compounds.

Retatrutide: Mechanism, Clinical Research and Current Evidence

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. Retatrutide (LY3437943) is an investigational peptide designed to activate GIP, GLP-1 and glucagon receptors. It has progressed into Phase 3 research, but it is […]

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BPC-157: What the Preclinical Evidence Does—and Does Not—Show

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. BPC-157 is a synthetic 15-amino-acid peptide studied mainly in cells and animal models. Public interest is far ahead of robust human clinical evidence. Key

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TB-500 and Thymosin Beta-4: Understanding the Research Distinction

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. TB-500 is a name used for a synthetic peptide associated with thymosin beta-4 research. The two terms should not be treated as interchangeable without

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GHK-Cu: Copper Binding, Cell Signalling and the Strength of the Evidence

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. GHK-Cu is the copper(II) complex of the naturally occurring tripeptide glycyl-L-histidyl-L-lysine. Laboratory evidence is extensive, while formulation-specific human evidence is more limited. Key points

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MOTS-c: A Mitochondrial-Derived Peptide in Metabolic Research

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. MOTS-c is a 16-amino-acid peptide encoded within mitochondrial 12S rRNA. Research explores metabolic stress signalling, but most intervention evidence remains preclinical. Key points The

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Semax: ACTH-Derived Peptide Research and Evidence Gaps

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. Semax is a synthetic ACTH(4–7)-derived heptapeptide extended with Pro-Gly-Pro. Much of its published literature comes from Russian preclinical and regional clinical research. Key points

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Selank: Tuftsin-Derived Peptide Research and Human Evidence

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. Selank is a synthetic heptapeptide derived from the naturally occurring immunomodulatory peptide tuftsin. Published research examines stress, behaviour and gene expression, but high-quality human

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PT-141 and Bremelanotide: From Melanocortin Research to Clinical Trials

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. PT-141 is an early research designation for bremelanotide, a cyclic melanocortin receptor agonist. A specific pharmaceutical formulation is FDA-approved in the United States, but

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Melanotan II: Melanocortin Biology, Early Human Studies and Safety Questions

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. Melanotan II is a synthetic cyclic analogue of alpha-melanocyte-stimulating hormone. Human research is old and small, while unregulated use has generated important safety concerns.

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CJC-1295 No DAC and Ipamorelin: Two Growth-Hormone Signalling Pathways

Evidence reviewed: 22 July 2026 · Author: ExtolX Editorial Team · Scientific review: Pending Educational information for laboratory research audiences. This article does not provide medical advice, dosage or administration guidance. CJC-1295-type peptides and ipamorelin act through different upstream receptors in growth-hormone research. Evidence for each compound should be separated from evidence for their combination.

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