Three GHRH Analogs, One Axis

The short version

Peptides For Doctors is a reading desk, not a store. It collects what the published research literature actually says about three peptides that share a single mechanism: they mimic or extend the action of growth hormone-releasing hormone (GHRH), the signal the brain sends to the pituitary gland to release growth hormone. A peptide is a short chain of amino acids — the same building blocks that make up proteins, only smaller. Each of these three triggers the pituitary's own GH secretion rather than supplying exogenous hormone, which means the body's normal feedback controls stay intact.

This desk has one job: tell you, in plain language and with citations, what each peptide was tested on, in which populations, and how far the evidence actually reaches. Sermorelin has the longest clinical record, including former FDA approval. Tesamorelin is the only one with current FDA approval, though for a narrow indication. CJC-1295 has never been approved and has only early pharmacokinetic human data. None of these is a medicine you can prescribe without appropriate context. This desk does not sell anything, does not give medical advice, and never lists a human dose.

What are research peptides?

Hormones, enzymes, and signaling molecules in the body are often proteins — long chains of amino acids folded into a specific shape. A peptide is a much shorter chain of the same amino acids, sometimes only a few links long. Because they are small and specific, peptides can act like keys that fit particular receptor locks on cells, activating or modulating particular biological processes.

A research peptide is one that has been synthesized and studied in the laboratory — in cell cultures, in animals, and occasionally in human trials — but may or may not hold regulatory approval for a given use. The label matters: where approval exists, it is for a specific indication and patient population; uses outside that indication are off-label. Where no approval exists, dosing, long-term safety, and effectiveness in people are largely unestablished. When this site reports a number from a study, it reports it exactly as the study did — never as a recommendation.

How these three fit into growth hormone research

The three peptides on this desk are all GHRH analogs — synthetic molecules built on the same template as the brain's own growth-hormone-releasing signal — but they were engineered for different durations and regulatory contexts.

• Sermorelin is the lead. A 29-amino-acid fragment of endogenous GHRH, it is the shortest piece that retains full receptor activity. It was formerly approved as Geref for pediatric GH deficiency and withdrawn for commercial (not safety) reasons in 2008; it now lives in 503A compounding. Human trial data go back to 1992 ^[7].
• Tesamorelin is the full 44-amino-acid GHRH sequence with an N-terminal modification that blocks enzymatic cleavage, extending plasma stability. It is FDA-approved to reduce visceral fat in HIV-positive adults with lipodystrophy, and carries the strongest RCT evidence of the three ^[8][10].
• CJC-1295 is a further-engineered analog: four protease-blocking substitutions plus (in the DAC variant) a reactive linker that covalently attaches to albumin, pushing half-life to 5-8 days ^[15]. It has never been approved, and its human data are limited to pharmacokinetic studies in healthy adults ^[15][16].

Together they trace the evolution of a single therapeutic idea — stimulating the body's own GH axis — from short-acting clinical compound to long-acting research tool. Use the directory to read each one, or compare these peptides side by side.

A note on how this desk reads the literature

Peptides For Doctors is a cross-referenced literature digest. Each peptide page summarizes the peer-reviewed studies for that compound, cites them by number, and links to a single shared references list that aggregates every source across all three. Where the evidence is limited, off-label, or preclinical, we say so plainly — that is part of the record. We describe research findings and the cited cautions that come with them; we do not recommend, prescribe, or sell. The aim is an accurate, efficient map of what is known, so readers can see where the science is solid, where it is investigational, and where it remains mostly theoretical.