CJC-1295

Molecular identity

Sequence

Tyr-D-Ala-Asp-Ala-Ile-Phe-Thr-Gln-Ser-Tyr-Arg-Lys-Val-Leu-Ala-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Leu-Ser-Arg-Lys-NH2 · Lys30 ε-amine acylated with 3-maleimidopropionic acid (the Drug Affinity Complex)

Formula

C165H269N47O46

Molecular weight

3647.2 g/mol

CAS

863288-72-6

PubChem CID

91971820

What it acts on

• GHRH receptor on pituitary somatotrophs — the molecule is built on the GHRH(1-29) pharmacophore, and the cited literature describes it as a long-acting GHRH analogue that stimulates growth-hormone production from the pituitary gland.
• Serum albumin and other circulating plasma proteins — the C-terminal maleimido group binds them covalently, and the resulting conjugates are reported to have a far longer half-life than the unconjugated peptide.
• The growth-hormone → hepatic IGF-1 axis — in the cited human trial, IGF-1 rose 1.5- to 3-fold and stayed elevated for days after the growth-hormone response itself, with accumulation on repeated administration.
• IGF-1 signalling and satellite-cell repair — what one of the two cited orthopaedic reviews attributes to growth-hormone secretagogues as a class, on preclinical grounds rather than trial data. The PI3K/Akt, mTOR, MAPK, TGF-β and AMPK pathways that same review names belong to a broader mechanistic map it draws for therapeutic peptides in general, not to this class specifically; the other review makes no pathway claim for this compound at all.

What the studies report

Each item below summarises the paper it is numbered to, written from that paper's own abstract. The badge says how the evidence was produced.

1. 1.
   human studyJ Clin Endocrinol Metab (2006)

   Two randomised, double-blind, placebo-controlled ascending-dose trials in healthy adults aged 21 to 61, conducted across two investigational sites; one trial gave each subject a single administration, the other repeated administration. The endpoints were pharmacokinetic and hormonal, not clinical — plasma growth hormone rose dose-dependently by roughly 2- to 10-fold and stayed elevated for six days or more, IGF-1 by 1.5- to 3-fold for nine to eleven days, and the estimated half-life was on the order of a week. After repeated administration IGF-1 remained above baseline for up to about four weeks, which the authors read as a cumulative effect. No serious adverse reactions were reported, and the conclusion is framed as supporting potential utility rather than demonstrating benefit.

2. 2.
   reviewJ Am Acad Orthop Surg Glob Res Rev (2026)

   A 2026 review of therapeutic peptides in orthopaedics. It groups CJC-1295 with the other growth-hormone secretagogues discussed there — ipamorelin, tesamorelin, sermorelin, AOD-9604 — as agents said to activate IGF-1 signalling and satellite-cell repair, inside a broader mechanistic map covering PI3K/Akt, mTOR, MAPK, TGF-β and AMPK pathways. The review states plainly that although the preclinical work is promising, clinical trials are currently lacking.

3. 3.
   reviewAm J Sports Med (2026)

   A narrative review written for orthopaedic and sports-medicine physicians, based on a PubMed search of biochemical and clinical studies of the most popular injectable peptides. The only evidence it reports for CJC-1295, and only in combination with ipamorelin, is murine: significantly improved maximum tetanic tension in mouse models of glucocorticoid-induced muscle loss, which the authors state is confined to animal studies. Their overall conclusion is that indications and treatment parameters remain unknown and that substantial safety and efficacy research is needed before any recommendation can be made.

4. 4.
   in vitroDrug Test Anal (2019)

   An anti-doping analytical study rather than a biology study: a confirmation method for CJC-1295 in equine plasma by LC-MS/MS after immunoaffinity capture and tryptic digestion, complementing an earlier immuno-PCR screen, with identification down to about 180 pg/mL. It matters here for two things. It describes the molecule itself — a C-terminal maleimido group that covalently binds plasma proteins such as serum albumin, conjugates with a much greater half-life than the free peptide, and stimulation of growth-hormone production reported for more than six days in humans after a single administration. And it documents a real difficulty: the conjugated form is hard to detect because it is low in abundance, high in molecular weight and distributed across a range of different protein substrates.

Used in research on