# CJC-1295: Research Overview — Biotide Peptides > A literature summary of CJC-1295, the long-acting GHRH analogue: DAC albumin-binding chemistry, sustained GH and IGF-1 pharmacodynamics, serum proteomic shifts and regulatory status. A tetrasubstituted hGRF(1-29) analogue whose Drug Affinity Complex variant covalently binds albumin — documented to sustain GH and IGF-1 elevation for days after a single dose in healthy adults. ## The short version CJC-1295 is a synthetic analogue of growth-hormone-releasing hormone (GHRH) — the signal your hypothalamus sends to tell the pituitary to make and release growth hormone. It is built on the first 29 residues of native GHRH, with four stabilizing amino-acid substitutions that protect it from the enzymes that would otherwise break it down quickly. The **DAC variant** adds a chemical linker that grabs onto serum albumin in the blood — the body's main carrier protein — so the peptide circulates for days rather than minutes. In practice, a single subcutaneous dose of CJC-1295 in healthy adults raised mean plasma GH two- to ten-fold for six or more days and IGF-1 one-and-a-half to three-fold for 9–11 days; with repeated doses, IGF-1 stayed above baseline for up to 28 days [3]. That pharmacodynamic profile — sustained, not fleeting — is what distinguishes it from both plain GHRH and from the short-acting no-DAC form (Modified GRF 1-29). CJC-1295 is not approved for human use anywhere. It is sold strictly as a research chemical and is prohibited in sport under WADA Section S2. This page reports what the studies found — no dose recommendation is given or implied. ## What it is CJC-1295 is a synthetic GHRH analogue built on the first 29 residues of human GRF, hGRF(1-29). Four amino-acid substitutions — D-Ala at position 2, Gln at 8, Ala at 15, Leu at 27 — stabilize the alpha-helix and block dipeptidylpeptidase-IV cleavage, deamidation, and oxidation that would otherwise destroy the native peptide rapidly. In the **DAC (Drug Affinity Complex)** variant, a C-terminal lysine is functionalized with a maleimidopropionyl (MPA) linker that undergoes Michael addition with the free thiol on Cys34 of serum albumin in vivo, forming a covalent peptide-albumin conjugate and extending the plasma half-life toward albumin's own multi-day duration [4]. The **no-DAC form** — also called Modified GRF 1-29 or Mod GRF 1-29 — keeps the four substitutions but lacks the albumin-binding moiety. It has a half-life measured in tens of minutes, not days. The distinction matters enormously: the DAC and no-DAC forms produce very different pharmacodynamic profiles, yet they are routinely conflated in community discussion. A 2025 Nature Reviews Endocrinology review of GHRH and its synthetic analogues provides current framing for the class's receptor signaling and investigational landscape [8]. ## How it works CJC-1295 binds the GHRH receptor (GHRHR), a class-B G-protein-coupled receptor on anterior-pituitary somatotroph cells. GHRHR activation stimulates the Gs/cAMP/PKA signaling cascade, driving both GH synthesis and pulsatile GH release. Released GH then signals the liver to produce IGF-1 (insulin-like growth factor 1), which mediates many of GH's downstream effects on metabolism, body composition, and tissue dynamics. Four things distinguish CJC-1295 from native GHRH in practice: 1. The four stabilizing substitutions prevent rapid enzymatic inactivation in the bloodstream. 2. In the DAC form, covalent albumin binding after subcutaneous injection creates a circulating reservoir that delivers the peptide slowly and continuously to pituitary receptors for days. 3. In rats, the DAC chemistry produced roughly a four-fold increase in GH area under the curve over two hours versus native hGRF(1-29), with albumin-bound peptide detectable beyond 72 hours [4]. 4. Despite the continuous GHRH-axis stimulation from the DAC form, pulsatile GH secretion is preserved: in healthy 20- to 40-year-old men, CJC-1295 raised basal GH approximately 7.5-fold and mean GH by about 46%, with IGF-1 up by about 45% one week later, but the frequency and magnitude of GH pulses were unaltered [11]. ## What the research shows *Class framing.* A 2025 Nature Reviews Endocrinology synthesis of GHRH and its analogues covers the receptor pharmacology rationale, the long-acting analogue design strategy, and the class's therapeutic and investigational landscape — the current authoritative anchor for interpreting individual compound data [8]. *CJC-1295 pharmacodynamics in healthy adults.* A single subcutaneous dose of 30 or 60 micrograms per kilogram raised mean plasma GH two- to ten-fold for 6 or more days and IGF-1 one-and-a-half to three-fold for 9–11 days, with an estimated CJC-1295 half-life of 5.8–8.1 days; after multiple doses, IGF-1 remained above baseline up to 28 days [3]. This is the central human pharmacodynamic dataset. *Albumin-binding mechanism.* In Sprague-Dawley rats, the DAC linker produced a four-fold GH AUC increase over two hours versus plain hGRF(1-29), with detectable albumin-bound peptide beyond 72 hours, establishing the chemistry that produces the DAC form's extended profile [4]. *Pulsatility preserved under continuous stimulation.* In healthy men aged 20–40, CJC-1295 raised trough/basal GH about 7.5-fold and mean GH and IGF-1 by roughly 46% and 45% respectively at one week, while GH pulse frequency and magnitude were statistically unchanged, indicating pulsatility is preserved under continuous GHRH-analogue drive [11]. *Serum proteomic signal.* In eleven healthy young men, CJC-1295 administration shifted the serum proteome detectably: decreased apolipoprotein A1 and a transthyretin isoform; increased a C-terminal albumin fragment and immunoglobulin/beta-hemoglobin species, with the immunoglobulin/albumin-fragment signal correlating linearly with IGF-1, identifying candidate biomarkers of GH/IGF-1 axis activation [10]. *Anti-doping identification.* CJC-1295 was definitively identified by high-resolution LC-MS/MS as the active ingredient in a seized, unlabeled pharmaceutical preparation, confirming its presence in black-market anti-doping contexts and establishing detection methodology [9]. ## Reported effects, cautions & safety CJC-1295 shares the safety profile of the GH-secretagogue class and carries several specific cautions: - *Glucose and insulin sensitivity.* GH is a counter-regulatory hormone that reduces peripheral insulin sensitivity and can raise fasting glucose. The secretagogue class review identifies this as the chief metabolic concern; CJC-1295's multi-day GH and IGF-1 elevation means this signal is sustained, not transient [2]. - *Fluid retention and connective-tissue effects.* GH excess is classically associated with sodium and water retention, soft-tissue swelling, carpal-tunnel-type nerve compression, and arthralgia — GH-mediated effects that are mechanistically expected given the sustained GH elevation CJC-1295 produces [2][3]. - *Theoretical oncologic concern.* IGF-1 is a mitogen; epidemiology links higher circulating IGF-1 with some cancer types. Chronically elevating IGF-1 for days per dose is the context for that concern; causality for secretagogue use is unestablished. - *Compounding-access status.* FDA briefing materials for the 2024 Pharmacy Compounding Advisory Committee cited immunogenicity, peptide-impurity, and cardiac-effect concerns for CJC-1295 as reasons it is not recommended for the 503A compounding bulks list. - *WADA prohibition.* CJC-1295 is prohibited at all times in sport under Section S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics), with established LC-MS/MS detection assays [9]. - *DAC vs. no-DAC confusion.* Community sources routinely conflate the two pharmacokinetically distinct forms. The multi-day data in [3] are from the DAC form; the no-DAC form (Mod GRF 1-29) has a half-life of approximately 30 minutes and produces a very different exposure profile. - *Limited and thin human database.* Published human data are limited to early pharmacokinetic and pharmacodynamic studies; there are no large-scale efficacy or long-term safety trials in healthy adults or in any patient population. ## Where it fits in GH-axis research CJC-1295 is the GHRH-analogue arm of the GH-axis research picture on this desk — the component that drives sustained, days-long GH and IGF-1 elevation. Where [CJC-1295 / Ipamorelin](/cjc1295-ipamorelin) combines it with a GHS-R1a agonist for supra-additive pulsatile release, CJC-1295 alone illustrates what a long-acting GHRH analogue contributes: continuous pituitary priming with preserved pulsatility [11]. The closest approved analogue in its class is tesamorelin, which has generated rigorous RCT evidence in HIV-associated lipodystrophy [1] — the most direct read-across for what GHRH-analogue stimulation of the GH axis can do in humans under controlled conditions. See how CJC-1295 lines up against ipamorelin and the combination on the [comparison page](/compare). ![CJC-1295 GHRH analogue and albumin-binding DAC chemistry research illustration](/images/cjc-1295.webp) --- A peer-reviewed briefing on GH-axis research peptides — citations anchored to primary literature, no products, no clinical recommendations.