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CJC-1295

Growth Hormone

Also known as: CJC-1295 DAC, CJC-1295 no DAC, Modified GRF 1-29, Mod GRF, Tesamorelin analog

Half-life: ~30 minutes (no DAC) / 6-8 days (with DAC)

Muscle GrowthAnti AgingFat Loss

Overview

CJC-1295 is a synthetic analog of growth hormone releasing hormone (GHRH) that stimulates the pituitary gland to produce and secrete growth hormone. It consists of the first 29 amino acids of GHRH with four amino acid substitutions at positions 2, 8, 15, and 27 to improve metabolic stability and resistance to enzymatic degradation. The peptide exists in two primary forms: with and without a Drug Affinity Complex (DAC), which dramatically affects its pharmacokinetic profile.

The DAC version features a maleimidopropionic acid linker that enables covalent binding to serum albumin in vivo, extending the half-life from roughly 30 minutes to 6-8 days. This creates a sustained elevation of GH and IGF-1 levels over several days following a single injection. The no-DAC version, commonly referred to as Modified GRF 1-29 or Mod GRF, has a much shorter half-life and produces a more acute, pulsatile GH release pattern that more closely mimics the body's natural GH secretion rhythm.

CJC-1295 is frequently combined with the growth hormone secretagogue Ipamorelin, as the two peptides work through complementary mechanisms. CJC-1295 amplifies the GHRH signal while Ipamorelin triggers GH release through the ghrelin receptor, producing a synergistic effect that results in greater GH output than either peptide alone. This combination has become one of the most popular protocols in the peptide community for anti-aging, body composition, and recovery purposes.

History

CJC-1295 was developed by ConjuChem Biotechnologies (now Conjuchem LLC) of Montreal, Canada in the early 2000s. It was designed as a modified version of the first 29 amino acids of growth hormone releasing hormone (GHRH 1-29, also known as sermorelin) with amino acid substitutions at positions 2, 8, 15, and 27 to improve metabolic stability. The DAC (Drug Affinity Complex) version features a maleimidopropionic acid linker that enables covalent binding to serum albumin, dramatically extending the half-life. Clinical trials by Teichman et al. (2006) demonstrated sustained GH and IGF-1 elevation. The "no DAC" version (Mod GRF 1-29) became more popular in the peptide community due to more physiological, pulsatile GH release patterns.

Effects

  • Increases growth hormone secretion from the pituitary
  • Elevates IGF-1 levels for sustained anabolic signaling
  • Promotes fat metabolism and improved body composition
  • Supports deeper, more restorative sleep patterns
  • Enhances recovery from exercise and tissue repair

Side Effects

  • Injection site redness, swelling, or irritation
  • Water retention and bloating
  • Tingling or numbness in the extremities
  • Headache
  • Dizziness or flushing shortly after injection

Tolerability

CJC-1295 is moderately well tolerated. The most common side effects include injection site irritation, water retention, and tingling in the extremities. The DAC version may produce more pronounced side effects due to its sustained activity over several days, creating a continuous rather than pulsatile GH elevation. The no-DAC version (Mod GRF) is generally better tolerated as it allows the body to maintain more natural GH secretion patterns. Side effects typically diminish after the first few weeks of use.

Dosing Ranges

Anti-aging and recovery (Mod GRF)

Dose Range

100 mcg

Frequency

Once to three times daily (SubQ)

Duration

8-12 weeks

Body composition (Mod GRF + Ipamorelin)

Dose Range

100-300 mcg

Frequency

Two to three times daily

Duration

8-12 weeks

CJC-1295 with DAC

Dose Range

1000-2000 mcg

Frequency

Once or twice weekly

Duration

8-12 weeks

Dosing information is for educational purposes only. Consult a healthcare professional before using any peptide.

Reconstitution

Preparation Details

Typical Vial Size

2 mg

Water Type

Bacteriostatic water (BAC water)

Mixing Volume

2 mL

Half-Life

~30 minutes (no DAC) / 6-8 days (with DAC)

Molecular Weight

3367.9 Da (Mod GRF 1-29)

Store reconstituted vial refrigerated at 2-8°C. Use within 28 days. The DAC version is more stable in solution than the no-DAC version.

Regulatory Status

FDA Status

Not FDA approved for human use.

Legal Status

Unregulated research chemical. Prohibited by WADA.

USA

Not approved

Not approved for human use

EU

Not approved

Not authorized as medicinal product

UK

Not approved

Not approved — research chemical

Australia

Not approved

TGA has not evaluated

Russia

Not approved

Available as research compound

Canada

Not approved

Not approved — despite being developed by Canadian company ConjuChem

Cited Studies

Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults

Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Bhner LA

Journal of Clinical Endocrinology & Metabolism (2006)

Demonstrated that CJC-1295 produces sustained increases in GH and IGF-1 levels with multiple dose-dependent peaks over 6-14 days following a single subcutaneous injection.

View Study →

Stimulation of the growth hormone (GH)-insulin-like growth factor I axis by daily and intermittent administration of a GH-releasing factor analog (CJC-1295)

Ionescu M, Frohman LA

Journal of Clinical Endocrinology & Metabolism (2006)

Showed that both daily and weekly CJC-1295 administration effectively stimulated the GH-IGF-1 axis, with weekly dosing producing more sustained IGF-1 elevation.

View Study →

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