CJC-1295 without DAC (Mod GRF 1-29) — Growth Hormone
Short-acting GHRH analog for pulsatile GH release. Research peptide commonly paired with GH-releasing peptides.
Overview
CJC-1295 without DAC, more accurately called Modified GRF (1-29) or Mod GRF 1-29, is a synthetic analog of the first 29 amino acids of growth hormone-releasing hormone (GHRH) with amino acid substitutions at positions 2 (D-Ala), 8 (Gln), 15 (Ala), and 27 (Leu). These modifications provide resistance to enzymatic degradation by dipeptidyl peptidase-IV (DPP-IV) without the albumin-binding DAC component. Without DAC, Mod GRF 1-29 has a half-life of approximately 30 minutes, producing a short, pulsatile GH release that more closely mimics the physiologic pattern of natural GHRH secretion compared to the sustained release of CJC-1295 with DAC. Mod GRF 1-29 is typically administered 2-3 times daily, often at bedtime and upon waking, to enhance natural GH pulses. It is almost always combined with a growth hormone-releasing peptide (GHRP) such as ipamorelin or GHRP-2, as the combination of GHRH + GHRP produces synergistic GH release approximately 3-5 times greater than either component alone. This synergy occurs because GHRH and GHRPs act through different receptors — GHRH through the GHRH receptor and GHRPs through the growth hormone secretagogue receptor (GHSR/ghrelin receptor). Mod GRF 1-29 has no FDA-approved indications and is available only as a research peptide.
Indications
- No approved indications
- Unapproved: Pulsatile GH optimization (anti-aging)
- Unapproved: Body composition improvement
- Unapproved: Sleep quality enhancement (via GH pulse augmentation)
Mechanism of Action
Binds and activates GHRH receptors on pituitary somatotrophs, initiating cAMP-mediated GH gene transcription and secretion
Dosing
| Compound | Dose | Frequency | Notes |
|---|---|---|---|
| Mod GRF 1-29 | 100 mcg | 2-3 times daily (pre-bed, morning, post-workout) | Common dose; usually combined with GHRP |
| Mod GRF 1-29 + Ipamorelin | 100 mcg + 100 mcg | 2-3 times daily | Synergistic combination — most popular stack |
Evidence Grade
GRADE C
Safety & Contraindications
- Not FDA-approved — research peptide only
- Injection site reactions (flushing, warmth) common immediately post-injection
- May cause hunger increase (especially when combined with GHRP-6)
- Transient facial flushing and head rush within minutes of injection
- Quality varies between peptide suppliers
- Limited human safety data