CJC-1295 + Ipamorelin Stack: Research Guide to a GHRH + GHRP Combination

For informational purposes only. This article describes the preclinical research literature on CJC-1295 (No DAC) and Ipamorelin as paired research compounds in growth-hormone-axis studies. All research described is from rodent and in vitro models. Nothing below constitutes medical, clinical, or dosing guidance. Both compounds are sold by MOG Research strictly for laboratory research — not for human or animal administration.

TL;DR

CJC-1295 (No DAC) is a modified GHRH(1-29) analogue that activates the growth hormone-releasing hormone receptor (GHRHR) with extended half-life vs. native GHRH due to DPP-4 resistance.
Ipamorelin is a selective pentapeptide agonist of the growth hormone secretagogue receptor (GHSR1a) — a distinct receptor from GHRHR — and is notable for its selectivity (minimal cortisol, prolactin, ACTH effects in rodent studies).
Combining a GHRH analogue (CJC-1295) with a GHRP / ghrelin-mimetic (Ipamorelin) is the most-studied paradigm in preclinical growth-hormone-pulse research. The combination produces a larger pulsatile GH response in rodent models than either compound alone — a finding interpreted as GHRH/GHRP synergy rather than additive signaling.
The 1:1 mass ratio (5mg + 5mg) is the most-cited combination protocol in published research.

Two Pathways to a Single GH Pulse

Anterior pituitary somatotrophs — the cells that produce and release growth hormone (GH) — have two principal physiological release triggers:

GHRH-mediated release through the GHRHR (growth hormone-releasing hormone receptor), a Gs-protein-coupled receptor that activates adenylyl cyclase and elevates intracellular cAMP, triggering GH exocytosis.
Ghrelin-mimetic release through the GHSR1a (growth hormone secretagogue receptor 1a), a Gq-protein-coupled receptor that activates phospholipase C and elevates intracellular calcium, triggering GH exocytosis through a partially independent pathway.

These two pathways converge on the same cellular outcome — GH release — but operate through distinct intracellular signaling cascades. Co-activation of both receptors in rodent studies has consistently produced a GH pulse magnitude greater than the sum of the individual pulses produced by either pathway alone (Bowers et al., 1991; Hartman et al., 1992). This phenomenon — described in the literature as GHRH/GHRP synergy — is the mechanistic basis for combination research protocols.

CJC-1295 and Ipamorelin are research tools that allow this synergy to be examined with two practical advantages over earlier-generation GHRH/GHRP compounds:

CJC-1295’s DPP-4 resistance extends functional half-life vs. native GHRH(1-29)
Ipamorelin’s receptor selectivity at GHSR1a (without significant cortisol, prolactin, ACTH, or gonadotropin effects in rodent studies) provides a cleaner pharmacological tool than earlier GHRPs like GHRP-2 or GHRP-6

CJC-1295 (No DAC): Mechanism in Detail

CJC-1295 is a synthetic peptide modification of native GHRH(1-29). The full GHRH peptide is 44 amino acids long, but the first 29 amino acids contain the full receptor-activating domain — making GHRH(1-29) (also called sermorelin in its unmodified form) a functional minimal-sequence GHRH agonist.

CJC-1295 modifies GHRH(1-29) with four amino acid substitutions:

D-Ala² — replaces L-Ala at position 2; protects against DPP-4 cleavage
Gln⁸ — replaces Glu at position 8; improves stability
Ala¹⁵ — replaces Gly at position 15; improves activity
Leu²⁷ — replaces Met at position 27; protects against oxidation

These substitutions extend the peptide’s half-life by an order of magnitude compared to native GHRH(1-29). The result is a research compound that produces a measurable, sustained GH-releasing signal at GHRHR over a window practical for rodent dosing protocols.

The “No DAC” vs “DAC” Distinction

A separate, optional modification — the Drug Affinity Complex (DAC) — is a maleimidopropionic acid lysine derivative conjugated to the C-terminus that allows CJC-1295 to bind covalently to serum albumin. The DAC version of CJC-1295 has a half-life of approximately 6–8 days in rodent models due to this albumin binding.

CJC-1295 No DAC lacks the DAC moiety and has a half-life on the order of 30 minutes. This shorter half-life makes the No DAC version preferred in research protocols that aim to preserve the natural pulsatile pattern of GH release. The DAC version produces continuously elevated GH levels — which is useful for some research questions but eliminates the pulsatility that is one of the most physiologically important characteristics of natural GH secretion.

MOG Research’s CJC-1295 + Ipamorelin Blend uses the No DAC formulation for this reason.

Ipamorelin: Mechanism in Detail

Ipamorelin is a synthetic pentapeptide with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH₂. It is a selective agonist of the growth hormone secretagogue receptor (GHSR1a), the same receptor activated by endogenous ghrelin.

The distinguishing feature of Ipamorelin in the GHRP class is its selectivity profile. Raun et al. (1998), publishing in the European Journal of Endocrinology, reported that at GH-effective doses in rodent and porcine models, Ipamorelin produced minimal effects on:

Cortisol release (in contrast to GHRP-6 and GHRP-2, which raise cortisol substantially at GH-effective doses)
Prolactin release
ACTH release
FSH and LH release

This selectivity makes Ipamorelin the cleanest GHSR1a agonist for research where dissecting GH-axis signaling from broader pituitary effects is important (PMID: 9849832).

Why Combine the Two Compounds

The published rationale for combining a GHRH analogue with a GHRP / ghrelin-mimetic is:

Pathway independence. GHRHR (Gs/cAMP) and GHSR1a (Gq/Ca²⁺) operate through distinct intracellular signaling cascades. Activation of both receptors simultaneously produces additive — and in published studies often synergistic — GH release.

Somatostatin inhibition reduction. Endogenous somatostatin tonically inhibits GH release. GHRPs (including Ipamorelin) have been reported to reduce somatostatin-mediated inhibition at the somatotroph level, amplifying the GHRH-driven signal.

Pulse pattern preservation. Using short-half-life forms of both compounds (CJC-1295 No DAC, Ipamorelin) preserves the pulsatile character of natural GH release, in contrast to long-acting analogues that produce continuously elevated GH levels.

The combination has become the most-cited paired peptide stack in growth-hormone-axis preclinical research as a result.

The 1:1 Mass Ratio: Why It’s the Standard

The 1:1 mass ratio (e.g., 5mg CJC-1295 No DAC + 5mg Ipamorelin per vial) is the most-cited combination ratio in published research. The rationale:

Comparable potency at receptor-effective concentrations
Simplified protocol design — researchers can dose by total mass without separate per-compound calculations
Historical precedent from the GHRP-2 / sermorelin combination literature that informed early CJC-1295 / Ipamorelin protocol design

Researchers using ratios other than 1:1 should justify the choice from their specific research question rather than assuming the 1:1 ratio is universally optimal — the published data on alternative ratios is limited.

Comparison to Other GH-Axis Research Tools

Research Tool	Mechanism	Best For
CJC-1295 No DAC	GHRH analogue, ~30 min half-life	Pulsatile GHRH-pathway research
CJC-1295 + DAC	GHRH analogue, 6–8 day half-life	Continuously elevated GH research
Ipamorelin	Selective GHSR1a agonist	Clean GHRP-pathway research (no cortisol axis interference)
GHRP-2 / GHRP-6	Non-selective GHSR1a agonists	Earlier-generation GHRP research; raises cortisol
Tesamorelin	Stabilized full-length GHRH(1-44)	GHRHR research using highest-fidelity GHRH analogue
Sermorelin	Native GHRH(1-29)	Short-acting GHRH research (limited DPP-4 resistance)

For Tesamorelin specifically, see our Tesamorelin product page for research-grade material.

Practical Considerations for Combination Research

Reconstitution: Both compounds dissolve readily in bacteriostatic water at typical research concentrations. A pre-blended vial (as supplied by MOG Research) eliminates the need to reconstitute and combine two separate vials, reducing handling error.
Storage: Lyophilized at -20°C, stable 24–36 months. Reconstituted at 2–8°C, used within 28–30 days.
Pulsatility: Protocols designed to preserve pulsatile GH release typically use intermittent rather than continuous administration to mirror the natural pattern of GHRH secretion.
Endogenous somatostatin: Background somatostatin tone varies with time of day in rodent models. Researchers should standardize the administration time within their protocols for reproducibility.

Frequently Asked Questions

What is the CJC-1295 + Ipamorelin stack used for in research?

In preclinical literature, the combination is used to study pulsatile growth hormone release through concurrent activation of two distinct pituitary signaling pathways (GHRHR via CJC-1295, GHSR1a via Ipamorelin). The combination produces a larger GH pulse than either compound alone in rodent models — a phenomenon called GHRH/GHRP synergy.

What is the difference between CJC-1295 with DAC and without DAC?

CJC-1295 with DAC has a Drug Affinity Complex conjugated to the peptide that allows it to bind serum albumin, extending half-life to 6–8 days in rodent studies. CJC-1295 No DAC lacks this conjugation; its half-life is ~30 minutes. The No DAC version is preferred for research preserving pulsatile GH release.

Why is Ipamorelin paired with CJC-1295 instead of other GHRPs?

Ipamorelin’s selectivity at GHSR1a — with minimal cortisol, prolactin, ACTH, or gonadotropin effects in rodent studies — makes it the cleanest GHSR1a agonist for research where isolating GH-axis signaling from broader pituitary effects matters. Earlier GHRPs (GHRP-2, GHRP-6) raise cortisol substantially at GH-effective doses.

What is the recommended ratio of CJC-1295 to Ipamorelin in research?

The 1:1 mass ratio is the most-cited combination ratio in published preclinical literature (e.g., 5mg + 5mg per vial). Researchers using alternative ratios should base the choice on their specific research design; the published data on non-1:1 ratios is limited.

Is this combination legal to purchase for research in the US?

Both CJC-1295 and Ipamorelin are sold by MOG Research strictly for laboratory research use only. Neither is an FDA-approved drug and neither is legal for human or animal consumption or administration.

Citations

Bowers CY et al. (1991). On the actions of the growth hormone-releasing hexapeptide, GHRP. (Foundational GHRP synergy literature)
Hartman ML et al. (1992). Growth hormone-releasing hormone and GHRP combination effects. (Foundational GHRH/GHRP combination literature)
Raun K et al. (1998). Ipamorelin, the first selective growth hormone secretagogue. European Journal of Endocrinology. (PMID: 9849832)
Teichman SL et al. (2006). Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295 in healthy adults. (CJC-1295 pharmacokinetic characterization)

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Disclaimer. CJC-1295 and Ipamorelin are research compounds sold by MOG Research for laboratory and scientific research purposes only. Not intended for human or animal consumption. Not drugs, not FDA approved, not for therapeutic use. References to receptor pharmacology and published preclinical literature do not constitute medical or dosing guidance.

_For research use only. Not for human or animal consumption._