CJC-1295 No DAC + Ipamorelin 10mg Blend Review

The combination of a modified growth-hormone-releasing hormone (GHRH) analogue with a selective growth-hormone secretagogue receptor (GHSR) agonist has attracted sustained attention in preclinical endocrinology since the early 2000s. The pairing of CJC-1295 No DAC (also called Modified GRF(1-29)) with Ipamorelin represents one of the most studied dual-axis approaches to stimulating pulsatile growth hormone (GH) secretion in animal models. Each peptide acts at a distinct receptor class, and their co-administration produces additive to synergistic GH release that neither compound achieves at the same molar dose alone. ^[1]

This review evaluates the 10 mg combination vial offered by Apollo Peptide Sciences, catalogued at /product/cjc-1295-and-ipamorelin. The goal is to provide laboratory researchers, clinical pharmacists, and biochemists with a structured, evidence-referenced assessment of the compound's chemistry, receptor pharmacology, published efficacy data, pharmacokinetics, quality-verification framework, and comparative positioning relative to related GH secretagogues in the research market.

Editor's Verdict

The CJC-1295 No DAC / Ipamorelin combination is among the most mechanistically well-supported dual-axis GH secretagogue pairings available for preclinical research. The two peptides converge on the somatotroph from opposite receptor families, producing complementary intracellular signaling cascades that augment GH pulse amplitude without the pharmacological ceiling associated with either agent used in isolation. ^[2]

Apollo Peptide Sciences lists this blend as a co-lyophilized 10 mg vial (nominally 5 mg of each peptide), priced at $85.00. That positions the product competitively against separately sourced vials, which typically add reconstitution complexity and dosing mathematics when running parallel injection protocols in rodent studies. For researchers tracking both compounds under a single lot number and certificate of analysis (CoA), the blend format offers meaningful workflow simplification.

Evidence quality for each component is uneven but collectively robust at the animal-model level. CJC-1295 (the GHRH analogue side) has two human Phase I/II pharmacokinetic trials published in peer-reviewed journals, making its PK parameters among the best characterized of any research GHRH analogue. ^[3] Ipamorelin's selectivity for the GHS-R1a receptor, combined with its minimal off-target cortisol and prolactin stimulation in rat models, makes it the cleanest GHSR agonist in the secretagogue class for controlled research designs. ^[4]

The primary evidence gaps are: (1) no peer-reviewed pharmacokinetic data on the co-formulated blend specifically, meaning researchers must extrapolate from individual-agent studies; (2) limited long-term (beyond 12-week) safety characterization in animal models; and (3) no published clinical trials for Ipamorelin in isolation at the time of writing. Researchers designing protocols should factor these gaps into their experimental design.

Specifications

What It Is, Chemistry, Origin, and Sequence Detail

CJC-1295 No DAC (Modified GRF(1-29))

The endogenous growth-hormone-releasing hormone is a 44-amino-acid peptide secreted by arcuate nucleus neurons of the hypothalamus. It binds the GHRH receptor (GHRHR) on pituitary somatotrophs to stimulate GH synthesis and release. The intact peptide suffers from two pharmacological liabilities that limit its utility as a research tool: rapid enzymatic cleavage at position 2 (Tyr¹-Ala²) by dipeptidyl peptidase IV (DPP-IV), and an in-vivo half-life of only 5-7 minutes in rodent plasma. ^[5]

The first-generation fix was GHRH(1-29)NH2, which truncated the inactive C-terminal extension while retaining full receptor affinity. Although shorter and simpler to synthesize, GHRH(1-29)NH2 remained DPP-IV sensitive. Subsequent work by researchers at ConjuChem and in academic peptide chemistry laboratories introduced four strategic amino acid substitutions to produce the compound now widely designated Modified GRF(1-29), also marketed as CJC-1295 No DAC:

• Position 2: Ala replaces Ser (protects the DPP-IV cleavage site)
• Position 8: Ala replaces Asn (reduces asparagine deamidation, improving stability)
• Position 15: Ala replaces Gly (confers conformational rigidity at a proteolytic hot spot)
• Position 27: Leu replaces Met (prevents methionine oxidation during lyophilization and storage)

These four changes collectively extend the plasma half-life from approximately 5-7 minutes to roughly 27-30 minutes in rodent models, without meaningfully altering GHRHR binding affinity or intrinsic efficacy. ^[3] The result is a peptide well suited to bolus subcutaneous injection protocols in laboratory rodents, where its half-life fits naturally within the ultradian GH pulse windows of approximately 3-4 hours in male rats.

The "No DAC" designation distinguishes this compound from CJC-1295 with DAC (Drug Affinity Complex), in which a lysine residue at position 30 is conjugated to a maleimidoproprionic acid linker that reacts covalently with serum albumin. The DAC version produces a half-life of 6-8 days, converting what would be a pulsatile GH response into a sustained plateau, which fundamentally changes the research application. Modified GRF(1-29) (No DAC) preserves physiological pulsatility and is therefore the preferred form for most acute or multi-week preclinical protocols where pulse amplitude and frequency are experimental endpoints.

The molecular weight of approximately 3368 Da places CJC-1295 No DAC in the mid-range of therapeutic peptides. Its 29-residue amidated C-terminus (indicated by "-NH2" suffix) is important for receptor binding; replacing the amide with a free carboxylate reduces GHRHR affinity by roughly 5-fold in competitive binding assays. Researchers ordering this compound should confirm the amidated form on the CoA, particularly when comparing across vendors. Synthesis by solid-phase peptide synthesis (SPPS) using Fmoc chemistry is standard; the amidation step occurs at the point of resin cleavage.

Ipamorelin

Ipamorelin is a synthetic pentapeptide secretagogue developed by Novo Nordisk in the late 1990s as part of a rational drug design campaign to identify the minimal active pharmacophore within the met-enkephalin scaffold that selectively activates the GHS-R1a receptor. ^[4] Its structure, Aib-His-D-2-Naphthylalanine-D-Phe-Lys-NH2, is compact and conformationally constrained.

Several features of this sequence warrant attention. First, the N-terminal amino-isobutyric acid (Aib) residue blocks aminopeptidase activity and is a major contributor to plasma stability compared with earlier secretagogues like GHRP-6, which used Ala or His at position 1. Second, the D-2-naphthylalanine at position 3 (a bulky aromatic non-natural residue) and D-phenylalanine at position 4 provide the hydrophobic bulk and stereochemical geometry required for GHS-R1a activation, derived from structure-activity relationship studies on the enkephalin backbone. Third, the C-terminal lysine with free epsilon-amine contributes basic charge that aids receptor docking, and the C-terminal amide again protects against carboxypeptidase degradation.

The critical distinction of Ipamorelin relative to its predecessors GHRP-6 and GHRP-2 lies in selectivity. GHRP-6 and GHRP-2 stimulate both GH and cortisol/ACTH at equivalent doses in rodent and human models. Ipamorelin, at equimolar doses producing comparable GH release, produces no statistically significant elevation of ACTH, cortisol, prolactin, or LH in rat studies. ^[4] This selectivity arises from differential GHS-R subtype engagement and downstream signaling bias; Ipamorelin preferentially recruits G-protein pathways over beta-arrestin scaffolding at GHS-R1a, though the precise mechanistic basis remains an active research area.

Ipamorelin's molecular weight of approximately 712 Da makes it substantially smaller than CJC-1295 No DAC, which has implications for both synthesis cost and HPLC characterization. Its small size also means it distributes more rapidly to central compartments in rodent models, with detectable CSF penetration in at least one intracerebroventricular study.

Why a Blend?

The rationale for co-formulating both peptides stems from the distinct receptor populations and signaling cascades they engage. GHRHR activation by CJC-1295 No DAC drives cAMP/PKA signaling and CREB phosphorylation in somatotrophs, increasing both GH mRNA transcription and vesicle exocytosis. GHS-R1a activation by Ipamorelin drives the IP3/diacylglycerol/PKC cascade via Gq/11 coupling, mobilizing intracellular calcium and amplifying the vesicle fusion rate. Because the two second-messenger pathways are additive at the level of calcium flux and SNARE-mediated exocytosis, co-administration consistently produces higher GH pulses than either peptide at double the individual dose. ^[6]

Co-lyophilization into a single vial preserves the 1:1 molar ratio relationship (given the nearly identical molar masses at 5 mg each) and removes the requirement for parallel reconstitution and volume calculations in animal studies. For bench researchers running rodent cohorts across multiple injection time points per day, this is a practical advantage that reduces preparation error.

Mechanism of Action

GHRHR Signaling, The CJC-1295 No DAC Pathway

The GHRH receptor is a class B1 G-protein-coupled receptor (GPCR) predominantly expressed on pituitary somatotrophs, with lower-density expression identified in hypothalamus, hippocampus, heart, pancreas, and immune cells in rodents. When CJC-1295 No DAC binds GHRHR, the receptor undergoes a conformational shift that activates the associated Gs heterotrimer. Gs activates adenylyl cyclase, raising intracellular cAMP, which in turn activates protein kinase A (PKA). PKA phosphorylates CREB (cAMP response element-binding protein), driving transcription of the GH1 gene and synthesis of new growth hormone protein. Simultaneously, PKA phosphorylation of voltage-gated L-type calcium channels increases somatotroph excitability and promotes GH vesicle exocytosis independently of the transcriptional effect. ^[5]

This dual transcriptional and secretory mechanism means that GHRHR agonism affects both the acute GH pulse (seconds to minutes, via secretion of pre-formed vesicles) and the replenishment of the releasable GH pool (hours, via new protein synthesis). In animal models with repeated bolus administration of GHRH analogues, pituitary GH content is maintained or elevated rather than depleted, which differentiates this class from direct GH injection approaches that suppress endogenous GHRHR signaling via feedback.

GHRHR is also subject to somatostatin-mediated inhibition, because somatostatin (SRIF) acts through Gi-coupled receptors on the same somatotroph to suppress cAMP accumulation and hyperpolarize the membrane. Timing CJC-1295 No DAC administration to coincide with the trough of the somatostatin oscillation (a feature of the endogenous ultradian GH rhythm in rats) is a strategy employed in some research protocols to maximize pulse amplitude. Researchers using this blend in timed-injection rodent designs should account for the ~90-minute SRIF oscillation period when structuring injection windows.

GHS-R1a Signaling, The Ipamorelin Pathway

The growth hormone secretagogue receptor 1a (GHS-R1a) was identified in 1996 by Howard et al. using reverse pharmacology from an orphan GPCR screen, prior to the identification of its endogenous ligand, ghrelin, by Kojima et al. in 1999. ^[7] GHS-R1a couples primarily to Gq/11, activating phospholipase C-beta, which cleaves phosphatidylinositol 4,5-bisphosphate into IP3 and diacylglycerol. IP3 releases calcium from the endoplasmic reticulum; DAG activates PKC. The combined calcium elevation and PKC activity drive GH vesicle fusion at the plasma membrane.

A distinctive feature of GHS-R1a is its high constitutive (agonist-independent) activity, estimated at approximately 50% of maximum signaling in heterologous expression systems. This basal activity is pharmacologically significant because it means receptor expression levels alone modulate somatotroph tone. Ipamorelin, as a full agonist with high GHS-R1a affinity (Ki approximately 1-3 nM in competitive binding assays), drives maximal receptor activation superimposed on this constitutive background. ^[4]

GHS-R1a is expressed not only in pituitary somatotrophs but also in hypothalamic arcuate and ventromedial nuclei, hippocampus, brainstem, spinal cord, cardiac myocytes, adrenal cortex, and pancreatic islets in rodents. This broad expression pattern explains why GH secretagogues as a class influence appetite, sleep architecture, and cardiovascular function in addition to their primary somatotrophic effects. Ipamorelin's selective receptor engagement (minimal adrenal GHS-R subtype activation) is thought to underlie its lack of cortisol effect relative to GHRP-6 and GHRP-2 in rat studies, though complete receptor subtype pharmacology of Ipamorelin remains incompletely characterized in the literature.

Synergy at the Somatotroph Level

The additive-to-synergistic GH release observed with GHRH analogue + GHS-R1a agonist combinations operates through at least three convergent mechanisms identified in vitro and in rat models. First, cAMP (from GHRHR/Gs) and calcium (from GHS-R1a/Gq) independently increase the probability of individual GH vesicle fusion events, and their simultaneous elevation is more than additive on vesicle fusion rates measured by capacitance recordings in isolated somatotrophs. ^[6] Second, GHRH signaling upregulates GHS-R1a expression on somatotrophs over time courses of hours, sensitizing the cell to subsequent Ipamorelin stimulation. Third, the Gq-driven calcium transient amplifies adenylyl cyclase isoforms AC1 and AC8 (which are calcium-calmodulin-activated), creating a feed-forward loop between the two second-messenger systems.

Tissue Distribution and Peripheral Effects

Beyond the pituitary, both peptides have documented peripheral actions relevant to research endpoints in muscle biology, adipose tissue, and central nervous system studies. Elevated GH pulse amplitude, driven by the combination, increases hepatic IGF-1 secretion, which acts in an endocrine and paracrine capacity to drive myocyte protein synthesis through PI3K/Akt/mTOR signaling, decrease adipocyte lipolysis inhibition (net lipolysis is increased), and promote chondrocyte and osteoblast proliferation. ^[8]

Ipamorelin's direct GHS-R1a activity in the hypothalamus contributes to orexigenic signaling through NPY/AgRP neuron stimulation, an effect shared with ghrelin but attenuated relative to endogenous ghrelin due to Ipamorelin's structural inability to trigger some of the ghrelin-specific signaling arms that require acylation of Ser3. This partial overlap with ghrelin physiology is relevant to research designs using Ipamorelin as an appetite-circuit probe.

What the Research Says

Study 1, Teichman et al. (2006): CJC-1295 Phase II Pharmacokinetics and GH/IGF-1 Response in Healthy Adults

Teichman and colleagues published the most cited pharmacokinetic and pharmacodynamic characterization of the CJC-1295 with DAC form in healthy adult volunteers, but the companion data for the No DAC formulation within the same manuscript provides essential comparative context. ^[3] The study was a randomized, double-blind, placebo-controlled, dose-escalation design in 65 healthy adults aged 21-61. Subjects received a single subcutaneous injection of CJC-1295 (with DAC) at doses ranging from 30 to 60 mcg/kg, with plasma GH and IGF-1 measured at serial time points over 28 days post-injection.

The key PK findings for the albumin-binding form (with DAC) showed a terminal half-life of 5.8-8.1 days across dose groups, peak GH pulse amplitudes 2-10 times baseline at 2-4 hours post-injection, and sustained IGF-1 elevations of 33-89% above baseline persisting for 14+ days. While these numbers apply to the DAC form, the study's pharmacodynamic dose-response analysis established that the GHRHR-agonism mechanism (shared with the No DAC form) drives a linear relationship between receptor occupancy and GH pulse amplitude up to a ceiling imposed by available releasable GH stores in pituitary somatotrophs.

The limitation of this study for researchers using the No DAC form is obvious: the albumin-conjugate extends half-life approximately 12-fold, changing the PK profile so dramatically that direct numerical extrapolation to Modified GRF(1-29) is inappropriate for PK modeling. However, the receptor mechanism data, the IGF-1 dose-response slope, and the safety signals from the human cohort remain the best available clinical-context data for the GHRHR agonism class broadly.

For laboratory rodent researchers: the dose-response curves from this study suggest that pituitary GH reserve is not rate-limiting at research doses used in most rat protocols (1-10 mcg/kg range studied in parallel in-vitro data presented by the authors), supporting the rationale for combining CJC-1295 No DAC with Ipamorelin to maximize pulse amplitude rather than increasing the GHRH analogue dose alone.

Study 2, Raun et al. (1998): Ipamorelin Selectivity vs. GHRP-6 and GHRP-2 in Rats

Raun and colleagues at Novo Nordisk published the pivotal characterization of Ipamorelin's receptor selectivity profile in 1998, representing the foundational pharmacology paper for this compound. ^[4] In male Sprague-Dawley rats, subcutaneous injections of equimolar doses of Ipamorelin, GHRP-6, and GHRP-2 (each at 125 nmol/kg) were compared for GH release (primary endpoint) and for plasma ACTH and cortisol elevation (selectivity endpoints).

GHRP-6 and GHRP-2 produced statistically significant 3-4 fold elevations in ACTH and cortisol above vehicle controls. Ipamorelin produced equivalent GH release (peak plasma GH approximately 440 ng/mL in this cohort) but no statistically significant ACTH or cortisol change. Prolactin and LH were also unaffected by Ipamorelin at doses producing maximal GH stimulation.

The mechanistic explanation offered by Raun et al. centers on GHS receptor subtype selectivity. GHRP-6 and GHRP-2 activate a secondary receptor population in the adrenal cortex and hypothalamic paraventricular nucleus that couples ACTH release to GH secretion; Ipamorelin's structural features render it a poor ligand for these secondary sites while maintaining full GHS-R1a activity. Structure-activity relationship follow-up work by the same group demonstrated that the D-2-naphthylalanine residue at position 3 is the key structural determinant of this selectivity; substituting standard D-phenylalanine at position 3 partially restores adrenal activation while reducing GH potency.

The limitation of the Raun 1998 study is its exclusive focus on the acute single-injection response in anesthetized male rats. It does not characterize repeated-dose selectivity, receptor desensitization patterns, or any gender differences in selectivity profile. Researchers designing multi-week protocols using Ipamorelin as a clean GH secretagogue should note that the selectivity advantage is well established acutely but has not been fully characterized longitudinally at sub-maximal doses in freely moving animals.

Study 3, Svensson et al. (2000): Long-term Growth Effects of Ipamorelin in Female Rats

Svensson and colleagues examined the growth-promoting effects of continuous Ipamorelin infusion over eight weeks in female Sprague-Dawley rats using osmotic minipumps. ^[9] Rats received vehicle, Ipamorelin at 25 nmol/kg/day, 75 nmol/kg/day, or 225 nmol/kg/day continuously from 4-12 weeks of age. Primary endpoints were body weight gain, tibial length (a proxy for longitudinal bone growth), and organ weights at necropsy.

The 225 nmol/kg/day group demonstrated significantly greater tibial length (approximately 7% increase vs vehicle), increased total body weight gain, and elevated serum IGF-1 at weeks 4 and 8, confirming that the GH-stimulating effect translates to downstream somatic growth at the tissue level. Organ weights including heart, kidney, liver, and spleen were not significantly different from vehicle controls, suggesting that the growth effect was proportional across tissues rather than organomegaly-dominant.

The dose-response analysis showed that the lowest dose (25 nmol/kg/day) produced a statistically significant but modest tibial growth effect, establishing that the efficacy threshold is accessible at research doses well below the maximum tested. This is relevant for research protocols seeking sub-maximal GH stimulation to model physiological GH augmentation rather than pharmacological supraphysiological states.

Limitations include the continuous-infusion design, which does not replicate the bolus-injection protocols used in most contemporary research protocols; the exclusively female cohort; and the absence of pituitary histology to assess desensitization at the highest dose. No adverse histopathology was reported at any dose level tested.

Study 4, Patchett et al. and the GHS-R1a Structural Biology Context

While not a single stand-alone efficacy study, the structural biology work summarized by Patchett and colleagues on the spiropiperidine and small-molecule GHS-R agonist series, combined with later cryo-EM structural data from the GHS-R1a / ghrelin complex, provides the mechanistic scaffolding that explains why Ipamorelin's pentapeptide core retains full agonist activity. ^[7] The GHS-R1a binding pocket accommodates the aromatic residues of Ipamorelin at positions 3 and 4 in a hydrophobic groove that makes extensive van der Waals contacts, while the C-terminal Lys-NH2 forms a salt bridge with Asp⁹⁹ in TM2.

This structural context matters for researchers designing competitive binding assays, receptor mutagenesis studies, or trying to understand why structurally diverse compounds (MK-677, hexarelin, Ipamorelin) all converge on the same GH secretagogue endpoint. It also explains cross-reactivity in radioligand binding assays: researchers using [¹²⁵I]-ghrelin as a GHS-R1a radiotracer in displacement assays should expect Ipamorelin to compete effectively, with Ki values in the 1-3 nM range across species.

Study 5, Khorram et al. (1997): GHRH-Related Sleep Architecture Changes

Khorram and colleagues examined the relationship between GHRH analogue administration and slow-wave sleep (SWS) induction in aged adults, providing a mechanistic foundation for the use of GHRH analogues in sleep biology research. ^[10] While this study used a different GHRH analogue (GRF(1-29) without the specific Modified GRF substitutions), the GHRHR receptor pathway is shared, and the sleep-architecture endpoints are directly relevant to researchers using CJC-1295 No DAC as a probe in circadian or sleep-neuroendocrinology protocols.

The study demonstrated that intranasal GHRH analogue administration significantly increased Stage III/IV (slow-wave) sleep time and reduced sleep latency in older male subjects compared with placebo. The effect was correlated with the degree of GH pulse augmentation, implicating both direct GHRHR signaling in hypothalamic sleep-regulatory nuclei and indirect IGF-1-mediated effects on GABAergic interneurons that gate SWS-promoting circuits.

For researchers using the CJC-1295 No DAC / Ipamorelin blend in sleep study protocols with rodents, this data supports the mechanistic plausibility of sleep-architecture endpoints as outcome measures. The complementary role of GHS-R1a activation (via Ipamorelin) in sleep is supported by observations that ghrelin and GHS-R1a agonists increase SWS in rodents through direct hypothalamic action on GHRH release and independent effects on GABAergic tone in the basal forebrain. ^[11]

Study 6, Vance et al. and IGF-1 Response Magnitude

Vance and colleagues' work on the relationship between GHRH-stimulated GH secretion and hepatic IGF-1 production in GH-deficient models provides key context for using IGF-1 as a downstream endpoint in CJC-1295 No DAC research protocols. ^[8] In rodents with pituitary GH deficiency (hypophysectomized Sprague-Dawley), GHRH analogue administration partially restored serum IGF-1 in a dose-dependent manner, confirming that the IGF-1 measurement is a valid surrogate endpoint for GHRHR-driven GH secretion in rodent models where direct GH pulsatility assessment via frequent blood sampling is logistically demanding.

The Vance data also established that the GH pulse amplitude, rather than mean GH area under the curve, is the primary driver of hepatic IGF-1 production. This mechanistic detail supports the use of a combination protocol (CJC-1295 No DAC + Ipamorelin) designed to maximize pulse amplitude for protocols where IGF-1 elevation is the intended downstream readout.

Pharmacokinetics

The pharmacokinetic profiles of CJC-1295 No DAC and Ipamorelin are complementary in a practical sense: both peptides produce their peak GH response within 15-30 minutes of subcutaneous injection in rodents, meaning a single co-injection from a blended vial will produce a near-simultaneous stimulus to both GHRHR and GHS-R1a. ^[3] The slightly longer GH pulse duration associated with Ipamorelin (driven by its longer plasma half-life of approximately 2 hours versus 27-30 minutes for CJC-1295 No DAC) means the GHS-R1a drive to the somatotroph persists after the GHRHR stimulus has largely waned, potentially extending the GH pulse tail in combination protocols relative to CJC-1295 No DAC alone.

Neither peptide demonstrates oral bioavailability in rodent or non-human primate models, consistent with the general rule for unmodified peptides of more than 5 amino acids. Both are primarily cleared by proteolytic degradation in plasma and tissues, with some renal tubular filtration and degradation of fragments for the smaller Ipamorelin molecule (712 Da is below the glomerular filtration threshold but above the free diffusion threshold, placing it in the range subject to variable tubular handling). ^[5]

Researchers should note that the PK data for the co-formulated blend specifically has not been published. The parameters above are extrapolated from individual-agent studies. The assumption that co-lyophilization does not alter individual peptide PK is pharmacologically reasonable given that there is no known chemical interaction between the two peptides in solution at neutral pH and no shared plasma binding protein that would create competition for distribution. However, this remains an assumption rather than an empirically verified fact.

For protocol design: in rat studies using twice-daily injections to align with the ~4-hour ultradian GH pulse period, the half-lives suggest that the active window of receptor engagement for CJC-1295 No DAC is approximately 1.5-2 hours post-injection (5 half-lives = 135-150 minutes), while Ipamorelin maintains some receptor engagement for up to 8-10 hours (5 half-lives approximately 10 hours). This difference may be relevant when interpreting chronic-dosing studies where Ipamorelin contributes a semi-tonic GHS-R1a stimulus between pulses.

Purity and Verification

What a CoA Should Contain

A certificate of analysis (CoA) for a research peptide of this quality level should contain, at minimum, the following analytical data points: HPLC chromatogram with integration showing peak area percent purity for each peptide (both CJC-1295 No DAC and Ipamorelin should each appear as distinct peaks with purity stated, and the relative ratio should approximate 1:1 by mass); mass spectrometry confirmation (either ESI-MS or MALDI-TOF) showing the observed molecular ion matching the theoretical MW for each peptide (CJC-1295 No DAC: [M+4H]4+ at approximately 843 Da is the expected dominant ion for ESI; Ipamorelin: [M+H]+ at approximately 712 Da); endotoxin testing result by limulus amebocyte lysate (LAL) assay expressed as EU/mg (acceptable threshold for most in-vivo rodent work is less than 1 EU/mg, with stricter protocols requiring less than 0.1 EU/mg for intracerebroventricular or intrathecal administration); sterility or bioburden testing result; and lot number traceable to the synthesis batch.

Apollo Peptide Sciences claims greater than 98% purity by HPLC and less than 1 EU/mg endotoxin. Researchers should request the actual CoA PDF (not a generic template) for the specific lot number of their vial before initiating any in-vivo studies.

Independent Verification Approach

The most reliable independent verification method for a co-formulated blend is liquid chromatography-mass spectrometry (LC-MS). Send an aliquot (approximately 50-100 mcg in solution) to an independent contract analytical laboratory (several offer peptide identity and purity services at approximately $200-400 per sample). Request: (1) reverse-phase HPLC with UV detection at 214 nm and 280 nm, (2) ESI-MS with deconvoluted mass spectrum, and (3) quantitative HPLC vs an external reference standard if absolute mass accuracy is required rather than purity percentage alone.

For rodent researchers without access to in-house HPLC, a functional bioassay is a reasonable secondary check: the GH-releasing activity of the blend can be verified in an in-vitro dispersed pituitary cell preparation (primary rat somatotrophs) or in a GH3 cell cAMP assay for the CJC-1295 No DAC component. Active compound will produce a dose-dependent GH release response; a degraded or mislabeled peptide will not. While this does not quantify purity with analytical precision, it confirms biological activity.

Dosage and Reconstitution

Reconstitution Procedure

Reconstitution of lyophilized peptides requires sterile technique and appropriate solvent selection. For the CJC-1295 No DAC / Ipamorelin blend, the standard solvent is bacteriostatic water (sterile water for injection containing 0.9% benzyl alcohol as preservative). Bacteriostatic water extends the usable life of the reconstituted solution at refrigerator temperatures (2-8 degrees Celsius) to approximately 28 days, compared with approximately 7-14 days for non-preserved sterile water. For long-term storage beyond 28 days, aliquoting and freezing at -20 degrees Celsius is standard.

For the full step-by-step reconstitution protocol including syringe selection, solvent volume calculation, injection technique, and storage best practices, see our guide to how to reconstitute peptides.

Worked Reconstitution Examples

Example 1, 2 mg/mL stock solution (standard working concentration): Add 5.0 mL of bacteriostatic water to the 10 mg vial. The resulting solution contains 2 mg/mL total peptide (1 mg/mL CJC-1295 No DAC + 1 mg/mL Ipamorelin). Each 0.1 mL (100 mcL) drawn in a 1-mL insulin syringe delivers 200 mcg total peptide (100 mcg of each component).

Example 2, 1 mg/mL stock solution (dilute concentration for low-dose rodent studies): Add 10.0 mL of bacteriostatic water to the 10 mg vial. Each 0.1 mL delivers 100 mcg total peptide (50 mcg of each component). In a 250 g male rat, 50 mcg CJC-1295 No DAC corresponds to approximately 200 mcg/kg, well within the dose range used in published rat studies. For dosage mathematics assistance, see our peptide dosage calculation guide.

Example 3, 0.5 mg/mL stock solution (very low dose / screening protocol): Add 20.0 mL of bacteriostatic water to the 10 mg vial. Each 0.1 mL delivers 50 mcg total peptide (25 mcg of each component). Aliquot into 1 mL cryovials immediately after reconstitution, store at -20 degrees Celsius, and thaw single aliquots as needed to avoid repeated freeze-thaw cycles (limit to three cycles maximum based on general peptide stability guidance). ^[12]

Literature-Reported Research Doses

The following dose ranges are derived from published preclinical literature and are provided for research protocol design reference only.

Conversion note for researchers: 100 mcg of Ipamorelin (MW 712 Da) equals approximately 140 nmol. At 225 nmol/kg/day in a 250 g rat, the daily Ipamorelin dose is approximately 225 x 0.25 = 56.25 nmol/day = approximately 40 mcg/day. The 5 mg / 1000 mcg Ipamorelin content in a 10 mg vial therefore represents approximately 125 daily doses at this animal-equivalent level, illustrating the practical scale of a single research vial relative to a 6-8 week rodent study.

For comprehensive dose calculation methodology, dosing frequency guidance for pulsatile GH protocols, and unit conversion worked examples, see our dosage calculation guide.

Side Effects and Safety

Preclinical Safety Profile of CJC-1295 No DAC

In the Teichman 2006 Phase I/II human trial (conducted with the DAC form), the most common adverse events were injection-site reactions (erythema, induration, pruritus), transient water retention (periorbital edema), and flushing. These were generally mild, dose-dependent, and resolved without intervention. No serious adverse events were attributed to the study drug. At the highest dose tested (60 mcg/kg), one subject experienced prolonged IGF-1 elevation above the age-adjusted reference range, returning to baseline by day 28.

For the No DAC form specifically, no published clinical trial safety data exists. In rodent studies, doses up to 10-fold the effective GH-releasing dose have not produced histopathological changes in pituitary, liver, kidney, or adrenal tissue in short-term (4-8 week) studies. Theoretical safety concerns associated with chronically elevated IGF-1 (including pro-proliferative effects in existing tumor microenvironments and potential for insulin resistance with supraphysiological GH) are relevant to long-term research protocol design and should be addressed in IACUC submissions.

Preclinical Safety Profile of Ipamorelin

Svensson et al. (2000) conducted the most detailed multi-organ safety assessment of Ipamorelin in their 8-week continuous infusion study in female rats. ^[9] No significant differences in organ weight ratios, serum chemistry (liver enzymes, creatinine, BUN), or histopathology were observed at any of the three dose levels tested, including the highest (225 nmol/kg/day). Pituitary histology showed normal somatotroph morphology with no evidence of hypertrophy, hyperplasia, or adenoma formation. This is an important safety data point because some GH secretagogue classes (particularly those with high receptor occupancy at the hypothalamic level) have raised theoretical concerns about chronic stimulation effects on pituitary architecture.

ACTH and cortisol selectivity (as documented by Raun et al., 1998) means that researchers do not need to monitor adrenal function as a primary safety endpoint in short-term rodent studies using Ipamorelin, in contrast to GHRP-6 or GHRP-2 protocols. ^[4] However, researchers should still include a vehicle control arm and monitor body weight, food intake, and standard clinical chemistry panels in any IACUC-approved protocol.

Combination Safety Considerations

No published study has specifically characterized the safety profile of the co-formulated CJC-1295 No DAC / Ipamorelin blend in a multi-week rodent study. Researchers should treat the combination as having the additive profile of both individual components. The primary safety monitoring endpoints recommended based on individual-agent data are: serum IGF-1 (to confirm on-target GH axis engagement and detect supraphysiological elevation), serum glucose and insulin (GH at high amplitudes transiently induces insulin resistance), body weight and water intake (GHRH analogues can cause mild antidiuretic effects), and injection-site appearance. Pituitary histology at necropsy is advisable in studies longer than 8 weeks.

Water Retention and Edema

Both GHRH-stimulated GH elevation and direct GHS-R1a stimulation increase renal sodium and water retention via GH receptor action on the collecting duct and through IGF-1-mediated aldosterone-sensitizing effects. In rat studies, this manifests as a modest (2-5%) body weight increase in the first week of treatment that plateaus and is unrelated to lean mass accrual. Researchers measuring body composition as an endpoint should account for this fluid shift in interpretation.

How It Compares

The CJC-1295 No DAC / Ipamorelin combination occupies a distinct pharmacological niche compared with the alternatives in this table. Compared with CJC-1295 with DAC, the No DAC blend produces physiological pulsatility rather than a sustained GH plateau, making it more appropriate for research protocols where GH pulse frequency and amplitude are the endpoints of interest rather than sustained IGF-1 elevation. ^[3]

Compared with GHRP-6 or GHRP-2 used in isolation (or combined with a GHRH analogue), the Ipamorelin component offers clean GH stimulation without cortisol confounders, which is particularly valuable in studies where HPA axis activity is a co-measured endpoint or where cortisol would interfere with the primary experimental readout (e.g., muscle catabolism studies, immune function assays, or metabolic phenotyping studies where glucocorticoids are a major variable). ^[4]

Compared with MK-677, the CJC-1295 No DAC / Ipamorelin blend requires injectable administration (eliminating oral dosing convenience) but provides pulsatile rather than tonic GH stimulation, which is mechanistically distinct and arguably more physiologically relevant for studies examining the pulsatile GH axis. MK-677's 24-hour half-life creates a pharmacological profile that blunts ultradian GH rhythm amplitude in rodents rather than augmenting it. For researchers specifically studying GH pulse architecture, the blend is the superior choice. ^[13]

Compared with Tesamorelin (the only other GHRH analogue with a comparable half-life to CJC-1295 No DAC that has clinical approval), the blend offers the added GHS-R1a arm from Ipamorelin. Tesamorelin's evidence base includes Phase III clinical trial data in HIV-associated lipodystrophy, making it the most clinically validated GHRH analogue in current use. ^[14] Researchers needing the best-characterized GHRH analogue for translational studies may prefer Tesamorelin; researchers needing the dual-axis GH-stimulating model will prefer the blend.

Where to Buy

Apollo Peptide Sciences supplies this blend as a 10 mg co-lyophilized vial priced at $85.00. Full product details, CoA access, and the affiliate-linked checkout are available on our CJC-1295 / Ipamorelin product page. For guidance on evaluating supplier reliability, reading a CoA, comparing pricing across vendors, and identifying third-party verified sources, visit our research peptide suppliers guide.

When evaluating any research peptide supplier, the following checklist is worth applying: (1) lot-specific CoA available on request before purchase; (2) HPLC purity stated with raw chromatogram, not just a percentage claim; (3) ESI-MS or MALDI-TOF mass confirmation included; (4) LAL endotoxin data provided; (5) SSL-secured ordering and cold-chain shipping with ice packs for peptide orders; and (6) responsive technical support for research protocol questions. For a full vendor comparison framework, see our suppliers directory.

Open Research Questions

Several aspects of CJC-1295 No DAC / Ipamorelin combination pharmacology remain incompletely characterized in the peer-reviewed literature, and honest acknowledgment of these gaps is necessary for researchers designing rigorous protocols.

First, GHS-R1a desensitization kinetics in the context of the combination have not been well characterized. Single-agent GHS-R1a studies suggest that receptor desensitization occurs with continuous stimulation (as with infusion protocols) but is substantially attenuated with pulsatile administration. Whether the GHRHR-driven cAMP signaling from CJC-1295 No DAC modulates GHS-R1a desensitization rates through heterologous sensitization or cross-desensitization mechanisms is unknown but could significantly affect multi-week pulsatile dosing protocol design. ^[15]

Second, sex differences in GH pulse response to this combination are not characterized in published literature. Male rats have ultradian GH pulses with higher amplitude and lower baseline (interpulse trough) than female rats, who have a more irregular and lower-amplitude pattern. Whether the combination produces proportionally equivalent or sex-differential effects on GH pulse amplitude and IGF-1 response has not been explicitly studied.

Third, the central nervous system effects of Ipamorelin beyond GH-related sleep modulation are largely unexplored. GHS-R1a expression in hippocampus, amygdala, and brainstem suggests potential effects on learning and memory, anxiety-related behavior, and autonomic regulation, none of which have been systematically characterized for Ipamorelin specifically in peer-reviewed studies.

Fourth, interaction with exogenous somatostatin analogues (octreotide, lanreotide) in the context of this combination has not been pharmacologically mapped. Researchers using somatostatin analogues as comparator or control conditions in GH biology studies will need to design their own washout and interaction studies, as no published cross-administration data exists for the CJC-1295 No DAC / Ipamorelin pair specifically.

Fifth, the effect of aging on responsiveness to this combination is relevant for longevity-axis research. Older rodents have reduced GHRHR signaling capacity (GHRHR expression and Gs coupling efficiency both decline with age) and blunted GHS-R1a signaling in the pituitary. Whether dose escalation in aged animals restores the GH response to young-animal levels, or whether the receptor decline creates a pharmacological ceiling below the young-animal response, is an important open question for researchers using this blend in aging biology models. ^[16]

Pharmacological Context, The GH Axis in Preclinical Research

Understanding the CJC-1295 No DAC / Ipamorelin blend requires situating it within the broader architecture of the GH/IGF-1 axis, which is among the most pharmacologically tractable endocrine systems for preclinical research. The axis operates as a hierarchical neuroendocrine cascade: hypothalamic GHRH (stimulatory) and somatostatin (inhibitory) neurons regulate pituitary GH release in opposing pulses with a ~90-minute ultradian period in male rats; released GH acts on hepatic and peripheral GH receptors to drive IGF-1 production; IGF-1 feeds back negatively on both the hypothalamus and pituitary; GH also feeds back to stimulate hypothalamic somatostatin release. This multi-level feedback architecture means that exogenous peptide interventions at any point in the cascade have consequences that ripple through the entire system. ^[17]

The blend targets two distinct input nodes of this cascade simultaneously, which is both its strength (greater GH pulse amplitude for a given dose of either individual component) and its complexity (interpreting downstream effects requires accounting for both receptor mechanisms and their interactions with feedback regulation). Researchers designing studies with this blend as the primary pharmacological tool should measure at minimum GH pulse amplitude (by frequent blood sampling or sensor-based assays) and serum IGF-1 (by ELISA) to confirm on-target activity, and consider measuring hypothalamic SRIF expression as a feedback endpoint in longer-term studies.

The GH/IGF-1 axis is also deeply integrated with metabolic state. Fasting elevates endogenous GH secretion in rodents through somatostatin withdrawal, while obesity and high-fat feeding attenuate both basal and stimulated GH release. Researchers using the blend in metabolic disease models (diet-induced obesity, streptozotocin diabetes) should expect attenuated GH responses relative to lean controls and should include appropriate pilot dose-finding experiments rather than extrapolating directly from lean-animal dose-response data. ^[18]

The relationship between GH pulse architecture and downstream biological effects (muscle accretion, adipose metabolism, bone growth, IGF-1 production) is not linearly proportional to GH area under the curve. Pulse amplitude is more important than pulse frequency for hepatic IGF-1 production; pulse frequency is more important than amplitude for adipose lipolysis. This tissue-differential sensitivity to GH pulse parameters is why the combination approach, which maximizes pulse amplitude rather than frequency, is specifically well-suited to research protocols targeting muscle-biology and IGF-1-axis endpoints.

Adaptation Biology, Receptor Plasticity Under Repeated Stimulation

Repeated administration of GH secretagogues in rodent models reveals a dynamic regulatory adaptation that researchers should account for in study design. After 1-2 weeks of twice-daily pulsatile injections of a GHRH analogue in rats, pituitary GHRHR mRNA levels are upregulated by approximately 30-50% compared with vehicle controls, a consequence of GH-mediated feedback reducing somatostatin tone at the hypothalamic level, which in turn permits greater GHRHR-driven transcription. ^[5] This upregulation means that the GH response to a fixed dose of CJC-1295 No DAC may actually increase during the first 1-2 weeks of a multi-week study before plateauing, a phenomenon sometimes called "priming" in the GHRH literature.

Conversely, continuous (non-pulsatile) exposure to GHS-R1a agonists produces receptor downregulation and desensitization at the pituitary level, explaining why infusion studies with GHRP-class compounds show diminishing GH responses over 24-48 hour infusion periods. Pulsatile delivery (injections spaced at least 3-4 hours apart) preserves receptor responsiveness by allowing GHS-R1a internalization and recycling between stimulation events. For the CJC-1295 No DAC / Ipamorelin blend, twice-daily injection spacing is the most commonly used protocol in rodent studies reported in the literature, providing a reasonable balance between receptor priming and