Mechanism — how Ipamorelin and CJC-1295 differ
Ipamorelin is a pentapeptide selective agonist at the ghrelin receptor (also known as the GHS-R1a or growth-hormone secretagogue receptor). Its proposed mechanism in research models is selective ghrelin-axis activation without meaningful effect on cortisol, prolactin or aldosterone release — which distinguishes it from earlier ghrelin-receptor agonists.
CJC-1295 is a 30-residue GHRH analogue acting at the GHRH receptor. The 'with DAC' variant adds a drug-affinity-complex modification that promotes covalent albumin binding and substantially extends the half-life; the 'no DAC' variant is the unmodified short analogue.
Receptor profile
Ipamorelin is selective for the ghrelin receptor — the selectivity profile is the engineering advantage over earlier ghrelin-receptor agonists like GHRP-6 or GHRP-2 which carry additional off-target effects.
CJC-1295 is selective for the GHRH receptor. The complementary receptor profile to ipamorelin is the reason the two are typically paired in research panels — combined ghrelin-axis and GHRH-axis activation produces a synergistic GH-release signal in research models.
Pharmacokinetics and half-life
Ipamorelin has a short native half-life — research cadences in published preclinical work are typically daily or sub-daily.
CJC-1295 no DAC sits in a similar daily-cadence window; CJC-1295 with DAC has a substantially longer half-life (multi-day) driven by covalent albumin binding through the DAC modification, suitable for weekly research cadences.
Research applications
Ipamorelin is used in research models of ghrelin-axis signalling, growth-hormone-axis research and selective-secretagogue-comparator studies. The clean selectivity profile makes it the reference compound for ghrelin-receptor research.
CJC-1295 (with or without DAC) is used in research models of GHRH-axis signalling, growth-hormone-axis research, and as the GHRH-arm in combined-axis panels with ipamorelin. The DAC variant is preferred when a sustained multi-day GHRH-axis signal is the experimental requirement.
Analytical specification on every Regena batch
Both Ipamorelin and CJC-1295 ship from Regena only after independent third-party verification — Janoshik Analytical is the default verifier, with orthogonal independent laboratories used when batch chemistry calls for confirmation by a second method. Minimum release specification is ≥99.0% HPLC main-peak purity with matching mass-spectrometry molecular weight and water content within the published specification for the compound.
Batch COAs for both compounds are published on the Regena lab reports page so a research-peptide buyer can audit the analytical detail before purchase. The /trust/how-to-read-a-coa reference walks through every field on a modern Regena COA.
Handling, reconstitution and stability
Both compounds ship lyophilised under nitrogen. Hold the unopened vial at 2–8 °C; freeze at −20 °C for long-term storage. Reconstitution with bacteriostatic water (0.9% benzyl alcohol) supports a 28-day in-use stability window under refrigeration for both compounds.
Aliquot before any freeze. The single most common cause of measurable potency loss in research peptides is repeat freeze-thaw cycling — both Ipamorelin and CJC-1295 benefit from single-thaw aliquot workflows. Vortex gently, never shake aggressively, and keep reconstituted vials away from direct light. The /research/compound-storage-guide reference covers the per-compound stability windows in detail.
When researchers choose Ipamorelin vs CJC-1295
Researchers choose ipamorelin when the protocol targets selective ghrelin-receptor signalling without GHRP-6 / GHRP-2 off-target effects. Researchers choose CJC-1295 when the protocol targets the GHRH axis specifically — no DAC for a pulsatile profile, with DAC for a sustained multi-day profile. Matched panels of ipamorelin + CJC-1295 are one of the most common growth-hormone-secretagogue research designs.
For multi-compound comparator studies, the Regena consultations team will reserve matched-batch inventory of both Ipamorelin and CJC-1295 against a project timeline so the experimental panel is sourced under a single analytical specification window.
Regulatory and research-use framing
Both Ipamorelin and CJC-1295 are supplied strictly for in-vitro and preclinical research use. They are not medicines, are not approved for human consumption in Spain, the United Kingdom, the European Union or the United States, and are not dispensed against a prescription. The research-use declaration ships with every package alongside the independent third-party COA.
Comparison pages on the Regena site exist for laboratory-research reference. Nothing on this page constitutes a recommendation for human use of either compound.
Frequently asked questions
What is the main difference between Ipamorelin and CJC-1295?+
Ipamorelin is a pentapeptide selective agonist at the ghrelin receptor (also known as the GHS-R1a or growth-hormone secretagogue receptor).
Which has the longer half-life, Ipamorelin or CJC-1295?+
Ipamorelin has a short native half-life — research cadences in published preclinical work are typically daily or sub-daily.
Are Ipamorelin and CJC-1295 the same compound class?+
Both sit in the growth-hormone secretagogues category but with distinct receptor profiles and pharmacokinetics — see the receptor-profile section above for the side-by-side detail.
What HPLC purity does Regena release each compound against?+
≥99.0% HPLC main-peak purity for both Ipamorelin and CJC-1295, with matching mass-spectrometry molecular weight and water content within the published specification for each compound.
Who independently verifies the batches?+
Janoshik Analytical is the default independent verifier for both compounds; orthogonal independent laboratories are used when batch chemistry calls for second-method confirmation.
Can I order matched batches for a comparator study?+
Yes — the Regena consultations team will reserve matched-batch inventory of both compounds against a project timeline so the experimental panel is sourced under a single analytical specification window.
Are these peptides approved for human use?+
No. Both are supplied strictly for in-vitro and preclinical research use. They are not medicines, are not approved for human consumption, and are not dispensed against a prescription.
Where can I see the current batch COAs for both compounds?+
On the /coa lab reports page, indexed by compound and batch number. New batches appear within 24 hours of independent release.
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