What is the difference between a GHRH analogue and a GHRP?

They reach the pituitary through different receptors. A GHRH analogue, such as CJC-1295 or Tesamorelin, mimics growth hormone-releasing hormone and acts on the GHRH receptor. A GHRP, such as Ipamorelin, acts on the ghrelin receptor (GHS-R1a). Both result in growth hormone release, but through independent pathways.

Why are CJC-1295 and Ipamorelin studied together?

Because they act on separate pathways, so research can examine what happens when both are engaged at once — something neither achieves alone. The GHRH plus GHRP pairing has been the reference combination in growth hormone research since the early 2000s.

Why would you not pair CJC-1295 with Tesamorelin?

They are both GHRH analogues, so they act on the same receptor rather than complementing each other. The rationale for pairing depends on the two compounds using different pathways, which is not the case here.

What does “No DAC” mean in CJC-1295 (No DAC)?

DAC stands for Drug Affinity Complex, a modification that greatly extends the original compound’s half-life. The No DAC version omits it, producing a shorter and more controlled release profile. The two versions are often confused but behave differently over time.

Which of the three has the strongest evidence base?

Tesamorelin, by a clear margin — it is the only GHRH analogue with FDA approval and has multiple Phase 3 trials behind it. Ipamorelin has a substantial preclinical literature dating to its characterisation at Novo Nordisk in 1998. CJC-1295 has the smallest published record of the three.

Research Library›Comparisons›CJC-1295 vs Ipamorelin vs Tesamorelin

Growth Hormone Comparison

CJC-1295 vs Ipamorelin vs Tesamorelin: Two Different Doors to the Same Room

All three prompt the pituitary to release growth hormone, which is why they get lumped together. But they do not use the same pathway — and that difference is why two of them are studied as a pair rather than as alternatives.

8 min read·5 studies cited·Updated July 2026

Quick Reference

CJC-1295	GHRH analogue — extends the GH signal
Tesamorelin	GHRH analogue — stabilised, full 44 amino acids
Ipamorelin	GHRP — ghrelin receptor, separate pathway
Key point	GHRH and GHRP are different doors, not rivals
Status	Research use only — not TGA approved

The Short Answer

Two of these are the same kind of compound and one is not. CJC-1295 and Tesamorelin are both GHRH analogues — synthetic versions of growth hormone-releasing hormone, the body’s own signal telling the pituitary to release GH. Ipamorelin is a GHRP, acting instead on the ghrelin receptor.

That is why CJC-1295 and Ipamorelin are so often studied together while CJC-1295 and Tesamorelin are not: the first pair approach the pituitary through two separate pathways, whereas the second pair are two versions of the same approach.

	CJC-1295 (No DAC)	Tesamorelin	Ipamorelin
Class	GHRH analogue	GHRH analogue	GHRP / ghrelin receptor agonist
Pathway	GHRH receptor	GHRH receptor	GHS-R1a (ghrelin receptor)
Acts on	Duration of the GH signal	Duration, with enhanced stability	Amplitude of each GH pulse
Structure	Modified GHRH fragment (1–29)	Stabilised full-length GHRH (1–44)	Selective pentapeptide
Selectivity note	GHRH-specific	GHRH-specific	Studied for minimal cortisol/prolactin effect
Commonly paired with	Ipamorelin (different pathway)	Studied alone	CJC-1295 (different pathway)

Two Pathways, Not Two Strengths

The pituitary releases growth hormone in pulses rather than continuously, and two separate upstream signals govern those pulses. Understanding that is the whole comparison.

Two doors, in plain language: imagine the pituitary as a room with two separate doors, each with its own bell. Ring either one and someone inside sends out growth hormone. The GHRH door is the main entrance — that is where CJC-1295 and Tesamorelin knock. The ghrelin door is round the side, and that one belongs to Ipamorelin. Ring a single bell over and over and the response is limited; there is only so much attention one door can command. Ring both at once and the room answers differently than it would to either alone. That is the whole logic behind pairing a GHRH analogue with a GHRP — and equally the reason pairing CJC-1295 with Tesamorelin adds little, because both would be standing at the same door pressing the same bell.

The GHRH pathway is the primary instruction to release GH. A GHRH analogue like CJC-1295 or Tesamorelin extends and reinforces that instruction, which research describes in terms of how long the release signal persists.

The ghrelin receptor pathway is separate. Ghrelin — better known as a hunger hormone — also triggers GH release through its own receptor. Ipamorelin acts here, and research examines its influence on how large each individual pulse is.

Why the GHRH + GHRP pairing became standard: because the two pathways are independent, acting on both is studied for producing a GH release pattern that neither produces alone. This is why the CJC-1295 + Ipamorelin combination has served as the reference pairing in growth hormone research for two decades.

Pairing two GHRH analogues would not do this — they would be competing for the same receptor rather than complementing each other.

CJC-1295 vs Tesamorelin: Same Class, Different Molecule

If both are GHRH analogues, the natural question is what separates them. Two things: structure and regulatory standing.

Structurally, CJC-1295 (No DAC) is based on the first 29 amino acids of GHRH — the fragment carrying the receptor activity — with modifications to resist enzymatic breakdown. Tesamorelin is the full 44-amino-acid sequence with a stabilising modification, making it a closer copy of the native hormone.

In regulatory terms they are far apart. Tesamorelin is the only GHRH analogue to have gained FDA approval, supported by multiple Phase 3 trials. CJC-1295 has no such approval and its literature is smaller and largely preclinical.

The "No DAC" in CJC-1295 (No DAC) matters too. The original CJC-1295 included a Drug Affinity Complex extending its half-life considerably; the No DAC version omits it, giving a shorter, more controlled release pattern. The two are frequently conflated but behave differently over time.

Frequently Asked Questions

Compiled by the Southern Pacific Labs research team. Last updated July 2026.

Browse the research range →

Published References

Raun K, Hansen BS, Johansen NL, et al. “Ipamorelin, the first selective growth hormone secretagogue.” European journal of endocrinology, 1998. PubMed
Teichman SL, Neale A, Lawrence B, et al. “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.” The Journal of clinical endocrinology and metabolism, 2006. PubMed
Falutz J, Allas S, Blot K, et al. “Metabolic effects of a growth hormone-releasing factor in patients with HIV.” The New England journal of medicine, 2007. PubMed
Sigalos JT, Pastuszak AW. “The Safety and Efficacy of Growth Hormone Secretagogues.” Sexual medicine reviews, 2018. PubMed
Stanley TL, Falutz J, Marsolais C, et al. “Reduction in visceral adiposity is associated with an improved metabolic profile in HIV-infected patients receiving tesamorelin.” Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2012. PubMed