Ipamorelin
A synthetic growth hormone secretagogue and selective ghrelin-receptor (GHS-R1a) agonist. Its formal clinical development program was discontinued, leaving a literature of early-phase studies rather than an approved product.
CJC-1295 without DAC (Mod GRF 1-29)
The same GHRH 1-29 modification without the albumin-binding linker — often sold as "Mod GRF 1-29" — producing a shorter-acting GH stimulus closer to native GHRH kinetics.
Two receptors, one output
Ipamorelin is a synthetic ghrelin-receptor agonist — a GHRP-family secretagogue that stimulates GH release through the same receptor ghrelin uses. CJC-1295 (specifically Mod GRF 1-29) is a GHRH analog acting at the hypothalamic-pituitary level. Both converge on pituitary GH release but through distinct upstream signals.
Evidence
Both are preclinical-to-early-clinical compounds with no completed human outcome trials for any body-composition indication. Ipamorelin has some older phase-1 pharmacology. Neither has the human database that would justify confident therapeutic claims of any kind.
The stack claim
The "ipamorelin + CJC" pairing is justified in vendor copy as synergistic pulsatile GH stimulation — one short-acting GHRP pulse plus one longer GHRH signal. No controlled human trial has tested the combination. The rationale is at least pharmacologically coherent; the evidence for it is zero.
Selectivity claims
Ipamorelin is called "selective" because early animal work suggested less hunger and cortisol stimulation than older GHRPs. "Selective" here means relatively fewer off-target effects in rodents — not selective in any approved-medicine sense.
Safety and sport
Both are prohibited by WADA. Neither has a human safety database; the practical risks concentrate in unverified product identity and sterility, which no amount of mechanism talk can compensate for.
Frequently Asked Questions
Which is better for GH release?
There is no human comparative data that could answer this. Any confident ranking you encounter is marketing.
Why are they sold as a pair?
Because the pharmacological rationale sounds good and two products sell better than one. That is a commercial explanation, not a scientific one.
Are they safer than injected HGH?
"Not replacing GH with external GH" is a genuine mechanistic difference, but without human safety data or verified product, "safer" is a claim nobody can currently make.
Evidence tier: Clinical-stage · Last reviewed: 2026-09-05 · Sources cited below.