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.
Sermorelin Acetate
A synthetic fragment of growth hormone releasing hormone that was formerly FDA-approved for diagnostic use and pediatric GH deficiency. The original product was withdrawn from the market, though compounded and research versions circulate.
What each molecule is
Sermorelin is the biologically active 1-29 fragment of human GHRH — a faithful copy of the natural signal. "CJC-1295" actually names two different molecules: Mod GRF 1-29 (sometimes called CJC-1295 without DAC) is a modified sermorelin analog, while CJC-1295 with DAC adds a lysine linker that extends half-life dramatically. Buyers frequently cannot tell which they have.
Evidence
Sermorelin has real human pharmacology behind it — decades-old studies on GH stimulation and pediatric diagnostic use, plus a withdrawal history that is itself informative. CJC-1295 has phase-1/2 pharmacokinetic data and a reported serious adverse event in early development that ended the program’s sponsor interest; it never reached registrational trials.
Half-life and dosing logic
Native GHRH and sermorelin act for minutes to hours, requiring frequent administration to mimic pulsatile GH release. CJC-1295 with DAC lasts days, which breaks the pulsatility argument entirely — GH stimulation becomes semi-continuous, a pattern the natural system avoids.
Safety
Sermorelin’s known profile comes from supervised clinical use. CJC-1295’s human safety record is thin, and the DAC version’s prolonged exposure raises questions no completed study has answered. Both are on WADA’s prohibited list.
The honest summary
One is a withdrawn medicine with a characterized past; the other is a research compound that never became one. Neither belongs in self-administration, and neither gray-market version carries any verified identity.
Frequently Asked Questions
Is CJC-1295 just long-acting sermorelin?
Mod GRF 1-29 is close to that description; CJC-1295 with DAC is pharmacologically a different proposition because its multi-day half-life abolishes the pulsatile pattern the whole GHRH concept depends on.
Why was sermorelin withdrawn?
Commercial reasons — not safety — drove the original withdrawal, but withdrawal still means no current approved product and no pharmacovigilance.
Do either raise GH like injections of HGH?
They stimulate natural GH release rather than replacing it — a real mechanistic distinction, but not a safety endorsement, since the stimulation itself is unmonitored in non-clinical use.
Evidence tier: Minimal evidence · Last reviewed: 2026-09-05 · Sources cited below.