CJC-1295 No DAC (Mod GRF 1-29): A Research Overview

CJC-1295 comes in two forms, and the difference between them is not a detail — it is the entire reason this version exists. The “no DAC” form, also more precisely called Modified GRF (1-29), is short-acting: it produces a brief, pulse-like burst of growth hormone release rather than the sustained, days-long elevation seen with the DAC version. That single property — pulsatility — shapes how it is studied, why it is paired with other peptides, and how it differs from its long-acting counterpart.

This overview summarizes what the published literature reports on CJC-1295 without DAC — its structure and naming, mechanism, evidence base, and regulatory status. It describes findings as they appeared in their study systems. It is not dosing guidance, medical advice, or a recommendation for use.

What CJC-1295 No DAC Is — and the Naming

CJC-1295 without DAC is a synthetic analog of growth hormone-releasing hormone (GHRH). Its more accurate name is Modified GRF (1-29), often written Mod GRF 1-29. The lineage is worth following: native GHRH has 44 amino acids; a truncated 29-amino-acid version (GRF 1-29, also known as sermorelin) retains the active region; and Mod GRF 1-29 takes that backbone and adds four amino-acid substitutions that resist enzymatic degradation and improve receptor binding (Mod GRF 1-29 structure and lineage).

There is a genuine technical nuance here that many descriptions get wrong, and stating it correctly is part of an accurate overview. Mod GRF 1-29 corresponds to the portion of CJC-1295 (DAC) that is not bound to the Drug Affinity Complex, minus a lysine residue. A literal “CJC-1295 without DAC” that still retained that lysine but lacked the affinity complex would not behave like Mod GRF 1-29 — it would be a different and less stable molecule (naming/structure clarification). In practice, “CJC-1295 no DAC” and “Mod GRF 1-29” are used interchangeably to mean the short-acting tetrasubstituted GHRH analog.

Mechanism — Pulsatile, Not Continuous

Like all GHRH analogs, Mod GRF 1-29 binds the GHRH receptor on pituitary somatotroph cells, activating the cAMP pathway and stimulating synthesis and release of growth hormone, which in turn drives hepatic IGF-1 production (mechanism of action, BOC Sciences). What distinguishes it from the DAC version is duration. Without the albumin-binding complex, its half-life is roughly 30 minutes, so it produces a short, sharp pulse of GH release that more closely resembles the body’s own episodic secretion pattern.

That pulsatility is the whole point. Growth hormone is naturally secreted in pulses, not as a flat continuous signal, and one rationale offered for the short-acting form is that preserving this rhythm may reduce the receptor desensitization that prolonged, continuous stimulation could theoretically cause. While the DAC version is studied as a model of sustained GHRH-axis activation, the no-DAC version is studied as a model of timed, pulse-like stimulation — two distinct research tools derived from closely related molecules.

This is also why, in both research and community discussion, the no-DAC form is typically paired with ipamorelin: a short GHRH pulse from Mod GRF 1-29, combined with a ghrelin receptor agonist, is used to model a more physiological combined GH response. That pairing is covered separately in the CJC-1295 and ipamorelin combination overview.

The Evidence Base

The human pharmacology of CJC-1295 largely traces back to early work on the DAC version — most notably the Teichman et al. dose-escalation study, which reported dose-dependent increases in GH and IGF-1 and was described as relatively well tolerated in healthy adults (Teichman et al., J Clin Endocrinol Metab 2006). For the short-acting no-DAC form specifically, the evidence is thinner and leans on its shared GHRH-analog mechanism, the established pharmacology of sermorelin (its close structural relative), and preclinical and community-protocol data rather than dedicated large human trials.

The honest characterization: the mechanism is well understood, and the GHRH-analog class has real clinical grounding, but there is no large, controlled human trial program for Mod GRF 1-29 as a standalone agent establishing efficacy or long-term safety. Mechanistic plausibility and a credible class are not the same as confirmed standalone clinical evidence.

• The molecule’s mechanism is well characterized; dedicated standalone human efficacy trials are lacking.
• Much of the cited human pharmacology comes from the DAC version and from sermorelin, not from Mod GRF 1-29 itself.
• Pulsatile dosing is a theoretical advantage over continuous stimulation, not a demonstrated clinical-outcome difference.

Regulatory and Anti-Doping Status

The status below reflects mid-2026 and is in flux; verify against current FDA notices before relying on it. CJC-1295 (in any form, including no-DAC / Mod GRF 1-29) is not FDA-approved for any indication and is not a component of an approved drug. Its compounding status has been unsettled — caught up in the FDA’s evolving 503A peptide review — and any reclassification permitting compounding would still not constitute FDA approval. The World Anti-Doping Agency prohibits CJC-1295 for athletes (Category S2, peptide hormones and growth factors). Research-grade material is sold for laboratory use only and, by its labeling, is not for human consumption.

The fuller regulatory and safety history — including the discontinuation of CJC-1295’s clinical development after a trial death (attributed by the attending physician to pre-existing cardiovascular disease) — applies to the compound as a whole and is covered in the CJC-1295 with DAC overview. One safety contrast is worth noting in the no-DAC form’s favor: because its half-life is short, its effects clear quickly, so it does not carry the “cannot be reversed by stopping” concern intrinsic to the long-acting DAC version.

Why CJC-1295 No DAC Draws Research Interest

The appeal is precision. Mod GRF 1-29 offers a short, clean GHRH pulse that researchers can time and combine, making it a tool for studying pulsatile GH dynamics specifically, distinct from the sustained-stimulation model provided by the DAC version. The accurate framing is that it is a well-characterized, short-acting GHRH analog with a sound mechanism and a credible class behind it, but without dedicated large human trials, FDA approval, or a clear anti-doping prohibition. It is a useful research tool, studied for what its pulsatility reveals, not an approved therapy.

For deeper reading, the primary literature cited here is the best starting point, and the companion articles on the DAC version and the ipamorelin combination complete the picture. Related growth hormone secretagogue topics are collected in our peptide research library.