# CJC-1295 Ipamorelin and Mod GRF (1-29), the No-DAC Form

> CJC-1295 Ipamorelin and Mod GRF (1-29), the no-DAC form: a short, pulsatile GHRH signal lasting about 30 minutes, why it differs from the DAC version, and what is studied. Cited.

The short, pulsatile GHRH signal — what it is, how it differs from the DAC version, and where the data actually stop.

## The short version

In CJC-1295 Ipamorelin, "Mod GRF (1-29)" is just the no-DAC form of the CJC-1295 half — and the source of a lot of name confusion. Mod GRF (1-29) is a modified 29-amino-acid fragment of GHRH (the brain's natural "make growth hormone" signal). It does the same job as the DAC version — switch on the GHRH receptor on the pituitary — but without the albumin-binding tag, so it lasts only about thirty minutes instead of days. Think of it as a quick tap on the GH switch rather than a long press. The idea behind pairing the short form with ipamorelin is to recreate the body's own brief, simultaneous bursts of GH more faithfully than a multi-day signal would. Like every part of this stack, it is a research chemical, not an approved drug, and the human data on it are thin.

## What Mod GRF (1-29) actually is

Mod GRF (1-29) — "modified GRF(1-29)" — is CJC-1295 without the Drug Affinity Complex. It keeps the DPP-IV-resistant amino-acid substitutions that protect the peptide from the enzyme that rapidly clips native GHRH [11], but it omits the C-terminal maleimidopropionamide-lysine that the DAC form uses to bond serum albumin. The result is a peptide that activates the same GHRH receptor on pituitary somatotrophs, raising cAMP through the Gs pathway and prompting GH release — but with no albumin anchor to keep it in circulation. Its CAS identifier (446262-90-4) differs from the DAC form (863288-34-0), reflecting that they are chemically distinct molecules despite sharing a name and a target.

## The pharmacology: a short, pulsatile signal

Functionally, Mod GRF (1-29) behaves like native GHRH: a brief, pulsatile GH-releasing signal lasting on the order of thirty minutes, after which it is cleared. There is no formal standalone human pharmacokinetic study of the no-DAC form; what is known is read across from the GHRH-analogue literature and from CJC-1295's own engineering, where the DPP-IV-resistant modifications were specifically introduced because unmodified GHRH(1-29) has a plasma half-life under a few minutes [11]. The contrast with the DAC form is stark and well measured on the other side: the DAC version raises GH and IGF-1 for days from a single dose [1], whereas the no-DAC form's action is over in well under an hour.

## Why pair the no-DAC form with ipamorelin

The research-protocol rationale for using Mod GRF (1-29) rather than the DAC form alongside ipamorelin is timing. Ipamorelin produces a single short GH pulse cleared within hours [2]; a short GHRH pulse from the no-DAC form lines up with it, so both arms fire briefly and together. That more closely resembles the body's own coordinated GHRH-plus-ghrelin bursts — and it resembles the classic synergy experiments, which combined short, simultaneous GHRH and GH-releasing-peptide doses and saw supra-additive GH release [3]. A multi-day DAC background, by contrast, holds the GHRH arm on continuously, which is a different pattern than those experiments studied.

None of this makes the no-DAC pairing established or safe — it makes it a coherent design choice. There is still no controlled human trial of either pairing, and Mod GRF (1-29), like CJC-1295 and ipamorelin, is a research chemical, not FDA-approved, and WADA-prohibited for athletes under Section S2.

---

A darkroom field notebook on the CJC-1295 + ipamorelin pairing — each peptide developed against its own studies, the supra-additive growth-hormone pulse traced and cited, and the never-trialed blend left as the one honest unexposed plate; no clinic behind the safelight and nothing here dosed, compounded, prescribed, or sold.