If you have been reading about DAC and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-03-22. Numbers and descriptions here follow the published literature rather than marketing material.
CJC-1295 belongs to a class of synthetic peptides modeled on growth hormone releasing hormone, a forty-four amino acid signal produced by the hypothalamus. The compound is built from the first twenty-nine residues of the natural sequence, with four substitutions introduced at positions 2, 8, 15 and 27. These changes were designed to slow enzymatic breakdown while preserving receptor activation. The result is a peptide that is shorter than native GHRH and considerably more resistant to ordinary clearance pathways in circulation.
Two related forms appear under the CJC-1295 name. The simpler analogue, commonly written as modified GRF(1-29), carries the four substitutions but no additional conjugation. The second form attaches a maleimidopropionic acid linker to a lysine residue, a modification frequently called the drug affinity complex. That linker reacts with the free thiol on serum albumin to form a covalent bond. Because albumin has a long residence time in blood, the conjugated peptide stays in circulation far longer than the unconjugated analogue.
Receptor level activity follows the canonical GHRH pathway. The peptide binds the GHRH receptor, a class B G protein coupled receptor on somatotroph cells of the anterior pituitary. Binding raises intracellular cyclic AMP, which promotes calcium entry and the release of growth hormone into the bloodstream. Because the molecule acts at the same receptor as the endogenous hormone, its effect is superimposed on the natural pulsatile rhythm rather than replacing it. Whether sustained receptor occupation leads to desensitization is not fully settled.
The distinguishing feature of the DAC form is a maleimide-containing group that reacts with the free thiol of cysteine-34 on human serum albumin. This reaction forms a covalent bond without enzymatic assistance, and it takes place after the peptide enters the bloodstream. Because albumin is abundant and long-lived, the attached peptide is carried through circulation far longer than an unmodified fragment would survive. The chemistry is a deliberate pharmacokinetic strategy rather than a change to receptor activity.
Enzymatic protection is a separate mechanism from plasma protein binding. The four substitutions in the backbone reduce recognition by dipeptidyl peptidase IV, which normally cleaves the natural hormone within minutes. Without the reactive group, this resistance still yields only a short window of activity, generally reported in the range of tens of minutes. With it, reported half-lives in early human work extended to several days. The size of that gap is the main practical distinction between the two materials.
Both forms act at the pituitary receptor for growth hormone-releasing hormone and increase growth hormone output, which in turn raises insulin-like growth factor 1. A long-acting analog produces sustained rather than pulsatile stimulation, and the physiological consequences of that pattern are not fully settled. Published human data on the extended form remain limited, and much of what circulates in discussion traces to early company reports rather than independent replication. How sustained exposure affects normal feedback remains an open question.
| Property | Value | Notes |
|---|---|---|
| Peptide class | Synthetic GHRH analogue | Built on a 29 residue sequence |
| Primary target | GHRH receptor (GHRHR) | Class B G protein coupled receptor |
| Unconjugated half life | Minutes | Limited by protease degradation |
| Key modification | Four residue substitutions | Positions 2, 8, 15 and 27 |
| Common synonym | Modified GRF(1-29) | Usually denotes the form without DAC |
CJC-1295 acts at the growth hormone-releasing hormone receptor, a G-protein-coupled receptor found on somatotroph cells in the anterior pituitary. Binding triggers a rise in cyclic AMP and calcium entry, which promotes release of stored growth hormone. Because the peptide mimics the body's own releasing hormone, it amplifies existing secretory pulses rather than driving continuous output. The size of the response therefore depends partly on the subject's own hormonal rhythm and feedback state.
The attached maleimide group explains the unusual duration of the DAC version. After injection it reacts with the thiol of cysteine-34 on serum albumin, forming a stable covalent bond. The resulting conjugate is too large for rapid kidney filtration and is shielded from many peptidases. Reported half-lives for this form reach several days, whereas the version without the group is cleared in roughly half an hour. That gap is the main pharmacological difference between the two.
CJC-1295 is a synthetic peptide belonging to the growth hormone-releasing hormone analog family. It comprises twenty-nine amino acid residues derived from the N-terminal region of natural GHRH. The molecule incorporates several non-natural substitutions that increase resistance to enzymatic degradation. These modifications extend its activity compared with the native hormone fragment. Researchers use it to study pituitary growth hormone secretion in laboratory and clinical settings. This compound is distinct from native GHRH in its stability profile.
Two principal forms appear in the literature and in research supply. One carries a drug affinity complex, a maleimide-based group that forms a covalent bond with circulating albumin. This linkage slows clearance and produces a long-lasting elevation of peptide levels. The other form lacks that group and is often labeled MOD GRF(1-29). It has a much shorter circulation time. Both variants retain the same core receptor-binding sequence. Reported half-lives differ substantially between the two.
== Business career == Newsom and a group of investors created the company PlumpJack Associates L.P. on May 14, 1991. The group started the PlumpJack Winery in 1992 with the financial help of his family friend Gordon Getty. PlumpJack was the name of an opera written by Getty, who invested in 10 of Newsom's 11 businesses. Getty told the San Francisco Chronicle that he treated Newsom like a son and invested in his first business venture because of that relationship. According to Getty, later business investments were because of "the success of the first". One of Newsom's early interactions with government occurred when Newsom resisted the San Francisco Department of Public Health's requirement to install a sink at his PlumpJack wine store. The Health Department argued that wine was a food and required the store to install a $2,700 sink in the carpeted wine shop on the grounds that the shop needed the sink for a mop. When Newsom was later appointed supervisor, he told the San Francisco Examiner: "That's the kind of bureaucratic malaise I'm going to be working through." The business grew to an enterprise with more than 700 employees. The PlumpJack Cafe Partners L.P. opened the PlumpJack Café, also on Fillmore Street, in 1993. Between 1993 and 2000, Newsom and his investors opened several other businesses that included the PlumpJack Squaw Valley Inn with a PlumpJack Café (1994), a winery in Napa Valley (1995), the Balboa Café Bar and Grill (1995), the PlumpJack Development Fund L.P.
=== Peptide Folding === Coupling ribosome profiling with ChIP can elucidate how and when newly synthesized proteins are folded. Using the footprints provided by Ribo-Seq, specific ribosomes associated with factors, like chaperones, can be purified. Pausing the ribosome at specific time points, allowing it to translate a polypeptide over time, and exposing the different points to a chaperone and precipitating out using ChIP purifies these samples and can show at which point in time the peptide is being folded.
=== Fourth representation === The fourth version of the thermospray vaporizer heats the capillary tube only by direct DC/AC ohmic (Joule) heating. A thermocouple placed in thermal contact with the exit of the capillary is used to prevent the destructive thermal runaway caused by overheating. This representation was concluded to be the ideal design by the 1988 patent.
Sources: en.wikipedia.org
== Mechanism of action == The sensitization of pronociceptive pathways in response to opioid treatment appears to involve several pathways. Research thus far has primarily implicated the μ-opioid receptors (MOR) abnormal activation of NMDA receptors in the central nervous system, and long-term potentiation of synapses between nociceptive C fibers and neurons in the spinal dorsal horn.
=== Pharmacokinetics === Migalastat is almost completely absorbed from the gut; taking the drug together with food decreases its absorption by about 40%. Total bioavailability is about 75% when taken without food. The substance is not bound to blood plasma proteins. Only a small fraction of a migalastat dose is metabolized, mainly to three dehydrogenated O-glucuronides (4% of the dose) and a number of unspecified metabolites (10%). The drug is mainly eliminated via the urine (77%) and to a smaller extent via the faeces (20%). Practically all of the metabolites are excreted in the urine. Elimination half-life is three to five hours after a single dose.
== External links == whatisbifidusregularis.org/ – A deconstruction of the terms Bifidus Actiregularis, Bifidus Regularis, Bifidus Digestivum, L. Casei Immunitas and their variants, as well as the marketing strategy, and information about the potential health benefits of live yoghurts. Food-Info.net – How to select a probiotic Type strain of Bifidobacterium animalis at BacDive – the Bacterial Diversity Metadatabase
Sources: en.wikipedia.org
The names are often used interchangeably in casual writing, but they are not strictly identical. Modified GRF(1-29) refers to the unconjugated analogue carrying only the four substitutions. The version sold as CJC-1295 with DAC includes the albumin binding linker and clears much more slowly.
DAC stands for drug affinity complex, a term describing the maleimidopropionic acid linker. This group forms a covalent bond with the cysteine residue on serum albumin after administration. The resulting adduct is what extends the circulating half life from minutes to days.
No. It is entirely synthetic and does not correspond to any known endogenous peptide. The design starts from human growth hormone releasing hormone and introduces deliberate substitutions. Any biological effect comes from mimicking the natural hormone at its receptor.
A maleimide moiety reacts with the thiol of cysteine-34, forming a covalent bond. The reaction occurs in circulation without enzymatic catalysis.