CJC-1295 with DAC is a synthetic analog of GHRH, the hormone the hypothalamus uses to tell the pituitary to release growth hormone. The DAC part lets the peptide latch onto blood albumin, so instead of a few minutes it keeps working for about a week. This is a reference article written for a research context. It is not medical advice and does not describe use in humans outside published studies.
What CJC-1295 is and why it carries DAC
Native GHRH survives in blood for mere minutes: enzymes take it apart almost as soon as it is released. That is inconvenient for anyone studying the growth hormone axis, because the signal disappears faster than it can be measured. CJC-1295 was built as an answer to this problem. Its designers took the active 29-amino-acid fragment of GHRH and swapped four positions so the usual enzymatic cut sites no longer work.
The core idea hides in three letters. DAC, short for Drug Affinity Complex, is a chemical linker at the end of the peptide that forms a covalent bond with albumin, the most abundant protein in plasma. The peptide effectively rides on albumin as a carrier, and its half-life stretches to several days. The pharmacokinetic part of the clinical study by Teichman and colleagues (Journal of Clinical Endocrinology and Metabolism, 2006) put it at 5.8-8.1 days.
What the studies in healthy adults showed
The same two randomized placebo-controlled trials by Teichman produced the core dataset on this molecule. After a single subcutaneous injection, mean plasma growth hormone stayed 2-10 times above baseline for at least six days, while IGF-1, the main mediator of growth hormone action, rose 1.5-3 fold and remained elevated for 9-11 days. After several consecutive doses IGF-1 stayed above baseline for up to 28 days. In other words, one molecule turned an axis usually measured in hours into a week-scale process.
Pulsatility survives
The pituitary releases growth hormone in short pulses, and physiologists have long held that the rhythm of those pulses drives much of the hormone's effect. So a separate question mattered: would continuous stimulation by a GHRH analog erase that rhythm? Ionescu and Frohman (2006) tested it directly, sampling blood every 20 minutes over 12 overnight hours one week after a CJC-1295 injection in healthy men. Pulse frequency and amplitude did not change. What did change was the floor: trough levels between pulses rose 7.5-fold, mean growth hormone went up 46% and IGF-1 45%. The molecule raised the baseline without touching the waves.
DAC and no-DAC: two different molecules under one name
The research peptide market also carries "CJC-1295 without DAC", better known as mod GRF(1-29). The backbone is the same, but without the albumin anchor it acts for minutes and produces a short discrete pulse instead of a week-long plateau. Some research questions need the plateau, others need the clean pulse, and the two molecules must not be confused. Reference data on regimens from published work sit on separate pages: CJC-1295 with DAC and CJC-1295 no-DAC.
Why CJC-1295 gets paired with ipamorelin
These two peptides keep appearing together in research protocols, and the reason is receptor logic. CJC-1295 works through the GHRH receptor and sets how large the release can be. Ipamorelin enters through a different door, the ghrelin receptor GHS-R1a, where it triggers the release itself and eases off somatostatin, the system's brake. The two signals add up instead of duplicating each other. For the ghrelin branch of the class we have separate reviews of GHRP-6 and GHRP-2, the two paths are compared head to head in GHRP-6 vs CJC-1295 DAC, and the map of the whole class lives in the growth hormone secretagogue overview.
Where to find study dosing data
Doses and schedules in the clinical work depended on design and goal, so we do not retell them in the blog, let alone present them as instructions. The published data are collected on the reference page CJC-1295 with DAC: regimens from studies.
Purity, COA and lot verification
CJC-1295 comes with one purely analytical trap: on the label, the DAC and no-DAC versions differ by a word, while in the vial only mass spectrometry can tell them apart, because their molecular masses differ. A laboratory record therefore weighs more here than anything printed on a box. Longeva sends batch samples to independent third-party laboratories itself; batches are accompanied by certificates of analysis (COA) with HPLC purity and mass spectrometry identity confirmation, and we publish them in the open COA archive. The record for a specific lot can be reached from the CJC-1295 DAC product page.
Summary
The strength of CJC-1295 with DAC is duration: it shifts the growth hormone axis from short bursts to a week-long elevation without erasing physiological pulsatility. That property made it the typical long-acting GHRH analog in research catalogs and the usual partner for GHS-R agonists.
This article is informational. CJC-1295 is an experimental compound not approved as a medicine; the products mentioned are supplied strictly for laboratory research use and are not intended for human consumption. The full reference list with links is in the CJC-1295 with DAC monograph.
