CJC-1295 vs Ipamorelin: Two Growth Hormone Peptides Compared

How we built this table

The identity, regulatory, anti-doping, study-count and supplier rows come from our substance records. The editorial rows were compiled from the published studies that first described each peptide, the human trials that followed, ClinicalTrials.gov records, a 2026 review and FDA documents, all checked on October 25, 2026. The comparison is informational. It is not a ranking, and it does not suggest that either substance is suitable for personal use.

Different molecules, different receptors

CJC-1295 is a modified version of the first 29 amino acids of growth hormone-releasing hormone (GHRH), the body's own signal for releasing growth hormone. In the paper that first described it, four amino acids are substituted and a reactive group is added that attaches to albumin in the blood. The authors tested it in rat pituitary cells and in rats, where it was still present in plasma beyond 72 hours and produced a larger growth hormone response than the unmodified 29-amino-acid peptide ^{Source [1]}.

Ipamorelin is a five-amino-acid peptide that includes amino acids not found in natural proteins ^{Source [4]}. It releases growth hormone through a different receptor, described in its first paper as the receptor for growth hormone-releasing peptides (GHRPs). Its first published study tested it in rat pituitary cells, rats and pigs. In rats and pigs it released growth hormone about as strongly as the older compound GHRP-6, and in pigs it did so without the rises in the stress hormones ACTH and cortisol seen with GHRP-6 and GHRP-2 ^{Source [2]}. Later papers describe it as a ghrelin mimetic ^{Source [8] Source [9]}.

Which molecule is meant

The name CJC-1295 is used for two different things. A 2026 review notes that the human trials tested the albumin-binding version, often sold as "with DAC", and states that no controlled clinical studies have evaluated the version without it, which is sold as "Mod GRF 1-29" ^{Source [3]}. Ipamorelin has a quieter version of the same problem: when FDA reviewed it for pharmacy compounding in 2024, the names, registry numbers and lab reports in the nominations did not agree on whether the free base or the acetate salt was meant, so FDA evaluated both ^{Source [4]}.

What was measured in people

For CJC-1295, two randomized, placebo-controlled, double-blind trials in healthy adults aged 21 to 61 found dose-dependent rises in growth hormone and IGF-1, with IGF-1 staying elevated for more than a week after a single injection and no serious adverse reactions reported ^{Source [5]}. A follow-up study in healthy young men, without a placebo group, found that normal pulses of growth hormone release were preserved while baseline levels rose ^{Source [6]}. These studies measured hormone levels, not body composition, strength, recovery or aging. A phase 2 trial in people with HIV-associated abdominal fat is listed as terminated, with a completion date of September 2006, and has posted no results ^{Source [11]}.

For ipamorelin, a dose-escalation study in healthy men found that each infusion produced a single, short episode of growth hormone release, and ipamorelin itself had a half-life of about two hours ^{Source [7]}. Its clinical development targeted gut recovery after abdominal surgery. In rats, it shortened the time to the first bowel movement after surgery ^{Source [8]}. In people, a randomized, placebo-controlled phase 2 trial after bowel resection (117 enrolled, 114 analyzed) found it well tolerated but found no significant differences from placebo in the key or secondary efficacy analyses ^{Source [9] Source [10]}. A larger phase 2 trial with 320 participants was completed in 2014 and has posted no results ^{Source [12]}.

The pairing

In a PubMed search on October 25, 2026, we found no trial, case report or other human study that gave CJC-1295 and ipamorelin together; the matching records were mostly reviews, plus two laboratory analyses ^{Source [13]}. The 2026 review says the pairing, usually with the version without DAC, is driven largely by anecdote, and that long-term safety data are lacking for these peptides ^{Source [3]}. A combination that has not been tested cannot borrow evidence from its parts; our guide on how to read a peptide study explains why.

Safety signals FDA has described

FDA's compounding safety page says it has identified serious adverse events associated with CJC-1295, including increased heart rate, and that clinical data are limited. For ipamorelin acetate, it cites a published study of intravenous ipamorelin for gastric motility that reported serious adverse events, including death. At FDA's 2024 advisory committee meeting, staff said the two deaths in ipamorelin-treated patients in the published bowel-surgery trial occurred after therapy ended and that it was unclear whether they were related to ipamorelin ^{Source [4]}. For both, it says compounded products may pose a risk of immune reactions by certain routes ^{Source [14]}.

What the table does not show

The table does not show that either peptide improves any health outcome, and it does not describe products sold outside trials. For the full research profile of each molecule, see CJC-1295 and ipamorelin: reading the research separately. We do not give dosing, preparation or usage guidance, and research listings are not for personal use.