CJC 1295

CJC 1295 is a synthetic peptide derived from growth hormone-releasing hormone (GHRH). It consists of 30 amino acids and was designed to increase the stability and duration of GHRH activity by binding to albumin and extending its half-life.

CJC 1295 is purported to promote muscle growth, reduce body fat, and improve recovery by increasing growth hormone and insulin-like growth factor 1 (IGF-1) levels. It is also believed to support better sleep and overall physical performance.

Clinical studies indicate that CJC‑1295 significantly raises levels of Growth Hormone (GH) and Insulin‑like Growth Factor‑1 (IGF-1) in healthy adults. One study reported 2- to 10-fold increases in GH for six days or more and 1.5- to 3-fold increases in IGF-1 for nine to eleven days following a single dose ¹. Another trial showed that trough (basal) GH levels increased roughly 7.5-fold, mean GH levels rose 46 %, and IGF-1 rose about 45 % one week post-injection, while preserving normal GH pulsatility ².

These hormonal changes are often interpreted as beneficial for muscle growth and fat loss. Because GH and IGF-1 are involved in protein synthesis and metabolic regulation, higher levels may support lean muscle mass and reduced body fat. The sustained elevation of GH/IGF-1 after CJC-1295 suggests it may assist in improving body composition and physical recovery. Overall, CJC‑1295 shows potential for enhancing anabolic and metabolic effects in adults through prolonged GH and IGF-1 elevation.

In human clinical studies, CJC 1295 was generally well tolerated, and most reported side effects were mild and temporary. The most common reactions included injection-site redness, pain, and swelling, which typically resolved without treatment ³. Some participants also experienced transient headaches and mild flu-like symptoms.

However, no serious or long-term adverse effects were reported in these studies, and laboratory findings did not show evidence of toxicity or organ dysfunction. Follow-up data indicated that hormone levels returned to baseline without persistent abnormalities after treatment cessation.

CJC‑1295 is a synthetic analogue of Growth Hormone–Releasing Hormone (GHRH) that binds to GHRH receptors on pituitary somatotroph cells to stimulate release of Growth Hormone (GH) and subsequent increase in Insulin‑like Growth Factor 1 (IGF-1). Clinical trials in healthy adults showed that a single injection increased plasma GH by approximately 2- to 10-fold for six or more days, and IGF-1 by about 1.5- to 3-fold for nine to eleven days, with continued elevation of IGF-1 after multiple doses for up to 28 days ⁴. The extended half-life (roughly 5.8-8.1 days) is achieved by adding a “Drug Affinity Complex” (DAC) to the peptide, which allows it to bind to serum albumin and resist rapid degradation. Animal studies using GHRH-knockout mice demonstrated that CJC-1295 normalized growth, increased GH-mRNA and pituitary somatotroph proliferation, showing that its mechanism involves sustained activation of the GH/IGF-1 axis ⁵.

As a bulk drug substance for compounding under the FDA’s interim 503A bulks list (“Category 2”) mechanisms, CJC‑1295 was previously nominated for inclusion, but the nominations were withdrawn and the FDA proposed that CJC‑1295 related bulk drug substances not be included on the 503A Bulks List ⁶. In Sport, the World Anti‑Doping Agency (WADA) includes GH‑releasing hormone analogues and related substances (e.g., CJC‑1295) under the category S2 ⁷.