Pralmorelin, GHRP Kaken 100
Evidence Grade C — Moderate human evidence. 203 published studies, 131 human. 0 registered clinical trials.
GHRP-2 (pralmorelin) is a synthetic growth hormone secretagogue — a peptide that stimulates the pituitary gland to release growth hormone. It is used in Japan solely as a diagnostic tool to test whether the pituitary can respond to growth hormone stimulation. It has no therapeutic approval anywhere. It is prohibited by WADA in sport.
203 published studies: 131 human, 61 animal, 24 in-vitro, 17 reviews
GHRP-2 is approved in Japan exclusively as a diagnostic tool for growth hormone deficiency — not as a therapeutic agent. The diagnostic protocol involves a single 100 mcg intravenous injection with growth hormone measurement over 60 minutes. It has no therapeutic approval in any jurisdiction.
No therapeutic Phase III trials have been conducted. The compound's availability through unregulated channels for non-diagnostic purposes is not supported by clinical evidence. Its approval as a diagnostic in Japan should not be interpreted as therapeutic approval.
Research suggests GHRP-2 activates the ghrelin receptor on pituitary cells. Unlike ipamorelin, it also stimulates ACTH, cortisol, and prolactin release, indicating a less selective profile. Its diagnostic use in Japan relies on measuring the growth hormone response to a standardised intravenous dose to identify growth hormone deficiency.
Research suggests GHRP-2's diagnostic use in Japan is well established, involving a single intravenous injection with growth hormone measurement over 60 minutes. No therapeutic Phase III trials have been conducted for any condition. Unlike the more selective ipamorelin, GHRP-2 also stimulates cortisol, ACTH, and prolactin release, indicating a less targeted pharmacological profile. The diagnostic approval in Japan should not be interpreted as therapeutic approval. Products from unregulated channels lack pharmaceutical quality assurance.
No trials registered on ClinicalTrials.gov for this compound.
The information on this page is provided for educational and research reference purposes only. This is not medical advice. Always consult a qualified healthcare professional before making any health-related decisions.
Somatropin has been available since the mid-1980s and is one of the most established peptide therapies. It is sold under numerous brand names including Genotropin, Humatrope, Norditropin, and Omnitrope (the first biosimilar approved in the US, 2006). Approved indications include childhood and adult growth hormone deficiency, Turner syndrome, children born small for gestational age, Prader-Willi syndrome, idiopathic short stature, and short stature from chronic kidney disease. Daily injection has been the main burden of somatropin therapy, particularly for paediatric patients who may require years of treatment. This has driven the development of once-weekly alternatives (somatrogon and somapacitan), which are gradually changing the treatment landscape. Annual treatment costs remain substantial, and concerns about misuse in anti-ageing and performance enhancement contexts are ongoing.
Tesamorelin is marketed as Egrifta SV (approved November 2010) for the reduction of excess abdominal fat in HIV-infected patients with lipodystrophy. In clinical trials, it reduced visceral fat by approximately 15% compared to a 5% increase with placebo, and this reduction was sustained with continued treatment. Tesamorelin occupies a unique niche — it is the only approved GHRH analogue and the only medication specifically approved for HIV-associated lipodystrophy. Beyond its approved indication, it has attracted research interest for potential effects on liver fat, cognitive function, and peripheral neuropathy. Fat reduction reverses when treatment stops, and it is not approved for general weight loss or body composition purposes.
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