The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration

Dominikowski A, Rękoś Z, Olejarz M, Szczepanek-Parulska E, Domin R, Ruchała M · Frontiers in Endocrinology

Grades the human evidence into four tiers: tesamorelin alone has randomised trials within an approved indication; sermorelin, CJC-1295 with DAC and the ghrelin-receptor peptides have phase 1 or 2 studies that measure no body-composition or performance endpoint; CJC-1295 without DAC, PEG-MGF and IGF-1 LR3 have no peer-reviewed human study at all. For CJC-1295 with DAC it reports single injections raising growth hormone 2- to 10-fold for six days or more and IGF-1 1.5- to 3-fold for 9 to 11 days in healthy adults. For AOD9604 it states that the 24-week obesity trial of 502 randomised patients failed its primary weight endpoint, that this rests on sponsor-reported outcomes rather than a peer-reviewed efficacy paper, and that the osteoarthritis claims rest on the rabbit model with no human trial. Ipamorelin's one randomised human trial, in postoperative ileus, was negative. Both CJC-1295 and AOD9604 sit on the FDA's category 2 list of bulk substances for compounding.

Population

Narrative review from Poznań University of Medical Sciences of GHRH analogues (sermorelin, tesamorelin, CJC-1295), the GH fragment AOD9604, ghrelin-receptor peptides (GHRP-6, GHRP-2, hexarelin, ipamorelin) and IGF-1 analogues, with a mapping of unregulated dosing protocols

Intervention

n/a

Comparator

n/a

Limitations

A narrative review with a stated search strategy but no risk-of-bias appraisal, whose authors declare that generative AI tools assisted with language editing and initial literature screening; the article-processing charge was partly paid by the university's foundation and no other funding is declared. Its endpoints are body composition and endocrine safety, not joints.