Hormone Analogues

Modified C-terminal fragment of human growth hormone (hGH 177–191)

AOD-9604 is a modified 16-residue C-terminal fragment of human growth hormone (residues 177–191) with an added N-terminal tyrosine. It was developed in the late 1990s–early 2000s as a candidate anti-obesity compound. Published primary research is dominated by rodent and rabbit models. AOD-9604 is not approved as a medicine.

Preclinical (rodent and rabbit) literature; Phase II clinical interest in early 2000s, limited published trial results

Long-acting amylin analogue · Investigational

Cagrilintide is an acylated long-acting analogue of the pancreatic hormone amylin. It is investigational and is most often discussed in the literature alongside semaglutide as the CagriSema combination. The Lau 2021 Phase 2 dose-finding RCT established the monotherapy efficacy and safety profile in obesity.

Phase II clinical evidence published; ongoing Phase III development including the CagriSema (cagrilintide + semaglutide) combination

Synthetic GHRH analogue (with or without DAC)

CJC-1295 is a synthetic GHRH analogue investigated in early-phase human pharmacology studies and in GHRH-knockout rodent models. Published primary human research is limited to small Phase I/II pharmacokinetic and pharmacodynamic trials.

Phase I/II human pharmacology and rodent literature

Synthetic hexapeptide growth hormone secretagogue (GHRP); a.k.a. pralmorelin

GHRP-2 is a synthetic six-residue growth hormone-releasing peptide. As pralmorelin, it has been used in Japan as a diagnostic agent for growth hormone deficiency testing. Most peer-reviewed primary research consists of small human pharmacology studies and in vitro / animal mechanism work.

Diagnostic-context approved use in Japan (pralmorelin) for GH-deficiency testing; broader literature is preclinical and small-cohort pharmacology

First-generation synthetic hexapeptide growth hormone secretagogue (GHRP)

GHRP-6 is one of the original synthetic growth hormone-releasing peptides (Bowers and colleagues, 1980s). It established the GHRP class and remains a reference compound in receptor pharmacology. A substantial rodent literature has subsequently explored cytoprotective and organ-injury models.

Foundational early-phase pharmacology + sizeable rodent literature on cytoprotection and organ-failure models

Synthetic hexapeptide growth hormone secretagogue (GHRP)

Hexarelin is a synthetic six-residue growth hormone-releasing peptide (GHRP). It was developed in the 1990s and is referenced in early-phase human pharmacology studies (often comparing GH-releasing peptides) and a sizeable rodent literature, including cardiovascular and metabolic models. It is not approved as a medicine.

Mixed evidence: small early-phase human pharmacology studies + extensive rodent literature

Selective ghrelin / GHS-R1a receptor agonist (GHRP)

Ipamorelin is a synthetic pentapeptide ghrelin (GHS-R1a) receptor agonist developed at Novo Nordisk in the late 1990s as a selective growth hormone secretagogue. Published work includes early-phase human pharmacokinetic studies and a body of rodent preclinical literature. Ipamorelin is not approved as a medicine and is not for human use outside of regulated research settings.

Early-phase clinical pharmacokinetic research and preclinical animal literature

Dual GLP-1 / glucagon receptor agonist · Conditionally approved in China; investigational elsewhere

Mazdutide (IBI362, originally LY3305677) is a once-weekly dual GLP-1 / glucagon receptor agonist. Originally developed by Eli Lilly and now advanced by Innovent Biologics, mazdutide is most extensively studied in Chinese populations. It has received conditional approval in China for chronic weight management; international regulatory approvals are not yet in place at the time of writing.

Phase III evidence published in Chinese adults with obesity; conditionally approved in China for chronic weight management

Endogenous nonapeptide hormone · FDA-approved (Pitocin) for labour induction and postpartum uterine atony

Oxytocin is an endogenous nine-residue cyclic peptide hormone synthesised in the hypothalamus. It is FDA-approved (Pitocin) for labour induction and management of postpartum uterine atony. Intranasal oxytocin is an active research area in psychiatric and behavioural-neuroscience contexts, though those uses remain investigational.

Decades of obstetric clinical use; active intranasal-pharmacology research in psychiatric and social-behaviour contexts

Triple GIP / GLP-1 / glucagon receptor agonist · Investigational (Phase III ongoing)

Retatrutide (LY3437943) is a single peptide engineered to act at three incretin and metabolic receptors — GIP, GLP-1, and glucagon. It is investigational and not approved as a medicine at the time of writing. Phase II data have been published for obesity and type 2 diabetes; Phase III trials are ongoing.

Phase II clinical evidence published; Phase III TRIUMPH and TRIUMPH-OUTCOMES programmes ongoing

GLP-1 receptor agonist · FDA-approved (Ozempic / Wegovy / Rybelsus)

Semaglutide is an acylated GLP-1 analogue with a long-chain fatty diacid side chain that extends its half-life via tight albumin binding, enabling once-weekly dosing. It is FDA-approved as Ozempic and Rybelsus (oral) for type 2 diabetes mellitus and as Wegovy for chronic weight management. The STEP programme provides the primary weight-management evidence and the SUSTAIN and SELECT programmes cover diabetes and cardiovascular outcomes.

Phase III clinical evidence; FDA-approved for type 2 diabetes (Ozempic / Rybelsus) and chronic weight management (Wegovy)

Synthetic GHRH(1–29) analogue · Historically FDA-approved (Geref; discontinued 2008)

Sermorelin is the C-terminally amidated 29-residue N-terminal fragment of human GHRH. It was FDA-approved as Geref for paediatric growth hormone deficiency in the late 1990s; the originator product was discontinued from US distribution in 2008 and the compound is no longer marketed by the original sponsor. Research literature includes paediatric clinical trials, PEGylated analogue development, and anti-doping detection methodology.

Historical clinical use (paediatric GH deficiency); current research includes preclinical analogue and detection methodology

Dual GLP-1 / glucagon receptor agonist · Investigational (Phase III ongoing)

Survodutide (BI 456906) is a once-weekly dual agonist at GLP-1 and glucagon receptors developed by Boehringer Ingelheim. Phase II evidence has been published in adults with obesity and in adults with MASH (metabolic dysfunction-associated steatohepatitis). It is investigational — not FDA-approved at the time of writing.

Phase II clinical evidence published in obesity and metabolic dysfunction-associated steatohepatitis (MASH); Phase III development underway

Synthetic GHRH(1–44) analogue · FDA-approved (Egrifta)

Tesamorelin is a synthetic 44-residue analogue of human GHRH (with an N-terminal trans-3-hexenoyl modification for stability). It is FDA-approved as Egrifta / Egrifta SV for the reduction of excess abdominal fat in patients with HIV-associated lipodystrophy. Approval is indication-specific; use outside that indication is investigational.

Phase III clinical evidence; FDA-approved for HIV-associated lipodystrophy

Dual GIP / GLP-1 receptor agonist · FDA-approved (Mounjaro / Zepbound)

Tirzepatide is a lipidated synthetic peptide that activates both the GIP and GLP-1 receptors. It is FDA-approved as Mounjaro for type 2 diabetes mellitus and as Zepbound for chronic weight management in adults with obesity or overweight with at least one weight-related condition. The SURPASS (T2D) and SURMOUNT (obesity) Phase III trial programmes provide the primary efficacy and safety evidence base.

Phase III clinical evidence; FDA-approved for type 2 diabetes (Mounjaro) and chronic weight management (Zepbound)