This area studies compounds that act on the gut and metabolic hormone systems — most famously the GLP-1 family (semaglutide, tirzepatide, retatrutide). In the research literature they are examined for effects on appetite, blood sugar, and body weight. A few, like semaglutide and tirzepatide, also exist as FDA-approved prescription medicines under brand names; the versions sold to laboratories are research chemicals, not the approved drugs.
This is the one area on the site where the science is genuinely strong for some compounds. The GLP-1 class drugs semaglutide (sold as Wegovy/Ozempic) and the GLP-1/GIP drug tirzepatide (Zepbound/Mounjaro) have been through large, multi-year randomized human trials and are FDA-approved brand medicines. In those trials semaglutide produced roughly 12-15% average body-weight reduction and tirzepatide around 18-21%, versus a few percent on placebo. Gastrointestinal side effects (nausea, vomiting, diarrhea) were common. Those are real, well-documented results for the approved drugs.
Retatrutide and cagrilintide are investigational. Retatrutide (a triple-hormone agonist) has published phase 2 human data showing large weight reductions, but it is not yet FDA-approved and phase 3 testing is ongoing. Cagrilintide (an amylin analogue) also has phase 2 human data, mostly studied alongside semaglutide. These are promising but unfinished stories.
AOD-9604 and HGH Fragment 176-191 are the weakest of the group. AOD-9604 is a fragment of growth hormone that showed a small early weight-loss signal, but its development was terminated after a larger 24-week human trial failed to beat placebo. HGH Fragment 176-191 has essentially no quality human weight-loss trials and rests on animal/lab work. Importantly, none of these are the same thing as the FDA-approved brand drugs — the research-chemical versions sold to labs have not been through that testing or manufacturing oversight.
Sources: GLP-1 receptor agonists for obesity — systematic review (NCBI PMC) · Retatrutide for Obesity — Phase 2 Trial (NEJM) · Once-weekly cagrilintide for weight management — Phase 2 trial (PubMed) · AOD-9604 development history (Wikipedia, secondary summary) · How we source this ›
Each links to a full profile — identity, what it is, regulatory status, storage, and cited sources. Everything is framed for research use only; none of this is a recommendation to take anything.
AOD-9604 is a synthetic modified fragment of the C-terminal region of human growth hormone with an added N-terminal tyrosine.
Cagrilintide is a long-acting synthetic analog of the hormone amylin, being developed by a pharmaceutical company as an investigational drug.
HGH Fragment 176-191 is a synthetic peptide corresponding to the C-terminal region of human growth hormone.
Mazdutide (IBI362 / LY3305677) is a GLP-1 receptor and glucagon receptor dual agonist and oxyntomodulin analog developed by Innovent Biologics under license from Eli Lilly.
Retatrutide (Eli Lilly research code LY3437943) is an investigational peptide that acts on three gut/metabolic hormone receptors (GIP, GLP-1 and glucagon).
Semaglutide is a modified peptide that activates the GLP-1 gut-hormone receptor.
Survodutide (BI 456906) is a synthetic dual agonist of the glucagon receptor and the GLP-1 receptor, developed by Boehringer Ingelheim and Zealand Pharma and conceptually based on the gut hormone oxyntomodulin.
Tirzepatide is a modified peptide that activates two gut-hormone receptors (GIP and GLP-1).
Blend — 10 mg Retatrutide + 5 mg Cagrilintide
Blend — 5 mg Semaglutide + 5 mg Cagrilintide
Our rankings are never for sale, and we make no health or dosing claims. Research compounds are for laboratory use only.