AOD-9604 vs Semaglutide at a glance
| Property | AOD-9604 | Semaglutide |
|---|---|---|
| Structure | 16-amino-acid fragment of human growth hormone, Tyr-hGH(177-191) | 31-amino-acid GLP-1 analog with a fatty diacid chain for extended half-life |
| Origin | Monash University research, developed by Metabolic Pharmaceuticals, 1990s | Novo Nordisk, engineered from native human GLP-1 |
| Mechanism studied | Beta-3 adrenergic receptor mediated lipolysis, independent of the GH receptor | GLP-1 receptor agonism, glucose-dependent insulin release, appetite suppression |
| Largest human trial | 502-subject Phase 2b trial (METAOD006), 24 weeks | 1,961-subject Phase 3 trial (STEP 1), 68 weeks |
| Primary endpoint result | Did not separate from placebo on weight loss at any dose | 14.9% mean weight loss versus 2.4% on placebo |
| Cardiovascular outcome data | None | 17,604-patient trial (SELECT) showed reduced cardiovascular events |
| Approved drug product | None; obesity program discontinued in 2007 | Ozempic and Wegovy, both FDA approved |
A growth hormone fragment against a GLP-1 mimetic
AOD-9604 and semaglutide were built to solve the same problem from opposite directions. AOD-9604 takes the C-terminal 16 amino acids of human growth hormone, the segment researchers at Monash University identified as the fragment responsible for the hormone's fat-burning activity without its growth-promoting effects. The idea was to isolate lipolysis from the receptor pathway that drives IGF-1 release, cell proliferation, and the metabolic side effects that make long-term growth hormone treatment risky.
Semaglutide starts from a completely different hormone system. It is a modified version of glucagon-like peptide-1, a gut hormone that signals fullness to the brain and slows gastric emptying after a meal. Novo Nordisk extended its natural half-life from minutes to about a week by attaching a fatty acid chain that binds serum albumin, turning a hormone the body clears almost immediately into a once-weekly injection. The two compounds do not compete for the same receptor, act on different tissues, and came out of unrelated research programs roughly two decades apart.
What the trial evidence shows for AOD-9604
The animal data for AOD-9604 is consistent and dates back to 2000. A study using genetically obese rats found that daily treatment with the synthetic lipolytic fragment cut cumulative body weight gain by more than half compared to untreated controls, with a corresponding rise in lipolytic activity in adipose tissue (Ng et al., Hormone Research, 2000). A follow-up study in obese mice compared AOD-9604 directly against intact human growth hormone and found both increased fat oxidation and reduced weight gain, but only AOD-9604 did so without disturbing insulin secretion or glucose handling (Heffernan et al., International Journal of Obesity, 2001).
The human program ran to six randomized, placebo-controlled trials between 2001 and 2006, covering roughly 900 subjects across intravenous dosing, oral dosing, and two long-term efficacy studies. Across all six, AOD-9604 showed no meaningful change in IGF-1 levels and no significant effect on oral glucose tolerance. There were no drug-related serious adverse events either, a safety profile the trial authors describe as indistinguishable from placebo (Stier, Vos, and Kenley, Journal of Endocrinology and Metabolism, 2013). The two efficacy trials in that program, a 300-subject 12-week study and a 502-subject 24-week study known as METAOD006 or the OPTIONS trial, tested weight loss directly.
Metabolic Pharmaceuticals discontinued the obesity development program once the larger trial failed to separate AOD-9604 from placebo, a result covered in more depth in the site's AOD-9604 research overview. AOD-9604 later received self-affirmed GRAS status for use as a food ingredient, but that designation covers safety for consumption, not efficacy for weight loss, and no jurisdiction has approved it as a medicine.
What the trial evidence shows for semaglutide
Semaglutide's efficacy record is built on a much larger and more recent set of randomized trials. STEP 1 enrolled 1,961 adults with overweight or obesity and randomized them 2:1 to once-weekly semaglutide or placebo. After 68 weeks, the semaglutide group had lost a mean 14.9% of body weight against 2.4% on placebo, and 86.4% of semaglutide recipients reached at least 5% weight loss compared to 31.5% on placebo (Wilding et al., New England Journal of Medicine, 2021, n=1,961).
A separate trial then tested whether that weight loss changed cardiovascular risk directly. The SELECT trial followed 17,604 adults with established cardiovascular disease and obesity, without a diabetes diagnosis, for close to 40 months. Semaglutide lowered the combined rate of cardiovascular death, nonfatal heart attack, or nonfatal stroke to 6.5% versus 8.0% on placebo, a hazard ratio of 0.80 (Lincoff et al., New England Journal of Medicine, 2023, n=17,604). No comparable outcomes trial exists for AOD-9604, because its own efficacy program ended before reaching that stage.
The durability question complicates the picture for semaglutide. A STEP 1 extension study followed 327 of the original participants after treatment stopped and found they regained a mean 11.6 percentage points of the body weight they had lost within a year, though they still held a net 5.6% reduction from baseline (Wilding et al., Diabetes, Obesity and Metabolism, 2022, n=327). The trial authors frame the finding as evidence that obesity requires ongoing treatment rather than a fixed course, which is a different problem than the one AOD-9604 ran into.
Semaglutide works while a patient takes it. AOD-9604 did not show it works at all.
A discontinued program against an approved drug
The regulatory gap between these two compounds is the clearest way to read the comparison. AOD-9604 accumulated a genuinely large safety database, close to 900 subjects across six trials, and came away with a clean tolerability record. What it did not produce was a statistically convincing weight-loss signal in its pivotal trial, and Metabolic Pharmaceuticals stopped pursuing it as a drug candidate once that result came in. The compound survives today as a research reagent and a self-affirmed GRAS food ingredient, categories that require far less evidence than a drug approval.
Semaglutide passed through the opposite sequence. The SUSTAIN program established its glycemic effects in type 2 diabetes, the STEP program confirmed weight loss in people without diabetes at a scale no obesity drug had reached before it, and SELECT extended the case to hard cardiovascular endpoints. The FDA approved semaglutide as Ozempic for diabetes and later as Wegovy for chronic weight management, and it now functions as the reference compound other GLP-1, GIP, and glucagon receptor agonists in development, including retatrutide, are measured against. Gastrointestinal side effects, mainly nausea and diarrhea, are semaglutide's main tolerability cost, and they run at a meaningfully higher rate than anything reported for AOD-9604.
Storage, sourcing, and research handling in Indonesia
Both compounds are supplied to laboratories as lyophilized powder, and both need refrigeration once reconstituted regardless of how different their mechanisms are. Bali and Jakarta's humidity accelerates degradation faster than the temperate lab conditions most of the underlying stability data was collected in, a point the lyophilized peptide storage guide covers for tropical climates. The reconstitution guide walks through bacteriostatic water technique for either peptide, and the dosing calculator handles the concentration and draw-volume math for a specific vial once a published mcg or mg/kg figure needs converting.
Under BPOM's framework for laboratory materials, both AOD-9604 and semaglutide are handled as research reagents rather than registered pharmaceuticals when supplied for research use. Semaglutide additionally exists as an approved prescription medicine in Indonesia under its own regulatory pathway, a status research-grade material does not carry and that has no bearing on how a laboratory sample is classified. For a full treatment of either compound on its own, see the AOD-9604 research overview and the semaglutide research overview.