What it is
AOD-9604 is a short synthetic peptide made from the tail end (the C-terminus) of human growth hormone. Researchers noticed that this region of the GH molecule carried much of its fat-burning activity, and built a 16 amino acid fragment to see whether they could keep that effect without the rest of what growth hormone does: raised IGF-1, insulin resistance and higher blood sugar.
It was developed as an obesity drug and taken into human trials, but it was never approved. It sits in the glp1 category on this site because people look at it for the same goal, fat loss, though it has nothing to do with the GLP-1 receptor.
How it works
In human trials AOD-9604 did not raise IGF-1, so whatever it does is not the classic GH to IGF-1 route. The proposed mechanism works through fat cells directly.
In the 2001 mouse study by Heffernan and colleagues, both human GH and AOD-9604 raised the expression of the beta-3 adrenergic receptor in fat tissue. That receptor is the main switch for breaking down stored fat in fat cells, and obese mice have suppressed levels of it. Treatment brought those levels back up to those seen in lean mice. When the researchers repeated the experiment in mice bred without the beta-3 receptor, neither GH nor AOD-9604 changed body weight or fat breakdown, which points to that receptor as the route.
What the research found
Animal studies
- Obese mice (Heffernan, 2001). Fourteen days of injections of either human GH or AOD-9604 reduced body weight and body fat in obese mice. The effect disappeared in beta-3 receptor knockout mice.
- Rabbit osteoarthritis (Kwon and Park, 2015). A separate line of work tested AOD-9604 injected into the knee joint, alone or with hyaluronic acid, in a rabbit model of osteoarthritis. This is unrelated to fat loss and remains animal work.
Human studies
Stier, Vos and Kenley (2013) summarised six randomised, double-blind, placebo-controlled trials run during the drug's development. They focused on the side effects linked to growth hormone. The findings:
- No effect on serum IGF-1.
- No negative effect on carbohydrate metabolism, unlike full-length GH.
- No anti-AOD-9604 antibodies detected.
- No serious adverse events or withdrawals attributed to AOD-9604, and a tolerability profile the authors described as indistinguishable from placebo.
The abstract does not report weight-loss results, and the drug was not approved. The honest summary: good safety data in humans, a fat-loss effect in mice, and no regulatory evidence that the effect carries over to people.
Side effects reported in studies
In the six human trials, adverse events were reported at rates similar to placebo, with no serious events linked to AOD-9604. The research gives no reason to expect GH-type effects such as fluid retention or raised blood sugar, because IGF-1 and glucose handling did not change. Long-term data beyond the trial periods does not exist. For general injection hygiene see the side effect management guide.
AOD-9604 vs growth hormone and tesamorelin
| Compound | What it is | Raises IGF-1 | Status |
|---|---|---|---|
| AOD-9604 | 16 amino acid GH tail fragment | No (human trials) | Never approved |
| Growth hormone | Full 191 amino acid hormone | Yes | Approved medicine |
| Tesamorelin | GHRH analogue | Yes | US-approved for HIV-associated visceral fat |
If the goal is visceral fat reduction with human outcome data, tesamorelin has the stronger evidence base. See also HGH vs peptides.
Status in the Philippines
AOD-9604 is not registered with FDA Philippines and cannot be sold as a medicine. It is sold locally as a research compound. For anyone who competes, WADA lists it under S0, non-approved substances, so it is prohibited at all times.
Storage
Lyophilised powder is best kept refrigerated. Once reconstituted with bacteriostatic water, store at 2 to 8°C and away from the freezer compartment. In the Philippines, plan for brownouts with a cooler and ice packs, since heat is the main cause of peptide degradation. The reconstitution calculator covers the arithmetic.
