AOD-9604 Legal and Patent Challenges: FDA Status, Regulatory History, and Compounding Access

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Is AOD-9604 FDA-approved?

No. AOD-9604 was developed by the Australian company Metabolic Pharmaceuticals as an anti-obesity drug candidate, and phase IIa trials were under way by February 2002 [4]. It never reached approval, and the obesity program was later dropped [5].

The main human test was a 24-week study of an oral formulation: 534 people were enrolled and 502 randomized, and the drug failed to show a significant benefit on the primary weight-loss endpoint [5]. That result rests on sponsor-reported phase 2 data rather than a peer-reviewed randomized trial, and the same 2026 review notes there are no robust human data for visceral-fat reduction or other metabolic benefit [5].

The peptide still circulates on the gray market: Belgian authorities identified it in unknown pharmaceutical preparations they seized [9], and US investigators found it in confiscated vials [10].

What FDA's compounding lists say about AOD-9604

FDA's page on bulk drug substances that may present significant safety risks when compounded, with content dated 04/22/2026, places AOD-9604 in the table of substances that were previously in category 2 and whose nominators then withdrew them [1]. FDA's stated concerns are specific: compounded drugs containing AOD-9604 may pose a significant immunogenicity risk for certain routes of administration because of peptide impurities and characterization problems; FDA identified no, or only limited, safety information; and FDA identified serious adverse events that may be associated with AOD-9604, though causality is not clear [1]. Removal from category 2 was not a finding that the substance is safe [1].

AOD-9604 appears in none of the three categories on FDA's list for state-licensed pharmacies and physicians, updated May 14, 2026, and it does not appear on FDA's separate list for outsourcing facilities, updated March 21, 2025 [11][12][6]. Category 1, the policy under which FDA says it generally does not intend to act against a compounder when the stated conditions are met, therefore does not cover it [6].

Two 2026 developments are sometimes read as opening the door to peptide compounding. Neither names AOD-9604. HHS's draft enforcement-discretion policy for compounding, filed October 28, 2026 as Federal Register document 2026-22192 with publication scheduled for October 30, 2026, covers six peptides: BPC-157, epitalon, KPV, MOTS-c, Semax and TB-500 [2][13]. FDA's Pharmacy Compounding Advisory Committee met on July 23-24, 2026 to discuss BPC-157, KPV, TB-500, MOTS-c, emideltide, Semax and epitalon [3].

Compounded drugs in general are not FDA-approved, and FDA does not review their safety, effectiveness or quality before they are marketed [2][13][3].

Where the GRAS claim comes from

FDA's GRAS Notice Inventory contains no AOD-9604 notice. Searches of the inventory for AOD9604, AOD, growth hormone and peptide returned no entry, so there is no FDA no-questions letter for it [7]. Claims that AOD-9604 is GRAS trace back to the developer, which announced in 2012 a conditional GRAS conclusion by a panel it commissioned, for use as a food or drink ingredient at up to 1 mg per day. That was not an FDA review [7].

GRAS is a food-ingredient concept, and a GRAS conclusion would not make an injectable lawful as a drug [7].

Do a prescription or an expired patent change the federal position?

No. For state-licensed pharmacies and physicians, FDA says a bulk drug substance may be used in compounding only if it complies with an applicable USP or NF monograph, is a component of an FDA-approved drug product, or appears on FDA's bulks list [6]. A prescription or patent expiry is not among those conditions [6]. AOD-9604 is not an FDA-approved drug and is not in any category on FDA's compounding lists [4][5][11][12][6].

The commercial record that is documented is short. Metabolic Pharmaceuticals took the compound into phase IIa trials for obesity by February 2002 [4], and the program was later dropped after the 24-week oral study missed its primary endpoint [5]. The molecule itself is hGH amino acids 177 to 191 with an extra tyrosine added at the N-terminus, 16 amino acids in total, which is why it is also called hGH fragment 176-191 [10].

Is AOD-9604 prohibited in sport?

Yes. WADA's Prohibited List names AOD-9604 and hGH 176-191 in section S2.2.3, growth hormone fragments. It is prohibited at all times, in and out of competition, and S2 substances are non-Specified Substances [8]. It appears on the 2026 List, in force since January 1, 2026, and remains on the 2027 List in the tracked-changes version dated 26 August 2026 [8][14].

Detection work exists for it. Anti-doping scientists validated a urine solid-phase extraction method with a limit of detection of 50 pg/mL, identified six potential metabolites, and found a single stable metabolite, the peptide CRSVEGSCG, that is significantly more stable than the parent compound; screening for both may potentially allow an increased window of detection [10].

What is on record about safety

FDA states that it identified serious adverse events that may be associated with AOD-9604, gives no details, and says causality is not clear [1]. A 2026 review concludes that human evidence is limited and largely short-term [5]. A second 2026 review of unapproved peptides used in sports medicine notes that many show favorable tissue-repair and metabolic results in animals, but that rigorous human safety data are scarce and there is potential for serious harm [15].

The animal work is where the positive results sit. In obese Zucker rats, oral AOD9604 at 500 microgram/kg daily for 19 days cut body-weight gain to 15.8 g versus 35.6 g in controls and did not worsen insulin sensitivity on euglycemic clamp testing [16]. In obese mice, 14 days of treatment reduced body weight and body fat, an effect that was not seen long-term in mice lacking the beta-3 adrenergic receptor [17]. Preclinical work also found no growth-hormone-receptor binding [18][5].