Is AOD-9604 Legal in Washington State? A 2025 Clinical Guide

What AOD-9604 is

AOD-9604 is a 16-amino-acid fragment of human growth hormone, made of hGH residues 177 to 191 with an extra tyrosine at the N-terminus. It is also called hGH fragment 176-191 [5]. Metabolic Pharmaceuticals developed it as an anti-obesity candidate, with phase IIa trials underway by February 2002 [1]. It never reached approval, and the obesity program was later dropped [2].

A 2026 review reports that a 24-week study (534 enrolled, 502 randomized) of oral AOD9604 as an anti-obesity drug failed to show a significant benefit on its primary weight-loss endpoint. The review notes that this conclusion rests on sponsor-reported phase 2 results rather than peer-reviewed randomized trials [2]. There is no approved dose [2].

What FDA's compounding lists say

FDA has a page on bulk substances that may present significant safety risks when compounded (content dated 04/22/2026). On it, AOD-9604 appears in the table of substances nominated but withdrawn, meaning those previously in category 2 whose nominators withdrew them [6]. FDA's stated concerns include:

• potential immunogenicity risk for certain routes of administration, due to peptide impurities and characterization problems;
• no or only limited safety information;
• serious adverse events that may be associated with the substance, though causality is not clear [6].

Removal from category 2 was not a finding that it is safe [6].

AOD-9604 appears in none of the three categories on FDA's list for state-licensed pharmacies and physicians (updated May 14, 2026) or on FDA's list for outsourcing facilities (updated March 21, 2025) [3][7][4]. The category 1 policy, under which FDA generally does not act against compounders that meet its conditions, does not cover it [3][4].

AOD-9604 is not among the six peptides named in HHS's draft enforcement-discretion policy filed October 28, 2026. It was also not on the agenda of FDA's July 2026 Pharmacy Compounding Advisory Committee meeting [8][10].