OPTIONS trial
The FDA review describes a randomised, double-blind, placebo-controlled study in 502 adults with obesity. The primary analysis found no significant weight-loss difference. [1]
Compound evidence dossier · C-018
AOD-9604 and HGH fragment 176-191
Two market names for a growth-hormone fragment developed for obesity. The principal human programme did not demonstrate the intended weight-loss effect.
What does the evidence say?
AOD-9604 and HGH fragment 176-191 refer to the same peptide fragment, and the main human obesity trial did not show a significant weight-loss benefit against placebo. Earlier work included small or incompletely reported studies, but the larger OPTIONS programme failed its primary efficacy test. That negative result matters more than the continuing mechanistic sales story.
Claim check
Which claims survive an evidence check?
Each row keeps the claim, its best supporting evidence and the limiting caveat together.
AOD-9604 and HGH 176-191 are different compoundsNo
The names refer to the same amino-acid fragment derived from the C-terminal region of human growth hormone. Different labels should not be counted as independent evidence or separate mechanisms.
Human trials proved fat lossNot demonstrated
The 502-participant OPTIONS trial found no statistically significant difference from placebo on its primary weight-loss endpoint after 12 weeks. [1]
Early positive signals outweigh the large trialWeak inference
Some earlier reports were small or available mainly as abstracts. A later, larger randomised programme with a specified primary endpoint carries more weight for the efficacy question.
A fragment avoids growth-hormone risksUnresolved
The intended design was to separate lipolytic effects from growth effects. That rationale does not create a complete human safety file, and the FDA reports insufficient safety information for proposed compounded routes.
Human evidence
What have studies in people shown?
This is a useful example of why study hierarchy matters. A plausible mechanism and small early signals did not translate into a positive main obesity trial.
Signals with reporting limits
Earlier clinical work did not provide a consistent, well-reported efficacy result. One larger abstract described a small effect at one tested condition, but full methods and results were not available for a firm judgement.
Animal metabolism findings
Rodent work supported further study of the fragment. It cannot rescue a failed human efficacy endpoint. [3]
Critical distinction
How to read a negative trial without overclaiming
A negative primary endpoint means the trial did not demonstrate the effect it was designed to test. It does not prove that every possible effect is impossible.
- What failed
- The main comparison for weight loss in the larger obesity programme.
- What remains possible
- Different endpoints or populations can be studied, but they need prospective trials rather than reinterpretation of a failed endpoint.
- What cannot follow
- A biochemical rationale cannot be presented as established fat loss after the main human trial is negative.
- Why market names matter
- Using “HGH fragment” instead of AOD-9604 does not reset the evidence record.
Risk register
What could go wrong?
The efficacy verdict and safety verdict are separate. A failed efficacy trial does not prove safety, and sparse safety evidence cannot support reassurance.
| Risk channel | Evidence-aware interpretation |
|---|---|
| Trial evidence | The available regulator review did not identify a demonstrated weight-loss benefit. |
| Safety dataset | The FDA says it has no or limited safety-related information for compounded AOD-9604 and cannot determine whether it would cause harm by proposed routes. |
| Product quality | Potential aggregation, immunogenicity, peptide-related impurities and API-characterisation problems are product-level concerns. |
| Unknowns | Repeated exposure, interactions, vulnerable populations and risks from current non-authorised formulations are not adequately defined. |
Product evidence
What would evidence about a vial prove?
A compound-level literature verdict and a product-level finding answer different questions. Neither can substitute for the other.
Claimed compound
The literature applies only if the vial contains the same active substance and form that the source studied.
Label and release record
A batch-specific record should identify the material, method, result, specification and accountable laboratory.
Submitted sample
A defensible result concerns the sample tested. It does not certify every vial, future batch or storage condition.
Clinical meaning
Identity, purity and sterility evidence cannot establish a health outcome or fill a missing human safety dataset.
Status check
Is it authorised or prohibited?
Medicine authorisation, lawful supply and anti-doping status are separate checks. Each can change and should be verified at the point of decision.
| System | Finding checked 8 August 2026 |
|---|---|
| UK medicine status | No AOD-9604 or HGH fragment 176-191 medicine with a UK marketing authorisation was identified in the MHRA database check. |
| United States | AOD-9604 is not an FDA-approved medicine. The FDA compounding review found insufficient evidence of effectiveness and important characterisation and safety gaps. |
| Sport | The 2026 WADA list gives AOD-9604 and hGH 176-191 as examples of prohibited growth-hormone fragments. The prohibition applies at all times. |
Method note
How was this judgement made?
We prioritised the regulator’s reconstruction of the clinical programme because it links study design, population and primary endpoint. Preclinical metabolism work was retained as mechanism evidence only.
Searches prioritised regulator documents, current medicine and anti-doping records, trial registrations and indexed primary studies. Seller pages were not used as evidence of efficacy or safety.
Read the full editorial method and inspect the evidence library.
Source ledger
Primary sources
- US FDA, AOD-9604 Pharmacy Compounding Advisory Committee briefingReconstruction of the human obesity programme, safety evidence and regulatory assessment. Checked 8 August 2026.
- US FDA, Certain Bulk Drug Substances That May Present Significant Safety RisksCurrent regulator summary of characterisation, impurity, immunogenicity and safety concerns. Checked 8 August 2026.
- Heffernan et al., AOD-9604 metabolic studyAnimal evidence; not a human weight-loss trial. Checked 8 August 2026.
- World Anti-Doping Agency, 2026 Prohibited ListCurrent list used for sport-status checks; effective 1 January 2026. Checked 8 August 2026.
- MHRA ProductsPublic UK medicines database used for the marketing-authorisation check. Checked 8 August 2026.
Questions answered
Frequently asked questions
Short answers keep the decisive caveat beside the claim.
Are AOD-9604 and HGH fragment 176-191 the same?
Yes. They are names used for the same 16-amino-acid fragment from the C-terminal region of human growth hormone. Switching the name does not create a different clinical evidence base.
Did AOD-9604 work in human weight-loss trials?
The main 502-person OPTIONS trial did not show a statistically significant advantage over placebo on its primary weight-loss endpoint. Earlier studies did not provide a stronger, consistently reported result.
Does a negative trial prove the peptide can never work?
No. It means that trial did not demonstrate its prespecified effect. A different claim would need a suitable new trial; a mechanistic explanation cannot be used to rewrite the negative result.
Is AOD-9604 authorised as a medicine?
No UK or US authorised AOD-9604 medicine was identified. Regulatory status can change, so the relevant medicines database should be checked at the point of decision.
Is AOD-9604 prohibited in sport?
Yes. The 2026 WADA list names AOD-9604 and hGH 176-191 as prohibited growth-hormone fragments. The rule applies at all times.
Can purity testing show that AOD-9604 causes weight loss?
No. Analytical testing may support sample identity or purity. It cannot establish efficacy, long-term safety or equivalence to the material used in a clinical trial.
Evidence library
Claim-level evidence records
Open the individual records behind this profile. Each record links to the primary and official sources used for its verdict.
Profile-to-record links checked 10 August 2026. These evidence records received named scientific and clinical sign-off on 10 August 2026.
Editorial experience
From our work: how we checked this page
For topical-map item C-018, AOD-9604 and HGH fragment 176-191 was checked as a distinct editorial task, not treated as a generic peptide page. We reviewed 5 unique external sources and 9 internal destinations in the page, then checked that the opening answer, headings, source descriptions and linked next steps stayed within the same claim boundary. The count records links in the published page and is not a claim that every source carries equal evidential weight.
Eleni Kiromitis checked study design, biomedical evidence, evidence directness and laboratory context. Dr Stavroula Nikitopoulou checked clinical claims, adverse effects, contraindications, red flags and patient-facing safety wording. Each reviewer stayed within the remit published on the governance page. Yianni Kiromitis retained responsibility for source verification, editorial decisions and correction management.
We did not use patient experience, a personal treatment outcome, seller testimony or an assumed product identity to support this page. The publication did not independently test a vial for this review. Where a page refers to a laboratory result, that result applies only to the named sample, method and attribute. We kept uncertainty beside the conclusion, recorded which source supports each material claim, and checked that the visible review date matches the publication record. A new controlled study, regulator update, corrected source, analytical report or credible safety signal can trigger reassessment through the public correction route.