Does Fragment 176-191 work?
Not properly: animal or lab studies, or small uncontrolled human reports. Human trials of about 500 people did not show weight loss.
The published evidence for fat loss is three rodent studies. The first found that the fragment blocked fat formation in rat fat tissue, with no lipolytic effect. The other two showed reduced weight gain and more fat breakdown in obese mice. 123 Human trials of AOD9604, the same fragment with a tyrosine added, were run by its developer between 2001 and 2006 in 893 adults; the largest gave it to 502 obese adults for 24 weeks. Only the safety data were published, so for the claimed use there is no positive human evidence. 6
No peer-reviewed human trial of fragment 176-191 or AOD9604 for fat loss has been published. Metabolic Pharmaceuticals ran phase 2 trials of oral AOD9604 in obese adults in the mid-2000s. One lasted six months and had several hundred participants. In 2007 the company announced that the drug had not produced significant weight loss compared with placebo. It abandoned development for obesity. Reviews of obesity drugs list it among the discontinued candidates. 4
Evidence checklist
- Randomised controlled trial Rodent studies only; human trials unpublished
- Human study over 100 people No published human study
- More than one research group Developer's human trials failed, unpublished
- Clinical outcomes, not surrogate markers No positive human outcome
- Human safety data beyond case reports Only the developer's reports; no repeated-use data
Read the full Fragment 176-191 page
More on Fragment 176-191
Citations
- Wu and Ng 1993, Biochemistry and Molecular Biology International: antilipogenic action of synthetic C-terminal sequence 177-191 of human growth hormone pubmed.ncbi.nlm.nih.gov
- Ng 2000, Hormone Research: metabolic studies of a synthetic lipolytic domain (AOD9604) of human growth hormone pubmed.ncbi.nlm.nih.gov
- Heffernan 2001, International Journal of Obesity: increase of fat oxidation and weight loss in obese mice with growth hormone or a modified C-terminal fragment pubmed.ncbi.nlm.nih.gov
- Kakkar and Dahiya 2013, Current Cardiology Reviews: obesity pharmacotherapy, current perspectives and future directions pubmed.ncbi.nlm.nih.gov
- Ng 2000, Hormone Research: metabolic studies of AOD9604 (DOI record) doi.org
- Stier 2013, Journal of Endocrinology and Metabolism: safety and tolerability of the hexadecapeptide AOD9604 in humans doi.org
Reference information only, not medical advice. Drawn from the Fragment 176-191 article, fact-checked against the cited sources. No dosing anywhere on this site.