Peptency Academy · Research progress
TGA laboratory test: a product sold as retatrutide held semaglutide
The laboratory of Australia's medicines regulator, the TGA, found undeclared semaglutide and no retatrutide in a product sold as retatrutide, according to a safety advisory published on 14 Sep 2026. Source sentence
"TGA laboratory testing of the product found that: the product contained undeclared semaglutide and no retatrutide."; Published 14 September 20261 TGA safety advisory, 14 September 2026 Retatrutide (PubChem CID 171390338, about 4731 Da) and semaglutide (PubChem CID 56843331, about 4114 Da) are two different peptides with different formulas. Source sentence
PubChem PUG REST: substance records named retatrutide (for example SID 438519203) map to CID 171390338; MolecularFormula C221H342N46O68; MolecularWeight 4731; PubChem CID 56843331: title Semaglutide; synonyms include NN9535; MolecularFormula C187H291N45O59; MolecularWeight 41142 PubChem CID 1713903383 PubChem CID 56843331
Research progressAcademy14 September 2026Regulator action
What happened
Australia
- The TGA published the safety advisory on 14 Sep 2026. Source sentence
Safety advisory, Published 14 September 2026
1 TGA safety advisory, 14 September 2026 - The TGA obtained the sample in its original unmarked vial during an investigation. Source sentence
"During its investigation, the TGA obtained a sample of the product contained in its original unmarked vial."
1 TGA safety advisory, 14 September 2026 - The TGA reports the semaglutide level as about 8 times the level it found in semaglutide products included in Australia's official register (ARTG). Source sentence
"the amount of semaglutide detected was approximately 8 times higher than the level found in semaglutide products assessed by the TGA and included in the Australian Register of Therapeutic Goods."
1 TGA safety advisory, 14 September 2026
Why it matters for researchers
- It is a regulator laboratory record of a wrong molecule, not a content shortfall: the vial held a different incretin peptide than its name. Source sentence
"the product contained undeclared semaglutide and no retatrutide"
1 TGA safety advisory, 14 September 2026 - PubChem lists the two peptides with different formulas and masses: C221H342N46O68, about 4731 Da, for retatrutide and C187H291N45O59, about 4114 Da, for semaglutide. Source sentence
PubChem PUG REST: substance records named retatrutide (for example SID 438519203) map to CID 171390338; MolecularFormula C221H342N46O68; MolecularWeight 4731; PubChem CID 56843331: title Semaglutide; synonyms include NN9535; MolecularFormula C187H291N45O59; MolecularWeight 4114
2 PubChem CID 1713903383 PubChem CID 56843331 - A separate 2026 letter covers the other case, products sold as retatrutide that held the right molecule at a different amount (PMID 42559975). Source sentence
Discussion: "all samples contained the expected peptide, but the quantity present varied substantially from the labelled content"
4 Drug Alcohol Rev 2026
What is not known
- The advisory does not name the seller or the supply route of the sampled product. Source sentence
Advisory text, full page read 13 Oct 2026
1 TGA safety advisory, 14 September 2026 - The advisory does not name the analytical method the TGA laboratory used. Source sentence
Advisory text, full page read 13 Oct 2026
1 TGA safety advisory, 14 September 2026 - The advisory reports one sample; how many other products were tested is not stated. Source sentence
"the TGA obtained a sample of the product"
1 TGA safety advisory, 14 September 2026
Regulator actions
Australia
- , Australia, TGA, alert: Laboratory test of a product sold as retatrutide found undeclared semaglutide and no retatrutide. 1 TGA safety advisory, 14 September 2026
Sources
- 1TGA safety advisory, 14 September 2026 accessed 13 Oct 2026
- 2PubChem CID 171390338 accessed 13 Oct 2026
- 3PubChem CID 56843331 accessed 13 Oct 2026
- 4Drug Alcohol Rev 2026 accessed 13 Oct 2026
About this page
Research-use information. This library summarises published literature and regulator records. It is not guidance for use, not medical advice, and not a statement that any material is suitable for use in people or animals.
Reviewed by the Peptency editorial process. Version 1, last edited 13 October 2026, 4 sources.
Cite this page: Peptency Academy. TGA test: product sold as retatrutide contained semaglutide. Version 1./us/academy/news/tga-lab-test-product-sold-as-retatrutide/