VendorInvestigate result on a Xi'an retatrutide lot lands 1.1 points below the supplier’s figure

Two laboratories analysing vials from the same retatrutide lot have returned figures 1.1 percentage points apart. VendorInvestigate reported 98.5%; Janoshik reported a lower number on a shallower gradient with a tighter integration threshold. Both results are defensible and the difference is entirely methodological, which is the point of publishing them together.

Reported figures across the set were: highest 98.5%, lowest 95.4%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 14 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.

Reported figures across the set were: highest 98.5%, lowest 95.4%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 14 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.

The wider context is that material sold for research use carries no regulatory release specification in any jurisdiction the Journal has examined. A certificate is a commercial document, not a compliance one, and its content is whatever the issuer chooses to put on it. That is the gap independent testing fills, and it fills it imperfectly.

Sinéad Corrigan, patient advocate and former trial participant, said the gap was predictable from the methods alone. "You can reconstruct almost the whole difference from the integration threshold. What you cannot reconstruct is why anyone thinks a number without a threshold is comparable to a number with one."

KP’s dossier has been updated with this determination and with the date of the request for comment. The dossier’s "what we could not verify" box records the questions still outstanding.