Independent analysis puts a QYB liraglutide lot at 96.9%, against 96.0% on the certificate

An independent purity determination on liraglutide material sold by QYB has returned 96.9%, a figure 2.7 percentage points below the number printed on the accompanying certificate. The analysis was performed by Medutest on a vial the Journal bought as an ordinary retail customer in March 2025 and posted unopened.

The Journal purchased 2900 vials from the same lot and had 23 of them analysed separately, in order to distinguish vial-to-vial variation from method variation. Vial-to-vial agreement was within 0.4 percentage points. Method-to-method disagreement was an order of magnitude larger.

Reported figures across the set were: highest 96.9%, lowest 96.0%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 23 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.

Havel Novotný, independent laboratory quality manager, 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."

QYB’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.