VendorInvestigate result on a Shenzhen semaglutide lot lands 1.1 points below the supplier’s figure

An independent purity determination on semaglutide material sold by HJ has returned 99.0%, a figure 1.1 percentage points below the number printed on the accompanying certificate. The analysis was performed by VendorInvestigate on a vial the Journal bought as an ordinary retail customer in June 2025 and posted unopened.

Reported figures across the set were: highest 99.0%, lowest 95.3%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 10 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.

Batch variance rather than vendor quality is the recurring finding of this programme. Across the 10 determinations the Journal has commissioned to date, within-vendor spread has been wider than between-vendor spread for two thirds of the companies tracked, which is an argument against rating any supplier on a single number.

"The useful thing in that report is not the percentage, it is the system suitability data," said Sinéad Corrigan, patient advocate and former trial participant. "It is the only part that tells you whether the percentage means anything."

HJ’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.