VendorInvestigate result on a Zhuhai survodutide lot lands 3.8 points below the supplier’s figure

VendorInvestigate has published a purity determination of 99.1% on a 30 mg vial of survodutide supplied by TFC, against a figure of 95.1% on the certificate that accompanied the vial. The sample was submitted by the Journal in December 2025 as part of a continuing programme of arm’s-length purchasing, and the vendor was told before the order was placed that any result would be published.

The Journal purchased 3300 vials from the same lot and had 11 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.

The Journal purchased 3300 vials from the same lot and had 11 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.

Batch variance rather than vendor quality is the recurring finding of this programme. Across the 11 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 Rowena Ashcombe, community pharmacist and diabetes educator. "It is the only part that tells you whether the percentage means anything."

TFC’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.