Independent analysis puts a FGP exenatide lot at 95.8%, against 93.2% on the certificate

PeptideMeter has published a purity determination of 95.8% on a 30 mg vial of exenatide supplied by FGP, against a figure of 93.2% on the certificate that accompanied the vial. The sample was submitted by the Journal in April 2026 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 20 vials from the same lot at retail and had four 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.

Purity became this trade’s single figure of merit because it is the cheapest measurement to obtain and the easiest to compare. Peptide content, which determines how much drug is actually in a vial, costs several times as much and is quoted as a priced addition by most of the twenty companies in the Journal’s dossier programme rather than carried as a standard release test. Sterility and endotoxin are separate disciplines again, and are neither tested nor claimed.

"The useful thing in that report is not the percentage, it is the system suitability data," said Dr Sirichai Boonmee, peptide chemist, Chulalongkorn University. "It is the only part that tells you whether the percentage means anything."

FGP’s dossier has been updated with this determination and with the company’s response to it. The dossier’s ordering box records the lead times, the minimum quantities and what a buyer should ask for at the point of order.