Independent analysis puts a JEEP semaglutide lot at 98.0%, against 96.9% on the certificate

A peptide content determination commissioned by the Journal on a 20 mg semaglutide vial from JEEP has returned 96% of the labelled mass, the balance being the counter-ion and residual water that every lyophilised salt carries. Chromatographic purity on the same vial was above 98.0%. The two numbers measure different things, and this is one of the few certificates in the trade to print both.

The Journal purchased 10 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.

"Ask for the suitability summary before you argue about the percentage," said Dr Sirichai Boonmee, peptide chemist, Chulalongkorn University. "If the tailing factor and the replicate precision are outside limits, you are arguing about arithmetic performed on an unfit separation."

JEEP’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.