Independent analysis puts a ERP liraglutide lot at 99.4%, against 98.3% on the certificate

An independent purity determination on liraglutide material sold by ERP has returned 99.4%, a figure 2.9 percentage points above the number printed on the accompanying certificate, which the supplier had reported against a shorter gradient and a tighter threshold. The analysis was performed by Janoshik on a vial the Journal bought as an ordinary retail customer in December 2024 and posted unopened.

The Journal purchased 16 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.

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.

Dr Beatriz Sarmiento, clinical pharmacologist, Universidad de Navarra, thought the split-sample design was the useful part. "A single result on a single vial is an anecdote with a decimal point. Pairs from one lot to two laboratories is the cheapest experiment that answers a real question."

ERP’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.