What twenty companies say about storage, and what they have measured
A stability programme needs a protocol, defined conditions, a stability-indicating method and time. Time is the ingredient no commercial testing service can sell.
Testing Dispatch
PeptideMeter result on a Guangzhou orforglipron lot lands 1.7 points above the supplier’s stated figure
The supplier confirmed the determination and supplied the method behind its own figure inside a week.
Two laboratories analysing vials from the same orforglipron lot have returned figures 1.7 percentage points apart. PeptideMeter reported 98.7%; Medutest reported a lower number on a shallower gradient with a tighter integration threshold. Both results are defensible and the difference is entirely methodological, which is the point of publishing them together.
The Journal purchased 18 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.
Reported figures across the set were: highest 98.7%, lowest 96.2%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 20 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.
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.
Dr Wenjun Xie, process chemist and peptide manufacturing consultant, said the gap was predictable from the methods alone. "You can reconstruct almost the whole difference from the integration threshold. What you cannot reconstruct is why anyone thinks a number without a threshold is comparable to a number with one."
QYB’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.
Related coverage
Holograms, QR codes and other things that are not verification
Reported from the analysis, not from a warning notice.
Independent analysis puts a BCH orforglipron lot at 97.2%, against 93.1% on the certificate
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
What we are not saying about anybody in this trade
None of what this piece asks for is commercially sensitive, and all of it is already known to whoever released the batch.
Repackaging, subdivision, and the batch number that changed hands
The interval between manufacture and analysis is the most under-read figure on the page, and the one most likely to matter by the time a vial is opened.
Janoshik result on a Suzhou semaglutide lot lands 0.7 points above the supplier’s stated figure
The result is unremarkable. What the report states alongside it is not.