What changed at Homopeptide in January, and what the company will not say about it
Documentation practice is the only part of vendor quality a buyer can assess before purchase.
TheCompound Journal
Reporting on incretins, compounding & the peptide supply chain
Testing Dispatch
The report states the gradient, the wavelength and the integration threshold, which is more than most.
Medutest has released a batch of 20 analytical reports on research-grade orforglipron lots, including material from WWB and Homopeptide. Reported purities range across roughly 1.0 percentage points, and the report set is unusual in stating the analytical method for every determination rather than for some of them.
Reported figures across the set were: highest 98.6%, lowest 97.7%, 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.
The Journal purchased 3000 vials from the same lot and had 20 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.
Four independent services — Medutest, PeptideMeter, and the two others operating in this market — carry the analytical burden for a trade that has no release-testing obligation of its own. Each is paid by whoever submits the sample, which is usually the vendor. The Journal’s position is that a submitter-pays model is workable but that its incentive structure has to be stated whenever a result is quoted as verification.
"The figure is not wrong and neither is theirs," said Alastair Renshaw, pharmaceutical supply-chain consultant. "They are answers to two different questions and the trade has decided to pretend there is only one question. Print the gradient and the argument disappears."
WWB’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.
Documentation practice is the only part of vendor quality a buyer can assess before purchase.
The ionisation method determines the charge states you see, the adducts you must account for, and the modifications you might destroy in the process.
Reported from the analysis, not from a warning notice.
Reported from the analysis, not from a warning notice.
Deamidation adds 0.98 daltons. On a low-resolution instrument at incretin molecular weights, that is inside the noise.
An in-use period is established by a dedicated study on a specific formulation in a specific container at a specific concentration. Borrowing one from a marketed product is…