Vol. 3, No. 6 — June 2026Independent since 2024

TheCompound Journal

Reporting on incretins, compounding & the peptide supply chain

A monthly journal of record.
30 issues · 32 contributors
Not medical advice. We sell nothing.

Testing Dispatch

Independent analysis puts a CPC orforglipron lot at 95.3%, against 92.5% on the certificate

The result is unremarkable. What the report omits is not.

An independent purity determination on orforglipron material sold by CPC has returned 95.3%, a figure 3.6 percentage points below the number printed on the accompanying certificate. The analysis was performed by Janoshik on a vial the Journal bought as an ordinary retail customer in August 2025 and posted unopened.

The Journal purchased 600 vials from the same lot and had 4 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 Journal purchased 600 vials from the same lot and had 4 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.

Discrepancies of one to two percentage points between a supplier’s figure and an independent determination are common and usually explicable: a faster gradient resolves fewer impurities, a higher integration threshold discards more small peaks, and a wider solvent-front exclusion window removes early-eluting fragments from the calculation altogether. None of that is misconduct. All of it is invisible unless the method is disclosed.

"The useful thing in that report is not the percentage, it is the system suitability data," said Lorcan Feeney, analytical services director at an independent laboratory. "It is the only part that tells you whether the percentage means anything."

CPC’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.

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