Certificate of analysis

Also called: COA

Clinical reviewer: Jacob Moore, MD · Last checked September 16, 2026

What is a peptide COA?

Certificate of analysis is a supplier's test report stating a batch's identity, purity and other quality measures. FDA's rule for compounding under section 503A requires bulk drug substances to be accompanied by valid certificates of analysis from an FDA-registered establishment, but manufacturers must still verify identity themselves rather than relying on the supplier's report alone.

What does a certificate of analysis show?

A certificate of analysis, or COA, is a supplier's report of the testing performed on a batch, covering measures like identity, strength and purity. Section 503A requires that bulk drug substances used in compounding be accompanied by valid certificates of analysis and come from an FDA-registered establishment [1]. For an injectable, FDA lists sterility, bacterial endotoxins and foreign particulates as critical quality attributes, and calls the endotoxin test a critical quality control attribute [3].

Why can't a compounder just rely on the supplier's COA?

Federal cGMP rule 21 CFR 211.84(d)(2) allows a manufacturer to accept a supplier's report of analysis only if it also runs at least one specific identity test on the component itself, and only after it has validated the reliability of the supplier's testing [2]. A COA is a starting point, not a substitute for that verification.

Why does grade and testing matter in practice?

FDA has warned compounders about dietary-supplement-grade glutathione linked to at least 30 patients experiencing adverse events, including fever, chills and sepsis-like symptoms consistent with excessive endotoxin, after use in injectables [4]. FDA said ingredients labeled for dietary-supplement use may contain impurities, including endotoxins, that may be harmful when injected [4]; a pharmaceutical-grade COA and identity testing are meant to catch exactly that.

Related terms

Browse all terms

Sources

  1. FDA — Bulk Drug Substances Used in Compounding Under Section 503A
  2. 21 CFR 211.84 — Testing and Approval or Rejection of Components, Drug Product Containers, and Closures
  3. FDA — MOTS-c Briefing Document, Pharmacy Compounding Advisory Committee, July 2026
  4. FDA — Reminds Compounders Not to Use Dietary Supplement Grade Glutathione for Injectables

This entry is for education and is not medical advice. Talk with a licensed clinician about your own situation before starting, stopping, or changing any treatment.

Ready to transform your health?

Take our 2-minute quiz to discover your personalized program for weight loss, longevity, or metabolic health. No commitment — just clarity on what's best for you.