21 CFR 211.167(a) Special testing requirements

This FDA cGMP regulation requires that each batch of drug product that purports to be sterile and/or pyrogen-free must undergo appropriate laboratory testing to confirm those claims before release for distribution.

Sterile products: Must be tested to verify sterility.

Products labeled as pyrogen-free: Must be tested for pyrogens (e.g., bacterial endotoxins).

The rule applies broadly based on the product’s labeling claims, not dosage form. It is distinct from microbiological testing of non-sterile products, which addresses “freedom from objectionable microorganisms” under separate requirements.

Takeaway: 21 CFR 211.167(a) ensures that patient-critical safety attributes—sterility and pyrogen-free status—are directly confirmed for every batch, forming a non-negotiable release requirement under FDA cGMP.

Applies to all sterile or pyrogen-free drug products, regardless of dosage form. Testing must be conducted on each batch prior to release. Distinct from microbiological limits testing for non-sterile products.