This guidance document ICH Q6B provides a uniform set of internationally accepted specifications for the characterization of biotechnological and biological products to support new marketing applications.

These specifications establish the set of criteria to which a drug substance, drug product or materials at other stages of the manufacturing process should conform in order to be considered acceptable for its intended use. They are one part of the total strategy designed to ensure both product quality and consistency.

Although ICH Topic Q6B does not recommend specific test procedures or specific acceptance criteria it suggests technical approaches which may be considered to provide the following information for biotechnological or biological products:




1. Structural characterization

Amino acid sequence

Amino Acid Sequence of protein as compared to theoretical sequence

Amino acid composition

Amino acid composition of unknown protein

N/C-terminal sequencing

Identify nature and homogeneity of termini

Peptide map

Confirm identity of protein after digestion

S-S-Bridge analysis

Confirm location and /or connectivity of S-groups

Glycosylation analysis

Sugar content and further analysis (structure, modification site)

2. Physicochemical properties

Molecular weight (MW) and size

MW of protein

Isoform pattern

Relative quantification of all isoforms

Extinction coefficient (EC)

EC of known substance

Electrophoretic patterns

Show the identity, homogeneity and purity of a substance

Liquid chromatographic patterns

Show the identity, homogeneity and purity of a substance

Spectroscopic Profiles

Determine higher-order structure

Via Partner

3. Process- and product-related impurities

Host cell proteins

Find contamination via host cell proteins

Truncated forms

Find truncated forms of a protein

Post-translational modifications (PTM)

Identification of PTMs


Find protein complexes

Protagen Protein Services GmbH provides a strategic approach for characterizing your biopharmaceutical products. Analysis is performed in a GMP compliant laboratory using validated techniques to satisfy the latest regulatory requirements.

Your contact for ICH Q6B at Protagen Protein Services GmbH

Thomas Flad

Dr. Thomas Flad

Director Business Development
Our business development team will be happy to assist you with your project.

Phone: +49 (0) 231 9742-6100