BRIEFING

 〈326〉 Molar Mass Determination of Bacterial Polysaccharides Used in Human Vaccines by Size Exclusion Chromatography with Multiangle Light Scattering Detection. A new chapter is being proposed by the Biologics Monographs 3—Complex Biologics and Vaccines Expert Committee, applicable to the analysis of bacterial polysaccharides used for the production of human vaccines. Part of USP’s mission is focused on providing standardized analytical testing methodologies based on sound scientific principles that can provide users with data to establish quality specifications and improve characterization of bacterial polysaccharides.

 To provide background and clarity to USP stakeholders, the Biologics Monographs 3 Expert Committee is proposing the following:

1. The scope of this general chapter will only include the analysis of the purified bulk powder polysaccharide used in the manufacture of bacterial polysaccharide vaccines (polysaccharide or protein-polysaccharide conjugates).

2. The Biologics Monographs 3 Expert Committee has agreed to develop this chapter as a below 〈1000〉 general test procedure chapter with a similar approach of other USP general test chapters such as Nuclear Magnetic Resonance Spectroscopy Identity Testing of Bacterial Polysaccharides Used in Vaccine Manufacture 〈198〉.

3. The size exclusion chromatography with multiangle light scattering detection (SEC-MALS) methodology described in this proposed general chapter is currently nonmandatory because it is not cited in either the General Notices, a monograph, or a general chapter numbered below 〈1000〉.

4. The Biologics Monographs 3 Expert Committee will consider the introduction of additional methodologies into this general chapter once supporting data are received. As such, other test articles such as activated polysaccharides or polysaccharide-protein conjugates may be added as future revisions to the chapter.

5. This proposal contains a SEC-MALS method for determination of the molar mass and polydispersity of bacterial polysaccharides. The method is based on a validated SEC-MALS method of analysis performed with a series of Tosoh brand of columns (TSKgel G6000PWXL, TSKgel G5000PWXL, and TSKgel G4000PWXL) with L39 packing. The goal of developing this chapter is to provide a modern improved analytical method to assist and improve characterization of bacterial polysaccharides used in vaccine manufacture, which will help in establishing product quality specifications. Stakeholders are encouraged to contact USP to discuss any additional methods for characterization of bacterial polysaccharides.

 (BIO3: Y. Han)

 Case ID—SUB-1825