Merck + Co., Inc.

Dennis J Kubek

Peter J Kniskern

William J Miller

Arpi Hagopian

Pamela D Burke

Charlotte C Ip

John P Hennessey

Richard L Tolman

Stephen Marburg

Robert D Sitrin

John P Hennessey Jr

Type-specific capsular polysaccharide preparations from Streptococcus pneumoniae, having on average less than about 1000 oligosaccharide repeat units per molecule, polydispersities between 1.0 and 1.4, intrinsic viscosities between 0.6 and 3.0 dL/g, and less than 3% contamination of type-specific polysaccharide by group-specific C-polysaccharide, are produced by a novel process. The novel type specific polysaccharide products are useful in the preparation of vaccines, especially covalent conjugates comprising the novel polysaccharide linked to a T-cell stimulatory carrier protein. Vaccines comprising the novel polysaccharides are useful in the prevention of infection and of diseases associated with infection by Streptococcus pneumoniae.

Process for making capsular polysaccharides from Streptococcus

A novel conjugate vaccine comprising partially hydrolyzed, highly purified, capsular polysaccharide (Ps) from Streptococcus pneumoniae bacteria (pneumococci, Pn) linked to an immunogenic carrier protein, is produced by a new process. The conjugate is useful in the prevention of pneumococcal infections. Vaccines comprising a mixture of from one to ten different pneumococcal polysaccharide-immunogenic protein (Pn-Ps-PRO) conjugates induce broadly protective recipient immune responses against the cognate pathogens from which the polysaccharide components are derived. Young children and infants younger than 2 years old, normally unable to mount a protective immune response to the Pn-Ps alone, exhibit protective immune responses upon vaccination with these Pn-Ps-PRO conjugates.

Pneumococcal polysaccharide conjugate vaccine

Recombinant hepatitis B virus surface proteins produced in recombinant host cells are rapidly and efficiently purified from either cell extracts in a high pH buffer, or from heated whole cells at neutral pH. The host cell extracts or whole cells are heat treated, cooled and in the case of high pH extract, the pH is reduced. The surface proteins are then absorbed onto wide pore silica followed by elution and concentration. This method eliminates the requisite introduction of protease inhibitors, stabilizes the surface protein and improves product yield.

Method of stabilizing recombinant hepatitis B virus surface proteins

A liquid phase containing preS2+S antigen is separated into two phases after which the desired antigen is concentrated, washed and adsorbed and desorbed from a fumed silica to produce a product that is purified and concentrated in antigen:protein ratio and that is suitable for final purification.

Recovery of pres2+s antigen

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Salem, WV, United States of America

Dennis J Kubek