Patent ID: 8624004

Claim:
A method for producing a stable, immunogenic hepatitis B vaccine without thiomersal suitable for human use, the method comprising: (a) expressing the hepatitis B surface antigen (HBsAg) as a recombinant protein in Saccharomyces cerevisiae; (b) processing the yeast cells to provide a crude antigen preparation; (c) subjecting the crude antigen preparation to gel permeation chromatography, wherein the elution buffer used in the gel permeation chromatography does not contain thiomersal, thereby producing an antigen-containing eluant; (d) subjecting the antigen-containing eluant from step (c) to ion exchange chromatography; (e) adding cysteine to the antigen-containing eluant obtained after step (d); (f) subjecting the preparation from step (e) to ultracentrifugation, thereby obtaining a purified HBsAg; and (g) combining the purified HBsAg with a pharmaceutically acceptable excipient to produce a stable, immunogenic hepatitis B vaccine suitable for human use; wherein the HBsAg is maintained in a soluble form through steps a to g, and wherein no thiomersal is added to the resulting vaccine.