Patent ID: 7863426

Claim:
A method for producing a host cell protein (HCP)-reduced antibody preparation from a mixture comprising an antibody and at least one HCP, the method comprising: applying the mixture to a cation exchange resin equilibrated with an equilibration buffer, wherein greater than 30 grams of antibody per liter of cation exchange resin are applied; washing HCP from the cation exchange resin with a plurality of wash steps comprising a first wash and a second wash, wherein conductivity of the first wash is equivalent to conductivity of the equilibration buffer and there is an increase in conductivity with each successive wash in the plurality of wash steps; eluting the antibody from the cation exchange resin with an elution buffer to form a first eluate; applying the first eluate to an anion exchange resin, wherein prior to applying the first eluate to the anion exchange resin, pH and conductivity of the first eluate are adjusted to be substantially similar to pH and conductivity of the anion exchange resin; obtaining a first flowthrough comprising the antibody, and obtaining the HCP-reduced antibody preparation therefrom.