Patent ID: 6709655
Filing Date: 2004-03-23
Classification: A61K,A61P,C07K,Y10S

Abstract:
A method for preparing a composition of F(abâ€²)2 antibody fragments that are substantially free of whole antibodies, which comprises:a) contacting a source of antibody with pepsin under conditions to prepare an antibody digest containing F(abâ€²)2 fragments and being substantially free of unhydrolyzed antibodies; b) treating said antibody digest by two steps of ammonium sulfate precipitation i) one step at about 16% to about 22% weight by volume ammonium sulfate; and ii) another step at about 32% to about 38% weight by volume of ammonium sulfate; to thereby obtain a composition containing F(abâ€²)2 fragments substantially free of whole antibodies.