A preparation of modified immune serum globulin (human) suitable for intravenous administration. Further characterization and comparison with pepsin-treated intravenous gamma globulin.

Numerous methods have been used in previous attempts to prepare a human gamma globulin solution suitable for intravenous administration. These include fractionation schemes, enzyme digestion, manipulations of pH, and various combinations of these methods. The selective reduction and alkylation process that we have developed for Gamimune causes a controlled and reproducible modification of a limited number of disulfide bonds in the hinge region of IgG, resulting in a functional antibody molecule of undiminished molecular weight and possessing complement-binding properties suitable for intravenous administration. Subtle changes in molecular structure or properties that may be caused by trace enzyme hydrolysis or extremes of pH and temperature are avoided. The biochemical characterization of immune globulin intravenous (Gamimune) is described herein, and the attributes of this chemically modified IgG are compared with some of the other intravenous gamma globulin preparations.