Ultra-high yield intravenous immune globulin preparation

Abstract

An efficacious large-scale alcohol-free plasma fractionation production process which produces a high-yielding, non-denatured, double viral-inactivated intravenous human immune gamma globulin (IgG) product. The process employs sodium citrate in two initial fractionation steps, followed by diafiltration to remove sodium citrate.

Description

FIELD OF INVENTION [0001] This invention relates generally to methods for immune serum globulin purification, and, more particularly, to methods for alcohol-free separation of immune globulin from blood plasma or other blood based material. BACKGROUND AND DESCRIPTION OF RELATED ART [0002] Commonly, contemporary methods for separation of immune globulins (IgG) from blood plasma or other blood based material depend upon early work by Edwin J. Cohn. As found in U.S. Pat. No. 5,177,194 issued Jan. 5, 1993 to Maria E. Sarno, et al. (SARNO), “One scheme in widespread use is the well-known Cohn fractionation method, which is based on differential precipitation using cold ethanol.” Cohn et al. J. Am. Chem. Soc. 68, 459 (1946). [0003] A U.S. Pat. No. 2,390,074 issued Dec. 4, 1945 to Edwin J. Cohn (Cohn) disclosed use of alcohol, acetone and dioxane as precipitants in such fractionation processes. Continued dependence upon alcohol as a precipitant is further demonstrated in U.S. Pat. No. 6,89...

AI Technical Summary

Benefits of technology

[0022] It is well-known that sodium citrate has long been used in low concentrations during the collection, preservation and storage of blood plasma. Subsequent diafiltration after use of high concentrations of sodium citrate as a precipitant substantially reduces the ionic strength and volume of the gamma globulin solution, permitting the achievement of chromatographic purification on an industrial scale.

[0023] Following separation of gamma globulin from plasma by this method, albumin and alpha-1-antitrypsin are subsequently removed from the remaining proteins by methods available from Cohn or others. The process, according to the instant invention, enables the separation of gamma globulin without exposing it to the denaturing effects of ethanol used in the Cohn process, hence leaving the gamma globulin in a native state. The denaturing effects of alcohol include the formation of polymers, aggregates and fragments of the gamma globulin molecule. However, the use of sodium citrate stabilizes the plasma while bringing about precipitation of substantially all of the coagulation proteins, thus preventing the generation of enzyme activators and proteolytic enzymes.

[0025] In summary, the process of the instant invention employs high concentrations of sodium citrate combined with its subsequent removal from the gamma globulin concentrate by means of diafiltration, a technique which became practical on an industrial scale in the 1980's. Final purification of the resulting gamma globulin is then practically and effectively achieved through the use of well-established chromatographic purification techniques. The invention reduces production costs as a result of higher yields, fewer fractionation steps, shorter overall processing time, lower energy costs, and lower chemical costs. Capital costs are less because of reduced space requirements, reduced work-in-process, reduced processing time, and elimination of the explosion proof environments required for ethanol processing.

[0026] Accordingly, it is a primary object to provide an effective intravenous gamma globulin preparation at a cost which is reduced from methods in current practice.

[0028] It is a further object to provide a gamma globulin preparation which can be rapidly infused with greater patient tolerance than gamma globulin produced by methods employing alcohol.

[0030] It is an object to produce gamma globulin having reduced in-process formation of polymers, aggregates, fragments, enzyme activators and proteolytic enzymes compared with similar preparations produced using traditional alcohol based methods.

Problems solved by technology

Even so, the use of alcohol precipitants is not without difficulties, as illustrated by Cohn, “Some protein precipitants, such as alcohol, have a tendency to denature many proteins with which they come in contact, the danger of denaturation increasing with concentration of the alcohol and increase in temperature.

However, the separation of the large-weight, lower-value fractions such as albumin and gamma globulin, on an industrial scale has not been found to be practical.

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