Process for increased yield of immunoglobulin from human plasma

Inventors

NUVULA, ASHOK KUMAR • CHAKRABORTY, ZINIA • BAVIRISETTI, VVS SAILESH • KATKURI, THIRUPATI REDDY • Komath, Uma Devi

Assignees

Ichor Biologics Private Ltd

Abstract

The present invention discloses a preparation method for large scale production of human immunoglobulins (IgG) with high yields by an improved all-chromatography process scheme that eliminates ethanol precipitation. The process of extracting immunoglobulins is such that the other therapeutic proteins in plasma are left unaffected and are available for extraction separately from the same plasma sample. The yields obtained are in the range of 7 to 8 grams of IgG per liter of plasma. The high yielding process scheme of the present invention comprises of chromatographic steps and viral inactivation or removal steps to obtain a purified immunoglobulin protein that complies with pharmacopoeial limits and is suitable for therapeutic administration (normal intravenous immunoglobulin—IVIG).

Core Innovation

The invention relates to a method for obtaining high yield therapeutic grade immunoglobulin (IgG) from human plasma while maintaining an ethanol-free all-chromatography approach that leaves other therapeutic plasma proteins available for separate recovery. The process uses sequential chromatography and purification steps that fractionate plasma, enrich IgG, and remove non-IgG proteins without relying on ethanol.

Human plasma is fractionated on a size exclusion column in citrate, phosphate or acetate buffer salt, and the IgG containing fraction is collected. The IgG containing fraction is then loaded on an anion exchange column to bind non-IgG plasma proteins, and the flow through fraction containing IgG is subjected to euglobulin precipitation.

The euglobulin depleted IgG containing fraction is further processed on an anion exchange column to collect the IgG sample in a flow through fraction, which is then subjected to viral inactivation by two sequential steps comprising incubation and solvent-detergent treatment with Tri-n-butyl phosphate and Triton X-100. Finally, the viral inactivated material is subjected to final purification by a cation exchange resin, with IgG eluted using sodium chloride.

The disclosed approach is reported to provide therapeutic-grade IgG performance, including high yield recovery from plasma and quality attributes such as normal IgG subclass distribution matching plasma, as well as low impurity levels to pharmacopoeial limits, with suitability for IVIG administration.

Claims Coverage

The independent claim recites a multi-step all-chromatography method to obtain high yield therapeutic grade IgG from human plasma, incorporating size exclusion fractionation, anion exchange enrichment, euglobulin precipitation, anion exchange flow-through handling, two-step viral inactivation, and final cation exchange purification. Dependent claims add measurable therapeutic-grade specifications, including IgG yield by a Double Antibody Sandwich ELISA method and defined IgG isoform distribution and impurity limits.

Overall, the claim set covers a defined chromatographic IgG purification workflow from human plasma that proceeds through size exclusion collection, anion exchange enrichment with euglobulin precipitation, an additional anion exchange flow-through step, two sequential viral inactivation steps, and cation exchange final purification. Dependent claims further constrain the therapeutic-grade product by specifying IgG yield by a Double Antibody Sandwich ELISA method and defined IgG isoform distribution and impurity limits.

Stated Advantages

Documented Applications