Arginine inactivation of viruses

Abstract

The present invention pertains to methods of using arginine to inactivate or reduce the infectious titer of enveloped viruses potentially present in biological compositions produced by eukaryotic cells (such as a antibodies or other therapeutic proteins). In some embodiments, inactivation or reduction of viral titers by exposure to arginine is achieved in a neutral (pH˜7) or near neutral (˜pH 6 to ˜pH 8) environment.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation of U.S. patent application Ser. No. 13 / 130,540, which has a §371(c) date of Oct. 4, 2011, and is the National Stage of International Application Number PCT / US2009 / 006221, filed Nov. 20, 2009, which claims the benefit of U.S. Provisional Application No. 61 / 116,534, filed Nov. 20, 2008, each of which is herein incorporated by reference in its entirety.FIELD OF THE INVENTION[0002]The present invention relates to inactivation of viruses or reduction of infectious virus titers. More specifically, the invention relates to inactivation or reduction of infectious virus titers by treatment with arginine or salts thereof. The invention also relates to inactivation or reduction of infectious virus titers as a component of therapeutic product preparation and purification regimens.BACKGROUND[0003]The advent of recombinant DNA technology has opened the door for many protein-based biological therapies. In most circumst...

AI Technical Summary

Benefits of technology

The present invention allows for the use of high concentrations of arginine to effectively inactivate or reduce infectious titers of lipid coated viruses that may be present during the production of a biological product. This helps to create a safer and more reliable protein preparation for therapeutic use. Additionally, the invention can be used in various processes for preparing therapeutically useful proteins.

Problems solved by technology

Viruses can remain in the culture after transfection and contaminate the protein samples.

Additionally, cells used for expressing proteins of interest may encode viral genomes in their DNA or otherwise contain endogenous viruses, which is another potential source of contamination to a therapeutic product derived from cells.

Treatment with low pH, the use of detergents, salts, and heat inactivation have all been used to inactivate viruses in protein preparations, but each method has its own disadvantages, and may not be suitable or optimal for some protein products as discussed in further detail below.

Low pH has been used to inactivate viruses as in U.S. Pat. No. 6,955,917, but this has the potential to precipitate proteins, cause aggregation of the product, and / or alter the conformation of certain proteins which can lead to product loss.

U.S. Pat. No. 6,528,246 B2 describes a method for inactivation of viruses using combinations of tri-n-butyl phosphate and Tween, or sodium cholate / TNBP (tri-n-butyl phosphate) and other buffers, detergents and / or surfactants, but requires the use of high concentrations of auxiliary agents such as saccharose and also heat inactivation in the range of 55° C. to 67° C. which can denature certain proteins and lead to degradation resulting in loss of product.

Louis, Mo., USA) have been used to inactivate viruses, but present problems with high amounts of waste product when used on an industrial scale.

Additionally, some therapeutic proteins are inactivated by TRITON® X-100 and, thus, this method for virus inactivation is not optimal for many protein products.

However, arginine inactivation of T2L was increasingly ineffective at concentrations of above 0.4 M. Kozloff et al. also observed that arginine did not inactivate T-odd strains of bacteriophage.

However, at more neutral pH levels (i.e., pH 5.0-pH 7.0), Yamasaki et al. found arginine to be ineffective at inactivating these viruses.

Yamasaki et al. also found that arginine was ineffective at inactivating non-enveloped polio virus.

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