Enhancing the effect of therapeutic proteins on the central nervous system

Abstract

The present invention provides a polypeptide therapeutic agent, useful in enzyme replacement therapy, with increased therapeutic benefits for the central nervous system. The invention provides a method of enhancing the effect of a polypeptide or protein on the central nervous system by the attachment of a short acidic amino acid sequence. Specifically the inventors disclose the attachment of a 4-15 acidic amino acid sequence to human β-glucuronidase by construction of a fusion protein. This molecule is useful in the treatment of type VII mucopolysaccharidosis when administered to a patient.

Description

PARENT CASE TEXT [0001] This application claims benefit of priority to a continuation in part of U.S. application Ser. No. 11 / 245,424, filed Oct. 7, 2005, and also a continuation in part of U.S. application Ser. No. 10 / 864,758, filed Jun. 10, 2004. [0002] Sequence Listing [0003] A paper copy of the sequence listing and a computer readable form of the same sequence listing are disclosed in U.S. application Ser. No. 11 / 245,424, filed Oct. 7, 2005 to which this application claims benefit of priority as a continuation in part, and is herein incorporated by reference.GOVERNMENT SUPPORT CLAUSE [0004] This work was supported by the National Institutes of Health grant number GM34182, and International Morquio Organization. U.S. Government has certain rights in this invention.BACKGROUND OF THE INVENTION [0005] 1. Field of the Invention [0006] The present invention relates to endowing therapeutic protein agents with increased in vivo stability and effectiveness on the central nervous system (...

AI Technical Summary

Benefits of technology

[0015] An object of the present invention is a method to increase in vivo stability of a physiologically active peptide or protein by the addition of a short acidic amino acid leader, and thereby increase its therapeutic effects on the CNS for treatment of CNS related disease.

[0016] Previously, the inventors made the unexpected discovery that N-acetylgalactosamine-6-sulfate sulfatase (GALNS), tissue-nonspecific alkaline phosphatase (TNSALP) and GUS with a short amino acidic peptide (AAA) attached to the N-terminus increased targeting and deposition of these enzymes to bone. They further discovered that GALNS and GUS, with this short acidic amino acidic peptide attached possessed improved in vivo stability in the blood. The inventors have now further discovered that AAA-GUS possessed improved functional activity to tissues of the CNS, when administered to a patient with MPS VII.

[0017] The addition of a short amino acidic peptide attached to the N-terminus of GUS or other physiology active proteins possessing CNS therapeutic activity will endow these molecules with enhanced therapeutic benefits for the treatment for patients with CNS disorders. Compared with native physiologically active GUS, the present invention described above provides a physiologically active fusion protein with increased stability in the blood and increased therapeutic effects on the brain when administered to a patient with MPS VII.

[0018] Therefore, an object of this invention is 1) a polypeptide therapeutic agent with increased benefits for the CNS, 2) a method of increasing beneficial effects on the CNS, of a protein or polypeptide possessing CNS therapeutic activity, by attaching a 4-15 acid amino acid leader through chemical modification or genetic engineering of a fusion protein and 3) a method of treatment for patients suffering from CNS related diseases with the afore mentioned preparation.

Problems solved by technology

Meanwhile there is a problem that pharmaceutical preparations of physiologically active proteins like enzymes and peptide hormones are generally made unstable when they are administered to the body, and thus undergo relatively rapid inactivation by, e.g., enzymatic degradation.

No effective remedy is currently available for MPS VII.

Considering its rapid inactivation in the body, however, native GUS is not expected to give any satisfactory effect.

The challenge is to improve joint and brain-related pathology since most of the enzyme-based drugs are delivered to major visceral organs like liver and spleen and only a small amount of enzyme is delivered to bone and brain.

Many lysosomal enzymes have a short half-life when injected into the bloodstream because of rapid clearance in the liver by carbohydrate-recognizing receptors, particularly the mannose receptor that is highly abundant on Kupffer cells.12 Although a part of the enzyme reaches the bone marrow, there is no way to guarantee that the enzyme will reach the brain since the blood brain barrier presents a formidable obstacle.

As a result, current ERT doses not work efficiently on the bone and brain lesions.

Images