Use of multi-arm polyethylene glycol modifier and application of multi-arm polyethylene glycol modifier in L-asparaginasum modification

Inventors

MA, Bruce Yong • Wang, Jun • WU, Dinglong • Xu, Chunlin • WANG, Yaofang

Assignees

GENSUN INSTITUTE OF BIOMEDICINE Co Ltd • Zonhon Biopharma Institute Inc

Abstract

Methods for use of a multi-arm polyethylene glycol (PEG) modifier in modification of asparaginase. The described multi-arm PEG modifier enhances the subunit interaction of a multimeric protein to maintain the multimeric protein in a polymerized form, thereby improving the stability of the multimeric protein, maintaining the bioactivity of the multimeric protein, and reducing the probability of exposure of the antigen binding site after depolymerization of the subunits, so as to reduce the immunogenicity.

Core Innovation

The invention relates to a multimeric protein modified with a multi-arm polyethylene glycol (PEG). The multi-arm PEG comprises a chain of repeating units having from 2 to 16 activating groups that react with respective amino acid residues of subunits of the multimeric protein, and the activating groups enhance interaction between the subunits such that the multimeric protein modified with the multi-arm PEG has increased stability and reduced immunogenicity as compared with the multimeric protein when modified with a PEG comprising a chain having only 1 of the activating groups.

The described approach is exemplified by modifying L-asparaginase, a multimeric enzyme, with an aldehyde-activated or ester-activated multi-arm PEG, with representative conjugates including 4SCM5K-ASP and 4PALD10K-ASP. The document reports improved uniformity, enhanced thermal and 37°C stability, resistance to PEG detachment, and retained in-vitro enzymatic activity, and compares performance against pegaspargase.

The document also states that the strategy supports reduced immunogenicity and improved in vivo performance for tumor treatment. PEG-modified L-asparaginase is reported to have reduced antibody titers, extended pharmacokinetic half-life (T1/2), and improved anti-tumor efficacy in a tumor model, and the concept is described as being demonstrated across other multimeric enzymes including alkaline phosphatase, urease, and glutamate dehydrogenase.

Claims Coverage

The claims are directed to a multi-arm PEG modification of a multimeric protein using PEG containing 2 to 16 activating groups, with emphasis on increased stability and reduced immunogenicity versus modification with a PEG having only 1 activating group.

The central inventive concept is that PEG architecture with multiple activating groups that react with subunit amino acid residues enhances subunit interaction, yielding increased stability and reduced immunogenicity relative to a PEG containing only one activating group.

Stated Advantages

Documented Applications