Stabilized IGF Polypeptides Preventing Serum Protease Cleavage

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Solution Overview

Problem

Insulin-like growth factors (IGFs) such as IGF-1 and IGF-2 are quickly degraded by endogenous proteases in the serum, making them poor drug candidates, and existing strategies to stabilize them are ineffective.

Innovation Solution

Modifying the precursor IGF proteins by mutating or deleting specific amino acids, such as arginine or serine, to prevent cleavage of the E-peptide, and incorporating modifications like N-linked glycosylation or pegylation to enhance stability and affinity for the IGF-1 receptor.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If IGF-1 or IGF-2 is used as a drug candidate, then the desired therapeutic effect is achieved, but the protein is quickly degraded by endogenous proteases in the serum

Engineering Contradiction:
Improvetherapeutic effectivenessVSAvoidprotein stability in serum
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The invention extracts and removes the problematic E-peptide sequence from the IGF-1 or IGF-2 protein structure. By deleting or mutating the E-peptide (which contains the protease cleavage site), the patent eliminates the vulnerability that causes rapid degradation, thereby resolving the contradiction between therapeutic effectiveness and serum stability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention changes the amino acid sequence parameter of the IGF protein by deleting or mutating specific residues (such as arginine at position 1 or serine/aspartic acid at position 2 of the E-peptide). This parameter change prevents protease recognition and cleavage, transforming the protein from an unstable, rapidly degraded form to a stable, serum-resistant therapeutic candidate.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the E-peptide is cleaved from the precursor protein, then the mature bioactive IGF-1 or IGF-2 is produced, but the protein is rapidly degraded by proteases

Engineering Contradiction:
ImprovebioactivityVSAvoidhalf-life in serum
Core Design Contradiction:
ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The invention extracts the harmful E-peptide component that enables rapid degradation. By removing or mutating the E-peptide sequence, the patent maintains the bioactive IGF-1 or IGF-2 core while eliminating the degradation pathway, thereby extending the protein's half-life in serum without compromising its therapeutic activity.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention performs preliminary modification of the precursor protein structure before it enters the serum environment. By pre-deleting or mutating the E-peptide cleavage sites in the precursor form, the protein is prepared in advance to resist protease degradation, thereby extending its duration of action in the bloodstream while maintaining bioactivity.

Inventive Principle:
Principle #10Preliminary action

3Stability of the object's composition

If modifications are made to prevent E-peptide cleavage, then serum stability is improved, but the protein must be engineered with specific mutations or deletions

Engineering Contradiction:
Improveserum stabilityVSAvoidprotein engineering complexity
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The invention simplifies the protein engineering process by extracting only the essential problematic element (the E-peptide) rather than requiring complex multi-site mutations. By deleting or mutating just the E-peptide region, the patent achieves serum stability with minimal engineering complexity, making the therapeutic development more feasible.

Inventive Principle:
Principle #2Taking out (Extraction)

Data Source

PatentEP2032155B1Stabilized insulin-like growth factor polypeptides
Publication Date: 2014.12.24 NOVARTIS AG
  • EP2032155B1 patent drawingFigure 1A~1C
  • EP2032155B1 patent drawingFigure 2A~2B
  • EP2032155B1 patent drawingFigure 2C~2D

AI summary

The invention relates to stabilized polypeptides having an IGF-1 or IGF-2 sequence and an E-peptide sequence, where the natural physiological cleavage of the E-peptide from the IGF is prevented.