Gosuranemab scFv-Transferrin Fusion With Cleavable Intracellular Release

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Many antibodies face challenges in crossing biological barriers such as the blood-brain barrier and blood-eye barrier, and entering cancerous cells due to their size and lack of specific targeting mechanisms, limiting their efficacy and application in certain diseases.

Innovation Solution

A single-chain variable fragment (scFv) is designed to bind with the N-methyl lobe of the transferrin protein, utilizing transferrin receptor-mediated endocytosis to enhance cellular uptake, and incorporating cleavable linkers that respond to specific cellular environments for targeted delivery and release.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If whole antibodies are used for therapy, then effector functions and half-life are improved, but penetration across biological barriers is reduced

Engineering Contradiction:
Improvetherapeutic efficacyVSAvoidmolecular size
Core Design Contradiction:
ReliabilityVSLength of moving object

Solution Approach 1:

The antibody is segmented into its functional components: the scFv region retains antigen-binding capability while the Fc region is removed. This segmentation allows the therapeutic agent to penetrate biological barriers more effectively while maintaining target recognition. The scFv fragment (approximately 25-30 kDa) is small enough to cross the blood-brain barrier and other physiological barriers that would block whole antibodies (150 kDa).

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Transferrin or its N-methyl lobe is used as an intermediary to facilitate the transport of scFv across the blood-brain barrier. The transferrin-scFv conjugate exploits the transferrin receptor-mediated transcytosis pathway to deliver the therapeutic agent into the brain, solving the penetration problem without requiring the full antibody structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Length of moving object

If scFv is used to improve barrier penetration, then transcytosis is enhanced, but effector functions are lost

Engineering Contradiction:
Improvemolecular sizeVSAvoidimmune effector functions
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

The Fc region, which mediates effector functions, is extracted from the whole antibody structure. The resulting scFv fragment retains antigen-binding capability but lacks Fc-mediated immune effector functions. This extraction allows the molecule to penetrate barriers effectively while the loss of effector functions is compensated by alternative delivery mechanisms.

Inventive Principle:
Principle #2Taking out (Extraction)

3Stability of the object's composition

If non-cleavable linker is used to stabilize scFv-transferrin conjugate, then structural stability is improved, but controlled release in target cells is reduced

Engineering Contradiction:
Improveconjugate stabilityVSAvoidtargeted release capability
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The linker connecting scFv to transferrin is designed to be dynamically responsive to the cellular environment. Cleavable linkers (such as disulfide bonds or peptide sequences) remain stable in circulation but are cleaved by specific intracellular conditions (reducing environment or proteases), enabling controlled release of scFv inside target cells. This dynamic behavior provides both stability during transport and adaptability for targeted release.

Inventive Principle:
Principle #15Dynamics

4Length of moving object

If antibody size is reduced to enhance tissue penetration, then delivery to target sites is improved, but off-target effects increase

Engineering Contradiction:
Improvemolecular sizeVSAvoidoff-target effects
Core Design Contradiction:
Length of moving objectVSObject-affected harmful factors

Solution Approach 1:

Transferrin acts as an intermediary that provides targeted delivery to transferrin receptor-expressing cells. The scFv-transferrin conjugate is selectively taken up by cells expressing high levels of transferrin receptors (such as cancer cells or brain cells), thereby improving tissue penetration while reducing off-target effects through receptor-mediated specificity.

Inventive Principle:
Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The scFv-conjugate achieves enhanced penetration across biological barriers, improves therapeutic efficacy by reducing off-target effects, and ensures controlled release within target cells, thereby increasing the effectiveness of antibody therapy.

Implementation Method 1

A single-chain variable fragment (scFv) is designed to bind with the N-methyl lobe of the transferrin protein, utilizing transferrin receptor-mediated endocytosis to enhance cellular uptake

Methodology Applied
Scientific EffectTransferrin receptor-mediated endocytosis:

Implementation Method 2

incorporating cleavable linkers that respond to specific cellular environments for targeted delivery and release

Methodology Applied
Scientific EffectCleavable linker degradation:

Data Source

PatentUS20260042826A1Single-chain gosuranemab antibody-transferrin fusion protein for enhanced efficacy and indications
Publication Date: 2026.02.12 RNA THERAPEUTICS INC

AI summary

The efficacy and indication of gosuranemab do not depend on the Fc region and are subject to transit across cell walls. They can be expanded by using their scFvs conjugated with N-methyl lobe of transferrin protein connected with an environment-sensitive cleavable linker to prevent exocytosis of the scFv yielding high exposure inside body cells such as in the brain, eye, and cancer cells that overexpress transferrin receptors.