Factor I Gene Therapy for Systemic Complement Control

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Solution Overview

Problem

Current treatments for complement-mediated disorders, such as age-related macular degeneration (AMD), dense deposit disease (DDD), and atypical haemolytic uremic syndrome (aHUS), are limited by the systemic nature of the complement C3b feedback cycle hyperactivity, which cannot be effectively regulated by local administration methods like intravitreal injections, and there is a need for a systemic approach to balance the feedback loop.

Innovation Solution

Gene therapy using a recombinant adeno-associated virus (rAAV) vector to over-express Factor I in the liver, increasing plasma levels of Factor I to regulate the complement C3b feedback cycle systemically, thereby promoting C3b and iC3b breakdown and reducing inflammation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If local administration methods like intravitreal injections are used, then local treatment is achieved, but the systemic nature of the complement C3b feedback cycle hyperactivity cannot be effectively regulated

Engineering Contradiction:
Improvelocal administrationVSAvoidsystemic regulation effectiveness
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent uses Factor I as an intermediary substance to regulate the complement C3b feedback cycle systemically. By administering Factor I (either as recombinant protein or through gene therapy), the treatment mediates the regulatory effect throughout the bloodstream, overcoming the limitation of local administration and achieving systemic control of the hyperactive complement pathway.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the mechanical/local injection method with a biochemical/systemic approach. Instead of relying on physical delivery to the eye, the treatment uses systemic circulation of Factor I to reach the complement pathway regulation sites throughout the body, substituting mechanical local delivery with biochemical systemic distribution.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If gene therapy is used to over-express Factor I in the liver, then plasma levels of Factor I are increased systemically, but the complexity of the treatment increases

Engineering Contradiction:
Improvesystemic regulation effectivenessVSAvoidtreatment complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The gene therapy approach enables the liver to self-produce and secrete Factor I continuously. By delivering the Factor I gene to hepatocytes, the liver cells are transformed into self-sufficient factories that automatically produce and release Factor I into the plasma, eliminating the need for repeated external administrations and simplifying the long-term treatment regimen.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent changes the production parameter of Factor I from endogenous baseline levels to exogenously elevated levels through gene therapy. By introducing additional copies of the Factor I gene or enhancing expression of existing genes, the plasma concentration of Factor I is increased to therapeutic levels, achieving reliable systemic regulation of the complement pathway.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If Factor I levels are increased to regulate the C3b feedback cycle, then C3b and iC3b breakdown is enhanced, but the balance between the feedback and breakdown cycles must be carefully maintained

Engineering Contradiction:
Improvecomplement pathway regulationVSAvoidfeedback loop balance
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent utilizes the natural feedback mechanism of the complement system. By increasing Factor I levels, the system enhances the breakdown of C3b and iC3b, which in turn reduces the substrate available for feedback amplification. This creates a self-regulating system where increased Factor I activity automatically dampens the hyperactive feedback loop, restoring balance without requiring external control mechanisms.

Inventive Principle:
Principle #23Feedback

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 systemic increase in Factor I levels through rAAV-mediated gene therapy rebalances the alternative pathway, effectively reducing disease progression in complement-mediated disorders by enhancing C3b and iC3b degradation, offering a potential cure for conditions like AMD, DDD, and aHUS.

Implementation Method 1

Gene therapy using a recombinant adeno-associated virus (rAAV) vector to over-express Factor I in the liver, increasing plasma levels of Factor I

Methodology Applied
Scientific EffectGene therapy:

Implementation Method 2

recombinant adeno-associated virus (rAAV) vector

Methodology Applied
Scientific EffectViral transduction:

Implementation Method 3

C3b undergoes a structural rearrangement that enables the serine protease precursor Factor B to bind to C3b

Methodology Applied
Scientific EffectProteolysis: Enzyme

Implementation Method 4

over-express Factor I in the liver, increasing plasma levels of Factor I

Methodology Applied
Scientific EffectSecretion:

Data Source

PatentEP3454910B1Treatment of complement-mediated disorders
Publication Date: 2025.11.05 CAMBRIDGE ENTERPRISE LTD
  • EP3454910B1 patent drawingFigure 1
  • EP3454910B1 patent drawingFigure 2~6
  • EP3454910B1 patent drawingFigure 3

AI summary

Methods of treatment of complement-mediated disorders, in particular disorders associated with over-activity of the complement C3b feedback cycle (for example, age-related macular degeneration (AMD)), using gene therapy is described. According to the methods, levels of complement Factor I are elevated by administration of a recombinant viral vector encoding Factor I such that a therapeutically effective amount of the encoded Factor I is expressed from the vector in the subject. Recombinant viral vectors encoding Factor I, recombinant virus particles encapsidating the vectors, and their use in the methods of treatment, is also described.