Fc-IL2 Variant Combination Therapy for Selective CAR-T Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current CAR-T cell therapies for solid tumors face challenges such as on-target off-tumor toxicity, systemic cytokine release, exhaustion of engineered T cells, and limited persistence, along with suboptimal cell composition and dose-limiting systemic side effects from conventional IL-2 therapy.
Innovation Solution
A combination therapy using recombinant Fc domain-IL2 variant (Fc-IL2v) polypeptides with membrane-anchored antigen binding (MAB) polypeptides, comprising specific amino acid substitutions, to enhance targeted T cell activation and expansion while minimizing systemic toxicity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional IL-2 therapy is used to expand T cells, then T cell numbers increase, but systemic side effects occur due to dose-limiting toxicity
Solution Approach 1:
The patent introduces a membrane-anchored adapter molecule as an intermediary that enables specific binding between engineered CAR-T cells and IL-2. This adapter molecule is expressed only on the surface of engineered T cells, allowing IL-2 to selectively bind and expand only these cells rather than all T cells systemically, thereby reducing off-target side effects while achieving desired expansion
Solution Approach 2:
The invention creates local specificity by anchoring the IL-2 binding site directly to the membrane of engineered T cells via the adapter molecule. This localized expression ensures that IL-2 acts only on cells expressing the adapter (i.e., engineered CAR-T cells), creating a localized effect rather than systemic exposure, thus expanding T cell numbers without proportionally increasing systemic toxicity
2Stability of the object's composition
If ex vivo expansion time is reduced to limit T cell differentiation, then cell composition improves, but production cost and time are saved only if expansion can occur in patients
Solution Approach 1:
The patent enables the T cells themselves to provide the necessary components for their own expansion by expressing the membrane-anchored adapter molecule that binds IL-2. When IL-2 is administered in vivo, the engineered T cells autonomously receive the expansion signal through their surface-bound adapters, eliminating the need for complex ex vivo expansion infrastructure and allowing expansion to occur directly in the patient's body
Solution Approach 2:
The engineered T cells are pre-modified ex vivo to express the membrane-anchored adapter molecule and cytokine receptor. This preliminary engineering step enables them to autonomously respond to IL-2 administration in vivo, allowing the actual expansion to occur in the patient rather than requiring prolonged ex vivo culture, thus preserving stem-like memory phenotype while simplifying production
3Reliability
If CAR-T cells are engineered with high specificity for tumor antigens, then therapeutic activity increases, but on-target off-tumor toxicity occurs due to antigen expression in healthy tissues
Solution Approach 1:
The patent introduces a two-step recognition system where the CAR-T cell first recognizes the tumor antigen through its CAR, then requires binding of IL-2 to the membrane-anchored adapter for full activation. This intermediary adapter layer provides an additional layer of control, allowing activation to occur only when both the antigen is present and IL-2 is administered, thereby reducing unintended activation in healthy tissues while maintaining therapeutic activity against tumors
Solution Approach 2:
The invention creates a dynamic control system where T cell activation is not static but depends on the administration of IL-2. The membrane-anchored adapter allows the system to transition from a continuously active state (which causes toxicity) to a controlled, on-demand activation state. By dynamically controlling when IL-2 is administered, therapeutic activity can be activated only when needed while minimizing off-tumor toxicity during non-therapy periods
Data Source
AI summary
The present invention relates to the combination therapy of recombinant Fc domain-IL-2 variant polypeptides with membrane-anchored antigen binding polypeptides in the prevention or treatment of cancer.