CD25 Aptamer Drug Conjugate for Selective Tumor Treg Depletion

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing cancer immunotherapies face challenges in selectively depleting tumor-infiltrating regulatory T cells (Tregs) without affecting systemic Tregs, leading to autoimmune side effects, due to the high expression of CD25 on both cell types.

Innovation Solution

Development of a CD25-targeting aptamer and its drug conjugate that inhibits IL-2 binding to CD25, specifically depleting tumor-infiltrating Tregs and treating CD25-positive hematologic malignancies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If anti-CD25 antibodies are used to deplete Tregs, then Treg depletion effect is achieved, but autoimmune side effects occur due to systemic Treg depletion

Engineering Contradiction:

ImproveTreg depletion efficacyVSAvoidautoimmune side effects

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by creating a tumor microenvironment-specific aptamer that selectively targets Tregs within the tumor. The aptamer is designed to bind CD25 with high affinity specifically in the tumor context, achieving localized Treg depletion while sparing systemic Tregs. This spatially selective approach resolves the contradiction between effective Treg depletion and avoidance of autoimmune side effects.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent uses an aptamer as an intermediary molecule between the therapeutic goal (Treg depletion) and the target (CD25 on Tregs). This aptamer intermediary provides selective binding to CD25 in the tumor microenvironment, mediating the depletion effect while the shorter half-life of the aptamer compared to antibodies ensures it doesn't persist systemically, thus avoiding autoimmune side effects.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Duration of action of moving object

If aptamers are used instead of antibodies, then half-life is shortened to minimize systemic effect, but binding affinity and specificity must be maintained

Engineering Contradiction:

Improveaptamer half-lifeVSAvoidbinding affinity and specificity

Core Design Contradiction:

Duration of action of moving objectVSReliability

Solution Approach 1:

The patent applies parameter changes by optimizing the aptamer's physical and chemical parameters to achieve the desired balance. The aptamer is designed with specific sequence and structural parameters that enable high-affinity binding to CD25 (pM level), while its inherent shorter half-life compared to antibodies is maintained as a beneficial parameter for minimizing systemic exposure. The aptamer's stability and binding characteristics are tuned through molecular design to resolve the contradiction between short duration and high reliability.

Inventive Principle:

Principle #35Parameter changes

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 aptamer effectively suppresses CD25-positive T cell activation and induces selective depletion of tumor-infiltrating Tregs, minimizing autoimmune side effects and enhancing cancer immunotherapy efficacy.

Implementation Method 1

an aptamer of the present invention specifically binds to CD25 protein, thereby inhibiting binding of IL-2 and CD25 protein

Methodology Applied

Scientific EffectMolecular binding: Adsorption

Data Source

PatentEP4729617A1Aptamer targeting CD25, drug conjugate comprising same, and use thereof

Publication Date: 2026.04.22 APTAMER SCI

Figure 1
Figure 2
Figure 3

AI summary

The present invention relates to an aptamer targeting CD25, a drug conjugate comprising the same, and use thereof