Selective IL-6 Trans-Signalling Inhibitor With gp130-Fc Dimer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing IL-6 trans-signalling inhibitors have limitations in binding affinity, immunogenic potential, and toxicity, and often cause side effects such as decreased neutrophil and platelet counts and lower levels of C-reactive protein.
Innovation Solution
A polypeptide dimer comprising two monomers with at least 90% sequence identity to SEQ ID NO: 1, which selectively inhibits IL-6 trans-signalling without interfering with classic signalling, administered at doses of 60 mg to 3 g, is developed to treat inflammatory diseases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing IL-6 trans-signalling inhibitors are used, then IL-6 trans-signalling is inhibited, but binding affinity and inhibitory activity are insufficient
Solution Approach 1:
The patent uses a composite structure combining the extracellular domain of human gp130 (which provides high affinity binding to the IL-6/sIL-6R complex) with the Fc region of human IgG1 (which provides dimerization capability and extends half-life). This composite gp130-Fc dimer structure achieves superior inhibitory activity compared to natural sgp130 alone, while maintaining a biologically reasonable molecular complexity.
2Object-affected harmful factors
If IL-6 trans-signalling is inhibited, then chronic inflammation is treated, but neutrophil and platelet counts decrease
Solution Approach 1:
The gp130-Fc dimer exhibits selective inhibition of IL-6 trans-signalling while sparing classic IL-6 signalling. This local quality differentiation allows the drug to target specifically the pathological trans-signalling pathway involved in chronic inflammation, while preserving the classic signalling pathway that maintains normal hematopoiesis and acute phase responses, thus avoiding decreases in neutrophil and platelet counts.
Solution Approach 2:
Instead of blocking IL-6 from binding to both membrane-bound IL-6R and soluble sIL-6R (as traditional antibodies do), the gp130-Fc dimer works by binding to the IL-6/sIL-6R complex and preventing it from engaging with gp130. This inverted mechanism selectively interrupts trans-signalling while leaving classic signalling intact, thereby treating inflammation without causing hematological side effects.
3Reliability
If IL-6 trans-signalling inhibitor is administered, then disease-promoting T-cell populations are prevented from apoptosis, but immunogenic potential and toxicity increase
Solution Approach 1:
The gp130-Fc dimer utilizes parameter changes in its molecular structure - specifically, the fusion of gp130 extracellular domain with Fc region and the resulting dimerization - to achieve high affinity binding (KD in low nM range) and extended half-life (approximately 2 days). These parameter optimizations enhance therapeutic efficacy while the human sequence identity (≥90%) maintains low immunogenicity, resolving the contradiction between efficacy and safety.
4Reliability
If sgp130 is used as trans-signalling inhibitor, then IL-6 trans-signalling is blocked, but binding affinity is low
Solution Approach 1:
The gp130-Fc dimer combines the IL-6/sIL-6R binding domain of gp130 with the Fc region that provides dimerization and FcRn-mediated recycling. This composite structure achieves both high binding affinity (through the gp130 extracellular domain) and extended half-life (through dimerization and FcRn interaction), overcoming the limitations of monomeric sgp130.
Solution Approach 2:
The patent merges two functional elements: the IL-6/sIL-6R complex-binding capability of gp130 extracellular domain and the half-life extending capability of Fc dimerization. This merging creates a single molecule that simultaneously achieves high affinity binding and prolonged circulation, with the dimer structure providing both structural stability and extended pharmacokinetics.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A selective IL-6-trans-signalling inhibitor can be used to treat a variety of IL-6-mediated conditions, including inflammatory diseases and cancer. The inhibitor can safely be administered to humans at a variety of doses. Moreover, the inhibitor lessens deleterious effects associated with other IL-6 inhibitors such as lowering neutrophil counts, platelet counts and levels of C-reactive protein.