Enhanced Polyethylene Glycol-Linker-Drug Conjugate with Improved Stability, Solubility, and Bioavailability

Publication ID: 24-11857635_0006_PTD
Published: October 28, 2025
Category:Direct Improvements & Enhancements

Legal Citation

pr1or.art Inc., “Enhanced Polyethylene Glycol-Linker-Drug Conjugate with Improved Stability, Solubility, and Bioavailability,” Published Technical Disclosure No. 24-11857635_0006_PTD, Published October 28, 2025, available at https://archive.pr1or.art/24-11857635_0006_PTD
This technical disclosure describes improvements that would be readily apparent to a Person Having Ordinary Skill In The Art (PHOSITA) when considered in combination with the foundational architecture disclosed in U.S. Patent No. 11,857,635.

Summary of the Inventive Concept

The present disclosure relates to an improved polyethylene glycol-linker-drug conjugate, comprising a novel linker compound that enhances the stability, solubility, and bioavailability of the conjugate, and its preparation, pharmaceutical composition, and application.

Background and Problem Solved

The original patent disclosed a polyethylene glycol-linker-drug conjugate, which had limitations in terms of stability, solubility, and bioavailability. The present inventive concept addresses these limitations by introducing a novel linker compound that reduces the immunogenicity of the conjugate, improves its pharmacokinetics, and enhances its bioavailability.

Detailed Description of the Inventive Concept

The novel linker compound X is designed to enhance the stability and solubility of the conjugate, and is synthesized using a click chemistry approach. The linker compound L is modified to reduce the immunogenicity of the conjugate, and the drug moiety D is a protein or polypeptide drug. The pharmaceutical composition comprising the conjugate has improved pharmacokinetics and bioavailability, and the system for delivering the conjugate targets specific cells or tissues, resulting in improved efficacy and reduced side effects.

Novelty and Inventive Step

The novelty of the present inventive concept lies in the introduction of a novel linker compound X that reduces the immunogenicity of the conjugate, improves its pharmacokinetics, and enhances its bioavailability. The inventive step is the combination of the novel linker compound with the polyethylene glycol-linker-drug conjugate, resulting in a conjugate with improved stability, solubility, and bioavailability.

Alternative Embodiments and Variations

Alternative embodiments of the inventive concept include varying the structure of the linker compound X, modifying the drug moiety D, or using different polyethylene glycol residues. Variations of the pharmaceutical composition and system for delivering the conjugate could also be explored.

Potential Commercial Applications and Market

The enhanced polyethylene glycol-linker-drug conjugate has potential commercial applications in the pharmaceutical industry, particularly in the development of targeted therapies for various diseases. The market for such conjugates is expected to grow, driven by the need for more effective and safer treatments.

CPC Classifications

SectionClassGroup
A A61 A61K47/60
A A61 A61K31/704
A A61 A61P35/00

Field of Art

Pharmaceutical biotechnology, specifically drug delivery systems involving polyethylene glycol (PEG) conjugates, with expertise in chemical modification of therapeutic molecules and drug delivery strategies

Person of Ordinary Skill (PHOSITA) Profile

A skilled practitioner with advanced degrees in chemistry or pharmaceutical sciences, familiar with polymer chemistry, conjugation techniques, and drug delivery system design, capable of understanding complex molecular modifications and their potential impacts on drug performance

Obviousness Rationale

A person of ordinary skill would recognize that the PTD represents predictable variations on the source patent's core PEG-linker-drug conjugate technology. The disclosed modifications of linker compounds, click chemistry synthesis, and targeted delivery are logical extensions of existing pharmaceutical conjugation strategies. The technical improvements in stability, solubility, and bioavailability represent incremental advancements that would be expected through routine optimization by a skilled practitioner.

Obvious Combinations & Variations

Source Patent Element
Polyethylene glycol-linker-drug conjugate with variable linking groups
PTD Variation
Introduction of novel linker compound X with modified chemical structure to reduce immunogenicity
Obviousness Reasoning
Modifying linker structures to improve drug conjugate properties is a known technique in pharmaceutical chemistry, representing a predictable variation within the existing technological framework
Source Patent Element
Drug conjugate with potential protein/polypeptide drug targets
PTD Variation
Specific targeting of protein drugs using modified linker to enhance bioavailability
Obviousness Reasoning
Optimizing drug delivery for specific molecular classes is a standard approach in pharmaceutical design, involving routine experimentation with known conjugation techniques
Source Patent Element
Generic PEG-linker conjugation approach
PTD Variation
Click chemistry synthesis method for creating more stable and soluble conjugates
Obviousness Reasoning
Applying modern synthetic techniques like click chemistry to improve existing conjugation methods represents an obvious technological progression for a skilled practitioner
Source Patent Element
General drug delivery conjugate concept
PTD Variation
Targeted delivery system designed to improve cellular specificity and reduce side effects
Obviousness Reasoning
Developing more precise drug delivery mechanisms is a predictable evolution in pharmaceutical technology, involving known strategies of molecular modification
35 U.S.C. § 103 Summary: Based on the teachings of US Patent 11857635 and the published technical disclosure, a person of ordinary skill in the art would find the claimed variations in polyethylene glycol-linker-drug conjugate technology to be obvious and lacking inventive step. The incremental improvements in linker design, synthesis methodology, and targeted delivery represent predictable extensions of existing pharmaceutical conjugation strategies, thus rendering potential patent claims obvious under 35 U.S.C. ยง 103.

Original Patent Information

Patent NumberUS 11,857,635
TitleLinker compound, polyethylene glycol-linker conjugate and derivative thereof and polyethylene glycol-linker-drug conjugate
Assignee(s)JenKem Technology Co., Ltd. (Tianjin)