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CN-121971645-A - Antibody targeting covalent drug conjugate and preparation method and application thereof

CN121971645ACN 121971645 ACN121971645 ACN 121971645ACN-121971645-A

Abstract

The invention discloses an antibody targeting covalent drug conjugate, a preparation method and application thereof, which consists of a monoclonal antibody, a targeting covalent inhibitor and a reversible covalent arsenic-sulfur bond connector, wherein the monoclonal antibody is connected with the targeting covalent inhibitor through the reversible covalent arsenic-sulfur bond connector, the monoclonal antibody is used for targeting and identifying cells, the targeting covalent inhibitor is used for forming a reversible covalent arsenic-sulfur bond with a target protein so as to inhibit the activity of the target protein, and the reversible covalent arsenic-sulfur bond connector is used as a cleavable part and an electrophilic warhead of the targeting covalent inhibitor. The invention ensures high-efficiency oncoprotein inhibition based on the controllable release of arsenic-sulfhydryl exchange reaction, verifies the intracellular binding activity through fluorescent labeling and signal path experiments, provides a novel linker reference for the design of antibody-drug conjugate, and improves the innovation level of the biopharmaceutical field.

Inventors

  • YAN XIAOWEN
  • ZHAO XINYUE

Assignees

  • 厦门大学

Dates

Publication Date
20260505
Application Date
20260204

Claims (10)

  1. 1. The antibody targeting covalent drug conjugate is characterized by comprising a monoclonal antibody, a targeting covalent inhibitor and a reversible covalent arsenic-sulfur bond connector, wherein the monoclonal antibody is connected with the targeting covalent inhibitor through the reversible covalent arsenic-sulfur bond connector, the monoclonal antibody is used for targeting and identifying cells, the targeting covalent inhibitor is used for forming a reversible covalent arsenic-sulfur bond with a target protein so as to inhibit the activity of the target protein, and the reversible covalent arsenic-sulfur bond connector is used as a cleavable part and an electrophilic warhead of the targeting covalent inhibitor.
  2. 2. The antibody-targeted covalent drug conjugate of claim 1, wherein the monoclonal antibody is CD 19-targeted Loncastuximab or CD 20-targeted Rituximab.
  3. 3. An antibody targeted covalent drug conjugate according to claim 1, wherein the targeted covalent inhibitor is derived from arsenic compound I-As-4 of the formula 。
  4. 4. An antibody-targeted covalent drug conjugate according to claim 1, wherein the reversible covalent arsenic-sulfur bond linker has the structural formula 。
  5. 5. An antibody-targeted covalent drug conjugate according to claim 1, wherein the monoclonal antibody is CD 19-targeted Loncastuximab or CD 20-targeted Rituximab, the targeted covalent inhibitor is derived from arsenic compound I-As-4, and the reversible covalent arsenic-sulfur bond linker has the structural formula 。
  6. 6. An antibody targeted covalent drug conjugate according to any one of claims 1 to 5, characterized in that the drug-to-drug ratio is 3.6-4.5.
  7. 7. The preparation method of the antibody targeting covalent drug conjugate is characterized by comprising the following steps: (1) The intermediate Ibt-LAPEG 4 NHS is synthesized by preparing LANHS active ester from lipoic acid, reacting with amino of NH 2 -(PEG) 4 -COOH, activating carboxyl with NHS to prepare LAPEG 4 NHS active ester, and finally reducing disulfide bond with TCEP to react with arsenic compound I-As-4; (2) And (3) coupling the monoclonal antibody with the intermediate Ibt-LAPEG 4 NHS to obtain the antibody.
  8. 8. The method of claim 7, wherein the monoclonal antibody is CD 19-targeting Loncastuximab or CD 20-targeting Rituximab.
  9. 9. Use of an antibody-targeted covalent drug conjugate according to any one of claims 1 to 6 for the preparation of an anti-tumor drug.
  10. 10. The method according to claim 9, wherein the anti-tumor agent is against B-cell lymphoma.

Description

Antibody targeting covalent drug conjugate and preparation method and application thereof Technical Field The invention belongs to the technical field of biological medicine, and particularly relates to an antibody targeting covalent drug conjugate, and a preparation method and application thereof. Background The targeted covalent inhibitor (Targeted covalent inhibitors, TCIs) is an important compound with pharmacological activity, and the principle of action is to inhibit proteins related to diseases through target recognition and covalent bond formation, so that accurate treatment effect is realized. TCIs the mechanism of action involves two independent steps. Firstly, its high affinity ligand binds reversibly to the target protein, bringing the electrophilic warhead close to the nucleophilic residue on the protein, and then, the electrophilic warhead spontaneously forms a covalent bond with the residue, achieving a powerful protein inhibition. Numerous TCIs drugs have been approved by the U.S. Food and Drug Administration (FDA) for cancer treatment, which drugs exhibit significant efficacy in clinical practice, such as inhibition against specific kinases. However, TCIs cannot directly target tumor cells, and still face challenges such as poor cell specificity. This results in the possibility that the drug will act on normal cells during the course of treatment, producing off-target effects, thereby limiting its anti-tumor efficacy and increasing the risk of side effects. Therefore, targeting small molecules TCIs to cells has become an important research direction to further improve anti-tumor efficacy and reduce side effects. Monoclonal antibodies (Monoclonal Antibody, mabs) are becoming increasingly important in tumor therapy because of their excellent cell targeting and pharmacokinetic properties. Monoclonal antibodies target tumor cells through unique antigen specificity, and have excellent cell targeting ability, extremely low side effects and remarkable clinical effects. Therefore, they have become an important research direction in the biopharmaceutical field. For example, certain mabs specifically recognize receptors on the surface of B-cell lymphoma cells, such as CD19 or CD20, thereby achieving precise localization of tumor cells. However, most monoclonal antibodies have limited cytotoxicity to tumor cells and cannot induce sufficient cell death independently. This makes mAb often limited in efficacy when used alone, failing to meet the therapeutic needs of complex tumor environments. To overcome this limitation, researchers have often used mabs in combination with highly toxic small molecule drug carriers to enhance overall antitumor activity. Based on this, antibody-drug conjugates (anti-drug conjugates, ADCs) were developed aimed at achieving specific cell targeting and high cytotoxicity to tumor cells. The core design of ADCs is to couple monoclonal antibodies to cytotoxic drugs via linkers to form a complex. The antibody part is responsible for recognizing and combining tumor cell surface antigen to promote endocytosis, and the medicine part is released inside cell to kill. This strategy combines the targeting of antibodies with the toxicity of the drug, theoretically enabling precise delivery of the drug to the tumor site, reducing exposure to normal tissues. However, existing ADCs still present significant problems. The broad-spectrum chemotherapeutic medicine with high toxicity is used as a carrier, and can damage normal cells due to lack of protein targeting specificity, thereby causing toxic and side effects. These drugs are often non-selective and, once released in non-target cells, may trigger systemic toxicity such as bone marrow suppression or nerve damage. In addition, the design of linkers for traditional ADCs is also challenging, for example, insufficient stability of the linker may lead to premature extracellular release, or inefficient cleavage resulting in insufficient drug function. These deficiencies limit the clinical utility of ADCs, and despite the many commercial availability of ADCs, side effects from off-target delivery remain a major challenge. To further optimize ADCs, TCIs with high protein targeting was chosen as a drug carrier, hopefully reducing the toxic side effects of off-target release. TCIs can specifically inhibit disease-related proteins, such as Bruton Tyrosine Kinase (BTK), which is a key oncoprotein, and plays an important role in tumors such as B cell lymphomas. By coupling TCIs with a mAb, specific recognition of cancer cells and targeted inhibition of intracellular oncoproteins can potentially be achieved. However, existing research remains in the exploration phase, facing the difficult problem of how to design suitable linkers to ensure extracellular stability and efficient release inside the cells. The linker needs to have controllable cleavage properties, for example, to react under the action of intracellular high concentration reducing agents s