Use of short-acting embolic agents in reducing drug accumulation in the liver, hepatic clearance and / or hepatotoxicity

Abstract

The present invention discloses the use of a short-term embolic agent in reducing drug accumulation in the liver, hepatic clearance and / or liver toxicity. The present invention provides the use of a short-term embolic agent in the manufacture of a medical composition for: (a) temporarily embolizing blood vessels supplying the liver; and (b) reducing the accumulation of a drug subsequently or concurrently administered intravenously in the liver. The strategy aims to minimize the exposure of a drug (such as LNP) to the liver by temporarily blocking the blood supply to the liver via the portal vein and / or arteries. The present invention significantly reduces the non-specific accumulation of a drug in the liver by temporarily blocking the portal vein, arterial and / or their branch blood flow, thereby greatly reducing the opportunity for the drug to enter the liver from a hemodynamic root.

Description

Technical Field

[0001] This invention belongs to the field of biomedical technology, specifically relating to the application of a short-term embolization agent in reducing drug accumulation in the liver, liver clearance and / or hepatotoxicity. Background Technology

[0002] The information disclosed in this background section is intended only to enhance some understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art.

[0003] The liver is the largest organ of the mononuclear phagocyte system (MPS) or reticuloendothelial system (RES). Many drugs (including nanomedicines) tend to accumulate in or be cleared by the liver after intravenous administration due to the high blood flow to the liver, the large number of phagocytes (Kupffer cells), and the slow blood flow after entering the liver. This phenomenon is considered a major obstacle to clinical translation. To address this issue, researchers have proposed various methods, including temporary capsules of the hepatic sinusoids, forced removal of red blood cells, disabling the uptake capacity of macrophages, saturating Kupffer cells with sufficient nanoparticles, and removing cholesterol from LNP compositions. These approaches, while modifying the hepatic uptake mechanism, cannot maximally inhibit hepatic accumulation of drugs.

[0004] The liver's dual blood supply (75% from the portal vein and 25% from the hepatic artery) provides functional redundancy but also acts as a "trap" for drug accumulation. Portal vein embolization / arterial embolization is a simple and commonly used clinical technique that primarily involves blocking branches of the portal vein / artery to induce proliferation of the remaining liver lobe or cause insufficient blood supply to the branches, leading to tumor necrosis, before hepatectomy. The most commonly used embolization materials include polyvinyl alcohol (PVA) and microcoils. Embolization time generally exceeds 4 weeks. Since this invention aims to reduce drug accumulation in the liver, only a short-term blockage of hepatic blood supply is needed; therefore, a short-term embolization agent is required. Clinical embolization is performed preoperatively to induce proliferation of the remaining liver lobe or cause insufficient blood supply to the branches, leading to tumor necrosis; therefore, the embolization time is relatively long, and only the branches of the portal vein / artery are embolized. Summary of the Invention

[0005] Based on the above analysis, this invention proposes an innovative strategy, transient total portal vein embolization (TTPVE) / arterial embolization, which involves total or partial embolization of the portal vein or artery using a short-term embolic agent (such as starch microspheres) before injection of a drug (such as LNP, doxorubicin, etc.). This strategy aims to minimize the possibility of drug exposure to the liver by temporarily blocking the blood supply to the liver via the portal vein or artery. Considering that the systemic distribution of most drugs is completed within a short period of time (hours or even minutes) after injection, transient total portal vein / arterial embolization helps alleviate the problem of hepatic accumulation without causing liver damage (because the embolization time is very short). This "physical shielding" approach bypasses the complexities associated with in vivo or drug modification, focusing instead on the fundamental hemodynamic mechanisms of hepatic accumulation. This strategy is characterized by its simplicity, directness, and effectiveness, representing an innovative and noteworthy approach in the field.

[0006] The technical solution adopted in this invention is as follows: In a first aspect of the invention, there is provided the use of a short-term embolic agent in the preparation of a medical composition, said medical composition being used for: (a) Temporary embolization of the blood vessels supplying the liver; and (b) Reduce the accumulation of drugs subsequently or simultaneously administered intravenously in the liver.

[0007] The medical composition described in this invention can be formulated from a short-term embolizing agent and a dispersion medium (such as physiological saline) into a suspension or preparation of the desired concentration.

[0008] In one or more embodiments of the present invention, the reduction further includes reducing the hepatic clearance and / or hepatotoxicity of the drug.

[0009] In one or more embodiments of the present invention, the blood vessels supplying the liver include the portal vein, the hepatic artery and / or their branches.

[0010] In one or more embodiments of the present invention, the temporary embolization is either partial or complete embolization. Complete embolization involves injecting a sufficient amount of embolic agent into a blood vessel (such as the main portal vein) to completely block its lumen, thus completely interrupting blood flow to the liver lobe / segment supplied by that vessel. Partial embolization involves selectively embolizing certain branches (e.g., embolizing only the right portal vein branch) while leaving other branches patent by controlling the dosage, particle size, or injection speed and location of the embolic agent; or by partially blocking the lumen of the main blood vessel, significantly slowing or reducing blood flow to the liver region, but not completely stopping it.

[0011] In one or more embodiments of the present invention, the short-term embolic agent maintains the embolic state in vivo for several minutes to several hours.

[0012] In one or more embodiments of the present invention, the short-term embolic agent is a biodegradable material, such as starch microspheres, gelatin sponge microparticles, autologous blood clots, or other embolic materials that can degrade within hours.

[0013] In one embodiment of the invention, starch microspheres are used for total portal vein embolization to prevent drug accumulation in the liver. Starch microspheres are short-term embolic agents and do not cause prolonged vascular occlusion, thus avoiding disruption of subsequent blood flow.

[0014] In one or more embodiments of the present invention, the drug includes, but is not limited to, nanoparticles, macromolecular drugs, or small molecule drugs.

[0015] In one embodiment of the present invention, the nanoparticles are lipid nanoparticles (LNP); the small molecule drug is doxorubicin.

[0016] In a second aspect of the invention, a medicine box is provided, comprising: The first container contains a short-term embolic agent; In addition, the instructions for use instruct the administration of the short-term embolizing agent to the portal vein and / or hepatic artery of a subject to create a temporary embolism in the subject, thereby reducing the accumulation, clearance and / or hepatotoxicity of subsequently intravenously administered drugs in the liver.

[0017] In one or more embodiments of the present invention, the medicine box further includes: a second container containing the medicine, the medicine including but not limited to nanoparticles, macromolecular drugs or small molecule drugs.

[0018] In one or more embodiments of the present invention, the short-term embolic agent is a biodegradable material, such as starch microspheres, gelatin sponge microparticles, autologous blood clots, or other embolic materials that can degrade within hours.

[0019] Compared with the related technologies known to the inventors, one of the technical solutions of the present invention has the following beneficial effects: (1) By temporarily blocking the blood flow of the portal vein, artery and / or its branches, the chance of drugs entering the liver is greatly reduced from a hemodynamic perspective, thereby significantly reducing their nonspecific accumulation in the liver.

[0020] (2) Because the first-pass clearance effect of the liver is avoided, more drugs are retained in the systemic circulation, thus having more opportunities to accumulate in target tissues (such as tumors), achieving the synergistic effect of "reducing liver and increasing target", laying the foundation for enhancing efficacy.

[0021] (3) Using biodegradable short-acting embolic agents (such as starch microspheres), the embolization time is only a few hours, much shorter than the several weeks of clinical PVE. During this period, irreversible liver tissue ischemia or functional damage will not occur.

[0022] (4) The results of blood biochemical indicators (ALT, AST, TBIL, ALP, BUN, CREA, LDH) and routine blood routine monitoring showed that this strategy only caused a reversible stress response in the early postoperative period due to the surgery itself. All indicators returned to normal in a short period of time and did not cause significant liver, kidney or systemic toxicity.

[0023] (5) Portal vein embolization (PVE) or hepatic artery embolization is a widely used and mature clinical technique in interventional radiology. This invention is an innovative application based on this technique, with a short learning curve for clinicians, making it easy to be accepted and promoted.

[0024] (6) The present invention has a clear logic and is straightforward to operate. It can be achieved through interventional radiology, avoiding the uncertainty and side effects that may be caused by in vivo biological regulation.

[0025] (7) This invention creates a short “therapeutic window” during which the injected drug can maximize its effect on the intended target. This provides a new and efficient paradigm for the combination of drug and interventional therapy, with great potential for clinical translation.

[0026] (8) This invention is applicable to a range of drugs with liver accumulation problems, including small molecule chemotherapy drugs (such as doxorubicin), large molecule biological agents and various nano-drug delivery systems (such as LNP), and has broad application prospects and universality. Attached Figure Description

[0027] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0028] Figure 1 Diagram of TTPVE procedure.

[0029] Figure 2 Portal venography image of TTPVE.

[0030] Figure 3 Results of liver H&E staining, Ki67 / PHH3 staining and TUNEL staining.

[0031] Figure 4 Changes in blood parameters in different treatment groups.

[0032] Figure 5Distribution and quantitative analysis of nanoparticles in various organs.

[0033] Figure 6 Distribution and quantitative analysis of drugs in various organs.

[0034] Figure 7 Tumor volume and weight under different treatments. Detailed Implementation

[0035] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0036] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, and / or combinations thereof.

[0037] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0038] Experimental materials: Starch microspheres were purchased from Hangzhou Xiehe Medical Supplies Co., Ltd.

[0039] Preparation of the lipid phase in lipid nanoparticles (LNP): 2.75 mg DSPC, 1.15 mg PEG2000-DMG, 11.6 μl SM-102, and 4.7 mg cholesterol were dissolved in 1.66 ml anhydrous ethanol, and the lipids were completely dissolved by vortex sonication.

[0040] The aqueous phase is prepared by dissolving the detection reagent in ultrapure water.

[0041] Preparation was performed using a microfluidic mixing method: The lipid and aqueous phase solutions were filtered separately through 0.22 μm filter membranes. The aqueous and lipid phase solutions were drawn into corresponding syringes at a 3:1 volume ratio and fixed to microinjection pumps. The syringes were connected to the inlet of the microfluidic chip via tubing. The flow rates of the two microinjection pumps were set: 1.5 mL / min for the aqueous phase and 0.5 mL / min for the lipid phase. Before starting the microinjection pumps, the outlet of the microfluidic chip was connected to a tubing, and the end of the tubing was placed in an EP tube of appropriate volume. The mixed liquid flowing out of the chip outlet was collected as LNP.

[0042] Example: TTPVE: After anesthetizing mice, an abdominal incision was made in the upper midline of the abdomen to expose the portal vein. To induce portal vein embolization, the portal vein was punctured with a needle, and 0.2 mL of preheated starch microspheres were injected. Figure 1 The sham surgery group underwent all surgical procedures, but received saline injections via the portal vein.

[0043] Feasibility of short-term portal vein thrombosis To verify the success of TTPVE, 0.5 mL of iohexol contrast agent was injected into the portal vein immediately after the procedure via an indwelling needle. Mice were then transferred to an angiography apparatus to image the distribution of the contrast agent, the degree of intrahepatic vascular filling, blood flow direction, and the presence of shunts or obstructions. Results showed that this method can achieve portal vein embolization and restore vascular patency within three hours. Figure 2 .

[0044] Safety of short-term portal vein thrombosis At the end of the experiment, the liver was stained with H&E, Ki67 / PHH3, and TUNEL. The results showed no significant abnormalities in cell necrosis, proliferation, apoptosis, cell structure, or morphology. Therefore, this protocol does not cause liver toxicity. Figure 3 .

[0045] A comprehensive evaluation of various safety indicators in the blood of mice before and after surgery was conducted. Alanine aminotransferase 230 (ALT) and aspartate aminotransferase (AST) levels remained within the normal range, indicating that TTPVE did not cause hepatocellular damage in the mouse model. Total bilirubin (TBIL) and alkaline phosphatase (ALP) concentrations were found to be within the standard range, indicating no structural or functional damage to the hepatobiliary system. Blood urea nitrogen (BUN) and creatinine (CREA) levels were both within the established normal range, indicating no significant impairment of renal function. Lactate dehydrogenase (LDH) levels were within the normal range, indicating that TTPVE did not cause systemic tissue damage. Dynamic monitoring of blood counts showed a significant increase in white blood cell (WBC) and platelet (PLT) counts in both the sham-operated group and the TTPVE group within the first 3 days post-surgery. This phenomenon may be a rapid response of the immune and coagulation systems to surgical trauma and stress. Conversely, in the first 3 days, red blood cell (RBC) count, hemoglobin content, and hematocrit value decreased significantly, possibly due to surgical blood loss, hemodilution, and temporary suppression of bone marrow hematopoiesis during the stress response. From 7 days post-surgery until the end of the experiment, all three blood routine indicators fluctuated within a safe range. Figure 4 These results indicate that the regimen does not cause systemic adverse reactions.

[0046] In vivo distribution of nanoparticles The in vivo biodistribution of tumor-bearing BALB / c mice was evaluated using a tumor-bearing BALB / c mouse model. Mice were treated with IR820 (intravenous injection), LNP@IR820 (intravenous injection), or TTPVE+LNP@IR820 (intravenous injection), respectively. After the experiment, the mice were euthanized, and the tumors, lungs, and major organs (including heart, liver, spleen, lungs, and kidneys) were isolated for imaging examination. In vitro images of the mice and mean fluorescence intensity are shown below. Figure 5 As shown, this strategy can reduce the accumulation of nanoparticles in the liver and promote the infiltration of nanoparticles into tumors.

[0047] Distribution within Dorothy Star The in vivo biodistribution of doxorubicin (DOX) was evaluated using a tumor-bearing BALB / c mouse model. DOX is a widely used broad-spectrum chemotherapeutic drug; mice were treated with either DOX (intravenous injection) or TTPVE+DOX (intravenous injection). After the experiment, mice were euthanized, and tumors, lungs, and major organs (including heart, liver, spleen, lungs, and kidneys) were isolated for imaging examination. In vitro images of mice and mean fluorescence intensity are shown below. Figure 6 As shown, this strategy can reduce drug accumulation in the liver and decrease adverse reactions such as hepatotoxicity.

[0048] This experiment uses a colon cancer model as an example, and CT26 cells (1 × 10⁶ cells per mouse) are injected into the right axilla. 6 A mouse subcutaneous colon cancer model was established. Mice bearing tumors were divided into groups, and on days 7 and 14 post-inoculation, they were injected intravenously with saline and DOX, or injected with DOX after TTPVE. Starting on day 7 post-inoculation, tumor length (L) and short vertical diameter (W) were measured. The tumor volume was calculated using the formula: V = (L × W) 2 () / 2, monitor tumor growth in real time during the experiment, and record tumor weight at the end of the experiment. For example... Figure 7 As shown, the DOX+TTPVE group exhibited the most significant inhibition of tumor growth.

[0049] Although the embodiments described herein use mice as an experimental model, those skilled in the art will understand that the short-term embolization agents, embolization methods, and applicable drugs have similar effects in other mammals (including humans). The dosage, particle size, and other parameters of the short-term embolization agents can be determined through routine experiments for subjects of different body sizes.

[0050] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. The use of a short-term embolizing agent in the preparation of a medical composition, characterized in that, The medical composition is used for: (a) Temporary embolization of the blood vessels supplying the liver; and (b) Reduce the accumulation of drugs subsequently or simultaneously administered intravenously in the liver.

2. The application as described in claim 1, characterized in that, The reduction also includes reducing the hepatic clearance and / or hepatotoxicity of the drug.

3. The application as described in claim 1, characterized in that, The blood vessels supplying the liver include the portal vein, hepatic artery, and / or their branches.

4. The application as described in claim 1, characterized in that, The temporary embolism can be a partial embolism or a complete embolism.

5. The application as described in claim 1, characterized in that, The short-term embolic agent maintains the embolic state in the body for several minutes to several hours; The short-term embolic agent is one of starch microspheres, gelatin sponge microparticles, autologous blood clots, or other embolic materials that can degrade within a few hours.

6. The application as described in claim 1, characterized in that, The drug is one or more of nanoparticles, macromolecular drugs, or small molecule drugs; further, the nanoparticles are lipid nanoparticles (LNPs); and the small molecule drug is doxorubicin.

7. A medicine box, characterized in that it comprises: The first container contains a short-term embolic agent; In addition, the instructions for use instruct the administration of the short-term embolizing agent to the portal vein and / or hepatic artery of a subject to create a temporary embolism in the subject, thereby reducing the accumulation, clearance and / or hepatotoxicity of subsequently intravenously administered drugs in the liver.

8. The medicine box as described in claim 7, characterized in that, The medicine box further includes a second container containing the drug, which is one or more of nanoparticles, macromolecular drugs, or small molecule drugs.

9. The medicine box as described in claim 7, characterized in that, The short-term embolizing agent is a biodegradable material.

10. The medicine box as described in claim 9, characterized in that, The short-term embolic agent is starch microspheres, gelatin sponge microparticles, autologous blood clots, or other embolic materials that can degrade within hours.

Images