Suspension containing radioactive microspheres, and preparation method therefor and use thereof

Abstract

A suspension containing radioactive microspheres. The radioactive microsphere comprises a resin microsphere and a radionuclide loaded on the resin microsphere, wherein the average particle size of the radioactive microsphere is 25 μm to 40 μm. By means of controlling the proportion of non-spherical microspheres in the radioactive microspheres to be within 5%, the distribution density of the microspheres at a tumor part is increased, the effect of killing tumors is improved, and the treatment safety is improved.

Description

Suspension containing radioactive microspheres and its preparation method and application

[0001] This application claims priority to Chinese Patent Application No. 2023108208986, filed on July 6, 2023. This application incorporates the entirety of the aforementioned Chinese Patent Application. Technical Field

[0002] The present application relates to the medical field, and in particular to a suspension containing radioactive microspheres, a preparation method thereof, and an application thereof. Background Art

[0003] There are currently multiple treatment options for malignant tumors, including chemotherapy, radiotherapy, interventional therapy, and biological immunotherapy. Since most patients are diagnosed with cancer in the late stages, excluding surgical treatment options and becoming insensitive to chemotherapy drugs after multiple rounds of chemotherapy, radiotherapy has become a key treatment option for certain cancers.

[0004] Radioactive microsphere therapy is a method of preparing radioactive materials into microspheres of regular size, which are then injected into the arterial blood supply of the target organ and emit large doses of high-energy radiation to kill tumor tissue. Due to the limited penetration depth of radiation tissue, it can also protect nearby healthy tissues. Radioactive microspheres mainly consist of a carrier and a radionuclide loaded on the carrier. Currently, the radionuclides used in radioactive microspheres include yttrium [ 90 Y], phosphorus [ 32 P], iodine [ 131 I], iodine[ 125 I], technetium[ 99m Tc], rhenium [ 188 Re], holmium 166 Ho et al. Resin microspheres as carriers have a density close to that of blood and are not easy to settle. They have been used in clinical practice, especially in the treatment of hepatocellular carcinoma (HCC).

[0005] Although radioactive microsphere therapy causes less damage to the patient's normal tissues, some patients still experience adverse reactions after use. Existing radioactive microspheres are more effective for small tumors with a volume of <10cc, but the distribution of radioactive microspheres within the boundaries of large tumors with a volume greater than >10cc, especially deep in the tumor, needs to be improved.

[0006] Summary of the Invention

[0007] In view of this, the present application provides a suspension of radioactive microspheres, a preparation method thereof, and an application thereof, aiming to improve the adverse reactions caused by existing radioactive microspheres and the problem that the therapeutic effect needs to be improved.

[0008] In a first aspect, the present application provides a suspension containing radioactive microspheres, wherein the radioactive microspheres include resin microspheres and radioactive nuclides loaded on the resin microspheres, the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the non-spherical ratio of the radioactive microspheres is within 5%.

[0009] Optionally, the non-spherical ratio refers to the ratio of the number of non-spherical radioactive microspheres to the total radioactive microspheres in the suspension, and the non-spherical radioactive microspheres refer to radioactive microspheres with a minimum radius less than 75% of the radius of the original microspheres.

[0010] Optionally, based on the number of the radioactive microspheres, in the suspension, the number of radioactive microspheres ranging from 20 μm to 60 μm accounts for more than 85%.

[0011] Optionally, the material of the resin microspheres is selected from at least one of cross-linked polystyrene resin, cross-linked polyethylene resin or cross-linked polydivinylbenzene resin.

[0012] Optionally, the resin microspheres are any one of resin microspheres with sulfonic acid groups, resin microspheres with nitro groups, and carbonized resin microspheres.

[0013] Optionally, the radionuclide is selected from at least one isotope of yttrium, lutetium, indium, holmium, samarium, iodine, phosphorus, iridium or rhenium.

[0014] Optionally, in the suspension, the non-spherical ratio of the radioactive microspheres is within 2%.

[0015] Optionally, the material of the resin microspheres is selected from polystyrene resin cross-linked with divinylbenzene and having sulfonic acid groups. Optionally, the radioactive nuclide is selected from yttrium [ 90 Y]

[0016] Optionally, each 1 mL of suspension contains yttrium [ 90 Y] activity is 300~700MBq.

[0017] Optionally, the suspension further contains water for injection.

[0018] In a second aspect, the present invention provides a suspension containing radioactive microspheres, wherein the radioactive microspheres include resin microspheres and radionuclides loaded on the resin microspheres, wherein the material of the resin microspheres includes at least one of polystyrene, polyethylene or polydivinylbenzene, or a cross-linked polymer thereof, and the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the asphericity ratio is within 5%.

[0019] Optionally, the non-spherical ratio refers to the ratio of the number of non-spherical radioactive microspheres to the total radioactive microspheres in the suspension, and the non-spherical radioactive microspheres refer to radioactive microspheres with a minimum radius less than 75% of the radius of the original microspheres.

[0020] Optionally, based on the number of the radioactive microspheres, in the suspension, the number of radioactive microspheres ranging from 20 μm to 60 μm accounts for greater than 85%; and / or the non-spherical ratio of the radioactive microspheres is within 2%; and / or the material of the resin microspheres is selected from cross-linked polystyrene microspheres with a cross-linking degree of 2% to 10%.

[0021] Optionally, the resin microspheres are sulfonated, nitrated or carbonized resin microspheres.

[0022] Optionally, the radionuclide is selected from at least one isotope of yttrium, lutetium, indium, holmium, samarium, iodine, phosphorus, iridium or rhenium.

[0023] Optionally, the radionuclide is selected from yttrium [ 90 Y], the material of the resin microspheres is selected from sulfonated polystyrene partially cross-linked with divinylbenzene, and the suspension also contains water for injection, each 1 mL of yttrium [ 90 Y] activity is 300~700MBq.

[0024] Optionally, the material of the resin microspheres is selected from polystyrene resin cross-linked with divinylbenzene and having sulfonic acid groups.

[0025] Optionally, the suspension further contains water for injection.

[0026] Optionally, the radionuclide is selected from yttrium [ 90 Y], each 1 mL of the suspension contains yttrium [90 Y] activity is 300~700MBq.

[0027] In a third aspect, the present invention provides a method for preparing a suspension containing radioactive microspheres, the method comprising: mixing resin microspheres and a radionuclide compound in a solution, and reacting to obtain the suspension containing the radioactive microspheres; the material of the resin microspheres comprises at least one of polystyrene, polyethylene, or polydivinylbenzene, or a cross-linked polymer thereof, the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the asphericity ratio is within 5%.

[0028] Optionally, the resin microspheres are subjected to sulfonation, nitration or carbonization before being mixed with the radionuclide compound.

[0029] In a fourth aspect, the present application provides a method for preparing a suspension, comprising: mixing resin microspheres and a radioactive nuclide compound in a solution, and reacting to obtain the suspension containing the radioactive microspheres; the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the asphericity ratio is within 5%.

[0030] Optionally, the resin microspheres are subjected to sulfonation, nitration or carbonization before being mixed with the radionuclide compound.

[0031] In a fifth aspect, the present application provides use of the suspension described in the first aspect or the suspension prepared by the method described in the second aspect in the preparation of a drug for treating tumors.

[0032] Optionally, the tumor is primary or secondary liver cancer.

[0033] In a sixth aspect, the present application provides a method for treating tumors, comprising: administering the suspension described in the first aspect or the suspension prepared by the method described in the second aspect to a tumor patient. Beneficial effects:

[0034] The present application provides a suspension of radioactive microspheres, which include resin microspheres and radionuclides loaded on the resin microspheres. The average particle size of the radioactive microspheres is 25 to 40 μm. By controlling the non-spherical ratio of the radioactive microspheres to within 5%, the distribution density of the microspheres in the tumor area is increased, the therapeutic effect is improved, the incidence of adverse reactions is reduced, and safety is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments.

[0036] FIG1 is a diagram showing the minimum radius (R min ) and the radius (R) of the original microsphere. In FIG1 , A is an example of a spherical microsphere, and B, C, and D each represent an example of a non-spherical microsphere.

[0037] FIG2 is a microscope photograph of non-spherical radioactive polystyrene microspheres in an example of the present application.

[0038] FIG3 is a schematic diagram of the implantation position of the test article or the control article in the embodiment of the present application. DETAILED DESCRIPTION

[0039] In order to make the technical problems, technical solutions, and technical effects to be solved by the present invention more clearly understood, the present invention will be further described in detail below with reference to specific embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.

[0040] The radioactive microspheres in the prior art have defects such as adverse reactions found during treatment and the need to improve the treatment effect, such as radioactive polystyrene microspheres prepared by commercially available sulfonated polystyrene microspheres or radioactive polystyrene microspheres or carbon microspheres prepared by the methods provided in CN202211592412X, CN2022116010239 and CN2022116017505.

[0041] The inventors unexpectedly discovered that the non-sphericity ratio of radioactive microspheres significantly affects their therapeutic efficacy and the adverse reactions experienced by subjects after implantation. Studies have shown that the non-sphericity ratio of microspheres is a key factor influencing their distribution density in the body, ultimately affecting both efficacy and safety. Controlling the non-sphericity ratio of a suspension containing radioactive microspheres to less than 5% not only increases the distribution density of the microspheres within the tumor, indicating a better tumor-killing effect, but also significantly reduces irritation and inflammation, thereby lowering the incidence of adverse reactions such as fever, pain, and liver damage. The radioactive microspheres produced by prior art methods generally have a relatively high non-sphericity ratio, typically exceeding 10%. Even though the probability of non-spheric microspheres produced during the sulfonation process can be relatively reduced by controlling the stirring speed, the non-sphericity ratio of the final radioactive microspheres still exceeds 10%. Prior art has not explored the non-sphericity ratio of suspensions containing radioactive microspheres.

[0042] In view of this, the present invention first provides a suspension containing radioactive microspheres, which is used for radiotherapy of malignant tumors. The radioactive microspheres include resin microspheres and radionuclides loaded on the resin microspheres. The average particle size of the radioactive microspheres is 25 to 40 μm (micrometers), and the non-sphericity ratio of the radioactive microspheres is within 5%. Compared with the prior art, by controlling the non-sphericity ratio of the radioactive microspheres within this range, not only the therapeutic effect is improved, but also the safety can be improved.

[0043] In this article, "non-spherical ratio" refers to the ratio of the number of non-spherical microspheres to the total microspheres in the suspension. Non-spherical microspheres are microspheres with a minimum radius less than 75% of the radius of the original microspheres. Correspondingly, "spherical ratio" refers to the ratio of the number of spherical microspheres to the total microspheres in a certain amount of suspension, and the spherical microspheres are microspheres with a minimum radius (R min ) is higher than the original microsphere radius (R) 75% of the microsphere. Rmin It refers to the shortest distance from the center of the circle to the edge under the orthographic projection. The center of the circle refers to the center of the two points on the microsphere with the longest straight-line distance under the orthographic projection (if the distance from the center of the circle to any point on the edge of the microsphere is equal, non-spherical microspheres are not counted); R refers to the average radius of the microspheres. The average radius is relative to the average diameter. The average diameter refers to the average particle size of all microspheres in the suspension. The average radius is half of the average particle size. It can be understood that the original microsphere is a standard round microsphere with a diameter of the average particle size. As shown in Figure 1, Figure 1 shows the minimum radius (R) of the microspheres. min ) and the original microsphere radius (R), where A in Figure 1 is an example of a spherical microsphere, and R min Equal to R. B, C, and D represent an example of non-spherical microspheres, namely R min Less than 0.75 times R. It should also be noted that the sphericity ratio and average sphericity in this article have different meanings and are calculated in different ways. Therefore, the values ​​of the sphericity ratio and average sphericity of the same microsphere are also different.

[0044] The asphericity ratio can be any value within 5%, for example, 0-5%, 0.1%-5%, 1%-4%, 2%-3%, etc.; for example, within 5%, within 4%, within 3%, within 2%, within 1%, within 0.5%, within 0.4%, within 0.3%, within 0.2%, within 0.1%, 0%, etc.

[0045] The average particle size of the radioactive microspheres can be any value within the range of 25 to 40 μm, for example, 30 to 35 μm. This range facilitates the distribution of the microspheres in the target organ, helping to improve therapeutic efficacy and reduce side effects. It is understood that the average particle size can be any value within the range of 25 to 40 μm, for example, 25 μm, 28 μm, 30 μm, 32.5 μm, 35 μm, 40 μm, etc.

[0046] In some embodiments, in the suspension, the number of radioactive microspheres ranging from 20 μm to 60 μm accounts for more than 85%. For example, more than 90%, and another example is more than 95%. Within this range, it is beneficial to the distribution of microspheres in the target organ, helping to improve the therapeutic effect and reduce side effects. It is understandable that the proportion of radioactive microspheres ranging from 20 μm to 60 μm can be any value greater than 85%, such as 85%, 88%, 90%, 95%, 98%, etc. It should be noted that the proportion of radioactive microspheres ranging from 20 μm to 60 μm refers to the ratio of the number of microspheres with a particle size within this range to the total number of microspheres, where the total number of microspheres includes both spherical microspheres and non-spherical microspheres. Therefore, microspheres within the range of 20 μm to 60 μm include both spherical microspheres and non-spherical microspheres, and microspheres outside this range also include spherical and non-spherical microspheres.

[0047] In some embodiments, in order to better load radioactive nuclides, the resin microspheres are selected from but not limited to sulfonated, nitrated or carbonized resin microspheres. When the resin microspheres are sulfonated or nitrated resin microspheres, there are sulfonic acid groups or nitric acid groups on their surface, and the radioactive nuclides are connected to the sulfonic acid groups or nitric acid groups and are mostly distributed on the surface of the microspheres. When the resin microspheres are carbonized resin microspheres, they are specifically carbon microspheres. The surface of the carbon microspheres contains mesopores, and the radioactive nuclides are distributed in the pores of the mesopores in the form of complexes. Since carbon microspheres are non-degradable, non-spherical carbon microspheres are more likely to induce inflammatory reactions. Therefore, compared with microspheres made of other materials, controlling the non-spherical particles of carbon microspheres to within 5% can reduce irritation and inflammatory reactions, as well as reduce the incidence of adverse reactions. The effect is more significant.

[0048] In some embodiments, the material of the resin microspheres is selected from, but not limited to, at least one of polystyrene, polyethylene, or polydivinylbenzene, or a cross-linked polymer thereof. In some embodiments, the material of the resin microspheres comprises phenolic resin microspheres. In some embodiments, the resin microspheres are cross-linked polystyrene microspheres having a cross-linking degree of 2% to 10%, such as 4%, 6%, or 8%. Within this range, both microsphere strength and loading rate requirements can be met. In some embodiments, the resin microspheres are selected from sulfonated or nitrated cross-linked polystyrene. In some embodiments, the material of the resin microspheres is selected from polystyrene partially cross-linked with divinylbenzene. In some embodiments, the resin microspheres are selected from sulfonated polystyrene partially cross-linked with divinylbenzene.

[0049] In some embodiments, the radionuclide is an isotope of at least one of yttrium, lutetium, indium, holmium, samarium, iodine, phosphorus, iridium, or rhenium. In some embodiments, the radionuclide is yttrium [ 90 Y].

[0050] In some embodiments, the radionuclide is yttrium [ 90 Y], the material of the resin microspheres is selected from sulfonated polystyrene partially cross-linked with divinylbenzene, and the suspension further contains water for injection. In some embodiments, the yttrium-containing [ 90Y] activity is 300 to 700 MBq, preferably 500 to 700 MBq. In some embodiments, each 1 mL of the suspension contains 2 to 3 mg of resin microspheres. In some embodiments, the suspension further contains a radioactive nuclide compound, such as yttrium chloride and / or yttrium sulfate. In some embodiments, the suspension further contains sulfate, wherein a small amount of sulfate is present in the aqueous solution. In some embodiments, the sulfate is sodium sulfate. In some embodiments, the suspension further contains a buffer, such as a phosphate buffer. The embodiments of the present application also provide a suspension containing radioactive carbon microspheres, the radioactive carbon microspheres comprising carbon microspheres and radionuclides loaded on the carbon microspheres, the average particle size of the radioactive carbon microspheres being 25 to 40 μm (micrometers), and the non-spherical ratio of the radioactive microspheres being within 5%.

[0051] Accordingly, an embodiment of the present application also provides a method for preparing a suspension of radioactive microspheres, comprising: mixing resin microspheres and a radioactive nuclide compound in a solution, and reacting to obtain the suspension containing the radioactive microspheres; the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the asphericity ratio is within 5%.

[0052] In some embodiments, the resin microspheres are further subjected to sulfonation, nitration or carbonization before being mixed with the radionuclide compound.

[0053] When the resin microspheres are sulfonated, in some embodiments, the method for preparing a suspension of radioactive microspheres comprises the following steps:

[0054] S10. placing the resin microspheres in concentrated sulfuric acid to undergo a sulfonation reaction, thereby obtaining sulfonated resin microspheres.

[0055] S20. Mixing the sulfonated microspheres and the radioactive nuclide compound in a solution to react to obtain the suspension containing the radioactive microspheres.

[0056] In some embodiments, in step S10, the sulfonation reaction is performed under an inert atmosphere or nitrogen, such as nitrogen or argon, to prevent the oxidation reaction during the preparation process from affecting the microsphere morphology, thereby facilitating the control of the non-spherical ratio of the radioactive microspheres.

[0057] In some embodiments, in step S10, the temperature of the sulfonation reaction is 35 to 80°C (degrees Celsius), for example: 35°C, 40°C, 50°C, 60°C, 70°C or 80°C. The time is 3 to 6 hours (hours), for example: 4h, 5h or 6h. Based on the above embodiment, in some embodiments, the concentrated sulfuric acid is added in batches during the sulfonation reaction. The specific scheme is: first, the resin microspheres are mixed with a small amount of concentrated sulfuric acid, and the temperature is slowly increased to a specific temperature at a heating rate of 1 to 3°C / min (degrees Celsius / minute) while stirring, and then the remaining concentrated sulfuric acid is added for sulfonation. In some embodiments, during the mixing process of the microspheres with a small amount of concentrated sulfuric acid, the mass ratio of the resin microspheres to the concentrated sulfuric acid is 1g: (1.5 to 2) mL. After the remaining concentrated sulfuric acid is added, the mass ratio of the resin microspheres to the concentrated sulfuric acid is 1g: (3 to 6) mL. In this way, the method of adding concentrated sulfuric acid in batches can not only achieve a better sulfonation effect, but also improve the problem of excessive heat affecting the microsphere morphology during the sulfonation reaction, thereby controlling the non-spherical ratio of the radioactive microspheres.

[0058] In some embodiments, in step S10, the sulfonation reaction is conducted under an inert atmosphere or nitrogen, and the concentrated sulfuric acid is added in multiple portions during the sulfonation reaction. For example, under initial conditions, 20%-70% of the required amount of concentrated sulfuric acid, such as 30%-68%, 33%-50%, or 50%-68%, is initially added. The remaining concentrated sulfuric acid is then added after the reaction temperature reaches a predetermined temperature. These conditions are advantageous for controlling the non-spherical ratio of the radioactive microspheres to within 5%.

[0059] In some embodiments, in step S20, the radionuclide compound is yttrium chloride, and the concentration of the yttrium chloride solution is 1 to 3 mg / mL, for example: 1 mg / mL, 1.5 mg / mL, 2 mg / mL, 2.5 mg / mL, 3 mg / mL, etc. In some embodiments, the yttrium chloride solution includes yttrium chloride [ 90 Y] and yttrium chloride mixture, determine the yttrium chloride [ 90 Y] amount.

[0060] In some embodiments, during the reaction of sulfonated, nitrated or carbonized resin microspheres with the radionuclide compound, the reaction temperature is 25 to 40°C, for example, 25°C, 30°C, 35°C, 40°C, and the reaction time is 1 to 2 hours, for example, 1 hour, 1.5 hours, 1.8 hours, 2 hours.

[0061] When the resin microspheres are carbonized, in some embodiments, the method for preparing a suspension of radioactive microspheres comprises the following steps:

[0062] S100. In an inert atmosphere or a nitrogen atmosphere, calcining the resin microspheres to obtain carbon microspheres.

[0063] S200. Mixing the carbon microspheres and the radioactive nuclide compound in a solution to react to obtain the suspension containing the radioactive microspheres.

[0064] In some embodiments, the microspheres are calcined at a temperature of 400 to 800° C. in step S100, for example, 400° C., 500° C., 600° C., 700° C., 800° C., etc., particularly 400 to 600° C.; and for a time of 3 to 6 hours, for example, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 6 hours, etc., particularly 3 to 4 hours. Based on the above embodiments, in some embodiments, the calcination temperature rise process adopts a step-by-step temperature rise, specifically: first, the temperature is rapidly raised from room temperature to 150° C. to 200° C. at a rate of 4 to 12° C. / min, then the temperature is slowly raised at a rate of 1 to 2° C. / min (degrees Celsius / minute) above 150° C. to a specific calcination temperature, and then calcined. In another specific embodiment, the temperature is first rapidly raised from room temperature to 150°C to 200°C, then slowly raised at a rate of 1.6-2°C / min above 150°C to 200°C to 300°C, and then slowly raised at a rate of 1-1.5°C / min to a specific calcination temperature. This stepwise heating method not only improves production efficiency but also allows for control of the non-spherical ratio of the radioactive microspheres.

[0065] In some embodiments, in step S100, the calcined carbon microspheres are further subjected to a washing step and a drying step. For example, the washing step may be performed using dilute nitric acid and deionized water. The drying step may be performed using vacuum drying or a forced air drying oven.

[0066] In some embodiments, to achieve better complexation, a precipitant is added before or after mixing the carbon microspheres and the radionuclide compound in the solution in step S200. For example, in some specific embodiments, the method for preparing the radioactive carbon microspheres includes any one of the following methods 1 or 2:

[0067] Method 1: After mixing carbon microspheres and a solution containing a radioactive nuclide compound, a solution containing a precipitant is added to obtain radioactive carbon microspheres through reaction.

[0068] Method 2: After mixing carbon microspheres and a solution containing a precipitant, a solution containing a radioactive nuclide compound is added to obtain radioactive carbon microspheres through reaction.

[0069] In this way, radioactive nuclides can be generated and grown in the mesopores of the carbon microspheres, thereby obtaining radioactive carbon microspheres with a higher degree of load firmness. On this basis, the inventors found that the generation rate of radioactive nuclides in the mesopores of the carbon microspheres is too fast or the generation amount is too much, which can cause the mesoporous structure to collapse, thereby increasing the non-spherical ratio of the carbon microspheres. Therefore, the generation rate and generation amount of radioactive nuclides in the mesopores are controlled by controlling the concentration of the precipitant and the radioactive nuclides. In view of this, in some embodiments, the concentration of the precipitant is 5mg / mL to 10mg / mL (milligrams per milliliter). For example, 5mg / mL, 6mg / mL, 8mg / mL, 10mg / mL, etc. In some embodiments, the concentration of the radioactive nuclides is 3mg / mL to 6mg / mL, for example, 3mg / mL, 5mg / mL, 6mg / mL, etc. Controlling the precipitant and the radioactive nuclides within this range can not only meet the radioactive nuclide loading amount, but also slow down the generation rate and generation amount of radioactive nuclides in the mesopores, which is conducive to controlling the non-spherical ratio of the carbon microspheres.

[0070] In some embodiments, in step S100, the microsphere carbonization process first involves rapidly heating the microspheres from room temperature to 150°C to 200°C at a rate of 4°C / min, then slowly heating the microspheres to 400°C to 600°C at a rate of 1°C / min to 2°C / min, and calcining the microspheres for 3 to 4 hours. In step S200, the concentration of the precipitant is 5 mg / mL to 10 mg / mL, and the concentration of the radionuclide is 3 mg / mL to 6 mg / mL. This helps to control the non-sphericity ratio of the carbon microspheres to within 5%.

[0071] In some embodiments, the radionuclide compound is selected from but not limited to yttrium sulfate [ 90 Y] or yttrium chloride [ 90 Y]. The precipitant is selected from but not limited to at least one of tartaric acid, EDTA and sodium phosphate, for example, one or two. For example:

[0072] When the precipitant is selected from one, such as EDTA, the radionuclide compound is selected from yttrium chloride [ 90 Y] When. For example, the preparation method of radioactive carbon microspheres includes: washing the carbon microspheres and 90 The YCl3 solution was mixed evenly and allowed to stand for 12 hours. EDTA was then added to the mixture and shaken on a shaker for 1 hour. The mixture was washed and dried to obtain 90 Y-EDTA complex-loaded carbon microspheres.

[0073] When the precipitant is selected from one, such as tartaric acid, the radionuclide compound is selected from yttrium chloride [ 90 Y] When. For example, the preparation method of carbon microspheres includes: washing the carbon microspheres and 90The YCl3 solution was mixed evenly and allowed to stand for 12 hours. Tartaric acid was then added to the mixture and shaken on a shaker for 1 hour. The mixture was washed and dried to obtain 90 Gamma-tartaric acid complex-loaded carbon microspheres.

[0074] When the precipitant is selected from two, such as tartaric acid and sodium phosphate, the radionuclide compound is selected from yttrium chloride [ 90 Y] When. For example, the preparation method of carbon microspheres includes: washing the carbon microspheres and 90 The YCl3 solution was mixed evenly and allowed to stand for 12 hours. Tartaric acid was then added to the mixture and shaken on a shaker for 1 hour. The mixture was washed and dried to obtain 90 The carbon microspheres loaded with Y-tartaric acid complex were then 90 The carbon microspheres loaded with the Y-tartaric acid complex were added to the sodium phosphate solution, shaken in a shaker for 1 h, washed and dried to obtain 90 Y-PO4 complex-loaded carbon microspheres.

[0075] In some embodiments, the solvents of the resin microspheres, the solution of the radionuclide compound, and the precipitant solution are all water for injection.

[0076] The present application also provides a method for preparing a suspension of radioactive carbon microspheres, comprising: mixing carbon microspheres and a radionuclide compound in a solution, and reacting to obtain the suspension containing the radioactive carbon microspheres; the radioactive carbon microspheres have an average particle size of 25 μm to 40 μm, and a non-spherical ratio of less than 5%.

[0077] Accordingly, the present application also provides the use of the above suspension in the preparation of drugs for treating tumors.

[0078] In some embodiments, the tumor is a vascularized solid tumor. In some embodiments, the tumor is a primary or secondary liver cancer.

[0079] Furthermore, the present application provides a method for treating tumors, comprising administering the suspension to a tumor patient. The suspension, due to its inclusion of radioactive microspheres with a lower non-spherical ratio, exhibits improved uniformity, resulting in a more optimal tumor distribution density during treatment, significantly improving efficacy, and exhibiting improved safety with a reduced incidence of adverse reactions.

[0080] In some embodiments, the treatment method comprises delivering the suspension to the tumor site. Specifically, the suspension can be administered into the arterial blood supply of the target organ to achieve radiotherapy of the tumor site of the target organ. For example, a liver tumor can be treated by inserting a catheter into the hepatic artery, and then delivering the suspension to the liver tumor through the catheter. The suspension can be administered as a single dose or multiple doses until the desired radiation level is achieved.

[0081] The following examples will be used to more clearly and specifically illustrate the technical solutions of the present disclosure. It should be understood that these examples are for illustrative purposes only and are in no way intended to limit the scope of protection of the present disclosure. The scope of protection of the present disclosure is defined solely by the claims.

[0082] Unless otherwise stated, the reagents and instruments used in the following examples are all conventional products that can be obtained commercially. Unless otherwise stated, experiments were conducted under conventional conditions or conditions recommended by the manufacturer. In the following examples, the polystyrene microspheres used for sulfonation treatment were selected from the commercially available cross-linked polystyrene-divinylbenzene polymer microspheres AmberChromTM XT30 with an average particle size of 30 μm and a cross-linking degree within the range of 2% to 10% and sold by Dupont. The polystyrene microspheres used for carbonization treatment were selected from the commercially available cross-linked polystyrene-divinylbenzene polymer microspheres with an average particle size of 50 μm and a cross-linking degree within the range of 2% to 10% and sold by Qingdao Hongpu Biotechnology Co., Ltd. (hereinafter referred to as "polystyrene microspheres"). Sulfonated polystyrene microspheres were selected from the cation exchange resin Aminex 50W-X4 (Biorad, Hercules, CA) with an average particle size of 30 μm. Yttrium chloride [ 90 Y] and yttrium sulfate [ 90 Y] was obtained by the decay of strontium-90. The activity of the radioactive agent was measured by a Capintec (CRC-55TW) activity meter from the United States.

[0083] 1. Preparation Example

[0084] Example 1

[0085] This embodiment provides a suspension containing radioactive polystyrene microspheres, and the preparation steps are as follows:

[0086] (1) After washing and drying the polystyrene microspheres with anhydrous ethanol, they were ultrasonically dispersed in a small amount of concentrated sulfuric acid (1 g: 2 mL) in an Ar atmosphere. The temperature was raised to 75 °C at a rate of 1 °C / min under stirring at 300 r / min, and the remaining concentrated sulfuric acid was added (to 1 g: 6 mL). The reaction was allowed to proceed for 6 h to obtain sulfonated polystyrene microspheres, which were then washed and dried.

[0087] (2) Add yttrium chloride solution (yttrium chloride [ 90 A mixture of yttrium chloride and yttrium chloride (2 mg / mL in total) was stirred and mixed evenly with 2 g of sulfonated polystyrene microspheres, and the reaction was carried out at 40°C for 2 h. After washing, the suspension was resuspended in 10 mL of water to obtain a suspension of radioactive polystyrene microspheres.

[0088] Example 2

[0089] This embodiment provides a suspension containing radioactive polystyrene microspheres, and the preparation steps are as follows:

[0090] (1) After washing and drying the polystyrene microspheres with anhydrous ethanol, they were ultrasonically dispersed in a small amount of concentrated sulfuric acid (1 g: 2 mL) in an Ar atmosphere. The temperature was raised to 75 °C at a rate of 2 °C / min under stirring at 300 r / min. The remaining concentrated sulfuric acid was added (to 1 g: 6 mL) and the reaction was continued for 6 h to obtain sulfonated polystyrene microspheres, which were then washed and dried.

[0091] (2) Add yttrium chloride solution (yttrium chloride [ 90 A mixture of yttrium chloride and yttrium chloride (2.25 mg / mL in total) was mixed with 2 g of sulfonated polystyrene microspheres by stirring, and the mixture was subjected to a loading reaction at 40°C for 2 h. After washing, the mixture was resuspended in 10 mL of water to obtain a suspension of radioactive polystyrene microspheres.

[0092] Example 3

[0093] This embodiment provides a suspension containing radioactive polystyrene microspheres, and the preparation steps are as follows:

[0094] (1) The polystyrene microspheres were washed and dried with anhydrous ethanol, and then ultrasonically dispersed in a small amount of concentrated sulfuric acid (1 g: 2 mL). The mixture was stirred at 300 r / min, and then heated to 75 °C at a rate of 2 °C / min. The remaining concentrated sulfuric acid was added (added to 1 g: 6 mL) and reacted for 6 h to obtain sulfonated polystyrene microspheres, which were then washed and dried.

[0095] (2) Add yttrium chloride solution (yttrium chloride [ 90 A mixture of yttrium chloride and yttrium chloride (2.25 mg / mL in total) was mixed with 2 g of sulfonated polystyrene microspheres by stirring, and the mixture was subjected to a loading reaction at 40°C for 2 h. After washing, the mixture was resuspended in 10 mL of water to obtain a suspension of radioactive polystyrene microspheres.

[0096] Example 4

[0097] This embodiment provides a suspension containing radioactive polystyrene microspheres, and the preparation steps are as follows:

[0098] (1) After washing and drying the polystyrene microspheres with anhydrous ethanol, they were ultrasonically dispersed in a small amount of concentrated sulfuric acid (1 g: 1.5 mL) in a nitrogen atmosphere. The mixture was stirred at 300 r / min and then heated to 80°C at a rate of 3°C / min. The remaining concentrated sulfuric acid was added (to 1 g: 3 mL) and reacted for 6 h to obtain sulfonated polystyrene microspheres, which were then washed and dried.

[0099] (2) Add yttrium chloride solution (yttrium chloride [ 90 A mixture of yttrium chloride and yttrium chloride (1 mg / mL in total) was mixed with 2 g of sulfonated polystyrene microspheres by stirring, and the mixture was loaded and reacted at 40°C for 2 h. After washing, the mixture was resuspended in 10 mL of water to obtain a suspension of radioactive polystyrene microspheres.

[0100] Example 5

[0101] This embodiment provides a suspension containing radioactive polystyrene microspheres, and the preparation steps are as follows:

[0102] (1) After washing and drying the polystyrene microspheres with anhydrous ethanol, they were ultrasonically dispersed in a small amount of concentrated sulfuric acid (1 g: 2 mL) in an Ar atmosphere. The mixture was stirred at 300 r / min and then heated to 80 °C at a rate of 1 °C / min. The remaining concentrated sulfuric acid was added (to 1 g: 3 mL) and reacted for 3 h to obtain sulfonated polystyrene microspheres, which were then washed and dried.

[0103] (2) Add yttrium chloride solution (yttrium chloride [ 90 A mixture of yttrium chloride and yttrium chloride (3 mg / mL in total) was mixed with 2 g of sulfonated polystyrene microspheres by stirring, and the mixture was subjected to a loading reaction at 40°C for 2 h. After washing, the mixture was resuspended in 10 mL of water to obtain a suspension of radioactive polystyrene microspheres.

[0104] Example 6

[0105] This embodiment provides a suspension containing radioactive carbon microspheres, and the preparation steps are as follows:

[0106] (1) Polystyrene microspheres were calcined at 400 °C for 4 h in an Ar atmosphere to obtain carbon microspheres (the temperature was raised from room temperature to 200 °C at a rate of 10 °C / min, then to 300 °C at a rate of 2 °C / min, then to 400 °C at a rate of 1 °C / min, maintained for 4 h, and then cooled at a rate of 10 °C / min). The carbon microspheres were then washed twice with 0.3 mol / L dilute nitric acid and deionized water, dried, and sieved.

[0107] (2) 2 g of carbon microspheres were mixed with tartaric acid solution (5 mg / mL) and allowed to stand for 12 h. Then 5 GBq of yttrium chloride solution (yttrium chloride [ 90 A mixture of Y] and yttrium chloride, 3 mg / mL) was shaken in a thermostatic shaker at 25°C for 1 h (total volume of the solution was 20 mL) to obtain a suspension of radioactive carbon microspheres.

[0108] Example 7

[0109] This embodiment provides a suspension containing radioactive carbon microspheres, and the preparation steps are as follows:

[0110] (1) Polystyrene microspheres were calcined at 400 °C for 4 h in an Ar atmosphere to prepare carbon microspheres (the temperature was raised from room temperature to 200 °C at a rate of 10 °C / min, then to 400 °C at a rate of 2 °C / min, maintained for 4 h, and then cooled at a rate of 10 °C / min). The carbon microspheres were then washed twice with 0.3 mol / L dilute nitric acid and deionized water, dried, and sieved.

[0111] (2) 2 g of carbon microspheres were mixed with tartaric acid solution (10 mg / mL) and allowed to stand for 12 h. Then 5 GBq of yttrium chloride solution (yttrium chloride [ 90 A mixture of Y] and yttrium chloride, 6 mg / mL) was shaken in a thermostatted shaker at 25°C for 1 h (total volume of the solution was 20 mL) to obtain a suspension of radioactive carbon microspheres.

[0112] Example 8

[0113] This embodiment provides a suspension containing radioactive carbon microspheres, which is prepared by the following steps:

[0114] (1) Polystyrene microspheres were calcined at 400 °C for 4 h in an Ar atmosphere to prepare carbon microspheres (the temperature was raised from room temperature to 200 °C at a rate of 10 °C / min, then to 400 °C at a rate of 2 °C / min, maintained for 4 h, and then cooled at a rate of 10 °C / min). The carbon microspheres were then washed twice with 0.3 mol / L dilute nitric acid and deionized water, dried, and sieved.

[0115] (2) 2 g of carbon microspheres were mixed with tartaric acid solution (25 mg / mL) and allowed to stand for 12 h. Then 5 GBq of yttrium chloride solution (yttrium chloride [ 90 A mixture of Y] and yttrium chloride, 12.5 mg / mL) was shaken in a thermostatted shaker at 25°C for 1 h (total volume of the solution was 20 mL) to obtain a suspension of radioactive carbon microspheres.

[0116] Example 9

[0117] This embodiment provides a suspension containing radioactive carbon microspheres, and the preparation steps are as follows:

[0118] (1) Polystyrene microspheres were calcined at 600 °C for 3 h in an Ar atmosphere to prepare carbon microspheres (the room temperature was heated to 150 °C at a rate of 10 °C / min, then to 600 °C at a rate of 2 °C / min, maintained for 3 h, and then cooled at a rate of 10 °C / min). The carbon microspheres were then washed twice with 0.3 mol / L dilute nitric acid and deionized water, dried, and sieved.

[0119] (2) 2 g of carbon microspheres were mixed with tartaric acid solution (10 mg / mL) and allowed to stand for 12 h. Then 5 GBq of yttrium chloride solution (yttrium chloride [ 90 A mixture of Y] and yttrium chloride, 5 mg / mL) was shaken in a thermostatic shaker at 25°C for 1 h (total volume of the solution was 20 mL) to obtain a suspension of radioactive carbon microspheres.

[0120] Example 10

[0121] This embodiment provides a suspension containing radioactive carbon microspheres, and the preparation steps are as follows:

[0122] (1) Polystyrene microspheres were calcined at 500 °C for 3 h in an Ar atmosphere to obtain carbon microspheres (the room temperature was heated to 200 °C at a rate of 10 °C / min, then to 500 °C at a rate of 2 °C / min, maintained for 3 h, and then cooled at a rate of 10 °C / min). The carbon microspheres were then washed twice with 0.3 mol / L dilute nitric acid and deionized water, dried, and sieved.

[0123] (2) 2 g of carbon microspheres were mixed with 5 GBq of yttrium chloride solution (yttrium chloride [ 90 A mixture of yttrium chloride (Y) and yttrium chloride (4 mg / mL) was mixed evenly and allowed to stand for 12 h. Then, tartaric acid solution (8 mg / mL) was added to the mixture and shaken in a constant temperature shaker at 25°C for 1 h (total solution volume was 20 mL) to obtain a suspension of radioactive carbon microspheres.

[0124] Comparative Example 1

[0125] This embodiment provides a suspension containing radioactive polystyrene microspheres, and the preparation steps are as follows:

[0126] (1) The polystyrene microspheres were washed and dried with anhydrous ethanol, and then ultrasonically dispersed in an appropriate amount of concentrated sulfuric acid (1 g: 6 mL). The mixture was stirred at 300 r / min and reacted at 75°C for 6 h to obtain sulfonated polystyrene microspheres, which were then washed and dried.

[0127] (2) Add yttrium chloride solution (yttrium chloride [ 90 A mixture of yttrium chloride (Y) and yttrium chloride (2.25 mg / mL) was mixed with 2 g of sulfonated polystyrene microspheres by stirring, and the mixture was loaded and reacted at 40°C for 2 h. After washing, the mixture was resuspended in 10 mL of water to obtain a suspension of radioactive polystyrene microspheres.

[0128] Comparative Example 2

[0129] A suspension containing radioactive polystyrene microspheres is provided, and the preparation steps are as follows:

[0130] (1) 2 g of commercially available sulfonated polystyrene microspheres were added to water and then mixed with 5 GBq of yttrium sulfate solution (yttrium chloride [ 90 Y] and yttrium chloride mixture, a total of 2.25 mg / mL) loading reaction for 2h.

[0131] (2) The microspheres were washed with phosphate buffer solution and then resuspended in 10 mL of water to obtain a suspension of radioactive polystyrene microspheres.

[0132] Comparative Example 3

[0133] A suspension containing radioactive carbon microspheres is provided, and the preparation steps are as follows:

[0134] (1) Polystyrene microspheres were calcined at 400 °C for 4 h in an Ar atmosphere to prepare carbon microspheres (the temperature was raised from room temperature to 200 °C at a rate of 10 °C / min, then to 400 °C at a rate of 3 °C / min, maintained for 4 h, and then cooled at a rate of 10 °C / min). The carbon microspheres were then washed twice with 0.3 mol / L dilute nitric acid and deionized water, dried, and sieved.

[0135] (2) 2 g of carbon microspheres were mixed with tartaric acid solution (25 mg / mL) and allowed to stand for 12 h. Then 5 GBq of yttrium chloride solution (yttrium chloride [ 90 A mixture of Y] and yttrium chloride, 12.5 mg / mL) was shaken in a thermostatted shaker at 25°C for 1 h (total volume of the solution was 20 mL) to obtain a suspension of radioactive carbon microspheres.

[0136] Comparative Example 4

[0137] A suspension of radioactive resin microspheres is provided, and the preparation steps are as follows:

[0138] (1) Weigh 10 g of polystyrene / divinylbenzene microspheres (30 μm) and 120 g of ethylene dichloride, add 4.4 g of chloroacetyl chloride and 2 g of anhydrous aluminum chloride, react at 30°C for 24 h, wash with ethanol and deionized water in sequence, and dry at 90°C to obtain polymer microspheres containing chloroacetyl chloride functional groups on the surface;

[0139] (2) Weigh 5 g of the chloroacetyl chloride functional group microspheres prepared in step (1), add 10% sodium hydroxide solution, reflux for 12 h, wash with water three times, and dry at 90° C. for later use;

[0140] (3) Weigh 5 g of the microspheres prepared in step (2), add 100 mL of deionized water, mix and stir at 60° C., deoxygenate with nitrogen for 1 h, add 10 mL of 0.1 M cerium ammonium nitrate solution (dissolved in 1 M HNO 3 ), add 10 mL of glycidyl methacrylate (GMA) after 30 min, and react for 6 h. After the reaction, wash the product repeatedly with deionized water to obtain polymer microspheres with surface grafted GMA, which are represented by Poly-g-GMA.

[0141] (4) 1.6 g of iminodiacetic acid (IDA) and 1 g of NaOH were added to 50 mL of water to generate the sodium salt of IDA. Then, 1 g of Poly-g-GMA microspheres and 2 M Na2CO3 solution were added to the solution to adjust the pH to 10-11. The mixture was stirred at 60 °C for 12 h. After the reaction, the particles were repeatedly washed with deionized water. The product was represented by Poly-g-GMA-IDA.

[0142] (5) Weigh 1M yttrium chloride [ 90 20 g of Y] solution was thoroughly mixed with Poly-g-GMA-IDA microspheres and stirred at 40-50°C for 40-80 minutes. After the reaction was completed, the microspheres were washed repeatedly with physiological saline water 5 times, and 2 g of the microspheres were resuspended in 10 mL of water for injection to prepare a suspension of yttrium-90 radioactive resin microspheres.

[0143] 2. Effect Test Examples

[0144] Test Example 1

[0145] Determination of the non-sphericity ratio, particle size and particle size distribution of radioactive microspheres.

[0146] (1) Non-spherical ratio: Observe the morphology of the radioactive microspheres under a microscope and calculate the non-spherical ratio. The specific determination method is as follows:

[0147] Determination method: An appropriate amount of the radioactive microspheres in the suspensions prepared in Examples 1-10 and Comparative Examples 1-4 were placed on a disposable blood cell counting plate. The sample was placed under a trinocular microscope with the lid placed on the sample with the grid facing downward (literally upward). Four appropriate square areas of equal size were randomly selected on the disposable blood cell counting plate and observed and photographed at a magnification of 20-40 times. The non-spherical microspheres and the total number of microspheres in the four selected areas (including spherical and non-spherical microspheres) were counted.

[0148] Calculation method: non-spherical ratio = non-spherical microspheres / total number of microspheres * 100% (the final result is the average value of four regions).

[0149] Judgment Criteria: Non-spherical microspheres are defined as irregular particles with a minimum radius less than 75% of the original microsphere radius, excluding concave particles. See Figure 2 for details. Figure 2 shows actual microscopic observation of an example containing non-spherical microspheres, where the framed area represents the non-spherical microspheres. The final measured results of the non-spherical ratio are shown in Table 1 below.

[0150] (2) Particle size and particle size distribution: The determination method is the same as that of the non-spherical ratio. Use a disposable counting plate and a trinocular microscope to observe and take pictures, calculate the particle size, and based on the results, count the number of particles in the range of 20 μm to 60 μm and the total number of particles in the four selected areas.

[0151] Calculation method: Percentage of particles in the range of 20 μm to 60 μm = Number of particles in the range of 20 μm to 60 μm / Total number of particles * 100% (the final result is the average of the four regions).

[0152] Judgment criteria: Both non-spherical microspheres and spherical particles are included in the statistics. The particle size of non-spherical microspheres is calculated based on the straight-line distance between the two farthest endpoints on the microsphere.

[0153] (3) Average particle size: The average particle size of the radioactive microspheres was measured using a Malvern laser particle size analyzer (Mastersizer 3000).

[0154] The above tests were all performed after the radioactive microspheres had completely decayed.

[0155] The average particle size of the radioactive polystyrene microspheres and carbon microspheres provided in each embodiment and comparative example is in the range of 25 to 40 μm, and the number of radioactive microspheres in the range of 20 μm to 60 μm accounts for more than 85%. 90 The activities of the three compounds were all within the range of 500-700 MBq, with no significant difference.

[0156] Table 1

[0157] As can be seen from Table 1, using the method provided by this application, the non-sphericity ratio of the radioactive polystyrene microspheres and radioactive carbon microspheres of Examples 1 to 10 can be controlled within 10%. Specifically, the non-sphericity ratio of Examples 1 to 2, 4 to 7, and 9 to 10 can be controlled within 5%.

[0158] Test Example 2

[0159] Determine and evaluate whether and to what extent radioactive microspheres retained in tumor microcirculation stimulate mammals.

[0160] Test samples: radioactive microspheres provided in Examples 1 to 3, Examples 6 to 8, and Comparative Examples 1 and 3.

[0161] Reference material: high-density polyethylene film (HDPE) (Hatano Research Institute, FDSC, batch number C-212).

[0162] Experimental animals: The experimental animals were New Zealand white rabbits, normal grade, male; weight: 2.5-3.5 kg.

[0163] Experimental methods:

[0164] (1) White rabbits were divided into 8 groups, each containing 3 rabbits. The 8 groups corresponded to Examples 1 to 3, Examples 6 to 8, and Comparative Examples 1 and 3, respectively. Within 24 hours before the experiment, the hair on both sides of the animals' backs was removed. The anesthetized animals were placed prone on the operating table. Isoflurane anesthesia was used during the operation and maintained to prevent muscle tremors.

[0165] (2) After the sample is left to decay, centrifuge to remove the liquid in the suspension.

[0166] (3) Make a longitudinal incision along the midline of the animal's back skin, separate the fascia and expose the paraspinal muscles. Use a scalpel to make a small incision in the muscle. Use hemostatic forceps to place a certain amount of treated test article or control article (about 0.5g for resin microspheres and about 0.3g for carbon microspheres) into the incision as shown in Figure 3. Four test articles (T1, T2, T3, and T4) are implanted into the paraspinal muscles on the left side of each animal, and four control articles (C1, C2, C3, and C4) are implanted into the same muscles on the contralateral side.

[0167] (4) The day of implantation was defined as Day 1. All implants were placed approximately 25–50 mm from the midline and parallel to the midline, with approximately 2.5 cm between implants. After implantation, the muscles and skin were sutured with medical sutures. Sterile procedures were ensured during the implantation process, and the implantation cycle was 13 weeks.

[0168] (5) After the implantation period, the animals were euthanized and a longitudinal incision was made down the center of the rabbit's back to expose the paraspinal muscles. The paraspinal muscles that were large enough to encase the implant and not affected by the surgery were removed. All implantation sites were collected and fixed for macroscopic observation and histopathological evaluation.

[0169] Evaluation criteria:

[0170] The experimental results are mainly evaluated based on the results of histopathological examination. The specific rating process is as follows:

[0171] (1) Evaluate and record the cellular and tissue responses of the local surrounding tissues of each implant.

[0172] (2) Calculate the cellular response (scores in Table 2) and tissue response scores (scores in Table 3) at each implantation site.

[0173] (3) Calculate the total score of each site = total score of cell response × 2 + total score of tissue response.

[0174] (4) Average score of each test article = total score of the test article for that animal / number of effectively implanted test articles. Add the average score of each test article and divide by the number of animals to obtain the total average score of the test article. Calculate the total average score of the control article in the same way.

[0175] (5) Final reaction score = total average score of the test sample - total average score of the control sample (negative numbers are recorded as 0).

[0176] Based on the final reaction score, grade the degree of test article implantation reaction according to Table 4.

[0177] Table 2 Histological evaluation system - cell type / response

[0178] phf-high power microscope (400×) field of view

[0179] Table 3 Histological evaluation system - tissue response

[0180] Table 4 Grading table of local reaction after implantation

[0181] The experimental results are as follows:

[0182] No animals were found to be dying or dead during the experiment. Planned autopsies revealed no macroscopic changes related to the test article.

[0183] The final reaction scores of the test products compared with the control products are shown in Table 5 below.

[0184] Table 5. Implantation experiment results

[0185] As shown in Table 5, at 13 weeks of implantation, Examples 1, 2, 6, and 7 had relatively low scores, all within 2.9. Examples 3 and 8 had slightly higher scores, while Comparative Examples 1 and 3 had the highest scores, approaching 9.0. It can be seen that when the proportion of non-spherical radioactive microspheres in the suspension is less than 5%, the score is considered non-irritating. A non-spherical ratio greater than 5% indicates significant or even moderate irritation. This suggests that controlling the non-spherical ratio of radioactive microspheres in the suspension to less than 5% can significantly reduce local inflammatory reactions and improve safety.

[0186] Test Example 3

[0187] Determine and evaluate the distribution of microspheres in rabbit liver tumors.

[0188] Test samples: radioactive microspheres provided in Examples 1 to 3, Examples 6 to 8, and Comparative Examples 1 and 3.

[0189] Experimental animals: The experimental animals were New Zealand white rabbits, normal grade, male; weight: 2.5-3.5 kg.

[0190] Experimental methods:

[0191] (1) Establishing a tumor model

[0192] A VX2 rabbit liver transplant model was established using New Zealand white rabbits. A 2mm diameter VX2 tumor mass was implanted at the lower edge of the rabbit's liver. CT scans were performed 7 days later to record the location and size of the tumor mass. Success was considered successful when the tumor reached a maximum diameter of 1-2cm.

[0193] (2) Grouped administration

[0194] Animals were anesthetized preoperatively (2.5% sodium pentobarbital, 30 mg / kg). The groin was shaved, the skin was incised, and the femoral artery was bluntly dissected. The femoral artery was punctured under direct vision, and a 5F sheath was inserted. The femoral artery and sheath were secured with absorbable medical sutures. Under digital subtraction angiography (DSA) guidance, a 2.7F microcatheter was inserted into the common hepatic artery, and radioactive microspheres were injected through the microcatheter, minimizing microsphere reflux. After embolization, the catheter and sheath were removed, the femoral artery was ligated above the puncture site, and the muscle and skin were sutured layer by layer.

[0195] Rabbits were randomly divided into eight groups of three, corresponding to Examples 1-3, Examples 6-8, and Comparative Examples 1 and 3, respectively. After 1 GBq of the test sample was allowed to decay, it was perfused into the liver. After 24 hours, the animals were sacrificed and dissected. The livers were fixed with formalin, embedded in paraffin, and sectioned. stained with hematoxylin and eosin for pathological examination, and the distribution and density of the microspheres were calculated using the following method.

[0196] The observed area is divided into 4 parts:

[0197] 0-1 mm outside the tumor boundary, 0-1 mm inside the tumor boundary, non-tumor tissue, and deep in the tumor (greater than 1 mm inside the tumor boundary).

[0198] Within the field of view of the microscope (3 mm × 3 mm), calculate the distribution density of radioactive microspheres in each area (unit: particles / mm 2 The average distribution density of the corresponding area of ​​each test sample is calculated as follows:

[0199] Average distribution density = total distribution density in the corresponding area / number of animals.

[0200] The experimental results are shown in Table 6 below.

[0201] Table 6

[0202] As can be seen from Table 6, compared to Comparative Examples 1 and 3, Examples 1, 2, 6, and 7 generally have higher average distribution densities within the tumor, particularly within the deep portion of the tumor. Furthermore, the density outside the tumor and in non-tumor tissues has decreased. For example, the distribution density in non-tumor tissue in Example 1 is 0.1, while that in Comparative Example 1 is 1.4. The distribution density deep within the tumor in Example 1 is 1.8, while that in Comparative Example 1 is 0.5. This indicates that controlling the non-spherical ratio of the radioactive microspheres in the suspension to less than 5% can increase the distribution density within the tumor while reducing the density outside the tumor boundary.

[0203] Test Example 4

[0204] To determine and evaluate the therapeutic effect of radioactive microspheres on rabbit liver tumors.

[0205] Test substances: radioactive microspheres provided in Examples 2 and 7, and Comparative Examples 1 and 3.

[0206] Experimental animals: The experimental animals were New Zealand white rabbits, normal grade, male; weight: 2.5-3.5 kg.

[0207] Experimental methods:

[0208] (1) Establishing a tumor model

[0209] A VX2 rabbit liver transplant model was established using New Zealand white rabbits. A 2mm diameter VX2 tumor mass was inoculated into the lower central margin of the rabbit liver. A CT scan was performed seven days later to record the location and size of the tumor mass. Success was considered established when the tumor reached a maximum diameter of 1-2cm.

[0210] (2) Grouped administration

[0211] The rabbits were randomly divided into 5 groups, with 3 rabbits in each group. The 5 groups corresponded to Examples 2 and 7, Comparative Examples 1 and 3, and the model group, respectively. Examples 2 and 7, and Comparative Examples 1 and 3 were classified as the treatment group.

[0212] Model Group: Animals were anesthetized preoperatively (2.5% sodium pentobarbital, 30 mg / kg). The groin was shaved, the skin was incised, and the femoral artery was bluntly dissected. The femoral artery was punctured under direct vision, and a 5F sheath was inserted. The artery and sheath were secured with absorbable medical sutures. Under digital subtraction angiography (DSA) guidance, a 2.7F microcatheter was inserted into the common hepatic artery. Normal saline was injected through the microcatheter to minimize microsphere reflux. After embolization, the catheter and sheath were removed, the femoral artery was ligated above the puncture site, and the muscle and skin were sutured layer by layer.

[0213] A catheter was inserted into the rabbit's common hepatic artery, and normal saline was slowly injected through the catheter.

[0214] Treatment group: Each rat was given radioembolic microspheres with a dose of 1 GBq by surgical intervention, and the intervention method was the same as that of the model group.

[0215] Two weeks after administration, CT scans were performed to record the location and size of the tumors. The animals were then sacrificed, the tumors removed, and weighed. The tumor growth inhibition rate was calculated, and the results are shown in Table 7.

[0216] The tumor growth inhibition rate was calculated according to the following formula:

[0217] Tumor growth inhibition rate = (average tumor weight of animals in the model group - average tumor weight of animals in the treatment group) / average tumor weight of animals in the model group * 100%.

[0218] Table 7

[0219] As shown in Table 7, compared to Comparative Examples 1 and 3, Examples 2 and 7 exhibited higher tumor growth inhibition rates against liver tumors overall. For example, the tumor growth inhibition rate of Example 2 was 85.0%, while that of Comparative Example 1 was only 61.6%, both achieving an increase of more than 20% in tumor growth inhibition rate. This indicates that controlling the non-spherical ratio within 5% has a better tumor inhibition effect. This is because controlling the non-spherical ratio within 5% increases the distribution density of the microspheres within the tumor, thereby enhancing the tumor-killing ability.

[0220] Although the present invention has been described in detail above using general explanations, specific embodiments, and experiments, it will be apparent to those skilled in the art that modifications and improvements may be made based on the present invention. Therefore, such modifications and improvements, which do not depart from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A suspension, wherein: The invention comprises radioactive microspheres, wherein the radioactive microspheres include resin microspheres and radionuclides loaded on the resin microspheres, the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the non-spherical ratio of the radioactive microspheres is within 5%.

2. The suspension according to claim 1, wherein The non-spherical ratio refers to the ratio of the number of non-spherical radioactive microspheres to the total radioactive microspheres in the suspension, and the non-spherical radioactive microspheres refer to radioactive microspheres whose minimum radius is less than 75% of the radius of the original microspheres; and / or, in the suspension, the non-spherical ratio of the radioactive microspheres is within 2%; and / or, based on the number of the radioactive microspheres, the number of radioactive microspheres with a particle size of 20 μm to 60 μm in the suspension accounts for more than 85%; And / or, the material of the resin microspheres is selected from at least one of cross-linked polystyrene resin, cross-linked polyethylene resin and cross-linked polydivinylbenzene resin, preferably, the material of the resin microspheres is selected from polystyrene resin cross-linked with divinylbenzene having sulfonic acid groups; And / or, the resin microspheres are any one of resin microspheres with sulfonic acid groups, resin microspheres with nitro groups, and carbonized resin microspheres; And / or, the radionuclide is selected from at least one isotope of yttrium, lutetium, indium, holmium, samarium, iodine, phosphorus, iridium or rhenium, preferably, the radionuclide is selected from yttrium [ 90 Y]; And / or, the suspension further contains water for injection.

3. The suspension according to claim 1 or 2, wherein Each 1 mL of the suspension contains yttrium [90 Y] activity is 300~700MBq.

4. A suspension containing radioactive microspheres, wherein: The radioactive microspheres include resin microspheres and radionuclides loaded on the resin microspheres. The material of the resin microspheres includes at least one of polystyrene, polyethylene or polydivinylbenzene, or a cross-linked polymer thereof. The average particle size of the radioactive microspheres is 25 μm to 40 μm, and the non-spherical ratio is within 5%.

5. The suspension according to claim 4, wherein The non-spherical ratio refers to the ratio of the number of non-spherical radioactive microspheres to the total radioactive microspheres in the suspension, and the non-spherical radioactive microspheres refer to radioactive microspheres whose minimum radius is less than 75% of the radius of the original microspheres.

6. The suspension according to claim 4 or 5, wherein Calculated by the number of the radioactive microspheres, in the suspension, the number of radioactive microspheres with a particle size of 20 μm to 60 μm accounts for more than 85%, and / or the non-spherical ratio of the radioactive microspheres is within 2%; and / or the material of the resin microspheres is selected from cross-linked polystyrene microspheres with a cross-linking degree of 2% to 10%.

7. The suspension containing radioactive microspheres according to at least one of claims 4 to 6, characterized in that The resin microspheres are sulfonated, nitrated or carbonized resin microspheres.

8. The suspension containing radioactive microspheres according to at least one of claims 4 to 7, characterized in that The radioactive nuclide is selected from at least one isotope of yttrium, lutetium, indium, holmium, samarium, iodine, phosphorus, iridium or rhenium.

9. The suspension containing radioactive microspheres according to at least one of claims 4 to 8, wherein the material of the resin microspheres is selected from polystyrene resins cross-linked with divinylbenzene and having sulfonic acid groups.

10. The suspension containing radioactive microspheres according to at least one of claims 4 to 9, characterized in that The suspension also contains water for injection.

11. The suspension containing radioactive microspheres according to at least one of claims 4 to 10, wherein: The radionuclide is selected from yttrium [ 90 Y], each 1mL of the suspension contains yttrium [90 Y] activity is 300~700MBq.

12. The suspension containing radioactive microspheres according to at least one of claims 4 to 11, characterized in that The radionuclide is selected from yttrium [ 90 Y], the material of the resin microspheres is selected from sulfonated polystyrene partially cross-linked with divinylbenzene, and the suspension also contains water for injection, each 1 mL of yttrium [ 90 Y] activity is 300~700MBq.

13. A method for preparing a suspension containing radioactive microspheres, characterized in that: The method comprises: mixing resin microspheres and radioactive nuclide compounds in a solution, and reacting to obtain the suspension containing the radioactive microspheres; the material of the resin microspheres comprises at least one of polystyrene, polyethylene or polydivinylbenzene, or a cross-linked polymer thereof; the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the non-spherical ratio is within 5%.

14. The preparation method according to claim 13, characterized in that: Prior to being mixed with the radionuclide compound, the resin microspheres are subjected to sulfonation, nitration or carbonization.

15. A method for preparing a suspension, comprising: Mixing resin microspheres and radioactive nuclide compounds in a solution to react and obtain the suspension containing radioactive microspheres; In the suspension, the average particle size of the radioactive microspheres is 25 μm to 40 μm, and the non-spherical ratio is within 5%.

16. The preparation method according to claim 15, wherein: Prior to being mixed with the radionuclide compound, the resin microspheres are subjected to sulfonation, nitration or carbonization.

17. Use of the suspension according to any one of claims 1 to 12 or the suspension prepared by the method according to any one of claims 13 to 16 in preparing a drug for treating tumors, wherein: The tumor is preferably primary or secondary liver cancer.

18. A method for treating a tumor, comprising: A suspension is administered to a tumor patient, wherein the suspension comprises radioactive microspheres, wherein the radioactive microspheres comprise resin microspheres and radionuclides loaded on the resin microspheres, wherein the average particle size of the radioactive microspheres is 25 μm to The diameter of the radioactive microspheres is 40 μm, and the non-sphericity ratio of the radioactive microspheres is within 5%.

19. The method according to claim 18, wherein: The tumor is primary or secondary liver cancer.

20. The method according to claim 18 or 19, wherein: The non-spherical ratio refers to the ratio of the number of non-spherical radioactive microspheres to the total radioactive microspheres in the suspension, and the non-spherical radioactive microspheres refer to radioactive microspheres whose minimum radius is less than 75% of the radius of the original microspheres; And / or, the material of the resin microspheres is selected from at least one of cross-linked polystyrene resin, cross-linked polyethylene resin and cross-linked polydivinylbenzene resin, preferably, the material of the resin microspheres is selected from polystyrene resin cross-linked with divinylbenzene having sulfonic acid groups; And / or, the resin microspheres are any one of resin microspheres with sulfonic acid groups, resin microspheres with nitro groups, and carbonized resin microspheres; And / or, the radionuclide is selected from at least one isotope of yttrium, lutetium, indium, holmium, samarium, iodine, phosphorus, iridium or rhenium, preferably, the radionuclide is selected from yttrium [ 90 Y], 1 mL of the suspension contains yttrium [ 90 The Y] activity is preferably 300 to 700 MBq.

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