Phosphinoformic acid sustained release preparation as well as preparation method and application thereof

Abstract

The invention provides a phosphinic acid sustained release preparation as well as a preparation method and application thereof, and relates to the technical field of medicines, active ingredients comprise phosphinic acid calcium or phosphinic acid calcium and small-particle phosphinic acid monovalent metal salt; the particle size of the small-particle phosphinic acid monovalent metal salt is smaller than or equal to 14 micrometers, calcium phosphinate is insoluble salt, the solid of calcium phosphinate can be stored in eyes for a long time, the residence time of phosphinic acid in a vitreous cavity is prolonged, and the problem that in the prior art, the residence time of medicine molecules in the vitreous cavity is short can be solved. By combining the calcium phosphinate with the small-particle phosphinate monovalent metal salt, the dosage of calcium salt can be reduced, meanwhile, the release of phosphinate is kept in a short time, the slow release effect is improved, the drug effect exerting time is prolonged, and the problem that the drug effect is difficult to exert is solved.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical technology, and in particular to a phosphonoformic acid sustained-release formulation, its preparation method, and its application. Background Technology

[0002] Acute retinal necrosis syndrome (ARNS) is a rare and highly risky type of uveitis characterized by acute panuveitis, rapid progression of diffuse necrotizing retinitis, and occlusive inflammation of the retinal arteries. During its development, the necrotic area of ​​the retina spreads rapidly from the periphery to the posterior pole, and retinal detachment is a common late-stage complication. The most common viruses causing acute retinal necrosis include varicella-zoster virus, herpes simplex virus (types 1 and 2), cytomegalovirus, and Epstein-Barr virus (EBV).

[0003] The focus of treatment for acute retinal necrosis syndrome is controlling viral infection, reducing inflammation and retinal necrosis, and preventing onset in the contralateral eye. It generally requires a combination of drug therapy and surgery. Drug therapy mainly includes antiviral therapy, glucocorticoid anti-inflammatory therapy, and antiplatelet therapy. Surgery includes laser therapy and vitrectomy. Currently, there are no marketed or investigational drugs for this indication. The main antiviral drugs used clinically include acyclovir and ganciclovir. Although these drugs can inhibit viral replication and alleviate symptoms, they have low bioavailability and produce various adverse reactions (e.g., the most common adverse reaction is bone marrow suppression; approximately 40% of HIV patients who undergo long-term maintenance therapy experience a decrease in neutrophil count to 1000 / mm³). 3 Below this, approximately 20% of patients have a platelet count reduced to 1000 / mm³. 3The following are some symptoms of central nervous system disorders, such as mental abnormalities, tension, and tremors, with an incidence of approximately 5%; meanwhile, acute retinal necrosis syndrome progresses rapidly and carries a high risk of retinal detachment. The main drugs for glucocorticoid anti-inflammatory treatment include dexamethasone, hydrocortisone, prednisone, and betamethasone, which have anti-inflammatory, antiviral, anti-allergic, anti-shock, and immunosuppressive effects. However, as hormonal drugs, they can cause side effects affecting multiple systems throughout the body, such as metabolic disorders, osteoporosis and fractures, immunosuppression, skin and mucous membrane damage, gastrointestinal reactions, neuropsychiatric symptoms, and ocular complications. The incidence of side effects from glucocorticoid anti-inflammatory treatment is related to dosage and duration of treatment; long-term use increases the incidence of side effects. However, while laser surgery can prevent retinal detachment and reduce neovascularization, it can also lead to visual field impairment, and its effectiveness is uncertain when retinal necrosis is extensive or complicated by other factors. Vitrectomy can remove inflammatory substances from the eye, reduce inflammation, and decrease traction on the retina by removing affected vitreous tissue, thus lowering the risk of retinal detachment. However, as a surgical procedure, it carries the risk of adverse reactions such as infection, bleeding, and changes in intraocular pressure, and requires long-term eye care for postoperative recovery. Therefore, there is an urgent need to develop new treatments or methods to quickly control the condition and reduce complications and surgical risks.

[0004] Cytomegalovirus retinitis (CMVR) is an ocular disease caused by cytomegalovirus (CMV), commonly seen in immunocompromised individuals such as newborns, patients with acquired immunodeficiency syndrome (AIDS), and those undergoing immunosuppressive therapy or chemotherapy. This disease is characterized by full-thickness necrosis of the retina, accompanied by pathological changes such as hemorrhage and exudation. Especially when the lesions spread to the macula, it can severely impair vision, significantly impacting the patient's quality of life. Currently, there are no marketed or investigational drugs for this indication. However, the primary clinical treatment is antiviral therapy, with main drugs including ganciclovir (GCV), valganciclovir (VGCV), cidofovirhydrate (CDV), and foscarnet (FOS). Ganciclovir is a first-line treatment for cytomegalovirus (CMV) and offers multiple routes of administration, including oral, intravenous, intravitreal, and intraocular implants. However, long-term use can lead to drug resistance. Foscarnet has a different mechanism of action than ganciclovir. Ganciclovir is a nucleoside analog antiviral drug that blocks viral replication by inhibiting viral DNA polymerase and competitively terminating viral DNA chain synthesis. Foscarnet, on the other hand, is a non-nucleoside antiviral drug that primarily blocks viral DNA synthesis by directly inhibiting viral DNA polymerase. Foscarnet acts on the pyrophosphate binding site of viral DNA polymerase, inhibiting it in a non-competitive manner, thus preventing viral DNA replication. Therefore, foscarnet can be considered an alternative treatment option for intravenous and intravitreal administration.

[0005] However, due to the presence of the blood-eye barrier, the bioavailability of drugs administered intravenously is often very low; typically, less than 5% of the active ingredient crosses the retina and reaches the lesion. Furthermore, this route of administration can cause serious systemic side effects, such as allergic reactions, phlebitis, drug extravasation, and infection. In contrast, intravitreal administration is currently the most common and considered one of the most effective methods for treating retinal diseases. However, direct intravitreal injection also presents some problems. On the one hand, drug molecules typically have a short half-life within the vitreous cavity, thus requiring frequent and repeated injections to maintain intraocular drug concentration. On the other hand, patient discomfort during surgery makes long-term intraocular injection treatment difficult to tolerate, and frequent injections can damage the cornea and vitreous cavity, increasing the risk of ocular complications.

[0006] Therefore, in order to reduce the risks associated with direct intravitreal injection of drugs, it is an urgent clinical need to develop a sustained-release technology and / or drug suitable for intravitreal injection to prolong the drug's residence time and duration of action in the eye, thereby reducing the frequency of injections and the occurrence of complications.

[0007] In view of this, the present invention is hereby proposed. Summary of the Invention

[0008] One of the objectives of this invention is to provide a phosphonoformic acid sustained-release formulation to solve the technical problems of short residence time of drug molecules in the vitreous cavity and difficulty in exerting drug efficacy in the prior art.

[0009] The second objective of this invention is to provide a method for preparing the above-mentioned phosphonoformic acid sustained-release formulation.

[0010] A third objective of this invention is to provide the application of the above-mentioned phosphonocarboxylic acid sustained-release formulation or the phosphonocarboxylic acid sustained-release formulation prepared by the above-mentioned preparation method in the preparation of drugs for the prevention / treatment of viral retinal diseases.

[0011] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: In a first aspect, the present invention provides a phosphonoformic acid sustained-release formulation, the active ingredient of which includes calcium phosphonoformate, or calcium phosphonoformate and small-particle monovalent metal salts of phosphonoformate; wherein the particle size of the small-particle monovalent metal salts of phosphonoformate is ≤14μm.

[0012] Furthermore, it also includes triethyl acetyl citrate, wherein the active ingredient is suspended in triethyl acetyl citrate.

[0013] Furthermore, the mass ratio of the calcium phosphonate to the small-particle phosphonate monovalent metal salt is 2~15:2~12.

[0014] Furthermore, the mass ratio of the calcium phosphonoformate to the small-particle phosphonoformate monovalent metal salt is 3~12:2.5~10.

[0015] Furthermore, the mass ratio of the calcium phosphonate to the small-particle phosphonate monovalent metal salt is 3:2.5~10.

[0016] Furthermore, the small-particle phosphonocarboxylic acid monovalent metal salt is small-particle sodium phosphonocarboxylate or small-particle potassium phosphonocarboxylate.

[0017] Secondly, the present invention provides a method for preparing the above-mentioned phosphonoformic acid sustained-release formulation, comprising using calcium phosphonoformate as the active ingredient; or using calcium phosphonoformate and small-particle phosphonoformic acid monovalent metal salt as the active ingredients.

[0018] Furthermore, it also includes preparation by suspending the active ingredient in triethyl acetyl citrate.

[0019] Furthermore, the method for preparing the small-particle phosphonocarboxylic acid monovalent metal salt includes adding an aqueous solution of the phosphonocarboxylic acid monovalent metal salt dropwise into an antisolvent to precipitate the small-particle phosphonocarboxylic acid monovalent metal salt; Preferably, in the preparation of small-particle phosphonocarboxylic acid monovalent metal salt, the solubility of the phosphonocarboxylic acid monovalent metal salt aqueous solution is ≤10mg / mL, preferably 5mg / mL; Preferably, the preparation of small-particle phosphonocarboxylic acid monovalent metal salt further includes filtration and drying after precipitation to obtain small-particle phosphonocarboxylic acid monovalent metal salt solid; Preferably, the antisolvent comprises anhydrous ethanol.

[0020] Thirdly, the present invention provides the application of the above-mentioned phosphonocarboxylic acid sustained-release formulation or the phosphonocarboxylic acid sustained-release formulation prepared by the above-mentioned preparation method in the preparation of drugs for the prevention / treatment of viral retinal diseases. Preferably, the drug comprises a sustained-release drug; Preferably, the method of administration of the drug includes topical ocular administration; Preferably, the local ocular drug delivery includes at least one of intravitreal injection, intravitreal sustained-release implantation, continuous anterior chamber perfusion, or intracapsular implantation. Preferably, the dosage form of the drug includes at least one of the following: injection, microcapsule, intravitreal implant tablet / rod, sustained-release thrombus, microneedle patch, in-situ gel, or nanosphere.

[0021] The phosphonocarboxylic acid sustained-release formulation provided by this invention uses calcium phosphonocarboxylate, a sparingly soluble salt, whose solid form can remain in the eye for a long time, thus prolonging the residence time of phosphonocarboxylic acid in the vitreous cavity. This solves the problem of short residence time of drug molecules in the vitreous cavity in the prior art. Combining calcium phosphonocarboxylate with small-particle monovalent metal salts of phosphonocarboxylic acid can reduce the amount of calcium salt used, while maintaining the release of phosphonocarboxylic acid in a short time, improving the sustained-release effect, prolonging the duration of drug efficacy, and solving the problem of difficulty in achieving drug efficacy. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 A comparison chart of in vitro dispersion for 30 min of calcium phosphonate / ATEC suspension and sodium phosphonate / ATEC suspension of different concentrations provided in Experiment 1 of this invention; Figure 2This is a comparison chart of the in vitro dispersion of calcium phosphonate / ATEC suspension and sodium phosphonate / ATEC suspension at different concentrations provided in Experiment 1 of the present invention for 48 hours. Figure 3 A statistical chart showing the concentration and release of phosphonoformic acid in PBS for the 2.5 mg sodium phosphonoformate / ATEC suspension and the 5 mg sodium phosphonoformate / ATEC suspension provided in Experiment 1 of this invention; Figure 4 A statistical graph showing the concentration and release of phosphonoformic acid in PBS from the 10 mg sodium phosphonoformate / ATEC suspension provided in Experiment 1 of this invention; Figure 5 A statistical chart showing the concentration and release of phosphonoformic acid in PBS for the 3mg calcium phosphonoformate / ATEC suspension, 6mg calcium phosphonoformate / ATEC suspension, and 12mg calcium phosphonoformate / ATEC suspension provided in Experiment 1 of this invention; Figure 6 This is an observation of the rabbit's eye immediately after injection of the 10% calcium phosphonate / ATEC suspension provided in Experiment 2 of this invention. Figure 7 This is an observation of the intraocular condition of a rabbit on day 18 after injection of the 10% calcium phosphonate / ATEC suspension provided in Experiment 2 of this invention. Figure 8 This is an observation of the intraocular condition of a rabbit on the 30th day after injection of the 10% calcium phosphonate / ATEC suspension provided in Experiment 2 of this invention. Figure 9 This is an observation image of the pathological sections of the eyes of rabbit No. 9 provided in Experiment 3 of this invention; Figure 10 The image shows the appearance and ocular surface of the rabbit's eye on the 10th day after injection of the 40mg calcium phosphonate / ATEC suspension provided in Experiment 4 of this invention. Figure 11 The image shows the appearance and ocular surface of the rabbit's eye on day 100 after injection of the 40mg calcium phosphonate / ATEC suspension provided in Experiment 4 of this invention. Figure 12 The image shows the appearance and ocular surface of the rabbit's eye on day 226 after injection of the 40mg calcium phosphonate / ATEC suspension provided in Experiment 4 of this invention. Figure 13 The image shows a pathological section of the rabbit eye after injection of 40 mg calcium phosphonate / ATEC suspension provided in Experiment 4 of this invention. Detailed Implementation

[0024] Unless otherwise defined herein, the scientific and technical terms used in conjunction with this invention shall have the meanings commonly understood by one of ordinary skill in the art. The meaning and scope of terms shall be clear; however, in any case of potential ambiguity, the definitions provided herein shall prevail over any dictionary or foreign definitions. In this application, unless otherwise stated, the use of "or" means "and / or". Furthermore, the use of the term "comprising" and other forms is non-limiting.

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In this document, the terms “comprising” or “including” are open-ended expressions used in this disclosure to mean the phrase “including but not limited to”, and are used interchangeably with it, meaning that they include the contents specified in this disclosure, but do not exclude other contents.

[0027] In this document, the terms “optionally,” “optionally,” or “optionally” generally refer to an event or condition that may or may not occur as described below, and the description includes both cases in which the event or condition occurs and cases in which the event or condition does not occur.

[0028] In this document, “and / or” is used to indicate that one or both of the situations described may occur, for example, A and / or B includes (A and B) and (A or B).

[0029] In this document, unless otherwise stated, any numbering is used to distinguish one entity or behavior from another, and is not intended to require or imply any actual relationship, order or importance between these entities or behaviors, such as numbering i, ii; first, second, etc.

[0030] In this document, the terms “comprising” or “including” mean that the stated elements, integers or steps are included, but do not exclude any such elements, integers or steps.

[0031] In one aspect, the present invention provides a phosphonoformic acid sustained-release formulation, the active ingredient of which includes calcium phosphonoformate, or calcium phosphonoformate and small-particle monovalent metal salt of phosphonoformate; wherein the particle size of the small-particle monovalent metal salt of phosphonoformate is ≤14μm.

[0032] Calcium phosphonoformate is a sparingly soluble salt, and its solid form can remain in the eye for a long time, prolonging the residence time of phosphonoformate in the vitreous cavity. This solves the problem of short residence time of drug molecules in the vitreous cavity in existing technologies. Combining calcium phosphonoformate with small-particle monovalent metal salts of phosphonoformate can reduce the amount of calcium salt used, while maintaining the release of phosphonoformate in a short time, improving the sustained-release effect, prolonging the duration of drug efficacy, and solving the problem of difficulty in drug efficacy.

[0033] In practice, the ratio of calcium phosphonate and small-particle phosphonate monovalent metal salts can be adjusted according to the required amount of phosphonate.

[0034] The particle size of the small phosphonocarboxylic acid monovalent metal salt can be, but is not limited to, 0.1 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm or 14 μm, or any value ≤14 μm.

[0035] In some specific embodiments, the particle size of calcium phosphonate is at most 10 mm. 1 The order of magnitude is on the order of μm, preferably ≤14μm, and more preferably ≤10μm.

[0036] Carboxymethyl cellulose (CMV) solution was used as a solvent to deliver calcium phosphonate to prepare injectable sustained-release phosphonate formulations, which can be injected into the vitreous cavity. However, it was found that CMV could not keep calcium phosphonate in an encapsulated state for a long time without dispersion. As a result, when CMV was used as a carrier to deliver calcium phosphonate, it could not be uniformly and gradually released and dispersed to the delivery site after reaching the vitreous cavity.

[0037] In some specific embodiments, triethyl acetyl citrate (ATEC) is also included, in which the active ingredient is suspended. Using ATEC as a solvent to deliver the phosphonocarboxylic acid sustained-release formulation can promote uniform dispersion of phosphonocarboxylic acid at the delivery site (intravitreal cavity).

[0038] In some specific embodiments, the mass ratio of calcium phosphonoformate to small-particle phosphonoformate monovalent metal salt is 2~15:2~12. Specifically, the mass ratio of calcium phosphonoformate to small-particle phosphonoformate monovalent metal salt can be, but is not limited to, 1:1, 1:2, 1:3, 1:4, 3:2.5, 3:5, 3:10, 2:1, 6:2.5, 6:5, 6:10, 4:1, 5:6, 12:2.5, 12:5, or 6:5; it can also be any ratio between 2~15:2~12, preferably 3~12:2.5~10, and more preferably 3:2.5~10.

[0039] In some specific embodiments, the small-particle phosphonocarboxylic acid monovalent metal salt is small-particle sodium phosphonocarboxylate or small-particle potassium phosphonocarboxylate.

[0040] According to another aspect of the present invention, a method for preparing the above-mentioned phosphonoformic acid sustained-release formulation is also provided, comprising using calcium phosphonoformate as the active ingredient; or using calcium phosphonoformate and small-particle phosphonoformic acid monovalent metal salt as the active ingredients.

[0041] Calcium phosphonocarboxylate can delay the release of phosphonocarboxylate. Small-particle phosphonocarboxylate metal salts work together with calcium phosphonocarboxylate to maintain the uniform release of phosphonocarboxylate, maintain the concentration of phosphonocarboxylate in the vitreous cavity, and prolong the time for phosphonocarboxylate to exert its therapeutic effect.

[0042] In some specific embodiments, the active ingredient is also prepared by suspending it in triethyl acetyl citrate. ATEC causes the calcium or sodium phosphonoformate in the suspension to disperse very slowly outside the sustained-release formulation system, releasing phosphonoformic acid so that it is uniformly dispersed to the delivery site.

[0043] In some specific embodiments, the preparation method of the small-particle phosphonocarboxylic acid monovalent metal salt includes adding an aqueous solution of the phosphonocarboxylic acid monovalent metal salt dropwise to an antisolvent to precipitate the small-particle phosphonocarboxylic acid monovalent metal salt. In some specific embodiments, the solubility of the aqueous solution of the phosphonocarboxylic acid monovalent metal salt in the preparation of the small-particle phosphonocarboxylic acid monovalent metal salt is ≤10 mg / mL.

[0044] The solubility of the phosphonocarboxylic acid monovalent metal salt aqueous solution can be, but is not limited to, 1 mg / mL, 2 mg / mL, 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL or 10 mg / mL, or any value between 1 and 10 mg / mL, preferably 5 mg / mL.

[0045] In some specific embodiments, the preparation of small-particle phosphonocarboxylic acid monovalent metal salts further includes filtration and drying after precipitation to obtain small-particle phosphonocarboxylic acid monovalent metal salt solids. In some specific embodiments, the antisolvent includes anhydrous ethanol.

[0046] According to another aspect of the present invention, the use of the above-described phosphonoformic acid sustained-release formulation or the phosphonoformic acid sustained-release formulation prepared by the above-described preparation method in the preparation of a medicament for the prevention / treatment of viral retinal diseases is also provided.

[0047] In some specific embodiments, the drug includes a sustained-release drug; in some specific embodiments, the drug is administered via topical ocular administration; in some specific embodiments, the topical ocular administration includes at least one of intravitreal injection, intravitreal sustained-release implantation, continuous anterior chamber perfusion, or intracapsular implantation; in some specific embodiments, the drug dosage form includes at least one of injection, microcapsule, intravitreal implant tablet / rod, sustained-release plug, microneedle patch, in-situ gel, or nanospheres.

[0048] The viral retinal disease includes retinal diseases caused by viral infection, including but not limited to at least one of varicella-zoster virus, herpes simplex virus (type 1 and type 2), cytomegalovirus, or Epstein-Barr virus.

[0049] Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0050] The reagents, consumables and instruments involved in the following examples are shown in Table 1.

[0051] Table 1

[0052] Preparation of calcium phosphonate: 1) Add 2 mg / mL sodium phosphonate aqueous solution dropwise to 2 mg / mL calcium chloride solution under magnetic stirring; 2) After the solid has settled sufficiently, discard the supernatant, dry it with a vacuum filter funnel, wash it with deionized water, repeat the vacuum filtration process several times, and dry it to obtain calcium phosphonate solid.

[0053] Preparation of small-particle sodium phosphonate: The preparation method, as shown in Table 2, specifically includes: slowly adding an aqueous solution of sodium phosphonate to anhydrous ethanol under magnetic stirring until small particles of sodium phosphonate precipitate; filtering with a vacuum funnel, washing with anhydrous ethanol, repeating the filtration cycle several times, and drying to obtain solid sodium phosphonate particles. It has been verified that sodium phosphonate aqueous solution concentrations of 0.1~10 mg / mL can be used for phosphonate sustained-release formulations, with 5 mg / mL showing the best effect.

[0054] Table 2

[0055] Example 1 Calcium phosphonate and sodium phosphonate particles were prepared and suspended in ATEC to prepare calcium phosphonate / ATEC suspension and sodium phosphonate / ATEC suspension, respectively, for in vitro verification of the sustained-release effect of phosphonate. The specific procedures are as follows:

[0056] 1. In vitro dispersion effect Add the calcium phosphonate / ATEC suspensions and sodium phosphonate / ATEC suspensions of each concentration shown in Table 3 to 100 μL of PBS, let stand at room temperature, and observe their dispersion.

[0057] Table 3

[0058] After adding calcium phosphonate / ATEC suspension and sodium phosphonate / ATEC suspension to PBS, respectively, the turbidity was observed after standing at room temperature for 30 min, 3 h, 24 h, and 48 h. The state of each suspension in PBS at 30 min and 48 h is shown in the figure. Figure 1 and Figure 2 As shown, the PBS solution gradually became turbid, indicating that calcium phosphonate or sodium phosphonate in different suspensions dispersed very slowly into the PBS solution. After 48 hours, white solid calcium phosphonate or sodium phosphonate suspended in ATEC was still present at the bottom of the tube.

[0059] 2. Foscarboxylic acid release effect The calcium phosphonate / ATEC suspensions and sodium phosphonate / ATEC suspensions of various concentrations shown in Table 4 were added to 100 μL of PBS and allowed to stand at room temperature. The concentration and percentage of phosphonate released in PBS were measured at 10 min, 30 min, 1 h, 3 h, 24 h, 48 h, 1 w, 2 w, 3 w, 4 w, and 5 w, respectively.

[0060] Table 4

[0061] The results are as follows Figure 3 and Figure 4 As shown, the concentration and percentage of phosphonoformic acid released from 2.5 mg and 10 mg sodium phosphonoformate reached their maximum at week 4 and began to decline at week 5. The concentration and percentage of phosphonoformic acid released from 5 mg sodium phosphonoformate reached their maximum at week 3 and began to gradually decline at weeks 4 and 5. The trend of phosphonoformic acid release from sodium phosphonoformate was 10 mg% > 2.5 mg% > 5 mg%. Figure 5 As shown, the concentration and percentage of phosphonoformic acid released from 3 mg, 6 mg, and 12 mg calcium phosphonoformate continued to increase over time, indicating a slow and gradual release. The trend of phosphonoformic acid release from calcium phosphonoformate was 3 mg% > 6 mg% > 12 mg%.

[0062] Example 2 1. Experimental Objective: Two healthy New Zealand white rabbits were selected as research subjects for this experiment. The aim was to evaluate the safety of a 10% calcium phosphonate suspension containing triethyl acetylglucosamine in the rabbit eyes and to detect the concentration of phosphonoformic acid in serum and aqueous humor at different time points.

[0063] 2. Experimental Procedure: The appearance, inflammatory response, and fundus condition of both eyes in two rabbits were observed at different time points after intravitreal injection. The time points included immediately after injection, day 18, and day 30.

[0064] 3. Results: 1) such as Figure 6 and Figure 7 As shown, a white solid was observed in the eye immediately after injection. By day 18, the white substance was present in the vitreous cavity of both rabbits' eyes after injection, and the retina could be photographed without obvious refractive media opacity; however, as time went on, the white substance in the vitreous cavity of both rabbits' eyes showed a decreasing trend.

[0065] 2) such as Figure 8 As shown, by day 30, rabbit #1 had a larger area of ​​white substance in the fundus of the treated eye, while rabbit #2 had a smaller area of ​​white substance in the fundus of the treated eye, both of which were sensitive to light reflection; by day 42, the situation was similar to that on day 30.

[0066] 3) The results of phosphonocarboxylic acid concentration detection in aqueous humor and serum are shown in Table 5. In rabbit No. 1, phosphonocarboxylic acid in the aqueous humor of the treated eye was at the lower limit of detection on day 18, while in rabbit No. 2, phosphonocarboxylic acid was still detectable even on day 30, and the concentration of phosphonocarboxylic acid in the aqueous humor showed an increasing trend over time. At all detection time points, phosphonocarboxylic acid was not detected in the serum of either rabbit No. 1 or No. 2.

[0067] Table 5

[0068] In Table 5, "BQL" indicates below the detection limit. " / " indicates no detection.

[0069] Example 3 1. Experimental Objective: Nine healthy New Zealand white rabbits were selected as research subjects to evaluate the safety of triethyl acetylglucosyl citrate suspensions with different solid contents of sodium phosphonoformate and 3 mg calcium phosphonoformate, as well as sodium phosphonoformate triethyl acetylglucosyl citrate suspensions, on rabbit eyes, and to detect the concentration of phosphonoformic acid in the aqueous humor of both eyes at different time points.

[0070] 2. The experimental protocols for intravitreal injection of sodium phosphonate with different solid contents and 3 mg calcium phosphonate mixed with acetylsicitrin triethyl citrate, as well as sodium phosphonate triethyl citrate suspension, are shown in Table 6.

[0071] Table 6

[0072] In Table 6, “ / ” indicates that no injection or medication was administered.

[0073] 3. Experimental Procedure The appearance and inflammatory response of the treated eye in two rabbits were observed at different time points after intravitreal injection (day 1, day 3, and day 7 after injection), and the concentration of phosphonoformic acid in the aqueous humor of both eyes of the rabbits was measured at different time points.

[0074] 4. Experimental Results 1) By day 3, except for rabbit number 9 which had eyelid redness and corneal edema in the treated eye, the treated eyes of other rabbits were normal, constricted in response to light, closed in response to light, and had white material in the vitreous cavity.

[0075] 2) By day 7, the pupils of rabbits 3-7 that received the drug initially were large, constricted when exposed to light, and closed when exposed to light, with white material in the vitreous cavity; rabbit 8 had small pupils in both eyes initially, with white material adhering to the pupils, and did not constrict when exposed to light, and closed when exposed to light; rabbit 9 had red and swollen eyelids and corneal edema in the eyes that received the drug, and slightly closed when exposed to light; no white material was found in the eyes of rabbits 10 and 11 that received the drug subconjunctival injection; rabbit 11 had medium-sized pupils initially, with white material adhering to the pupils, and did not constrict when exposed to light, did not close when exposed to light, and had white material in the vitreous cavity.

[0076] 3) The concentration of phosphonic acid in the aquarium water of New Zealand white rabbits at different times is shown in Table 7.

[0077] Table 7

[0078] In Table 7, "BQL" indicates a value below the detection limit.

[0079] The results showed that, except for rabbit number 9, which had more severe ocular inflammation (treatment: application of ofloxacin eye ointment for 9 days) and died on day 14 (e.g. Figure 9 As shown, rabbit number 9 had normal fundus in both eyes, and its cause of death was unrelated to the medication (it was likely due to eye inflammation causing it to stop eating). Apart from this, no other animals showed any serious adverse reactions.

[0080] Example 4 1. Experimental Objective: Three healthy, washed-out New Zealand white rabbits were selected as research subjects. The aim was to evaluate the safety of a suspension containing 40 mg calcium phosphonoformate in triethyl acetylglucosyl citrate for rabbit eye administration, to detect the concentration of phosphonoformate in the aqueous humor of the rabbit eye at different time points, and to obtain the histopathological results of the rabbit eye tissue.

[0081] 2. The experimental protocol for intravitreal injection of 40 mg calcium phosphonate in triethyl acetylglucosyl citrate suspension is shown in Table 8.

[0082] Table 8

[0083] In Table 8, " / " indicates that no injection or medication was administered.

[0084] 3. Experimental Procedure: The appearance, inflammatory response, and presence of white material in the fundus of the treated eyes of two rabbits were observed at different time points after intravitreal injection (days 1, 5, 10, 30, 60, 100 and the day of euthanasia). The concentration of phosphonoformic acid in the aqueous humor of the treated eyes was also measured at different time points.

[0085] 4. Results 1) such as Figure 10 As shown, from the time of administration until day 10, the treated eyes of the three rabbits showed sensitive light reflex, normal pupils, and light constriction, with white material visible in the fundus; on day 30, white phosphonoformate precipitate was still observed in the fundus of the rabbits. Except for rabbit number 4, which was euthanized on day 23 due to its eyes being bitten and its poor condition, the treated eyes of the other two rabbits were normal; on day 60, the remaining two rabbits showed rapid light reflex and closure of the treated eyes, normal pupils, and light constriction, with white material still visible in the fundus; as... Figure 11 As shown, on day 100, the remaining two rabbits showed rapid blinking and pupillary contraction in the treated eye, normal pupillary light reflex, and visible white material in the fundus. The area of ​​the white material had decreased compared to before, but it was still present. In rabbit number 6, the white material in the fundus had slightly spread out. Figure 12 As shown, on day 226, rabbit #3 had a slightly slower pupillary closing when exposed to light, normal pupil size, slow constriction when exposed to light, and no white material was observed in the fundus of the treated eye; rabbit #6 had a slow pupillary closing when exposed to light, normal pupil size, obvious constriction when exposed to light, and a large amount of white material was visible in the fundus of the treated eye.

[0086] As time progressed, the concentration of phoscarboxylic acid in the aqueous humor of the treated eyes of rabbit #3 generally showed a decreasing trend. Although the concentration of phoscarboxylic acid in the aqueous humor increased from day 5 to day 100 between days 30 and 100, it was still lower than the concentration of phoscarboxylic acid in the aqueous humor 24 hours after administration. The concentration of phoscarboxylic acid in the aqueous humor of the treated eyes of rabbit #6 showed a decreasing trend before day 60, but from day 100 to day 226, the concentration of phoscarboxylic acid in the aqueous humor increased to or even higher than the concentration of phoscarboxylic acid in the aqueous humor 24 hours after administration. This may be related to the fact that a large amount of white substance could still be observed in the treated eyes of rabbit #6 on day 226.

[0087] 2) such as Figure 13 As shown, histopathological results revealed that the retinal pathology of the two rabbits that received intraocular injections of 40 mg calcium phosphonate was normal, and no material residue was found in the eyes, which most likely escaped from the eyes during the gradient dehydration process.

[0088] Up to the day the rabbits were euthanized, intravitreal injection of calcium phosphonate did not cause any significant adverse reactions in the rabbits' eyes.

[0089] 3) The aqueous humor test results of the three rabbits at different times are shown in Table 9.

[0090] Table 9

[0091] "BQL" indicates below the detection limit; "NA" indicates not obtained.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A phosphonocarboxylic acid sustained-release formulation, characterized in that, The active ingredients include calcium phosphonate, or calcium phosphonate and small-particle monovalent metal salts of phosphonate; The particle size of the small-particle phosphonocarboxylic acid monovalent metal salt is ≤14μm.

2. The phosphonocarboxylic acid sustained-release formulation according to claim 1, characterized in that, It also includes triethyl acetyl citrate, wherein the active ingredient is suspended in triethyl acetyl citrate.

3. The phosphonoformic acid sustained-release formulation according to claim 1 or 2, characterized in that, The mass ratio of calcium phosphonoformate to small-particle monovalent metal salt of phosphonoformate is 2~15:2~12.

4. The phosphonocarboxylic acid sustained-release formulation according to claim 3, characterized in that, The mass ratio of calcium phosphonoformate to small-particle monovalent metal salt of phosphonoformate is 3~12:2.5~10.

5. The phosphonocarboxylic acid sustained-release formulation according to claim 3, characterized in that, The mass ratio of calcium phosphonoformate to small-particle phosphonoformate monovalent metal salt is 3:2.5~10.

6. The phosphonocarboxylic acid sustained-release formulation according to claim 1, characterized in that, The small-particle phosphonocarboxylic acid monovalent metal salt is small-particle sodium phosphonocarboxylate or small-particle potassium phosphonocarboxylate.

7. The method for preparing the phosphonoformic acid sustained-release formulation according to any one of claims 1 to 6, characterized in that, Including those with calcium phosphonate as the active ingredient; or, The active ingredients are calcium phosphonate and small-particle monovalent metal salts of phosphonate.

8. The preparation method according to claim 4, characterized in that, It also includes preparations made by suspending the active ingredient in triethyl acetyl citrate.

9. The preparation method according to claim 7 or 8, characterized in that, The method for preparing the small-particle phosphonocarboxylic acid monovalent metal salt includes adding an aqueous solution of the phosphonocarboxylic acid monovalent metal salt dropwise into an antisolvent to precipitate the small-particle phosphonocarboxylic acid monovalent metal salt; Preferably, in the preparation of small-particle phosphonocarboxylic acid monovalent metal salt, the solubility of the phosphonocarboxylic acid monovalent metal salt aqueous solution is ≤10mg / mL, preferably 5mg / mL; Preferably, the preparation of small-particle phosphonocarboxylic acid monovalent metal salt further includes filtration and drying after precipitation to obtain small-particle phosphonocarboxylic acid monovalent metal salt solid; Preferably, the antisolvent comprises anhydrous ethanol.

10. The use of the phosphonocarboxylic acid sustained-release formulation according to any one of claims 1 to 6 or the phosphonocarboxylic acid sustained-release formulation prepared by the preparation method according to any one of claims 7 or 8 in the preparation of a medicament for the prevention / treatment of viral retinal diseases; Preferably, the drug comprises a sustained-release drug; Preferably, the method of administration of the drug includes topical ocular administration; Preferably, the local ocular drug delivery includes at least one of intravitreal injection, intravitreal sustained-release implantation, continuous anterior chamber perfusion, or intracapsular implantation. Preferably, the dosage form of the drug includes at least one of the following: injection, microcapsule, intravitreal implant tablet / rod, sustained-release thrombus, microneedle patch, in-situ gel, or nanosphere.

Images