JP3530542B2 - Argatroban formulation for ophthalmology - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel use of argatroban in the ophthalmic field. More specifically, the present invention relates to the use of the anterior chamber fibrin formation inhibitory effect of argatroban.

[0002]

BACKGROUND OF THE INVENTION Argatroban has the formula:

[Chemical 3] (2R, 4R) -4-methyl-1- [N ² -((R
S) -3-Methyl-1,2,3,4-tetrahydro-8
- a general name given to quinoline sulfonyl) -L- arginyl] -2-piperidinecarboxylic acid hydrate, the compound is N ² - belonging to arylsulfonyl -L- arginine amide.

Argatroban is disclosed in Japanese Patent Application No. 54-88786.
As described in the publication, it is a selective antithrombin substance having a completely new mechanism of action not found in conventional drugs. That is, the mechanism of action of argatroban includes selective inhibition of thrombin by sterically binding the three-leg structure of argatroban to the active site of thrombin. As a result, argatroban strongly inhibits the three main actions of thrombin: (1) fibrin production, (2) fibrin stabilization by activation of factor VIII, and (3) platelet aggregation. To do. As a result, it is known that argatroban can be clinically applied to improve limb ulcers, rest pain and cold sensation in chronic arterial occlusion.

The inventors of the present invention have paid attention to the above-mentioned unique mechanism of action of argatroban, and have earnestly studied applications of argatroban other than chronic arterial occlusion. As a result, the invention described in detail below has been completed. After intraocular surgery such as retinal and vitreous surgery, cataract surgery and glaucoma surgery, postoperative anterior chamber fibrin formation is often observed, which is extremely important to avoid postoperative management. Problem. For example, if fibrin formation occurs after surgery for inserting an intraocular lens, not only the prognosis of visual acuity deteriorates, but also there is a risk of developing a serious pathological condition such as complication of glaucoma. In addition, since fibrin formation after vitreous surgery makes postoperative fundus examination difficult, it interferes with appropriate treatment and treatment for fundus disease,
Furthermore, fibrin formation may also be responsible for the refractory condition of anterior retinal vitreous proliferation.

Under such circumstances, it was recognized that it is extremely important to prevent post-operative fibrin formation, but no means for appropriately performing it has been reported so far.

[0006]

Description of the Invention Argatroban has so far been administered for the purpose of preventing the formation of thrombus, which is a blood clot occurring in blood vessels. Therefore, the present inventors have examined whether or not argatroban can exert its original action in vivo other than in blood, and have been able to actually prevent fibrin formation after intraocular surgery. Was completed. Attempts to determine whether argatroban exhibits such an effect in vivo other than in blood have not yet been reported, and even the application of argatroban does not exist in the ophthalmological field.

[0007] Examples of the method of applying argatroban capable of preventing the formation of fibrin after intraocular surgery include direct administration in the anterior chamber, eyedrop administration, intravenous administration, and a method in which it is contained in the intraocular perfusate. . Intravenous administration is preferably performed by infusion. Furthermore, argatroban can be injected subretinally. The administration of argatroban may be performed before, during or after the operation.

Dosage forms used for the application of argatroban are liquids for parenteral administration, such as eye perfusion solutions, eye drops,
For example, a drug for drip. The ocular perfusion solution of the present invention can be produced by dissolving argatroban in sterile purified water or the like. At this time, pharmaceutically acceptable additives such as a tonicity agent, a buffering agent and the like, which are close to the composition of aqueous humor, can be added as necessary. Specifically, glucose, sodium chloride, potassium chloride, calcium chloride, magnesium sulfate, sodium hydrogen carbonate and the like can be added.

The eye drops of the present invention are aqueous eye drops, non-aqueous eye drops, suspension eye drops, and emulsion eye drops. The production of the eye drop of the present invention uses sterile purified water as an aqueous solvent, physiological saline or the like, or a vegetable oil such as cottonseed oil, soybean oil, sesame oil, peanut oil or the like as a non-aqueous solvent, and argatroban is dissolved or suspended in them. By. At this time, a tonicity agent, p
If necessary, pharmaceutically acceptable additives such as H regulators, thickeners, suspending agents, emulsifiers and preservatives can be added. Specific tonicity agents include sodium chloride, boric acid, sodium nitrate, potassium nitrate, D-mannitol, glucose and the like. As a pH regulator,
Examples thereof include boric acid, anhydrous sodium sulfite, hydrochloric acid, citric acid, sodium citrate, acetic acid, potassium acetate, sodium carbonate and borax. Examples of the thickener include methyl cellulose, hydroxypropyl methyl cellulose, polyvinyl alcohol, sodium chondroitin sulfate, polyvinyl pyrrolidone and the like. Examples of the suspending agent include polysorbate 80, polyoxyethylene hydrogenated castor oil 60, polyoxy hydrogenated castor oil, and the like. Examples of the emulsifier include egg yolk lecithin and polysorbate 80, and examples of the preservative include benzalkonium chloride, benzethonium chloride, chlorobutanol, phenylethyl alcohol, and paraoxybenzoic acid esters.

The infusion preparation of the present invention is an aqueous injection solution or an emulsion injection solution. The preparation of the infusion solution of the present invention uses distilled water for injection, physiological saline, Ringer's solution, etc. as a solvent,
Alternatively, it is carried out by using a small amount of a water-soluble organic solvent such as ethanol or a solvent containing glycerin and dissolving argatroban in them. At this time, pharmaceutically acceptable additives such as isotonicity agents, pH regulators, emulsifiers and preservatives can be added as necessary. Specific tonicity agents include sodium chloride, glucose, D-sorbitol, D-mannitol and the like. Examples of the pH regulator include anhydrous sodium sulfite, hydrochloric acid, citric acid, sodium citrate and the like. Emulsifiers include egg yolk lecithin and polysorbate 80, and preservatives include benzalkonium chloride, benzethonium chloride,
Paraoxybenzoic acid esters are mentioned.

As explained in the examples below, administration of argatroban into the anterior chamber at the same time as autologous plasma inhibited the formation of fibrin. This result indicates that transfer of argatroban to the anterior chamber can prevent fibrin formation in the anterior chamber. From these results, it is supported that argatroban can be applied by direct administration in the anterior chamber, and it is also considered that argatroban can inhibit fibrin formation after intraocular surgery by adding it to intraocular perfusate.
In addition, in the experiments using rabbits of the present inventors up to now,
Argatroban 10 μg / kg / min, 40 μg / kg / min, 4
By intravenous administration of 00 μg / kg / min, 5.7 ± 0.7, 41.0 ± 4.2, and 881 ± 110 respectively 1 hour after administration
An anterior chamber concentration of ng / ml was observed. In addition, when 2 mg / ml argatroban saline was instilled, 23.7 ±
An anterior chamber concentration of 19.1 ng / ml was obtained. This is
It is supported that intravenous administration and instillation also transfer argatroban into the anterior chamber, which may prevent fibrin formation in the anterior chamber.

The optimal dose of argatroban for humans depends on the administration method, administration time, patient age, symptoms, etc.
Can fluctuate. Generally, 1-50 mg / kg by intravenous administration
/ Day, and in the case of eye drops, argatroban 1 mg / ml-
Eye drops at a concentration of 6 mg / ml can be used. When added to the perfusate, the concentration of argatroban in the perfusate is 0.1 μg.
/Ml-0.6 mg / ml may be used.

[0013]

[Examples] Hereinafter, the inhibitory action of argatroban on fibrin formation in the anterior chamber will be described with reference to detailed examples. Thus, those skilled in the art will appreciate that the novel treatment methods of the present invention reduce fibrin formation after cataract surgery, vitreous surgery, and glaucoma surgery, resulting in a better visual outcome.

Example 1 Experimental model of fibrin formation in the anterior chamber by laser irradiation In this example, a model of fibrin formation in the anterior chamber of a rabbit by laser irradiation was used as a method for examining the action of argatroban. This model is also used as an eye inflammation model. According to this model, since the severity of inflammation and the amount of fibrin are determined in proportion to the total energy amount of laser irradiation, it is possible to adjust to the desired amount of fibrin by modifying the total energy amount of laser irradiation. it can. This time, two conditions of low irradiation energy (condition A) and high irradiation energy (condition B) were used, but stronger fibrin formation was observed in the eyes with high total irradiation energy.

Materials and Methods When irradiating an iris of a mature colored rabbit (body weight: 2 kg Dutch Rabbit) with an argon laser device (manufactured by NIDEK), a group of rabbits had a coagulation size of 50 μm.
Using a condition of m, output of 1.0 Watt, and irradiation time of 0.1 seconds (condition A), irradiation was carried out at eight points in a ring shape at equal intervals. Rabbits in another group were similarly irradiated at eight sites under the condition (coagulation size 200 μm, output 1.0 Watt, irradiation time 0.2 seconds) (condition B). Argatroban was intravenously administered from the ear vein at a dose of 0.1 mg / kg / min from 30 minutes before irradiation to 30 minutes after irradiation. Only the laser irradiation was performed for the control. As a positive control, heparin 1000 U / kg was intravenously injected 30 minutes before laser irradiation. As for the instillation, argatroban (5 mg / ml) was instilled in the right eye and the left eye was used as a control. The state of fibrin formation was photographed using a slit lamp microscope.

Further, after the laser irradiation under the above condition B, the anterior chamber flare value was measured using a flare cell meter 30 minutes and 60 minutes later.

Results In the control group, fibrin formation was observed after 30 minutes in both irradiation conditions A and B. The results obtained by the slit lamp microscope are shown in FIGS. 1 and 2 attached for Condition A and Condition B, respectively. In the positive control group (heparin administration group), fibrin formation was not observed during the observation period of 30 minutes to 3 hours after irradiation (results not shown). Even after the administration of argatroban at 0.1 mg / kg / min, fibrin formation was not observed at all in irradiation conditions A and B at 30 minutes after irradiation, as in the heparin administration group. The obtained results are shown in FIGS. 3 and 4 attached for Condition A and Condition B, respectively.

The results of the flare cell meter are shown in Table 1 below.
Shown in. The flare cell meter measures the turbidity in the anterior chamber as a light quantity count. Table 1 below shows that argatroban clearly inhibits fibrin formation after 30 and 60 minutes. Thus, the results of this experiment also supported the inhibitory effect of argatroban on fibrin formation in the anterior chamber.

[0019]

[Table 1] Effect of argatroban on increase of flare in anterior chamber after irradiation of colored rabbits with argon laser Light count (/ msec) Drug 30 minutes after laser irradiation 60 minutes after laser irradiation 877.0 ± 333.6 (n = 4) 1002.9 ± 137.0 (n = 4) IV argatroban IV 417.7 ± 159.3 (n = 4) 356.9 ± 168.3 (n = 4) argatroban eye drop 287.7 ± 99.2 (n = 4) 341.2 ± 86.5 (n = 4) Note: n = Number of individuals Argatroban IV = 0.1 mg / kg / min IV argatroban ophthalmic solution = Use a concentration of 5 mg / ml

Example 2 Experimental model of fibrin formation by intracameral administration of autologous plasma Blood of a mature white rabbit (body weight: 2 kg) was collected and plasma was separated to obtain plasma. From the same rabbit, 200 μl of anterior chamber water was collected by anterior chamber puncture, and then 150 μl of the obtained plasma and 50 μl of argatroban (10 mg / ml), 200 μl in total, were administered into the anterior chamber from the same puncture site. Control is plasma 150
μl and 50 μl of saline were similarly administered into the anterior chamber. The formation of fibrin in the anterior chamber was observed and recorded 24 hours after the administration. Results In the eye treated with argatroban in the anterior chamber, fibrin formation was not observed 24 hours after administration. In contrast, strong anterior chamber fibrin formation was observed in control eyes. The obtained results are shown in the attached FIGS. 5 and 6, respectively.

Observation As is clear from Examples 1 and 2 above, intravenous administration of argatroban completely inhibited fibrin formation in the anterior chamber of both the laser irradiation model and the autologous plasma injection model. This is probably because argatroban antagonized the action of thrombin in the process of converting fibrinogen to fibrin. Argatroban prevents the formation of thrombus and fibrin by its direct action on thrombin and does not act on other coagulation systems. Therefore, the risk of bleeding tendency after intraocular surgery is less than that of other anticoagulants such as heparin. Moreover, when the administration of argatroban is stopped, the coagulation function of the living body is promptly restored to normal. Thus, argatroban is considered to be an extremely effective and safe drug for clinical application in ophthalmology.

The toxicity data of argatroban are shown in Table 2 below.
Shown in.

TABLE 2 LD ₅₀ value of argatroban (mg / kg) animal intravenously intraperitoneally subcutaneously oral mice Male> 81 475 3750> 15000 Female> 81 640 3900> 15000 rat Male> 81 320 700> 15000 Female> 81 409 620 > 15000 dog male> 200 --- female> 200 ---

[Brief description of drawings]

FIG. 1 is a photograph instead of a drawing showing the morphology of an organism, showing the inside of the anterior chamber where fibrin is formed by laser irradiation under condition A.

FIG. 2 is a photograph instead of a drawing showing the morphology of an organism, showing the inside of the anterior chamber where fibrin is formed by laser irradiation under condition B.

FIG. 3 is a photograph instead of a drawing showing the morphology of an organism, showing the inside of the anterior chamber in which the fibrin formation in the anterior chamber due to laser irradiation of Condition A is inhibited by argatroban.

FIG. 4 is a photograph instead of a drawing showing the morphology of an organism, showing the inside of the anterior chamber in which fibrin formation in the anterior chamber due to laser irradiation of Condition B is inhibited by argatroban.

FIG. 5 is a photograph instead of a drawing showing the morphology of an organism, showing the inside of the anterior chamber in which fibrin formation by the intracameral administration of autologous plasma is inhibited by argatroban.

FIG. 6 is a photograph instead of a drawing showing the morphology of an organism, showing the inside of the anterior chamber where fibrin was formed by the intracameral administration of autologous plasma.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI C07D 215: 00) (58) Fields investigated (Int.Cl. ⁷ , DB name) A61K 31/47

Claims (5)

(57) [Claims] 1. The formula: In the anterior chamber, which contains argatroban as shown in
Ophthalmic agent for inhibiting ibrin formation . Wherein ophthalmic agent according to claim 1 for inhibiting fibrin formation in the anterior chamber after intraocular surgery. 3. The ophthalmic agent according to claim 2, wherein the intraocular surgery cataract, selected from nitric Solid surgery and glaucoma surgery. 4. The ophthalmic agent according to any one of claims 1 to 3 , wherein argatroban is directly administered into the anterior chamber. 5. The ophthalmic preparation according to claim 4 , which is administered by an administration method selected from an ocular perfusion solution, an eye drop, an intravenous administration and an infusion preparation.