JP2000143538A - Pharmaceutical composition containing immunomodulating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an administration style of an immunomodulating agent effectively developing the drug action while suppressing the systemic absorption of the drug to avoid the side action even in a case of the presence of the seat of an immune disease on a part other than the mucosa and body surface where the direct application of drug is possible and enabling easy oral or parenteral administration by the patient himself. SOLUTION: This pharmaceutical composition contains an immunomodulating agent as an active component and is effective for the therapeutic treatment, relapse suppression and prevention of immune diseases by oral or parenteral administration. The immunomodulating agent is selectively taken in the digestive tract immune tissue or a macrophage existing in the tissue.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention is designed to contain an immunomodulator and suppress its dissolution or release in the digestive tract, so that macrophages present in the digestive tract immune tissue can be selectively absorbed. It relates to a pharmaceutical composition. More specifically, the present invention comprises an immunomodulator such as corticosteroid, which causes a problem when administered systemically, and effectively and selectively provides an immunomodulator to macrophages present in the digestive tract immune system. And a pharmaceutical composition capable of effectively treating or preventing immune diseases such as idiopathic inflammatory bowel disease with less systemic side effects.

[0002]

2. Description of the Related Art Corticosteroids, azathioprine,
BACKGROUND ART Immunomodulators such as cyclosporine have been used for the treatment of autoimmune diseases and allergic diseases. However, while therapeutic effects can be expected, their use is limited due to their strong side effects. Therefore, corticosteroids are used for rhinitis, asthma,
For diseases such as dermatitis and colitis, it is administered directly to the diseased area by devising a dosage form such as the respiratory tract mucous membrane, skin, and rectum to express the effects of corticosteroids, and then becomes inactive as absorption from the affected area progresses A technique called ante drug that is rapidly converted to metabolites (Drugs (1995); Vol. 50; No.
5; 854-872) has already been commercialized. However, in this case, the indications are limited to those in which the drug can be directly administered to the affected area, and there is no application example of an antidrug to immunomodulators other than steroids. For intravenous injections, a drug that has a therapeutic effect to some extent for rheumatoid arthritis has been put into practical use as a delivery system in which a steroid is encapsulated in a colloidal preparation such as a fat emulsion (Advanced Drug Delivery Reviews). (1996); Vo
l.20; 195-201). However, intravenous injections cannot be frequently administered, and there are also problems in terms of convenience and compliance. Therefore, even when there is a lesion other than on the mucous membrane or the body surface, it is possible to avoid the systemic side effects while effectively exhibiting the medicinal effect, and to be able to easily administer orally or enterally by the patient himself. There is no dosage form of the immunomodulator yet.

[0003] Next, sustained-release injections using biodegradable and absorbable polymers such as polylactic acid have been put to practical use with leuprolide acetate as the main drug (Pharm Tech Japan (1)
998); Vol.14; 75-88) In the field of microspheres (or nanospheres, microcapsules, nanocapsules, etc.), microspheres are used for the systemic delivery of low-absorbing drug substances such as peptides and proteins. Fundamental attempts have been made to use it as a carrier, as a vaccine or as a base for oral tolerance, to promote the absorption of drugs from the gastrointestinal tract. However, when targeting systemic absorption of peptides and proteins, its low efficiency is still a problem, and this is also the limit of the carrier itself. But the result is the same (Nature (1997); Vol.386; 410-4
14) The technology that can withstand practical use has not yet been completed.
On the other hand, regarding the use of microspheres targeting the gastrointestinal tract immune system, see Vaccine (1996); Vol. 14; 167
Its effects are being confirmed in oral vaccines as described in 7-1685 and Japanese Patent No. 27471728 or in trials of oral tolerance.

[0004] Under such circumstances, few attempts have been made to supply low molecular drugs to macrophages and the like present in the digestive tract immune system. For example, it has been reported that the use of nanoparticle preparations for both the intravenous injection and oral administration of the anti-AIDS drug azidothymidine increases the accumulation on macrophages as compared to solution preparations (AIDS Research and Human Retrovirus).
es (1996); Vol. 12; No. 18; 1709-1715), and the magnitude of its pharmacotherapy utility is not specifically described. In addition, a report was made on the preparation of nanoparticles based on polycaprolactone for cyclosporin A, a clinically used immunomodulator, with the aim of improving bioavailability and avoiding side effects from the oral route. (Journal of Pharmaceutical Scie
nces (1996); Vol.85; No.2; 206-213) On the other hand, intramuscular injection of cyclosporin A encapsulated in microspheres with polylactic acid and having an average diameter of 260 nm can reduce blood concentration by the principle of molecular sieving. It has also been reported that the concentration in the lymph can be maintained continuously high for at least one month without any increase (Biol. Pharm. Bull. (1996); Vo).
l.19; No.11; 1527-1529). However, from these two reports, the preferred administration of the immunomodulator cyclosporin A, which can avoid systemic side effects while effectively exhibiting its efficacy, and can be easily administered orally or enterally by the patient himself. The form cannot be simply predicted. That is,
Whether the absorption from the oral route is high or low,
It is not yet clear what pharmacological utility the target tissue could have as lymph. It is generally accepted that in the case of low-molecular-weight drugs that have relatively good absorbability by the oral route, the use of microsphere technology to make the drug into particles reduces the absorption rate of the drug rather and makes the drug more effective. The notion of lack of control appears to be dominant, and confirmation by pharmacological experimental data is essential to demonstrate the benefits of this type of dosage form.

[0005] As described above, when microspheres are administered orally or enterally, they have not been sufficiently successful as a carrier for systemic drug absorption, and they target the gastrointestinal tract immune system. At present, sufficient utility has not been found experimentally other than vaccines and immunological tolerance even when used as carriers that have been used.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a systemic system which is effective even when an immunological disease lesion is present in a mucous membrane or a body surface other than the mucosa or body surface where the drug can be directly administered. Another object of the present invention is to provide a dosage form of an immunomodulator which can suppress side effects by suppressing the absorption of various drugs and can be easily orally or enterally administered by a patient himself.

The inventors of the present invention have conducted intensive studies in order to achieve the above object. As a result, the present inventors have found that they contain an immunomodulator and have an average particle size or a distribution range of main particles of 1 to 15 μm, and a gastrointestinal tract. Oral administration of a pharmaceutical composition in a particulate form in which dissolution or release of the immunosuppressant has been suppressed reduces the absolute amount of the immunomodulator absorbed into the body, but is present in the immune system of the gastrointestinal tract or at the relevant site The macrophage can selectively deliver the immunomodulator, resulting in effective therapeutic or preventive results in immunological diseases and systemic distribution of the immunomodulator (blood concentration) Has been found to be the index), and completed the present invention.

[0008]

That is, the present invention comprises an immunomodulator as an active ingredient, and is used for the treatment, prevention of recurrence or prevention of an immune disease when administered orally or enterally. A pharmaceutical composition, wherein the immunomodulator is selectively taken up by a gastrointestinal tract immune tissue or a macrophage present at the site.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The pharmaceutical composition of the present invention can maximize its effects when used for the treatment, prevention of recurrence or prevention of immune diseases. If an immunomodulator is taken in a general dosage form in order to maximize its effect, systemic tissues will be indiscriminately exposed to the immunomodulator and adverse effects will occur. While expression is a concern, the use of the particulate pharmaceutical composition of the present invention enables selective selection of immune system cells and immune tissues such as macrophages that play an important role in maintaining the pathology of immune diseases. Incorporation and subsequent release of the immunomodulator during the process of transferring to the systemic immune system such as the spleen, so-called targeting effect is obtained, and even if these particulate pharmaceutical compositions did not transfer to the immune system In this case, since the immunomodulator is excreted outside the living body before being released in the digestive tract, exposure of the systemic tissue to the drug can be reduced.

[0010] The particulate pharmaceutical composition having such characteristics is composed of particles such as microspheres, nanospheres, microcapsules, and nanocapsules, and is prepared as follows. For example, in the case of a poorly water-soluble drug in which the drug cannot be easily dissolved throughout the entire digestive tract, if the drug itself is finely pulverized or granulated, the surface activity such as Pluronic or cellulose lower alkyl ether is used. An agent which can be dispersed in gastrointestinal fluid by using an agent, or a drug which itself is formed into particles and then coated with a polymer material to form a film can be used.
As the polymer material used here, a biodegradable and absorbable polymer is a preferable material. The term "biodegradable and absorbable" as used herein means that when administered to humans or animals, it is hydrolyzed in the body, decomposed into water-soluble oligomers or monomers, and gradually disappears.
Accordingly, the particulate pharmaceutical composition of the present invention can be imparted with controlled release properties such that the drug is not easily dissolved or released, and it takes a certain period of time to release the drug.
Examples of the biodegradable and absorbable polymer used in the present invention include polylactic acid, polyglycolic acid, lactic acid-glycolic acid copolymer, polycaprolactone, polyhydroxybutyric acid, copolyoxalate, polycyanoacrylate, polycarbonate, and polyorthoester. And polyanhydrides. As these biodegradable and absorbable polymers, for example, commercially available ones can be used, and the Journal of Biomedical Materials Research (1.
988), Vol. 22, 837-858. That is, a polycondensation reaction is carried out at 180 ° C. under reduced pressure on each monomer or a monomer mixed at a fixed ratio under a catalyst-free condition, and the reaction product is chloroform or 1,1,1,3,3,3.
-Hexafluoro-2-isopropanol (HFIP)
And then adding methanol to precipitate the polyester to remove unreacted monomers and the like, followed by purification.

The pharmaceutical composition of the present invention may be a so-called microsphere in which an immunomodulator is dispersed in matrix-like particles containing the above-mentioned biodegradable and absorbable polymer as a main component. good. As biodegradable and absorbable polymers constituting the microspheres, polylactic acid, polyglycolic acid, lactic acid-glycolic acid copolymer polycaprolactone, polyhydroxybutyric acid, copolyoxalate, polycyanoacrylate, polycarbonate,
Polyorthoesters and polyanhydrides are preferred. The microspheres used here are obtained by drying a solution of a biodegradable and absorbable polymer and an immunomodulator, or a mixed dispersion such as an emulsion or suspension thereof in a liquid or spray drying. Can be prepared. In the in-liquid drying method, for example, in the case of a fat-soluble drug, a substance dissolved in methylene chloride or HFIP together with a biodegradable and absorbable polymer is added to an approximately 10-fold volume aqueous solution containing a surfactant, and emulsified. Microspheres can be obtained by completely evaporating the organic solvent while stirring at a temperature of 30 ° C. In the case of a hydrophilic drug, its aqueous solution is about 3
After emulsifying in advance in a solution of a biodegradable and absorbable polymer such as methylene chloride in a volume of 10 times or more to obtain a W / O emulsion, this is added to a surface active aqueous solution of about twice the volume of an organic solvent and added. Emulsification is again performed to obtain a W / O / W emulsion, and the organic solvent is evaporated while stirring this in an excessive amount of water to obtain microspheres. Examples of surfactants that can be used in the preparation of microspheres by the in-liquid drying method include polyvinyl alcohol. On the other hand, in the preparation by the spray drying method, microspheres can be obtained by directly spray drying a solution or a mixed dispersion of the biodegradable and absorbable polymer and the immunomodulator. The microspheres obtained by the submerged drying method or the spray drying method can be stored by washing with distilled water and freeze-drying.

[0012] The pharmaceutical composition of the present invention is prepared by controlling the conditions in the preparation step so as to obtain a composition having a certain particle size distribution, or performing a classification operation after preparation to prepare a composition having a certain particle size distribution. Can be sorted out. The particle size distribution of the particulate pharmaceutical composition of the present invention is 90% by weight or volume ratio.
% Or more is preferably in the range of 1 to 15 microns, and 90% or more by weight or volume ratio is 2 to 7 microns.
Particularly preferred is in the micron range. Thus, in order for the particulate pharmaceutical composition of the present invention to be more efficiently taken into the digestive tract immune tissue, it is necessary to control its particle size distribution preferably within the above-mentioned certain range,
Thereafter, it is phagocytosed by macrophages and translocates to a systemic immune system such as the spleen, and selectively develops its effect while releasing an immunomodulator during the process.

When the particulate pharmaceutical composition of the present invention is administered to humans or animals, there is no particular limitation on the specific form other than oral or enteral administration. For example, as oral preparations, take the dry form as it is, or fill it with capsules together with excipients and take it, or return the dry form to water once and disperse it before taking. Or you can. In addition, when enteral nutrition therapy is administered by feeding the gastrointestinal tract from the nostrils or the like, it is possible to administer it in such a way that it is mixed with the nutrient solution, or by using a form of suppository. It can also be administered directly to the rectum and the like.

The term "immunomodulator" as used in the present invention is defined as an agent capable of suppressing or modifying an excessive or abnormal immune response. The immunomodulator used in the present invention includes, for example, cortisone, hydrocortisone, triamcinolone, paramethasone, dexamethasone, betamethasone, prednisolone, beclomethasone, fluorometholone, budesonide,
Fluticasone and corticosteroids such as beclomethasone dipropionate, azathioprine, cyclophosphamide, cyclosporine, immunosuppressants such as tacrolimus, mizoribine, rapamycin and methotrexate, sodium gold thiomalate, D-penicillamine,
Disease-modifying antirheumatic drugs such as bucillamine, salazosulfapyridine, chloroquine and hydroxychloroquine can be mentioned. Of these, corticosteroids are preferred.

The immune disease of the present invention includes an autoimmune disease,
Includes allergic diseases, and rejection and graft-versus-host disease associated with organ transplants. Among them, autoimmune diseases include ulcerative colitis, Crohn's disease, rheumatic diseases such as rheumatoid arthritis, lupus erythematosus, systemic vasculitis,
Examples include polymyositis, multiple sclerosis, myasthenia gravis, interstitial pneumonia, psoriasis, uveitis and the like. Examples of the allergic disease include food allergy, atopic dermatitis, allergic rhinitis, bronchial asthma, chronic bronchitis and the like. Among them, the particulate pharmaceutical composition of the present invention, when administered for the treatment or prevention of inflammatory bowel disease consisting of ulcerative colitis and Crohn's disease, to maximize its effects, especially Can be.

The pharmaceutical composition of the present invention is preferably used as the active ingredient orally or enterally per adult daily, preferably 0.001 to 1.0, depending on the type and condition of the immunological disease or the condition of the patient. 100 mg, more preferably 0.0
1 to 10 mg is administered daily or intermittently.

[0017]

As described above, the present invention is designed to contain the immunomodulator of the present invention, inhibit its dissolution or release in the digestive tract, and selectively absorb macrophages present in the digestive tract immune tissue. By administering orally or enterally the obtained pharmaceutical composition in the form of particles and using it for the treatment or prevention of immune diseases, systemic drug administration can be carried out without diminishing the original effect of the immunomodulator. The side effect can be avoided by suppressing the distribution.

[0018]

EXAMPLES The present invention will be described below with reference to examples.

Example 1 (1) Poly-D, L-lactic acid (PDLLA) was synthesized by polycondensing D, L-lactic acid at 180 ° C. under reduced pressure in the absence of a catalyst. After the obtained PDLLA was purified, the molecular weight was measured by liquid chromatography, and as a result, the average molecular weight was 5,600.

(2) PDLLA microspheres containing dexamethasone sodium phosphate (DEX) were prepared by drying a double emulsion in liquid. 3.3 mg / ml DEX aqueous solution (aqueous phase 1: W1)
0.3 ml was added to 1 ml of methylene chloride solution (oil phase: O) in which 100 mg of PDLLA was dissolved, and emulsified by a probe sonicator to obtain a W1 / O emulsion. This emulsion was added as a surfactant to 2 ml of an aqueous solution (second aqueous phase: W2) containing 1% of polyvinyl alcohol having a polymerization degree of 1000 and a saponification degree of 87.7% and mixed with a vortex mixer to obtain W1. A double emulsion of / O / W2 was obtained. An aqueous solution containing 0.1% of polyvinyl alcohol in an amount of 100 m
methylene chloride was dried in the liquid while stirring at room temperature with a stirring blade at 200 revolutions / minute, and PEX containing DEX was added.
Microspheres containing DLLA as a main component were obtained.
The microspheres were washed three times in cold water at 4 ° C. and collected by centrifugation three times, and finally freeze-dried and stored until used in the evaluation experiment.

Example 2 (1) Female BALB / C mice weighing 20 to 25 g were used for preparing a colitis model administered with dextran sulfate (DSS). The mouse is 12
The animals were reared and fed freely under an hourly light-dark cycle. In the case of colitis, the first 7 days of drinking water are given an aqueous solution containing 5% (w / v) of DSS having a molecular weight of 5000, and the next 7 days are given normal water freely.
The disease was developed by repeating the four-day cycle two more times. The efficacy evaluation test was conducted by dividing 50 mice that developed colitis into the following 5 groups of 10 mice <[Example 2]
(2), [Comparative Example 1], [Comparative Example 2], [Comparative Example 3], [Comparative Example 4]>.

(2) Poly-D, L-lactic acid (PD) containing dexamethasone sodium phosphate (DEX) having an average particle size of about 4 μm and prepared by the method described in (2) of Example 1
LLA) Microspheres with a DEX amount of 0.1 m
g / kg and a PDLLA amount of 0.25 mg / Head was orally administered once a day for 14 days. On the 15th day, the mice were sacrificed under ether anesthesia and the large intestine was excised. Experimental Immunology (1997); V
ol. 107; 353-358, scored based on the histological criteria defined by Kojouharoff et al., and as an indicator of neutrophil infiltration, myeloperoxidase (MPO)
Activity and production of nitric oxide (NO) were measured. These results are summarized in Table 1.

Comparative Example 1 The DSS mouse prepared in Example 1 (1) was left untreated for 14 days in parallel with the administration schedule of Example 2 (2). On day 15, the mice were sacrificed under ether anesthesia, and the results of the tissue score, MPO, and NO measured by removing the large intestine were summarized in Table 1.

Comparative Example 2 According to the method (2) of Example 1, PDLLA-free microspheres containing no DEX were prepared using an aqueous solution containing no DEX. Example 2
Add the empty PDLL to the DSS mouse created in (1) above.
A microsphere once daily at 0.25 mg / Hea
d was orally administered for 14 days. On the 15th day, the mice were sacrificed under ether anesthesia, and the large intestine was excised to obtain a tissue score, MPO,
NO was measured. The results are summarized in Table 1.

[Comparative Example 3] DEX 0.1 mg / kg as an aqueous solution was added to the DSS mouse prepared in Example 2 (1).
Was orally administered once a day for 14 days. On the 15th day, the mice were sacrificed under ether anesthesia, the large intestine was excised, and the tissue score, M
PO and NO were measured. The results are summarized in Table 1.

Comparative Example 4 According to the method (2) of Example 1, PEXLA-free microspheres of DDLLA were prepared using an aqueous solution containing no DEX. Example 2
The DSS mouse prepared in (1) above was orally administered once a day with 0.25 mg / head of the empty PDLLA microsphere / 0.1 mg / kg of an aqueous solution of DEX simultaneously for 14 days. The animals were sacrificed under ether anesthesia, the large intestine was excised, and the tissue score, MPO, and NO were measured. The results are summarized in Table 1.

[Example 3] PDLLA microspheres containing DEX of Example 1 (2) were suspended in an isotonic phosphate buffer (PBS buffer) to prepare female BALB / C.
The mice were administered an oral sonde at a dose of 0.1 mg / kg in DEX amount, and were administered at 0, 30, 60, 90, 120, 15
After 0, 180 and 240 minutes under ether anesthesia 1-1.
5 ml of blood was collected (sacrificed after blood collection). The plasma was separated under cooling, and the plasma concentration of DEX was measured by reverse-phase HPLC. At each time point, the average of the two plasma concentrations was plotted on the graph in FIG.

[Comparative Example 5] DEX as a PBS buffer at a dose of 0.1 mg / kg was administered to female BALB / C mice via oral probe, and DEX was prepared in the same manner as in Example 3.
Was measured in plasma. As in Example 3, the mean of the plasma concentrations of the two animals at each time point was plotted in FIG.

[0029]

[Table 1]

All are experimental data of N = 10, and the numerical values are the average value ± standard error. (2) in Example 2 is the same as Comparative Examples 1 and 2 in all items of tissue score, MPO activity, and NO generation. Significantly low.
The values of MPO activity and NO generation were also lower than Comparative Examples 3 and 4. Comparative Examples 3 and 4 were significantly lower than Comparative Examples 1 and 2 in all items.

In each case, the average value of each point (N = 2) was plotted on the graph in the figure. In Comparative Example 5, the amount of 0.1 mg after administration was 0.
An increase in drug concentration in plasma was observed during 5-2.5 hours, whereas in Example 3, almost no drug was detected in plasma.

[Brief description of the drawings]

FIG. 1. Changes in plasma dexamethasone concentration after oral administration of dexamethasone and after administration of PDLLA containing dexamethasone

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) A61P 37/08 A61K 31/00 637E 37/04 637C A61K 47/34 47/34 C F-term (Reference) 4C076 AA32 AA65 AA67 AA95 BB01 BB05 CC07 EE13 EE24 EE48 FF03 FF25 FF32 FF68 4C084 AA17 AA27 MA05 MA38 MA41 MA52 MA60 NA06 NA12 NA13 ZA661 ZA662 ZA681 ZA682 ZB021 ZB022 ZB071 ZB072 ZB131

Claims (8)

[Claims] 1. A pharmaceutical composition comprising an immunomodulator as an active ingredient, which is used orally or enterally for the treatment, prevention or prevention of relapse of an immune disease. A pharmaceutical composition characterized in that the modulator is selectively taken up by the immune system of the gastrointestinal tract or macrophages present at the site. 2. The method of claim 1, wherein the immunomodulator is a microsphere;
2. The composition according to claim 1, which is contained in particles selected from nanospheres, microcapsules, and nanocapsules.
A pharmaceutical composition according to claim 1. 3. An in vivo organism wherein said particles have an average particle size or primary particle distribution range of 1 to 15 microns and are designed so that said immunomodulator is not readily dissolved or released in the gastrointestinal tract. The pharmaceutical composition according to claim 2, wherein a degradation-absorbable polymer is used. 4. The biodegradable and absorbable polymer is polylactic acid, polyglycolic acid, lactic acid-glycolic acid copolymer, polycaprolactone, polyhydroxybutyric acid, copolyoxalate, polycyanoacrylate, polycarbonate, polyorthoester. 4. The pharmaceutical composition according to claim 3, which is one or more selected from the group consisting of polyanhydrides and polyanhydrides. 5. The method according to claim 1, wherein the immunomodulator is a corticosteroid,
One or more selected from the group consisting of azathioprine, cyclophosphamide, cyclosporine, tacrolimus, mizoribine, rapamycin, methotrexate, sodium gold thiomalate, D-penicillamine, bucillamine, salazosulfapyridine, chloroquine, and hydroxychloroquine The pharmaceutical composition according to any one of claims 1 to 4, wherein 6. The method of claim 6, wherein the corticosteroid is cortisone, hydrocortisone, triamcinolone, paramethasone, dexamethasone, betamethasone, prednisolone,
The pharmaceutical composition according to claim 5, which is one or more selected from the group consisting of beclomethasone, fluorometholone, budesonide, fluticasone, and derivatives and salts thereof. 7. The pharmaceutical composition according to claim 1, wherein the immune disease is any one of an autoimmune disease, an allergic disease, graft rejection, and graft-versus-host disease. 8. The pharmaceutical composition according to claim 1, wherein the immune disease is an inflammatory bowel disease including ulcerative colitis and Crohn's disease.