JP2006280389A - Dds product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drug carrier without damaging the stability of a drug instable in a water environment and against heat and shearing force at the time of lyposome production, which can not be solved by well-known products like a drug carrier such as lyposome carrying the drug and a product of a type to be mixed when needed composed of lyophilized lyposome and medicine aqueous solution. <P>SOLUTION: This DDS product is provided with the stably preserved aqueous dispersion of the drug carrier and a stably preserved drug in a solid state, and the drug carrier carrying the drug is prepared by mixing the aqueous dispersion and the drug when needed. Especially, the DDS product is in a 2-chamber type prefilled syringe form in which the aqueous dispersion of the drug carrier and the drug are respectively housed so as to be mixed when needed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a DDS preparation in which a drug is carried on a drug carrier.

DDS preparations in which drugs are supported on drug carriers such as liposomes for the purpose of drug delivery, such as prolonging residence time in the blood and local targeting, are mainly used in the state of dispersions and dry preparations (eg freeze-dried preparations) It has been. In particular, when the stability of the drug is low, in order to ensure the stability of the drug, a dry preparation is prepared with the drug supported on the drug carrier. For example, since prostaglandins and the like are unstable in an aqueous environment, they are made into dry preparations as prostaglandins-liposome complexes, thereby improving storage stability. The dry preparation of the drug carrier is usually stored in a vial, and is administered after being dissolved in water for injection. There has also been proposed a kit preparation that can be mixed into a prefilled syringe having a dry preparation of a drug carrier and two chambers of water for injection, and can be easily mixed for administration (Patent Document 1: JP-A-5-139777). Issue gazette).
However, in the dry preparation of a drug carrier, heat and mechanical shearing force are generated in production. The drug selection range is also limited by the stability in these manufacturing conditions. In the case of drugs that are particularly unstable in the water environment, destabilization in the water environment during production cannot be avoided. Even if this is used as a pre-filled syringe as it is, it will not solve the problem. Among these limitations, dry drug carrier formulations still have a narrow selection of drugs.

On the other hand, lyophilized empty liposomes (FDEL method) are known as lyophilized preparations of liposomes known as drug carriers. In this method, an aqueous solution of drug is added to lyophilized empty liposomes to obtain liposomes that retain the drug at a high rate. Freeze solutions of proteins, peptides, and nucleic acids that are weak against heat and mechanical shearing force. It can be prepared for use by adding to dry empty liposomes (Non-patent Document 1: New development of drug delivery system).
When encapsulating drugs in freeze-dried empty liposomes (FDEL method), it is advantageous in that it retains proteins, peptides, nucleic acids, etc. that are weak against heat and mechanical shearing force. Specifically, in the case of a freeze-dried drug), it is necessary to perform an operation of once dissolving in water for injection or the like and then adding it to freeze-dried empty liposomes.

JP-A-5-139777 New development of drug delivery system (issued in October 2004, by Tsuneji Nagai, CMC Publishing)

  These current situations listed above are the means that are being worked on to solve the problems of drug carriers and drugs, but while expanding the range of drug selection, it still remains one major limitation in drug selection in drug carrier development. Therefore, a means to solve it is anxious. In view of such circumstances, an object of the present invention is to provide a drug carrier without impairing the stability of an unstable drug in an aqueous environment.

In order to solve the above problems, the present invention provides the following (1) to (5).
(1) A drug carrier carrying a drug dispersion having a stably stored aqueous drug carrier and a solid drug stably stored, and carrying the drug by mixing the aqueous dispersion and the drug A DDS formulation in which the body is prepared.
(2) Isolation means in which the aqueous dispersion of the drug carrier is filled in the first chamber of the container and the drug is filled in the second chamber of the container, and the first chamber and the second chamber can communicate with each other. The DDS preparation according to the above (1), which has the container isolated by (1).
(3) The DDS preparation according to (2), wherein the container is a two-chamber prefilled syringe.
(4) The DDS preparation according to any one of (1) to (3), wherein the drug carrier is a liposome.
(5) The DDS preparation according to (4), wherein the liposome is charged and adsorbs a drug on the surface thereof by electrostatic interaction during mixing.
(6) In the above (4) or (5), the liposome has a pH gradient between the inner and outer aqueous phases, and thereby allows the drug to be efficiently retained in the inner aqueous phase during ergonomic mixing. The DDS formulation as described.

The preparation provided by the present invention comprises an aqueous dispersion of a drug carrier and a solid state drug (especially a dry preparation), and a DDS preparation in which a drug carrier carrying a drug is prepared by mixing them carefully. Therefore, it is possible to avoid destabilization that occurs when a drug that is unstable in an aqueous environment is produced as a drug carrier, and to ensure stability until just before mixing in a lyophilized powder state. Therefore, a wide variety of drugs can be used without being restricted during preparation. Moreover, the DDS formulation which can be made into a state which can be administered by simple operation by providing as a kit formulation is provided. Furthermore, by making the drug carrier in the form of an aqueous dispersion and making it into a kit formulation, the drug carrier can be an alternative to the drug solution that was also required in the conventional dry preparation, It is possible to prepare a drug carrier by operation.

  Hereinafter, the present invention will be described in more detail. The aqueous dispersion of the drug carrier and the drug of the present invention are stored and stored in a container for independent and stable storage. Each container is preferably impermeable to water vapor and impermeable to gas such as oxygen, if necessary, so that each container can be stably stored. In the case where it has a property that is easily affected by light, it is preferably light non-transparent, particularly ultraviolet non-transparent. Both of them may be stored in a vial or the like and mixed by performing a mixing operation using a business syringe or the like. In addition, the convenience of this invention increases by making a storage preservation | save form into what is called a kit form. In the present invention, the “kit formulation” refers to a pharmaceutical preparation for daily use that has been developed from the viewpoints of simplifying the work of medical staff and preventing drug mix-up. Kit preparations include Mix-O-Vial, a type of double-chambered vials, Min-I-Jet, a type of Prefilled Disposable Syringes, and ADD-Vantage, a set of glass vials and soft bags with dedicated adapters. There are forms such as Frozen Premixes in which the system and the dissolved drug are frozen, or a double bag type formulation in which the inner space of the soft bag is a partition wall that can be communicated with each other by a weak seal between the inner surfaces of the bag.

Hereinafter, in the kit preparation, the room containing the aqueous dispersion of the drug carrier is referred to as the first room, and the room containing the medicine (drug) is referred to as the second room. The first chamber and the second chamber may be independent containers as described above, or the first chamber and the second chamber are formed with one container being separated by a partition wall or the like. It may be. A preferred embodiment of the present invention is a kit preparation that can be mixed with the drug in the second chamber using an aqueous dispersion of the drug carrier in the first chamber. More preferably, it is a kit preparation having a container formed in a state where the first chamber and the second chamber are separated from each other by a partition wall or the like capable of communicating with each other in one container. Specific examples of such a kit preparation include a two-chamber prefilled syringe in which a first chamber and a second chamber formed in a syringe outer cylinder are separated by a partition wall such as a gasket so that they can communicate with each other. Examples include a double bag type soft bag in which the chamber and the second chamber are separated by a partition wall formed of a weak seal formed on the inner surface of the bag so as to be able to communicate with each other.
The effect of the kit preparation of the present invention can be expected particularly when the drug is an unstable drug in an aqueous environment. The reason is that, due to the characteristics of the structure of the present invention, the chance that the drug is destabilized in the water environment can be extremely suppressed.

As an example of the container constituting the kit preparation of the present invention, there is a kit preparation provided with a two-chamber prefilled syringe whose cross-sectional view is shown in FIG. FIG. 2 is a cross-sectional view taken along line aa of the kit preparation provided with the two-chamber prefilled syringe shown in FIG.
The two-chamber prefilled syringe 10 is disposed in the outer cylinder 8, which is formed of a cylindrical body having a front end opening and a rear end opening capable of discharging the contents sealed in a liquid-tight manner by the cap 6. The distal end embolus 4 and the rear end side embolus 3 and a pusher 7 connected to the rear end of the rear end side embolus 3 are configured. In a space (second chamber) from the inner surface of the distal end of the outer cylinder 8 to the distal end of the distal end embolus 4, a medicine 2 to be described later is stored, and a space from the rear end of the distal end side embolus 4 to the distal end of the rear end side embolus 3 ( In the first chamber, an aqueous dispersion 1 of a drug carrier to be described later is stored. The outer cylinder 8 is provided with a side path 5 along the inner surface axial direction of the outer cylinder 8 so as to be slightly longer than the distal end-side embolus 4 from the distal end side to the thickness of the distal-end embolus. This side path 5 is a groove on the inner surface of the outer cylinder 8, and as shown in FIG. 2, after forming a normal outer cylinder having a smooth inner surface, the side wall of the outer cylinder is recessed from the inner surface side of the outer cylinder 8. Further, a groove may be formed by raising the corresponding outer cylinder 8 to the outer surface side, and convex portions and concave portions having shapes corresponding to the side surfaces of the inner and outer molds used when the outer cylinder 8 is injection-molded. It is also possible to form a groove constituting the side path 5 by providing it. In addition, after forming a normal outer cylinder having a smooth inner surface, it may be formed by cutting a groove forming the side path 5.

  The outer cylinder 8 is preferably hard and transparent so that the inner state can be visually recognized. The outer cylinder 8 is formed of glass, polypropylene, polyethylene, cyclic polyolefin, poly-4-methylpentene, vinyl chloride. Resin, polyethylene terephthalate, polyethylene naphthalate, polyetheretherketone, and the like can be used. However, when transparency is not required, a metal such as stainless steel may be used as the forming material. Of these, glass, polypropylene, and cyclic polyolefin are preferable from the viewpoints of drug non-adsorption and chemical resistance. The rear end side embolus 3 and the front end side embolus 4 define a first chamber and a second chamber, and impart liquid tightness and slidability to the inner surface of the outer cylinder 8. As the forming material of the rear end side embolus 3 and the front end side embolus 4, in addition to synthetic rubbers such as isoprene rubber and butyl rubber, styrene elastomers such as SEBS, SEPS, SEPE, SIS, SBR, or hydrogenation of those styrene elastomers And olefin-based elastomers such as ethylene-α-olefin copolymers, and resin compositions in which resins such as polypropylene and polyethylene are blended with these. The cap 6 liquid-tightly seals the tip opening of the outer cylinder 8, and the synthetic rubber, various elastomers, or synthetic resins such as polypropylene and polyethylene can be used as a forming material. The pusher 7 transmits a pressing force to the rear end side embolus 3, and is preferably formed of a hard material. As a material for forming the presser 7, various materials exemplified in the outer cylinder 8 can be used.

  Next, a method for using a kit preparation using such a two-chamber prefilled syringe 10 as a container will be described. First, the cap 6 that seals the distal end opening of the outer cylinder 8 is removed to expose the distal end opening, or the cap 6 is loosened, so that the second chamber can be evacuated. At this time, an injection needle (not shown) may be attached to the tip opening. Next, when the front end of the two-chamber prefilled syringe 10 is directed upward and the pusher 7 is pressed toward the front end of the syringe, the aqueous dispersion of the drug carrier in the first chamber filled together with the rear end side embolus 3. 1 and the distal end embolus 4 move in the distal direction, and the distal end side embolus 4 approaches the side path 5. When the pusher 7 is continuously pressed, the rear end of the distal end side embolus 4 passes through the side path 5. At this time, the distal end-side embolus 4 is disposed on the side path 5, and the distal end side of the side path 5 maintains communication with the second chamber, and the rear end side of the side path 5 communicates with the first chamber. In this state, when the pressing force applied to the pusher 7 is not transmitted to the distal end embolus 4, but is transmitted from the rear end embolus 3 to the aqueous dispersion of the drug carrier filled in the first chamber. The water dispersion becomes a force to flow into the second chamber via the side path 5, and the water dispersion sequentially flows from the first chamber to the second chamber, and the air in the second chamber flows into the first chamber. When completed, the rear end side embolus 3 and the front end side embolus 4 are joined. At the time of joining, the pressing to the pusher is stopped, and the medicine 2 in the first chamber is dissolved in the aqueous dispersion 1 of the drug carrier, taking care not to foam. When the cap 6 is loosened without being removed, the cap 6 can be tightened again and mixed by inversion. After a predetermined time necessary for the drug to be captured by the drug carrier, the pusher 7 is pressed again to perform the administration operation.

  In use, the kit preparation of the present invention includes a step of dissolving the dry preparation with an aqueous dispersion of a drug carrier. Since many drug carriers are formed from a solubilizing agent, the aqueous dispersion has an effect as a solubilizing agent. The form of the present invention is suitable when dissolving a hardly soluble dry preparation. This is because the aqueous dispersion of the drug carrier can increase the solubility of the hardly soluble dry preparation that is difficult to dissolve in water for injection, and can achieve a higher concentration than when dissolved in water for injection.

The aqueous dispersion of the drug carrier filled in the first chamber in the present invention will be described in detail. The drug carrier in the present invention is not particularly limited as long as it is stably stored in the state of an aqueous dispersion and a stable aqueous dispersion of the drug carrier can be obtained. Among the carriers, the most common examples include particulate carriers. Examples of the particulate carrier include a W (water phase) / O (oil phase) type and a W / O / W type. Typical W / O type carriers include, for example, micelles, microspheres and the like. Moreover, as a typical W / O / W type | mold carrier, a closed endoplasmic reticulum is mentioned, for example. Among these, closed endoplasmic reticulum is preferable.
A closed endoplasmic reticulum will not be specifically limited if it has a structure which can enclose a chemical | medical agent. Moreover, the closed endoplasmic reticulum used can take various forms. Examples of the closed endoplasmic reticulum include liposomes, microcapsules, lipid microspheres, and nanoparticulates having a potential function capable of encapsulating a drug at a high concentration inside the closed endoplasmic reticulum.

  The carrier can take the form of a sphere or close to it. The particle diameter (diameter of particle outer diameter) is usually 0.01 to 500 μm, preferably 0.03 to 0.4 μm, and more preferably 0.05 to 0.2 μm. Moreover, the particle diameter of a liposome is 0.02-1 micrometer normally, and 0.05-0.2 micrometer is preferable.

The particle size of the microcapsule is usually 1 to 500 μm, preferably 1 to 150 μm. The particle diameter of the lipid microsphere is usually 1 to 500 μm, preferably 1 to 300 μm. The particle diameter of the nanoparticulate is usually 0.01 to 1 μm, preferably 0.01 to 0.2 μm.
In addition, the diameter of particle | grain outer diameter is an average value of the diameter of all the liposome formulation particles measured by a dynamic light scattering method.

Among these, a particularly preferred form is a liposome. Hereinafter, an embodiment in which the carrier used is a liposome will be described as an example.
Liposomes are generally closed endoplasmic reticulum composed of phospholipid bilayer membranes. More specifically, the liposome has a structure in which a phospholipid containing a hydrophobic group and a hydrophilic group forms a membrane based on both polarities, and the membrane forms a space separated from the outside in the interior. is there. The space is an aqueous phase (inner aqueous phase). Liposomes can contain lipids other than phospholipids as membrane constituents. Also, the hydrophilic polymer can be bound to any membrane constituent of the liposome.
The liposome preparation is obtained by using the liposome as a carrier and carrying a drug thereon. In this case, the drug may be present in the inner aqueous phase of the liposome, or may be present in a state immobilized on the surface of the lipid layer, which is a component of the carrier, by electrostatic interaction or the like. It may be in a state where a part or all of the part is included.

  “Phospholipids” are the main constituents of biological membranes and are amphipathic substances that have a group of hydrophobic groups composed of long-chain alkyl groups and hydrophilic groups composed of phosphate groups in the molecule. is there. Examples of phospholipids include phosphatidylcholine (= lecithin). Acid phospholipids include phosphatidylglycerol, phosphatidic acid, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol. Other examples include sphingophospholipids such as sphingomyelin, natural or synthetic phospholipids such as cardiolipin or derivatives thereof, and those obtained by hydrogenating these in accordance with conventional methods. Hereinafter, “phospholipid” may be referred to as phospholipids in the meaning including these. As the main membrane material, a single type of phospholipid may be included, or a plurality of types of phospholipids may be included.

  Liposomes contain phospholipids whose phase transition point is higher than the in-vivo temperature (35 ° C. to 37 ° C.) as a main membrane material in order to prevent the encapsulated drug from easily leaking out during storage or in the living body such as blood. It is preferable to use it. Furthermore, when manufacturing such a liposome, it may be exposed to temperature higher than living body temperature. That is, it may be produced under a temperature condition of about 50 ° C. to 70 ° C., for example, around 60 ° C., and the effect on the liposome formation due to heat becomes large. Therefore, the main membrane material having a phase transition point higher than these temperatures It is particularly preferable to use it. Specifically, the phase transition point of the main membrane material is preferably a phospholipid of 50 ° C. or higher.

The liposome may contain other membrane components together with the main membrane material. For example, it is preferable to include a lipid other than a phospholipid or a derivative thereof (hereinafter sometimes referred to as other lipids), and to form a mixed lipid membrane together with the phospholipid.
The “lipid other than phospholipid” is a lipid having a hydrophobic group composed of a long-chain alkyl group or the like in the molecule and not containing a phosphate group in the molecule. Examples of glycosphingolipids and stabilizers include sterols such as cholesterol described later, and derivatives such as hydrogenated products thereof. Cholesterol derivatives are sterols having a cyclopentanohydrophenanthrene ring, and specific examples thereof include, but are not limited to, cholestanol.
The mixed lipid may contain a single kind of each of other lipids, or may contain a plurality of kinds.

The liposome in the present invention can retain the above-mentioned membrane structure together with the above-described membrane-constituting lipid, and can contain other membrane components that can be contained in the liposome as long as the object of the present invention is not impaired. Examples of the other membrane component include a surface modifier for changing the physical properties of the lipid and imparting desired characteristics to the membrane component of the carrier. Examples of the surface modifier include, but are not limited to, charged substances, derivatives of hydrophilic polymers, and derivatives of water-soluble polysaccharides.
The charged substance in the liposome of the present invention preferably has a charge opposite to that of the drug.

The charged substance is not particularly limited, and examples thereof include a compound having a basic functional group such as an amino group, an amidino group, and a guanidino group, and a compound having an acidic functional group.
Examples of basic compounds include DOTMA disclosed in JP-A No. 61-161246, DOTAP disclosed in JP-A-5-508626, Transfectam disclosed in JP-A-2-292246, TMAG disclosed in Kaihei 4-108391, 3,5-dipentadecyloxybenzamidine hydrochloride, DOSPA, TfxTM-50, DDAB, DC-CHOL, DMRIE, etc. disclosed in WO 97/42166 Can be mentioned.
Examples of the compound having an acidic functional group include fatty acids such as oleic acid and stearic acid, gangliosides having sialic acid such as ganglioside GM1 and ganglioside GM3, and acidic amino acid surfactants such as N-acyl-L-glutamine. It is done.

  When the charged substance is a substance in which a compound having a basic functional group is bound to a lipid, it is called a cationized lipid. The lipid part of the cationized lipid is stabilized in the lipid bilayer of the liposome, and the basic functional group part is present on the membrane surface (outer membrane surface and / or inner membrane surface) of the lipid bilayer of the carrier be able to. By modifying the membrane with a cationized lipid, the adhesion between the liposome membrane and the cells can be enhanced.

  The water-soluble polysaccharide is not particularly limited, and examples thereof include water-soluble polysaccharides such as glucuronic acid, sialic acid, dextran, pullulan, amylose, amylopectin, chitosan, mannan, cyclodextrin, pectin, and carrageenan. Examples of water-soluble polysaccharide derivatives include glycolipids.

When the surface modifier contains a water-soluble polysaccharide, examples of the lipid to which the water-soluble polysaccharide binds include a compound having a hydrophobic region (hydrophobic compound). Examples of the hydrophobic compound include phospholipids constituting the mixed lipid mixture described above, other lipids such as sterols, long chain aliphatic alcohols, polyoxypropylene alkyls, glycerin fatty acid esters, and the like. Among them, phospholipid is one of the preferred embodiments.
Such surface modifiers can be used alone or in combination of two or more.

  Examples of the liposome modified with the hydrophilic polymer include those in which the hydrophilic polymer is chemically or physically bonded to the outer surface of the liposome. Of course, in the liposome, a hydrophilic polymer can be bound to the inside of the liposome. Specific liposomes include, for example, liposomes in which a hydrophilic polymer is bound to both the inside and outside of the membrane, and liposomes in which a hydrophilic polymer is bound only to the outside of the membrane. Among these, liposomes in which only the outer side of the lipid bilayer is selectively surface-modified with a hydrophilic polymer are preferable. This is because, in the case of such a liposome, the hydrophilic polymer can secure the stability of the membrane even when the pH of the inner aqueous phase is low, and the liposome has excellent blood retention. Because.

Separately from the above, a liposome containing a membrane-constituting lipid such as a phospholipid having a reactive functional group is produced by a conventional method, and then a one-end activated PEG is added to the liposome outer solution to have a functional group. Liposomes can also be produced by binding to membrane constituent lipids such as phospholipids.
In addition to the above method, the liposome can also be obtained by mixing the above-described constituent components and discharging them at high pressure with a high-pressure discharge type emulsifier. This method is specifically described in “Liposomes in Life Science” (Terada, Yoshimura et al .; Springer Fairlark Tokyo (1992)), which is described in this specification with reference to this description. To do.

Liposomes modified with hydrophilic polymers are also preferable from the viewpoint of physical stability of the liposomes. This is because modification of the hydrophilic polymer inhibits aggregation and fusion associated with physical contact between the liposomes and enhances the stability of the liposome during long-term storage of the liposome.
The hydrophilic polymer is not particularly limited, but polyethylene glycol, Ficoll, polyvinyl alcohol, styrene-maleic anhydride alternating copolymer, divinyl ether-maleic anhydride alternating copolymer, polyvinyl pyrrolidone, polyvinyl methyl ether, polyvinyl methyl oxazoline. , Polyethyloxazoline, polyhydroxypropyloxazoline, polyhydroxypropylmethacrylamide, polymethacrylamide, polydimethylacrylamide, polyhydroxypropyl methacrylate, polyhydroxyethyl acrylate, hydroxymethylcellulose, hydroxyethylcellulose, polyaspartamide, synthetic polyamino acid, etc. Is mentioned.
Among these, polyethylene glycol (PEG) is preferable because it has an effect of improving retention in blood. The molecular weight of PEG is not particularly limited, but is usually 500 to 10,000 daltons, preferably 1,000 to 7,000 daltons, more preferably 2,000 to 5,000 daltons.

The hydrophilic polymer as described above is usually introduced as a lipid derivative containing a lipid portion (hydrophobic portion). The lipid portion is not particularly limited, and examples thereof include phospholipids, long-chain aliphatic alcohols, sterols, polyoxypropylene alkyls, and glycerin fatty acid esters. For example, when the hydrophilic polymer is polyethylene glycol (PEG), a phospholipid derivative or cholesterol derivative of PEG can be used as the lipid derivative. When the lipid moiety is a phospholipid, it is desirable that the moiety is phosphatidylethanolamine. When the lipid portion is a phospholipid, the acyl chain of the phospholipid is preferably a saturated fatty acid, and the chain length of the acyl chain is C ₁₄ -C ₂₀ , and further C ₁₆ -C _18. Is desirable. Specifically, dipalmitoyl, distearoyl or palmitoyl stearoyl.
Among these, polyethylene glycol-phosphatidylethanolamine (PEG-PE), which is a phospholipid derivative of PEG, is a general-purpose compound and is easily available.

The lipid derivative of the hydrophilic polymer comprises the above hydrophilic polymer and the above lipid. The combination of the hydrophilic polymer and the lipid is not particularly limited. What was combined suitably according to the objective can be used. For example, at least one selected from phospholipids, other lipids such as sterols, long-chain fatty alcohols, and glycerin fatty acid esters, and at least one selected from PEG, PG, and PPG are bonded with high hydrophilicity. And molecular derivatives. Specific examples include polyoxypropylene alkyl. When the hydrophilic polymer is polyethylene glycol (PEG), it is one of preferred embodiments to select phospholipid and cholesterol as the lipid. Examples of the PEG lipid derivative by such a combination include PEG phospholipid derivatives and PEG cholesterol derivatives.
Among these, phospholipid derivatives of PEG are mentioned as one of preferable embodiments. Examples of the phospholipid derivative of PEG include polyethylene glycol-distearoylphosphatidylethanolamine (PEG-DSPE). PEG-DSPE is preferred because it is a general-purpose compound and is easily available.
Said 1st hydrophilic polymer can be used individually or in combination of 2 types or more, respectively.

Such a lipid derivative of a hydrophilic polymer can be produced by a conventionally known method. As a method for synthesizing a phospholipid derivative of PEG, which is an example of a lipid derivative of a hydrophilic polymer, for example, a method in which a phospholipid having a functional group capable of reacting with PEG is reacted with PEG using a catalyst Is mentioned. Examples of the catalyst include cyanuric chloride, carbodiimide, acid anhydride, and glutaraldehyde. Through such a reaction, the functional group and PEG can be covalently bonded to obtain a phospholipid derivative of PEG.
Liposomes that are surface-modified with the lipid derivative of the first hydrophilic polymer prevent the adsorption of opsonin protein and the like in plasma to the surface of the liposomes, thereby improving the blood stability of the liposomes. This makes it possible to avoid trapping with RES, and to improve the delivery property of a drug to a target tissue or cell.

  Liposomes can contain other membrane constituents in addition to the above phospholipids and lipid derivatives of hydrophilic polymers. Examples of other membrane constituents include lipids other than phospholipids and derivatives thereof (hereinafter, these may be referred to as “other lipids”). Liposomes are preferably formed as a membrane of a mixed lipid containing other lipids together with the above-described phospholipid and hydrophilic polymer lipid derivative as a main membrane material.

In the liposome modified with the hydrophilic polymer, the modification rate of the lipid membrane (total lipid) with the hydrophilic polymer is usually 0.1 to 20 mol%, preferably 0.1 to the membrane lipid of the liposome. It is -15 mol%, More preferably, it is 0.2-10 mol%.
When the hydrophilic polymer is PEG, in the liposome modified with PEG, the lipid membrane (total lipid) modification rate by PEG is usually 0.1 to 20 mol% with respect to the membrane lipid of the liposome. , Preferably it is 0.1-10 mol%, More preferably, it is 0.2-7.5 mol%.
In the present invention, the total lipid is the total amount of all lipids constituting the membrane of the liposome containing a lipid derivative of a hydrophilic polymer. Examples of the lipid include phospholipids, lipids of hydrophilic polymer lipid derivatives, other lipids, and lipids contained in surface modifiers.

  In the liposome modified with a hydrophilic polymer, the amount of phospholipid as a main constituent is usually 20 to 100 mol%, preferably 40 to 100 mol% in the whole membrane lipid. Moreover, in the liposome modified with the hydrophilic polymer, the amount of lipids other than phospholipid is usually 0 to 80 mol%, preferably 0 to 60 mol% in the whole membrane lipid.

  Although it does not specifically limit as antioxidant, For example, ascorbic acid, uric acid, a tocopherol analog (for example, vitamin E) is mentioned. Tocopherol has four isomers, α, β, γ, and δ, and any of them can be used in the present invention. The stabilizer and / or antioxidant used is appropriately selected from the above depending on the dosage form, but is not limited thereto. Such stabilizers and antioxidants can be used alone or in combination of two or more. In addition, from the viewpoint of preventing oxidation, the dispersion is preferably packed with an inert gas such as nitrogen.

For sizing liposomes to a desired size, some techniques are available (G.Gregoriadis ed., "Liposome Technology Liposome Preparation and Related Techniques" ^{2 nd edition, Vol.I-III,} CRC Press). It is assumed that the present description is described with reference to this description.
The liposome dispersion can be made into a unilamella by forcibly passing the filter a plurality of times using an extruder. Usually, two or more types of filters having a pore diameter larger than the desired diameter and finally having a desired diameter but having different pore diameters are used.

  Regarding the lipid bilayer structure of liposomes, membrane structures such as Unilamellar vesicles (SUV, Large Unilamellar Vesicle, LUV) and multilamellar vesicles (MLV) composed of multiple sheets are known. . In the present invention, any membrane structure can be used for the liposome. Among them, unilamellar vesicle liposomes are preferred, and LUV liposomes are preferred from the viewpoint of liposome stability.

  Unilamellar vesicle liposomes can be prepared according to conventionally known methods. For example, liposomes are dispersed in a solvent such as absolute ethanol to form a liposome dispersion composed of liposomes mainly composed of multilamellar liposomes having a multi-layer structure. Next, the liposome dispersion is used with an extruder. , Unilamellarized liposomes can be obtained by forcibly passing through the filter a plurality of times. Usually, two or more types of filters having a pore diameter larger than the desired diameter and finally having a desired diameter but having different pore diameters are used. In this way, as the number of passages through filters having different pore sizes is increased using an extruder, the unilamellarization rate increases, and the liposome can be regarded as a substantially unilamellar vesicle liposome. Substantially unilamellar vesicles, specifically, the proportion of unilamellar vesicles in the total carrier (vesicles) constituting the liposome preparation may be 50% or more of the total, 80% The above is preferable.

  The water used in the aqueous dispersion of the drug carrier such as the liposome dispersion prepared in the present invention may further contain a pharmaceutically acceptable additive. Examples of such additives include sodium chloride added for the purpose of adjusting osmotic pressure to form physiological saline, pharmaceutically acceptable organic solvents, collagen, polyvinyl alcohol, polyvinylpyrrolidone, carboxyvinyl. Polymer, sodium carboxymethylcellulose, sodium polyacrylate, sodium alginate, water-soluble dextran, sodium carboxymethyl starch, pectin, methylcellulose, ethylcellulose, xanthan gum, gum arabic, casein, gelatin, agar, diglycerin, propylene glycol, polyethylene glycol, petroleum jelly , Paraffin, stearyl alcohol, stearic acid, human serum albumin (HSA), mannitol, sorbitol, lactose, sucrose, glucose PBS, a biodegradable polymer, a serum-free medium, such as a buffer at physiological pH acceptable in the surfactant or a biological acceptable as pharmaceutical additives. The additive to be used is selected appropriately or in combination from the above depending on the dosage form, but is not limited thereto.

  Among these, from the viewpoint of physical stability during liposome storage, it is desirable to use saccharides and polyhydric alcohols as additives without using electrolytes such as physiological saline. If the electrolyte is present, free water is taken from the surface of the liposome, causing aggregation and fusion between the liposomes, thereby impairing the physical stability of the liposome.

  Among these, it is desirable to adjust the pH from the viewpoint of chemical stability of lipids. It is desirable to set the pH around 6.5 because of the chemical stability of lipids. Furthermore, it is better to stabilize the pH using a buffering agent. Although the buffering agent itself is an electrolyte, the physical stability of the liposome is not impaired if the buffering agent has a concentration of about 20 mM.

  In the kit preparation of the present invention, an aqueous dispersion of a drug carrier in an embodiment containing these additives can be provided as a pharmaceutical composition. The pharmaceutical composition of the present invention can be stored in a usual manner, for example, refrigeration at 0 to 8 ° C. or room temperature of 1 to 30 ° C.

The solid state drug filled in the second chamber in the present invention will be described in detail. The kit preparation of the present invention is not particularly limited, but the solid drug contained in the second chamber is preferably a dry preparation. The form includes solid form, powder form, cake form and the like. The dry preparation of the present invention can be dried by a known method. Examples of the production method include spray drying, freezing and then drying under reduced pressure to obtain a freeze-dried preparation. In the present invention, a lyophilized preparation is desirable in view of rapid solubilization with an aqueous dispersion of a drug carrier.
In the lyophilized preparation, the drug solution may be lyophilized in the second chamber by a known method, or a separate lyophilized preparation may be produced and filled.

  Drugs include drugs for treatment and / or diagnosis. Specifically, for example, nucleic acids, polynucleotides, genes and analogs thereof, anticancer agents, antibiotics, enzyme agents, antioxidant agents, lipid uptake inhibitors, hormone agents, anti-inflammatory agents, steroid agents, vasodilators, angiotensin Converting enzyme inhibitor, Angiotensin receptor antagonist, Smooth muscle cell proliferation / migration inhibitor, Platelet aggregation inhibitor, Anticoagulant, Chemical mediator release inhibitor, Vascular endothelial cell proliferation promoter or inhibitor, Aldose reduction Enzyme inhibitors, mesangial cell growth inhibitors, lipoxygenase inhibitors, immunosuppressants, immunostimulators, antiviral agents, Maillard reaction inhibitors, amyloidosis inhibitors, nitric oxide synthesis inhibitors, AGEs (Advanced glycation endproducts) inhibitors , Drugs used for photochemotherapy, drugs used for neutron capture therapy, used for sonochemical therapy The agents, agents used in hyperthermia, radical scavengers, proteins, peptides, glycosaminoglycans and derivatives thereof, oligosaccharides and polysaccharides and derivatives thereof.

  Among them, dopamine hydrochloride, gabexate mesylate, norepinephrine, bromhexine hydrochloride, metoclopramide, epinephrine, vitamin B1, vitamin B6, carboplatin, cisplatin, oxaliplatin, doxorubicin hydrochloride, epirubicin hydrochloride, gemcitabine hydrochloride, irinotecan hydrochloride, topotenobin sulfate sulfate, tartaric acid Vincristine is preferred.

  The drug is not particularly limited as long as it does not impair the formation of the drug carrier when mixed with the drug carrier. Specific examples include in-vivo diagnostic agents such as X-ray contrast agents, ultrasonic diagnostic agents, radioisotope-labeled nuclear medicine diagnostic agents, and diagnostic agents for nuclear magnetic resonance diagnosis.

  The preparation of the present invention can also be achieved by a method called remote loading in which a drug is introduced by using an ion gradient inside and outside the membrane after forming a carrier liposome. The remote loading method can be used for conventional drugs that can exist in a charged state when dissolved in a suitable aqueous medium. By forming an ion gradient on the inside / outside of the liposome, the drug can permeate the liposome membrane according to the formed gradient and can quickly and efficiently encapsulate the drug in a high concentration. The present invention which is an ergonomic mixed kit preparation can be further improved.

As a gradient formed across the liposome membrane, there is a Na ⁺ / K ⁺ concentration gradient. A technique for adding a drug into a liposome that has been formed in advance by the remote loading method for Na ⁺ / K ⁺ concentration gradient is described in US Pat. No. 5,077,056, and can be carried out with reference to this. It should be noted that this description can be cited as described in this specification.

  A technique for adding a drug in a liposome formed in advance by a remote loading method against an ammonium ion concentration gradient is described in US Pat. No. 5,192,549, and can be performed with reference to this. It should be noted that this description can be cited as described in this specification. Specifically, liposomes are formed in advance in an aqueous buffer containing 0.1 to 0.3 M ammonium salt (for example, ammonium sulfate), and the external medium is a medium that does not contain ammonium ions, such as a sucrose solution. By exchanging, an ammonium ion gradient is formed. Internal ammonium ions are equilibrated by ammonia and protons, and ammonia disappears from the inside of the liposome by diffusing through the lipid membrane. As the ammonia disappears, the equilibrium in the liposome moves continuously in the direction of proton production. By adding a drug to the liposome dispersion having this ion gradient, the drug is quickly enclosed in the liposome.

It is desirable that the liposome preparation carrying the drug obtained in the present invention is efficiently encapsulated in a high concentration in the above carrier. In general, as a method for efficiently encapsulating a drug in a liposome at a high concentration, a method of electrostatically binding to the surface of the liposome, a method of containing the drug in the liposome membrane, and the above-described remote loading method are known. Although any method can be used for the preparation of the present invention, it is necessary to optimize the liposome formulation according to each method.
For example, in the case of a method of electrostatically binding to the liposome surface, the charged substance contained in the liposome membrane needs to have a charge opposite to that of the drug. In general, since drugs are often positively charged, it is common to select a negatively charged acidic phospholipid as the charged substance contained in the liposome membrane. Glycerol is preferred. In this case, it is desirable to keep electrolytes such as NaCl in the liposome dispersion low.
In the case of a method in which a drug is contained in the liposome membrane, it is desirable to lower the phase transition temperature of the liposome membrane. For example, when preparations are made under conditions of 25 ° C., the phase transition temperature is desirably 25 ° C. or lower. In general, it is desirable to use an unsaturated phospholipid having a low phase transition temperature, or a (C ₁₂ -C ₁₆ ) saturated phospholipid having a short alkyl chain. However, when an unsaturated phospholipid is used, it is important to add an antioxidant.
Among the above-described production methods, a method of electrostatically binding to a versatile liposome surface with less restrictions during business mixing is desirable.

  In the present invention, “encapsulation” means a state in which a drug is encapsulated in a carrier. Further, the lipid layer which is a constituent component of the carrier may be in a state where a part or all of the part is included. A drug concentration gradient can occur between the inside of the carrier and the outside of the carrier through the lipid bilayer. Preferably, the carrier of the present invention does not have a drug that has not been encapsulated outside the lipid bilayer after preparation. Then, the medicine enclosed in the carrier is released from the inside to the outside environment. The carrier of the present invention reaches the target site in a state where the drug is encapsulated, and as a result, delivers the encapsulated drug to the target site. The delivery of the drug to the target site may be that the drug supported on the carrier is taken into the target site, or the drug is affected by the target site or its vicinity without being taken into the target site. There may be.

  In the present invention, “release” means that the drug encapsulated in the carrier is released to the outside of the closed vesicle by passing through the lipid membrane constituting the carrier or by changing the structure of a part of the lipid membrane. It means to come.

  In the present invention, the “target site” is a specific site where a drug contained in a carrier is released and acts, and means a cell, tissue, organ or organ specified for each site and the inside thereof. Target sites such as cells, tissues, organs or organs and their interior can be sites to be treated with drugs, and the effect is exerted upon exposure of the released drug. Although it does not specifically limit as a target site, A tumor is mentioned.

  The tumor to be treated is not particularly limited but is a solid tumor, specifically esophageal cancer, stomach cancer, colon cancer, colon cancer, rectal cancer, pancreatic cancer, liver cancer, laryngeal cancer, lung cancer, prostate cancer, Examples include bladder cancer, breast cancer, uterine cancer, or ovarian cancer. Target sites include tumor cells, tissues, organs or organs and their interiors. Therefore, in the present invention, the disease means the above-mentioned tumor, and the drug is expected to show an antitumor effect against them.

  In the present invention, “retention in blood” means the property that a drug encapsulated in a carrier is present in the blood in the host to which the carrier has been administered. When the drug is released from the carrier, it quickly disappears from the blood and acts on the exposed site of the drug. When the retention in blood is good, a smaller amount of drug can be administered.

  In the present invention, “exposure” means that a drug released to the outside of the carrier has an effect on the external environment. Specifically, the released drug exhibits an antitumor effect, which is its action, by approaching and contacting the target site. When the drug acts on the target site, it acts locally on the cells in the cell cycle where DNA synthesis of the target site is performed, and shows the expected effect. In order to exhibit such an effect, it is necessary to maintain a balance between the release rate of the drug from the carrier and the blood retention of the carrier.

The carrier of the present invention can be administered parenterally systemically or locally to a host (patient) in order to expose an effective amount of the drug to the target site at a high concentration for a long time. Examples of the host to be administered include mammals, preferably humans, monkeys, mice, livestock and the like.
As a parenteral administration route, for example, intravenous injection (intravenous injection) such as infusion, intramuscular injection, intraperitoneal injection, and subcutaneous injection can be selected, and an appropriate administration method is selected depending on the age and symptoms of the patient. be able to. The carrier of the invention is administered to a patient already suffering from a disease in an amount sufficient to cure or at least partially block the symptoms of the disease. For example, the effective dose of the drug enclosed in the carrier is selected in the range of 0.01 mg to 100 mg per kg body weight per day. However, the carrier of the present invention is not limited to these dosages. The administration time may be administered after the disease has occurred, or may be administered prophylactically to relieve symptoms at the time of onset when the onset of the disease is predicted. The administration period can be appropriately selected depending on the age and symptoms of the patient.
As a specific administration method, the pharmaceutical composition can be administered by syringe or infusion. In addition, the catheter is inserted into the body of a patient or host, for example, into a lumen, for example, into a blood vessel, and the distal end thereof is guided to the vicinity of the target site. It is also possible to administer from the site where is expected.

EXAMPLES Next, although an Example is given and this invention is demonstrated in more detail, this invention is not limited to these Examples and a test example.
Example 1
The abbreviations and molecular weights of the respective components used are shown below.
HSPC: hydrogenated soybean phosphatidylcholine (molecular weight 790, Lipoid SPC3)
DSPG: Phosphatidylglycerol (molecular weight 801, manufactured by AVANTI POLAR LIPIDS)
Chol: Cholesterol (molecular weight 386.65, manufactured by Solvay)
PEG ₅₀₀₀ -PE: polyethylene glycol (molecular weight 5000) -phosphatidylethanolamine (molecular weight 5938, manufactured by Genzyme)
・ Doxorubicin hydrochloride (manufactured by BORYUNG, molecular weight 579.99)

(1) Preparation of liposome dispersion Anhydrous ethanol in which 0.527 g of hydrogenated soybean phosphatidylcholine (HSPC), 0.258 g of cholesterol (Chol) and 0.321 g of phosphatidylglycerol (DSPG) were heated at 60 ° C. (Dissolved in Wako Pure Chemical Industries, 1 mL) After adding 9 mL of 10% sucrose (10 mM histidine (pH 6.5)) solution, swelled sufficiently, stirred with a vortex mixer, and at 68 ° C., an extruder (The Extruder T). 100, manufactured by Lipex biomembranes Inc., was sequentially passed through a filter (pore size 0.2 μm × 5 times, 0.1 μm × 10 times, manufactured by Whatman) to prepare a liposome dispersion. PEG _5000- PE was introduced into the prepared liposome dispersion to modify PEG on the outer surface of the liposome, followed by purification with a gel column substituted with 10% sucrose (10 mM histidine (pH 6.5)) solution. . The sample after gel filtration was ice-cooled.
(2) Preparation of doxorubicin hydrochloride solution
0.05 g of doxorubicin hydrochloride was dissolved in 10 mL of 5% sucrose solution to obtain a doxorubicin hydrochloride solution.

(3) Production of kit preparation in the form of a two-chamber prefilled syringe The two-chamber prefilled syringe 10 shown in FIG. 1 was used as a container. First, the outer cylinder 8 is prepared, the front end opening of the outer cylinder 8 is sealed with the cap 6, the front end side of the outer cylinder 8 is turned down, and the doxorubicin hydrochloride solution prepared in (2) is prepared from the rear end opening. Was lyophilized according to a conventional method, and a lyophilizing agent was disposed in the space on the distal end side in the outer cylinder. Next, the distal end side embolus 4 is loaded from the rear end opening of the outer cylinder 8, and the distal end side embolus 4 is placed in the outer cylinder at the rear end side of the outer cylinder slightly at the rear end of the side passage 5 to store the lyophilizing agent. The first chamber was formed. Subsequently, the liposome dispersion liquid prepared in (1) and the back end side embolus 3 were charged from the rear end opening of the outer cylinder 8 so as not to form a space portion, thereby forming a second chamber. Thereafter, a pusher 7 was attached to a pusher attachment portion (not shown) at the rear end of the rear end side embolus 3 to produce a kit preparation in the form of a two-chamber prefilled syringe.

(4) Mixing operation of two-chambered prefilled syringe-type kit preparation For the kit preparation of the two-chambered prefilled syringe 10 form manufactured in (3), loosen the cap 6 with the cap 6 and leave it in a semi-empty state while maintaining the wearing state. By slowly pushing the pusher 7, the aqueous dispersion (liposome dispersion) 1 of the drug carrier in the first chamber is fed into the second chamber via the side path 5. After confirming that the aqueous dispersion 1 of the drug carrier was completely fed into the second chamber, the cap 6 was tightly sealed again, and doxorubicin hydrochloride was dissolved by inversion mixing.

(5) Confirmation of state of mixed doxorubicin hydrochloride-drug carrier dispersion liquid The mixed doxorubicin hydrochloride-drug carrier dispersion liquid is taken out by mixing operation of (4), and physiological saline is added thereto. After 20-fold dilution, ultracentrifugation (1 × 10 ⁵ g, 2 hours, 10 ° C.) was performed to precipitate doxorubicin hydrochloride-drug carrier. The doxorubicin hydrochloride-drug carrier dispersion diluted with physiological saline before ultracentrifugation was further diluted 2-fold, and the total amount of doxorubicin hydrochloride was determined by fluorescence measurement (excitation wavelength: 480 nm, fluorescence wavelength: 580 nm). In addition, by quantifying doxorubicin hydrochloride present in the supernatant after ultracentrifugation, (doxorubicin hydrochloride in the supernatant) / (doxorubicin hydrochloride in the total amount) X100 was determined, and doxorubicin hydrochloride-drug carrier could not be formed. The abundance (%) of free doxorubicin hydrochloride was calculated. As a result, the abundance (%) of free doxorubicin hydrochloride was 6.3%.

FIG. 1 is a cross-sectional view of a two-chamber type prefilled syringe according to an embodiment of the present invention. 2 is a cross-sectional view taken along the line aa of the two-chamber type prefilled syringe shown in FIG.

Claims (6)

A drug carrier carrying a drug is prepared by having an aqueous dispersion of a drug carrier that is stably stored and a solid drug that is stably stored and mixing the aqueous dispersion and the drug. DDS preparation characterized by being made. The aqueous dispersion of the drug carrier is filled in the first chamber of the container, and the drug is filled in the second chamber of the container, and the first chamber and the second chamber are isolated by an isolation means capable of communicating with each other. The DDS preparation according to claim 1, which has the container. The DDS preparation according to claim 2, wherein the container is a two-chamber type prefilled syringe. The DDS preparation according to any one of claims 1 to 3, wherein the drug carrier is a liposome. The DDS preparation according to claim 4, wherein the liposome is charged and adsorbs a drug on the surface thereof by electrostatic interaction during ergonomic mixing. 6. The DDS preparation according to claim 4 or 5, wherein the liposome has a pH gradient between its inner and outer aqueous phases, whereby the drug can be efficiently retained in the inner aqueous phase during ergonomic mixing.

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