WO2003022264A1

WO2003022264A1 - Paclitaxel mixed composition and water-in-oil type emulsion formulation for chemoembolization and preparation method thereof

Info

Publication number: WO2003022264A1
Application number: PCT/KR2001/001613
Authority: WO
Inventors: Hesson Chung; Seo Young Jeong; Ick Chan Kwon; Jae Hyung Park; Jin Wook Chung; Young Man Kim; In-Hyun Lee
Original assignee: Korea Institute Of Science And Technology; Daehwa Pharm. Co., Ltd.
Priority date: 2001-09-13
Filing date: 2001-09-26
Publication date: 2003-03-20
Also published as: CN100544713C; KR20030023470A; KR100539451B1; JP2005503398A; CN1547469A

Abstract

The present invention relates to the paclitaxel mixed composition and water-in-oil type emulsion formulation for chemoembolization and preparation method thereof. The combinatory formulation of anticancer drugs can be easily prepared since the emulsion formulation of the present invention can include other hydrophilic or lipophilic drugs.

Description

PACLITAXEL MIXED COMPOSITION AND WATER-IN-OIL TYPE EMULSION FORMULATION FOR CHEMOEMBOLIZATION AND PREPARATION METHOD

THEREOF

TECHNICAL FIELD

The present invention relates to oily paclitaxel composition and formulation for transcatheter arterial chemoembolization (TACE) by solubilizing paclitaxel and the preparation method thereof.

TACE is a cancer treatment method that prevents the nutrition supplies to the cancer tissue by injecting embolizing materials and anticancer agents though the feeding artery of tumor while visualizing the operation process with contrast medium.

BACKGROUND ART

The most widely used TACE is transcatheter arterial chemoembolization through hepatic artery for the treatment of hepatoma. The contrast medium serves as a visualization tool during and after the operation and also causes embolism in the tumor. The anticancer drugs such as doxorubicin (adriamycin), cisplatin and carboplatin are dissolved or suspended in oily contrast medium.

One of the most frequently used contrast media in TACE is an iodized oil such as Lipiodol®. The suspension system comprising Lipiodol and above- mentioned anticancer drugs, however, is physically unstable and therefore has many limitations during the operation. The anticancer agents such as doxorubicin and epirubicin are used conventionally for the treatment of hepatoma in Radiology. Most of the anticancer agents, however, are water-soluble materials. Therefore, suspension type formulation, rather than oily solution, was used in TACE (Yoshihiro Katagiri et al., Cancer Chemother. Pharmacol 1989, 23, 238-242). The suspension type formulation, however, cannot be stored for a prolonged period of time since particles aggregate with time. To overcome this stability problem, anticancer drug is dissolved in the aqueous contrast medium before dispersing the aqueous phase in the oily contrast medium such as Lipiodol®. In other words, anticancer drug is dissolved in the aqueous contrast medium and mixed with oily contrast medium by pumping method just before administering to a patient.

To maximize the stability of the emulsion, aqueous contrast mediums such as Urografin (specific gravityl .328-1.332) or lopamiro (specific gravity 1.17- 1.41) are used since they have similar specific gravities with Lipiodol (1.275- 1.290)(Takashi Kanematsu et al., Journal of surgical oncology 1984, 25, 218-226, Takafumi lchida et al., Cancer Chemother. Pharmacol 1994, 33, 74-78). However, only a transient emulsion that phase-separates in a few minutes after preparation is produced by the above method. The unstable emulsion system does not provide enough embolizing effect. In reality, phase separation can be observed inside the catheter during the operation. When this unstable emulsion is administered, adriamycin is absorbed immediately to the tissue and therefore does not provide an effect of sustained delivery of anticancer drug.

One of the ideal hepatoma treatment uses a synthetic polymeric anticancer agent, poly(styrene-co-maleic acid)-conjugated neocarzinostatin (SMANCS). SMANCS can be solubilized in Lipiodol since it has both hydrophilic and hydrophobic properties (Konno, T. and Maeda, H., Targeting chemotherapy of hepatocellular carcinoma. Neoplasms of the liver, Eds. Okuda, K., and Ishak, K. G., Springger-Verlag, Berlin, P343-352). Even though SMANCS/Lipiodol formulation has solved the stability problems of adriamycin/Lipiodol formulation, SMANCS/Lipiodol formulation is not widely used due to the high price and severe toxic side effects.

On the other hand, paclitaxel, an anticancer agent, shows excellent cytotoxicity to ovarian cancer, breast cancer, esophagus cancer, melanoma and leukemia. Paclitaxel has been commerciallized as intravenous injection Taxol® by Bristol-Myers Squibb Company.

Paclitaxel is a one of the water-insoluble drug and therefore the solubilization technique has been developed along with the drug itself. One of the examples in the solubilization technique is the use of solubilizing agent for systemic administration such as intravenous injection. The above-mentioned Taxol® uses Cremophor EL (polyoxyethylene 35 castor oil) and ethanol as solubilizing agents. Taxol® is a pre-concentrate type formulation that forms spontaneously microemulsion when dispersed in excess amount of water (US patent 5438072). It is known, however, that solubilizing agent in Taxol® causes toxic side effects. Therefore, many studies are performed to develop new paclitaxel formulations with high anticancer activity and low toxic effects.

Even though the most typical TACE is TACE through hepatic artery, it can be applied to a variety of solid tumors. For instance, SMANCS/Lipiodol formulation has been used for the targeted therapy of renal cancer by performing TACE through renal artery (K. Tsuchiya, Tumor-targeted chemotherapy with SMANCS in Lipiodol for renal cell carcinoma: longer survival with larger size tumors. Urology. 2000 Apr;55(4):495-500).

SUMMARY OF THE INVENTION

Paclitaxel has never been used as an anticancer drug for embolization or angiography. The object of the present invention is to use paclitaxel in transcatheter arterial chemoembolization by emulsifying it with oily contrast medium and aqueous contrast medium. The biggest problem of the conventional adriamycin/Lipiodol/lopamiro emulsion is low stability. Phase separation occurs several minutes after emulsification by the pumping method and is often observed in the catheter. Sustained delivery of anticancer drug cannot be expected with the conventional formulation.

Therefore, there is a need for a new type of formulation for chemoembolization that can maintain the emulsion stability during and even after

TACE unlike the conventional adriamycin/Lipiodol/lopamiro formulation and that can be produced at a lower cost and has lower toxic side effects than conventional SMANCS/Lipiodol formulation.

Therefore, one of the objects of the present invention is to provide a new composition of paclitaxel that can solubilize paclitaxel.

More particularly, the object of the present invention is to provide an emulsion formulation of paclitaxel that can be used for the treatment of solid tumors by transcatheter arterial chemoembolization. Another object of the present invention is to provide a preparation method of paclitaxel mixed composition and the water-in-oil (w/o) type emulsion.

DETAILED DESCRIPTION OF THE INVENTION

While trying to achieve the above objects, the present inventors have found unexpectedly that w/o type emulsion of oily contrast medium/aqueous contrast medium/paclitaxel is remarkably more stable than Lipiodol/lopamiro/doxorubicin emulsion conventionally used in TACE. In other words, the present invention is completed by finding out that the emulsion system becomes very stable physically and paclitaxel is effectively solubilized when paclitaxel is used in the place of doxorubicin. Also the stability of the conventional Lipiodol/lopamiro/doxorubicin emulsion increases dramatically by merely adding paclitaxel.

More particularly, the present invention provides a mixed composition comprising 50 ~ 98.9 % (v/v) of oily contrast medium solubilizing 0.01 ~ 1 % (w/v) of paclitaxel and 0.1 - 50 % (v/v) of aqueous contrast medium.

The present invention also provides a stable water-in-oil type emulsion prepared by homogeneously mixing oily contrast medium phase and aqueous contrast medium phase with a physical force to the above mixed composition solubilizing.

As mentioned above, the Lipiodol/lopamiro/doxorubicin formulation is prepared by pumping more than 100 times, but is a very unstable emulsion system that phase-separates within several minutes after preparation. In distinct contrast, the w/o emulsion of paclitaxel/oily contrast medium/aqueous contrast medium according to the present invention does not show phase separation for more than one month. Therefore, it can be concluded that paclitaxel itself has an important role in increasing the stability of the oily contrast medium/aqueous contrast medium. Therefore the emulsion can be stably formed many hours before TACE by physically mixing the mixed composition of the present invention. The aqueous phase and oily phase are thoroughly and stably mixed once the emulsion is prepared. Therefore the mixed composition of the present invention eliminates the stability problems of the conventional emulsion.

The oily contrast medium/aqueous contrast medium/paclitaxel emulsion exhibits very improved physically properties when compared to the Lipiodol formulations containing water-soluble anticancer agents such as doxorubicin. The mixed composition of the present invention has a similar characteristics to SMANCS/Lipiodol formulation. In contrast to the SMANCS/Lipiodol formulation that has to the high price and toxic side effects, the mixed composition uses relatively inexpensive raw materials and very easy to prepare that can lower the production cost.

An example of an oily contrast medium that can be used in preparing the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition and emulsion of the present invention is an iodized oil. The iodized oils include iodized poppy seed oil such as Lipiodol (Laboratoire Guerbet, France), Ethiodol (Savage Laboratories, Melville, NY)) and iodized soybean oil). The iodized soybean oil is described by Ma Tai (The effect of oral iodized oil on prevention and treatment of endemic goiter. Chinese Med. J. 61 (9):533, 1981).

The amount of paclitaxel in the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition and emulsion of the present invention is 0.001 ~ 1.5 % (w/v). When the amount of paclitaxel exceeds 1.5 % (w/v), it is not preferable since the excess paclitaxel precipitates. On the other hand, anticancer activity is too low, and emulsion is unstable when the amount of paclitaxel is lower than 0.001 % (w/v).

The iodine content of the iodized oil used as an oily contrast medium in the present invention is preferably 30 ~ 50 % by weight. More preferably, the iodine content is between 35 ~ 45 % by weight. It is the most preferable to use Lipiodol as the oily contrast medium.

The amount of the oily contrast medium in the paclitaxel/oily contrast medium/aqueous contrast medium emulsion of the present invention is 50 ~

98.9 % (v/v), and preferably 75 ~ 80 % (v/v). When the amount of oily contrast medium is less than 50 % (v/v) or more than 98.9 % (v/v), it is not preferable since the emulsion becomes unstable.

The aqueous contrast medium in the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition and emulsion of the present invention can be selected from a group consisting of Metrizamide, Diatrizoate, loxaglate, lopentol, lopamidol, lomeprol, lotrolan, lohexol, loversol, loxilan, lopromide, lodixanol or lobitridol. Among these, iopamidol commercialized as lopamiro is the most preferable.

The amount of aqueous contrast medium is 0.1 ~ 50 % (v/v), and preferably 20 ~ 25 % (v/v). Also, the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition and emulsion of the present invention can additionally include other anticancer drugs than paclitaxel. The anticancer drugs that can be added include doxorubicin (also known as adriamycin), 5-fluorouracil, carboplatin, cisplatin, carmustine, dacabazine, etoposide, Vinorelbine, Topotecan, Irinotecan, and Estramustine. The amount of the additionally included anticancer drugs is 0.0001 - 2 %(w/v) of the total mixed composition.

Also the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition and emulsion of the present invention can additionally include 0.0001 ~ 20 % by weight of emulsifier. Emulsifiers can be solubilized in aqueous contrast medium and include phospholipids, non-ionic surfactants, anionic surfactants, cationic surfactants and bile salts.

The phospholipids that can be used as an emulsifier of the present invention are phosphatidylcholines and their derivatives, phosphatidylethanolamines and their derivatives and phosphatidylserines and their derivatives, or polymeric lipid where the hydrophilic polymers are covalently-bonded to a phospholipid.

The non-ionic surfactants that can be used as an emulsifier of the present invention are poloxamers (also known as pluronic: a copolymer of polyoxyethylene and polyoxypropylene), hydrogenated castor oils (HCO), sorbitan esters (Span) and polyoxyethylene-sorbitan fat acid esters (Tween) or polyoxyehtylene ethers (Brij).

The anionic surfactants that can be used as an emulsifier of the present invention are phosphatidylserines and their derivatives, phosphatidic acids and their derivatives and sodium dodecyl sulfate.

The cationic surfactants that can be used as an emulsifier of the present invention are 1 ,2-dioleoyl-3-trimethylammonium-propane (DOTAP), dimethyldioctadecyl ammonium bromide (DDAB), N-[1-(1 ,2-dioleoyloxy)propyl]-N,N,N-thmethylammonium chloride (DOTMA),

1 ,2-dioleoyl-3-ethylphosphocholine (DOEPC) and 3β-[N-[(N',N'-

dimethylamino)ethan]carbamoyl]cholesterol (DC-Choi).

The bile salts that can be used as an emulsifier of the present invention are cholic acids, their salts and derivatives; deoxycholic acids, their salts and derivatives; chenocholic acids, their salts and derivatives; ursodeoxycholic acids, their salts and derivatives; and lithocholic acids, their salts and derivatives.

The paclitaxel/oily contrast medium/aqueous contrast medium mixed composition of the present invention can be easily prepared by adding 1 ) oily contrast medium solubilizing paclitaxel in above mentioned composition range by stirring and 2) aqueous contrast medium.

To speed up the solubilization process of paclitaxel in the oily contrast

medium, it is acceptable to raise the temperature to 35 ~ 45 °C or to sonicate in a

bath type sonicator. The prepared paclitaxel/oily contrast medium/aqueous contrast medium mixed composition of the present invention is stored after sterilization process. It is acceptable to use sterilized raw materials and to mix them under a sterile environment. Or the paclitaxel/oily contrast medium composition can be sterilized by injecting through a sterile syringe filter (pore size

200 μm, PVDF sterile filter). It is also acceptable to sterilize and to mix the

iodized poppy seed oil and paclitaxel or to sterilize the composition by using gamma ray or EO gas sterilization protocols.

When an additional anticancer agent is included other than paclitaxel, the anticancer agent can be solubilized in the aqueous contrast medium in the above described composition range if the additional anticancer agent is soluble in aqueous environment. If the additional anticancer agent is lipophilic, the anticancer agent can be solubilized in the oily contrast medium in the above described composition range.

The prepared paclitaxel/oily contrast medium/aqueous contrast medium mixed composition of the present invention can be emulsified by vortexing for transcatheter arterial chemoembolization. After vortexing, the emulsion was stable for more than 30 days without showing phase separation at room temperature. The whole process of TACE takes 3 - 5 hours at most. Therefore, the emulsion of the present invention can stay stable during the operation and presumably inside the tumor releasing the anticancer drug in a sustained fashion. This is a remarkable improvement over the conventional doxorubicin/Lipiodol/lopamiro formulation, which phase separates in several minutes after emulsion formulation by pumping.

Therefore, the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition of the present invention can be supplied as a mixture of two phases comprising the oil phase solubilizing paclitaxel and the aqueous phase solubilizing additional anticancer drug. The paclitaxel/oily contrast medium/aqueous contrast medium formulation of the present invention can also be supplied as an w/o emulsion by mixing homogeneously with a physical force to the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition. The emulsion formulation according to the present invention is stable without phase separation for at least 2 months after emulsification.

Also the amount and the method of the administration of the paclitaxel/oily contrast medium/aqueous contrast medium emulsion of the present invention can be varied up to the decision of the doctor depending on the age, sex, weight, and severeness of the patient. Generally, TACE can be performed once in 1 ~ 4 months and can be repeated similar to that with doxorubicin/oily contrast medium/aqueous contrast medium. Two to 15 ml of the formulation is injected through the feeding artery of a solid tumor, for instance through hepatic artery in case of hepatoma.

The invention will be further illustrated by the following examples. It should be understood that these examples are intended to be illustrative only and the present invention is not limited to the conditions, materials or devices recited therein.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is photographs of a composition comprising 0.8 ml of Lipiodol and 0.2 ml of lopamiro (left) and a composition comprising 0.8 ml of Lipiodol, 8 mg of paclitaxel and 0.2 ml of lopamiro (right) taken before vortexing, immediately after vortexing and 3 hours after vortexing.

Figure 2 is photographs of a composition comprising 0.8 ml of Lipiodol, 0.2 ml of lopamiro and 4 mg of doxorubicin (left) and a composition comprising 0.8 ml of Lipiodol, 8 mg of paclitaxel, 0.2 ml of lopamiro and 4 mg of doxorubicin (right) taken before vortexing, immediately after vortexing and 3 hours after vortexing.

Figure 3 is photographs of a composition comprising 0.8 ml of Lipiodol,

0.2 ml of lopamiro and 4 mg of carboplatin (left) and a composition comprising 0.8 ml of Lipiodol, 8 mg of paclitaxel, 0.2 ml of lopamiro and 4 mg of carboplatin (right) taken before vortexing, immediately after vortexing and 3 hours after vortexing.

Figure 4 is photographs of a composition comprising 0.8 ml of Lipiodol, 0.2 ml of lopamiro and 4 mg of cisplatin (left) and a composition comprising 0.8 ml of Lipiodol, 8 mg of paclitaxel, 0.2 ml of lopamiro and 4 mg of cisplatin (right) taken before vortexing, immediately after vortexing and 3 hours after vortexing.

Figure 5 is a graph comparing the particle size of the w/o type emulsions comprising 0.8 ml of Lipiodol, 0.2 ml of lopamiro and various anticancer drugs without paclitaxel (left) and with paclitaxel (right).

Figure 6 is a graph showing the result of in vitro release of doxorubicin from the compositions comprising Lipiodol/lopamiro/doxorubicin (0.8ml/0.2 ml/4 mg) and Lipiodol/lopamiro/doxorubicin/paclitaxel (0.8ml/0.2 ml/4 mg/8 mg). EXAMPLES

Example 1. Preparation of Lipiodol/lopamiro/Paclitaxel emulsion

Eight hundred microliters of Lipiodol (Lipiodol Ultra-fluid, Laboratoire Guerbet, France, Iodine content 38 % by weight) was used as an oily contrast medium. Lipiodol and 8 mg of paclitaxel (Samyang Genex, Korea) were added in test tubes ( micro test tubes with safety lock, polyethylene, 1.5 ml, Eppendorf AG, Germany) and solubilized by stirring at room temperature. To speed up the

solubilization process, the temperature was raised to 40 °C. Two hundred

microliters of lopamiro (Bracco s.p.a. Italy) was added to this oily mixture. A control mixture was made by mixing 0.8 ml of Lipiodol and 0.2 ml of lopamiro. The pictures taken after preparing these two mixtures are shown in Figure 1 (upper panel). The mixtures were vortexed by using a vortex mixer at a maximum setting (120 V, 0.65 A, 60 Hz) for 10 minutes. Immediately after vortexing, the Lipiodol/lopamiro/paclitaxel formulation formed an emulsion without phase separation, but the phase separation was observed in the Lipiodol/lopamiro composition (middle panel). In 3 hours after vortexing, emulsion was stable in the Lipiodol/lopamiro/paclitaxel composition, but the phase separation was almost complete in the Lipiodol/lopamiro composition (lower panel). The prepared Lipiodol/lopamiro/paclitaxel composition shows only small aqueous droplets (100 - 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in and helps increasing the Lipiodol/lopamiro/paclitaxel formulation. Example 2. Preparation of Lipiodol/lopamiro/paclitaxel/doxorubicin emulsion

Eight hundred microliters of Lipiodol (Lipiodol Ultra-fluid, Laboratoire Guerbet, France, Iodine content 38 % by weight) was used as an oily contrast medium. Lipiodol and 8 mg of paclitaxel (Samyang Genex, Korea) were added in test tubes (micro test tubes with safety lock, polyethylene, 1.5 ml, Eppendorf AG, Germany) and solubilized by stirring at room temperature. To speed up the solubilization process, the mixture was sonicated in a bath type sonicator. Two hundred microliters of lopamiro (Bracco s.p.a. Italy) containing 4 mg of doxorubicin (Sigma Chemical Co.) was added to this oily mixture. A control mixture was made by mixing 0.8 ml of Lipiodol and 0.2 ml of lopamiro containing 4 mg of doxorubicin. The pictures taken after preparing these two mixtures are shown in Figure 2 (upper panel). The mixtures were vortexed by using a vortex mixer at a maximum setting (120 V, 0.65 A, 60 Hz) for 10 minutes. Immediately after vortexing, the Lipiodol/lopamiro/paclitaxel/doxorubicin formulation formed an emulsion without phase separation, but the phase separation was observed in the Lipiodol/lopamiro/doxorubicin composition (middle panel). In 3 hours after vortexing, the emulsion was still stable in the

Lipiodol/lopamiro/paclitaxel/doxorubicin composition, but the phase separation was almost complete in the Lipiodol/lopamiro/doxorubicin composition (lower panel). The prepared Lipiodol/lopamiro/paclitaxel/doxorubicin composition shows only small aqueous droplets (200 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in and helps increasing the Lipiodol/lopamiro/paclitaxel/doxorubicin formulation. Example 3. Preparation of Lipiodol/lopamiro/paclitaxel/carboplatin composition

The composition and control group was prepared as in Example 2 except that 4 mg of was used instead of doxorubicin. The pictures taken after preparing these two mixtures are shown in Figure 3 (upper panel). The mixtures were vortexed by using a vortex mixer at a maximum setting (120 V, 0.65 A, 60 Hz) for 10 minutes. Immediately after vortexing, the

Lipiodol/lopamiro/paclitaxel/carboplatin formulation formed an emulsion without phase separation, but the phase separation was observed in the Lipiodol/lopamiro/carboplatin composition (middle panel). In 3 hours after vortexing, the emulsion was still stable in the

Lipiodol/lopamiro/paclitaxel/doxorubicin composition, but the phase separation was almost complete in the Lipiodol/lopamiro/carboplatin composition (lower panel). The prepared Lipiodol/lopamiro/paclitaxel/carboplatin composition shows only small aqueous droplets (400 ~ 600 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in and helps increasing the Lipiodol/lopamiro/paclitaxel/carboplatin formulation.

Example 4. Preparation of Lipiodol/lopamiro/paclitaxel/cisplatin composition

Lipiodol/lopamiro/paclitaxel/cisplatin formulation formed an emulsion without phase separation, but the phase separation was observed in the Lipiodol/lopamiro/cisplatin composition (middle panel). In 3 hours after vortexing, the emulsion was still stable in the

Lipiodol/lopamiro/paclitaxel/doxorubicin composition, but the phase separation was almost complete in the Lipiodol/lopamiro/cisplatin composition (lower panel). The prepared Lipiodol/lopamiro/paclitaxel/cisplatin composition shows only small aqueous droplets (500 ~ 900 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in and helps increasing the Lipiodol/lopamiro/paclitaxel/ cisplatin formulation.

Example 5. Particle size of the Lipiodol/lopamiro emulsion in the presence of paclitaxel

The size of water droplet in the w/o type emulsions prepared in Examples 1 ~ 4 was measured by diluting the emulsions 100 times with soybean oil with Malvern Zetasizer (QELS method). The refractive index and viscosity of the medium were set to those of main ingredient, triolein and are 1.84 (Handbook of Chemistry and Physics, 23th ed, CRC Press) and 69.3 cSt/s (Chung et. al., J. Cont. Rel. (2001) 71 :339-350), respectively. The refractive index and viscosity of the particles were set to 1.84 and 0.97 cSt/s, respectively. The particle size has been measured immediately after and 3 hours after vortexing and is shown in Figure 5. In the formulations without paclitaxel, those with carboplatin and cisplatin are relatively stable immediately after preparation, but the particle size grows to 5 μm, and phase separation occurs 3 hours after vortexing. Since the

particle aggregation was observed in the emulsions made without paclitaxel, they are very unstable. On the other hand, the particle size does not increase 3 hours after vortexing when paclitaxel was added showing that the emulsions are very stable.

Example 6. In vitro release of Doxorubicin from Lipiodol/lopamiro emulsions

Two hundred microliters of Lipiodol/lopamiro/doxorubicin and Lipiodol/lopamiro/paclitaxel/doxorubicin emulsions prepared in Example 2 were put in dialysis bags, and both ends of the bag were sealed with closures. The bags were immersed in 10 ml of phosphate buffered saline. The in vitro release

experiment was performed in a shaking water bath at 37 °C. The concentration

of the released doxorubicin was analyzed by using UV/visible spectrophotometer. The result is shown in Figure 6. The release rate of doxorubicin was slower in the emulsion with paclitaxel than that without paclitaxel. Paclitaxel increases the emulsion stability slows down the release rate of doxorubicin since more than 30 % of doxorubicin still remained in the emulsion even after 140 hours.

Example 7. Preparation of Lipiodol/lomeprol/paclitaxel composition

The composition and control group was prepared as in Example 1 except that 0.2 ml of lomeprol (lomeron 300 injection, llsung Pharmaceutical Company, Korea) was used instead of lopamiro. The prepared Lipiodol/lomeprol/paclitaxel composition shows only small aqueous droplets (100 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in the Lipiodol/lomeprol/paclitaxel formulation.

Example 8. Preparation of Lipiodol/ lopromide/paclitaxel composition

The composition and control group was prepared as in Example 1 except that 0.2 ml of lopromide (Ultravist 370 injection, Korea Shering Company) was used instead of lopamiro. The prepared Lipiodol/lopromide/paclitaxel composition shows only small aqueous droplets (100 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in the Lipiodol/lomeprol/paclitaxel formulation.

Example 9. Preparation of Lipiodol/lodixanol/paclitaxel composition

The composition and control group was prepared as in Example 1 except that 0.2 ml of lopromide (Visipaque 320 mg/ml, Nycomed Ireland Ltd.) was used instead of lopamiro. The prepared Lipiodol/lodixanol/paclitaxel composition shows only small aqueous droplets (100 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in the Lipiodol/lomeprol/paclitaxel formulation.

Example 10. Preparation of Ethiodol/lopamiro/paclitaxel composition

The composition and control group was prepared as in Example 1 except that 0.8 ml of Ethiodol (Savage Laboratories, Melville, NY) was used instead of Lipiodol. The prepared Ethiodol/lopamiro/paclitaxel composition shows only small aqueous droplets (100 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in the Ethiodol/lopamiro/paclitaxel formulation.

Example 11. Preparation of Lipiodol/lopamiro/paclitaxel/HCO 60 composition

The composition and control group was prepared as in Example 1 except that 0.2 ml of lopamiro containing 0.002 mg of HCO 60 was used instead of lopamiro. The prepared Lipiodol/lopamiro/paclitaxel/HCO 60 composition shows only small aqueous droplets (100 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in the Lipiodol/lopamiro/paclitaxel/HCO 60 formulation.

Example 12. Preparation of Lipiodol/lopamiro/paclitaxel/Tween 20 composition

The composition and control group was prepared as in Example 1 except that 0.2 ml of lopamiro containing 10 mg of Tween 20 (Sigma) was used instead of lopamiro. The prepared Lipiodol/lopamiro/paclitaxel/Tween 20 composition shows only small aqueous droplets (100 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in the Lipiodol/lopamiro/paclitaxel/Tween 20 formulation.

Example 13. Preparation of Lipiodol/lopamiro/paclitaxel/egg phosphatidylcholine composition The composition and control group was prepared as in Example 1 except that 0.2 ml of lopamiro containing 10 mg of egg phosphatidylcholine (Sigma) was used instead of lopamiro. The prepared Lipiodol/lopamiro/paclitaxel/egg phosphatidylcholine composition shows only small aqueous droplets (100 ~ 500 nm) under a microscope. Since the paclitaxel precipitation is not visible, it was confirmed that paclitaxel is completely solubilized in the Lipiodol/lopamiro/paclitaxel/egg phosphatidylcholine formulation.

EFFECT OF THE INVENTION

The paclitaxel/oily contrast medium/aqueous contrast medium mixed composition of the present invention is composed of an oil phase solubilizing paclitaxel and an aqueous phase alone or with additionally solubilized anticancer drug. The paclitaxel/oily contrast medium/aqueous contrast medium mixed composition of the present invention can be formulated as a w/o emulsion form by homogeneously mixing the oil and aqueous phase with a physical force such as vortexing. The mixed composition of the present invention can be supplied as a stable w/o emulsion solubilizing paclitaxel and therefore can be administered via different routes other than conventional intravenous route. The paclitaxel/oily contrast medium/aqueous contrast medium mixed composition and emulsion formulation of the present invention according to the present invention has a dramatically improved physical stability when compared to the conventional Lipiodol/lopamiro/doxorubicin formulation. Also, other anticancer drugs can also be solubilized in the paclitaxel/oily contrast medium/aqueous contrast medium mixed composition and emulsion formulation of the present invention. Therefore, paclitaxel/oily contrast medium/aqueous contrast medium formulation of the present invention is a new type of formulation that overcomes the problems associated with the conventional Lipiodol/lopamiro/doxorubicin formulation. At the same time, the present invention provides a new administration route for paclitaxel, namely by transcatheter arterial chemoembolization, which has been mainly used as an injection formulation via intravenous route.

Claims

1. A mixed composition to prepare emulsion for chemoembolization comprising 50 ~ 98.9% (v/v) of oily contrast medium solubilizing 0.01 ~ 1 % (w/v) of paclitaxel and 0.1 - 50 % (v/v) of aqueous contrast medium.

2. A water-in-oil type emulsion composition solubilizing paclitaxel for chemoembolization comprising 50 ~ 98.9% (v/v) of oily contrast medium solubilizing 0.01 ~ 1 % (w/v) of paclitaxel and 0.1 - 50 % (v/v) of aqueous contrast medium.

3. The composition of Claiml or Claim 2 wherein the oily contrast medium is an iodized oil of iodine content ranging 30 ~ 50 % by weight selected from the group consisting iodized poppy seed oil including Lipiodol and Ethiodol and iodized soybean oil.

4. The composition of Claim 3 wherein the iodine content of the oily contrast medium is 35 ~ 48 % by weight.

5. The composition of Claim 1 or Claim 2 wherein the aqueous contrast medium is selected from the group consisting of Metrizamide, Diatrizoate, loxaglate, lopentol, lopamidol, lomeprol, lotrolan, lohexol, loversol, loxilan, lopromide, lodixanol and lobitridol.

6. The composition of Claim 4 wherein the aqueous contrast medium is selected from the group consisting of Metrizamide, Diatrizoate, loxaglate, lopentol, lopamidol, lomeprol, lotrolan, lohexol, loversol, loxilan, lopromide, lodixanol and lobitridol.

7. The composition of Claim 4 wherein the aqueous contrast medium is iopamidol.

8. The composition of Claim 1 or Claim 2 wherein 0.0001 ~ 20 % by weight of emulsifier was additionally included.

9. The composition of Claim 8 wherein the emulsifier is selected from the group consisting of phospholipids, non-ionic surfactants, anionic surfactants, cationic surfactants and bile salts.

10. The composition of Claim 9 wherein the phospholipids are selected from the group consisting of phosphatidylcholines and their derivatives, phosphatidylethanolamines and their derivatives and phosphatidylserines and their derivatives, or polymeric lipid where the hydrophilic polymers are covalently-bonded to a phospholipid.

11. The composition of Claim 9 wherein the non-ionic surfactants are selected from the group consisting of poloxamers (also known as pluronic: a copolymer of polyoxyethylene and polyoxypropylene), hydrogenated castor oils (HCO), sorbitan esters (Span) and polyoxyethylene-sorbitan fat acid esters (Tween) and polyoxyehtylene ethers (Brij).

12. The composition of Claim 9 wherein the anionic surfactants are selected from the group consisting of phosphatidylserines and their derivatives, phosphatidic acids and their derivatives and sodium dodecyl sulfate.

13. The composition of Claim 9 wherein the cationic surfactants are selected from the group consisting of 1 ,2-dioleoyl-3-trimethylammonium-propane

(DOTAP), dimethyldioctadecylammonium bromide (DDAB),

N-[1-(1 ,2-dioleoyloxy)propyl]-N,N,N-trimethylammonium chloride

(DOTMA), 1 ,2-dioleoyl-3-ethylphosphocholine (DOEPC) and 3β-[N-

[(N',N'-dimethylamino)ethan]carbamoyl]cholesterol (DC-Choi).

14. The composition of Claim 9 wherein the cationic surfactants are selected from the group consisting of cholic acids, their salts and derivatives; deoxycholic acids, their salts and derivatives; chenocholic acids, their salts and derivatives; ursodeoxycholic acids, their salts and derivatives; and lithocholic acids, their salts and derivatives.

15. The composition of Claim 8 wherein the oily contrast medium is iodized poppy seed oil, and the aqueous contrast medium is iopamidol.

16. The composition of Claim 1 or Claim 2 including an additional anticancer drug selected from the group consistin gof doxorubicin (adriamycin), 5- fluorouracil, carboplatin, cisplatin, carmustine, dacabazine, etoposide, Vinorelbine, Topotecan, Irinotecan and Estramustine.

17. The composition of Claim 16 for the treatment of hepatoma by transcatheter arterial chemoembolization.

18. The composition of Claim 7 including an additional anticancer drug selected from the group consisting of doxorubicin (adriamycin), 5- fluorouracil, carboplatin, cisplatin, carmustine, dacabazine, etoposide,

Vinorelbine, Topotecan, Irinotecan and Estramustine.

19. The composition of Claim 18 for the treatment of hepatoma by transcatheter arterial chemoembolization.

20. The composition of Claim 8 for the treatment of hepatoma by transcatheter arterial chemoembolization.

21. The composition of Claim 8 including an additional anticancer drug selected from the group consisting of doxorubicin (adriamycin), 5- fluorouracil, carboplatin, cisplatin, carmustine, dacabazine, etoposide, Vinorelbine, Topotecan, Irinotecan and Estramustine.

22. The composition of Claim 21 for the treatment of hepatoma by transcatheter arterial chemoembolization.

23. A method of preparing a mixed composition solubilizing paclitaxel for chemoembolization comprising the steps of 1) solubilizing 0.01 ~ 1 % (w/v) of paclitaxel in an oily contrast medium and 2) adding 0.1 - 50 % (v/v) of aqueous contrast medium.

24. A method of preparing a water-in-oil type paclitaxel emulsion composition comprising the steps of 1) solubilizing 0.01 ~ 1 % (w/v) of paclitaxel in an oily contrast medium, 2) adding 0.1 ~ 50 % (v/v) of aqueous contrast medium and 3) mixing homogeneously the oily contrast medium phase and aqueous contrast medium by applying physical force.

25. The method of Claim 23 or Claim 24 wherein the oily contrast medium is an iodized oil of iodine content ranging 30 ~ 50 % by weight selected from the group consisting iodized poppy seed oil including Lipiodol and Ethiodol and iodized soybean oil.

26. The method of Claim 25 wherein the iodine content of the oily contrast medium is 35 ~ 48 % by weight.

27. The method of Claim 26 wherein the iodized oil is iodized poppy seed oil.

28. The method of Claim 23 or Claim 24 wherein the aqueous contrast medium is selected from the group consisting of Metrizamide, Diatrizoate, loxaglate, lopentol, lopamidol, lomeprol, lotrolan, lohexol, loversol, loxilan, lopromide, lodixanol and lobitridol.

29. The method of Claim 27 wherein the aqueous contrast medium is selected from the group consisting of Metrizamide, Diatrizoate, loxaglate, lopentol, lopamidol, lomeprol, lotrolan, lohexol, loversol, loxilan, lopromide, lodixanol and lobitridol.

30. The method of Claim 27 wherein the aqueous contrast medium is iopamidol.

31. The method of Claim 29 wherein the aqueous contrast medium is iopamidol.

32. The method of Claim 23 or Claim 24 including the step of mixing the sterilized oily contrast medium and paclitaxel under sterilized conditions or the step of sterilizing the mixture after preparation by EO gas or gamma ray.

33. The method of Claim 23 or Claim 24 wherein 0.0001 - 20 % by weight of emulsifier was additionally included.

34. The method of Claim 34 wherein the emulsifier is selected from the group consisting of phospholipids, non-ionic surfactants, anionic surfactants, cationic surfactants and bile salts.

35. The method of Claim 34 wherein the phospholipids are selected from the group consisting of phosphatidylcholines and their derivatives, phosphatidylethanolamines and their derivatives and phosphatidylserines and their derivatives, or polymeric lipid where the hydrophilic polymers are covalently-bonded to a phospholipid.

36. The method of Claim 34 wherein the non-ionic surfactants are selected from the group consisting of poloxamers (also known as pluronic: a copolymer of polyoxyethylene and polyoxypropylene), hydrogenated castor oils (HCO), sorbitan esters (Span) and polyoxyethylene-sorbitan fat acid esters (Tween) and polyoxyehtylene ethers (Brij).

37. The method of Claim 34 wherein the anionic surfactants are selected from the group consisting of phosphatidylserines and their derivatives, phosphatidic acids and their derivatives and sodium dodecyl sulfate.

38. The method of Claim 34 wherein the cationic surfactants are selected from the group consisting of 1 ,2-dioleoyl-3-trimethylammonium-propane (DOTAP), dimethyldioctadecylammonium bromide (DDAB), N-[1-(1 ,2-dioleoyloxy)propyl]-N,N,N-trimethylammonium chloride

(DOTMA), 1 ,2-dioleoyl-3-ethylphosphocholine (DOEPC) and 3β-[N-

[(N',N'-dimethylamino)ethan]carbamoyl]cholesterol (DC-Choi).

39. The method of Claim 34 wherein the cationic surfactants are selected from the group consisting of cholic acids, their salts and derivatives; deoxycholic acids, their salts and derivatives; chenocholic acids, their salts and derivatives; ursodeoxycholic acids, their salts and derivatives; and lithocholic acids, their salts and derivatives.

40. The method of Claim 23 or Claim 24 wherein an additional anticancer drug selected from the group consisting of doxorubicin, 5-fluorouracil, carboplatin, cisplatin, carmustine, dacabazine, etoposide, Vinorelbine,

Topotecan, Irinotecan and Estramustine is solubilized in the aqueous contrast medium.

41. The method of Claim 33 wherein an additional anticancer drug selected from the group consisting of doxorubicin, 5-fluorouracil, carboplatin, cisplatin, carmustine, dacabazine, etoposide, Vinorelbine, Topotecan, Irinotecan and Estramustine is solubilized in the aqueous contrast medium.