Use of steroid derivatives in the treatment of endometriosis

Abstract: A remedy for endometriosis comprising, as an active ingredient, 14α-hydroxy-4-androstene-3,6,17-trione or an ester derivative thereof, can effectively treat endometriosis by the strong aromatase-inhibitory activity without giving serious side effects.

Description: Background of the Invention (1) Field of the Invention The present invention relates to the use of a remedy for endometriosis. (2) Description of the Prior Art Endometriosis appears as a product of atopic proliferation of endometrium. Internal endometriosis includes adenomyosis of uterus and endosalpingosis, and external endometriosis includes endometriosis of pelvic cavity and ectopic endometriosis. Endometriosis appears at a high incidence in females of 20-45 years old and its incidence has shown steady increase in recent years. It is said that the symptom of endometriosis is seen in 15-20% of females of 20-35 years old. Endometriosis is generally accompanied by dysmenorrhea and has a close relation to acyesis. Endometriosis is generally treated by pseudomenopausal treatment using danazol [Bonzal (trade name) manufactured by Tokyo Tanabe Seiyaku]. It is also tried to administer buserelin [Suprecur (trade name) manufactured by Hoechst Japan] which is a LH-RH derivative. However, it is pointed out that danazol gives side effects such as dyshepatia, masculinization and the like and buserelin gives side effects such as hyposexuality, hot flushes and the like. When medicinal treatments show no effect, a surgical treatment such as hysterectomy, lesion removal or the like is adopted but is not a desirable approach in view of the patient's response, the after effect, etc. Therefore, development of a drug having a novel effect is desired. Meanwhile, the present inventors have studied for many years on aromatase (a steroidogenesis enzyme) inhibitor. It is known that 14α-hydroxy-4-androstene-3,6,17-trione and ester derivatives thereof have a strong aromatase-inhibitory activity. These compounds are disclosed in Japanese Patent Application Laid-Open Nos. 192794/1988, 131193/1989, etc. The present inventors made study on the pharmacological activities of the compounds and found that the aromatase-inhibitory activity shown by the compounds is effective for treatment of endometriosis. Summary of the Invention The object of the present invention is to provide the use of a compound for the manufacture of a medicament for the treatment of endometriosis, said compound showing a strong aromatase-inhibitory activity. The above object of the present invention can be achieved by providing the use of the compound 14α-hydroxy-4-androstene-3,6,17-trione or an ester derivative thereof for the manufacture of a medicament for the treatment of endometriosis. Detailed Description of Preferred Embodiments The active ingredients used in the present invention are represented by the following structural formulas wherein R represents a -OCOR₁ group (R₁ is a C₁-C₆ alkyl group, an aryl group or an aralkyl group). The alkyl group includes, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, isobutyl, tert-butyl and isopropyl. The aryl group includes, for example, phenyl and tolyl. The aralkyl group includes, for example, benzyl and phenylethyl. The ester group thereof (-OCOR₁) includes, for example, the followings. The ester derivative is preferably a propionate (6-OAp) or a benzoate (6-OAb). The above compounds can be synthesized by the methods described in Japanese Patent Application Laid-Open Nos. 192794/1988 and 131193/1989. That is, 14α-hydroxy-4-androstene-3,6,17-trione is synthesized from 6β,14α-dihydroxy-4-androstene-3,17-dione according to an ordinary oxidation reaction (for example, Jones' oxidation reaction) and then is reacted with propionic anhydride or benzoyl chloride to obtain a propionate or a benzoate. These compounds are made into pharmaceutical preparations and then administered in forms such as oral agent, suppository, and injection. In preparing an oral agent, there are used carriers such as mannitol, lactose, starch, magnesium stearate, cellulose, glucose and saccharose; and an absorption accelerator can be added as necessary. The oral agent can be used in combination with a conventional remedy for endometriosis. In treatment of endometriosis, the compound is administered daily for 1-6 months in an amount of 10 mg to 1 g per day. The use of the compound for the manufacture of a medicament for the treatment of endometriosis according to the present invention specifically inhibits aromatase (a steroidogenesis enzyme) to reduce estradiol (Ez), thereby exhibiting a therapeutic effect for endometriosis. This action mechanism is different from those of danazol and buserelin, and the active compound against endometriosis provides very high utility. 6-OA has very low toxicity and animal tests indicated its LD₅₀ is more than 2,000 mg/kg. The ester derivatives of 6-OAp have low toxicity as well. Therefore, these compounds can provide a very safe remedy. The present invention is hereinafter described in more detail by way of Examples and Test Examples. Example 1 (Tablets) 14α-Hydroxy-4-androstene-3,6,17-trione (6-OA) 200 mg Hydroxy propyl cellulose (HPC) 30 mg Lactose 67 mg Magnesium stearate 3 mg Total 300 mg The above components were mixed to prepare tablets so that each tablet contained them in the above amounts. Example 2 (Tablets) 6-0A 200 mg HPC 30 mg Hydroxy propyl methyl cellulose (TC-5) 6 mg Lactose 61 mg Magnesium stearate 3 mg Total 300 mg The above components were mixed to prepare tablets so that each tablet contained them in the above amounts. In this case, an aqueous TC-5 solution was used as a binder, and granules were prepared according to a wet method and made into tablets. Example 3 (Tablets) 14α-Hydroxy-androsta-4,6-diene-3,17-dione-6-propionate (6-OAp) 235.4 mg HPC 30 mg Lactose 80.6 mg Magnesium stearate 4 mg Total 350 mg The above components were mixed to prepare tablets so that each tablet contained them in the above amounts. Example 4 (Tablets) 6-OAp 235.4 mg HPC 30 mg TC-5 6 mg Lactose 74.6 mg Magnesium stearate 4 mg Total 350 mg The above components were mixed to prepare tablets so that each tablet contained them in the above amounts. In this case, an aqueous TC-5 solution was used as a binder, and granules were prepared according to a wet method and made into tablets. Example 5 (Capsules) 6-OA 200 mg HPC 30 mg Lactose 116 mg Magnesium stearate 4 mg Total 350 mg The above components were mixed and packed into hard capsules specified by the Japanese Pharmacopoeia, to obtain each capsule containing the above components in the above amounts. Example 6 (Capsules) 6-OA 200 mg HPC 30 mg TC-5 8 mg Lactose 108 mg Magnesium stearate 4 mg Total 350 mg The above components were mixed and packed into hard capsules specified by the Japanese Pharmacopoeia, to obtain each capsule containing the above components in the above amounts. In this case, an aqueous TC-5 solution was used as a binder, and granules were prepared according to a wet method and packed into capsules. Example 7 (Capsules) 6-0Ap 235.4 mg HPC 30 mg Lactose 130.6 mg Magnesium stearate 4 mg Total 400 mg The above components were mixed and packed into hard capsules specified by the Japanese Pharmacopoeia, to obtain each capsule containing the above components in the above amounts. Example 8 (Capsules) 6-OAp 235.4 mg HPC 30 mg TC-5 8 mg Lactose 122.6 mg Magnesium stearate 4 mg Total 400 mg The above components were mixed and packed into hard capsules specified by the Japanese Pharmacopoeia, to obtain each capsule containing the above components in the above amounts. In this case, an aqueous TC-5 solution was used as a binder, and granules were prepared according to a wet method and packed into capsules. Test Example 1 In this Test Example, effects of administration of 6-OA and ester compounds thereof on estradiol (E₂) reduction were examined. [Test method] Test (1) Comparison by subcutaneous administration 20 SD strain female rats of 8-week old were used as test animals. They were divided into four groups each consisting of 5 rats. To all the rats was subcutaneously injected pregnant mare serum gonatropin (PMSG) in an amount of 100 IU/body once every other day (6 times in total). In the beforenoon of the next day of the final (6th) administration of PMSG, 0.5 ml of a solvent, 50 mg/kg of 6-OA, 50 mg/kg of 6-0Ap and 50 mg/kg of 6-OAb were subcutaneously administered to group I (control group), group II, group III and group IV, respectively. After 3 hours from the administration, the rats were subjected to abdomen opening under etherization and then to exsanguination from the main vein. The blood collected from each rat was subjected to serum separation, and the E₂ in the serum was determined by radioimmunoassay. Incidentally, a physiological saline solution containing 0.3% of hydroxy propyl cellulose (HPC) was used as the solvent. 6-OA, 6-OAp and 6-OAb were each suspended in the solvent in such a concentration that the administration amount of the resulting suspension per rat became 0.5 ml. Test (2) Comparison by oral administration The type, age, number and grouping of test animals were the same as in Test (1). To all the rats was subcutaneously injected PMSG, in the same manner as in Test (1), in an amount of 100 IU/body once every other day (6 times in total). In the beforenoon of the next day of the final (6th) administration of PMSG, 0.5 ml of a solvent, 100 mg/kg of 6-OA, 100 mg/kg of 6-0Ap and 100 mg/kg of 6-OAb were orally administered to group I (control group), group II, group III and group IV, respectively. Aftr 6 hours from the administration, the rats were subjected to exsanguination. The blood collected from each rat was subjected to serum separation, and the E₂ in the serum was determined by radioimmunoassay. The solvent used was the same as in Test (1). 6-OA, 6-OAp and 6-OAb were each suspended in the solvent in such a concentration that the administration amount of the resulting suspension per rat became 0.5 ml. [Results] The E₂ concentrations in serum of Test (1) and Test (2) are shown in Table 1 and Table 2. Test (1) Subcutaneous administration I (HPC) II (6-OA) III (6-OAp) IV (6-OAb) Average 0.572 0.262 0.230 0.390 S.D. ±0.079 ±0.049 ±0.035 ±0.083 (unit: ng/ml) Test (2) Oral administration I (HPC) II (6-OA) III (6-OAp) IV (6-OAb) Average 0.522 0.291 0.226 0.422 S.D. ±0.072 ±0.038 ±0.036 ±0.041 (unit: ng/ml) [Conclusion] The 6-OA group, the 6-OAp group and the 6-OAb group, as compared with the control group, showed a strong E₂-reducing effect in both cases of subcutaneous administration and oral administration. The 6-OAp group showed a stronger E₂-reducing effect than the 6-OA group and the 6-OAb group. Test Example 2 In this Test example, effect of administration of 6-OAp on model rats of endometriosis was examined. [Test Method] SD strain female rats of 7-week old weighing 170-210 g were used as test animals. In these rats, an endometrial segment (about 5 mmx5 mm) was removed from the left uterine horn and autoplanted under the left renal capsule, and formation of cysts in the transplanted endometrium was examined. Those rats which had developed cysts of 0.5-2.0 mm in height in the transplanted endometrium, were used for test. The rats were divided into three groups. To group I (control group) was orally administered a physiological saline solution containing 0.3% of hydroxy propyl cellulose (HPC) daily in an amount of 0.5 ml/day. To group II was orally administered 6-OAp daily in an amount of 100 mg/kg/day. In this case, 6-OAp was suspended in a physiological saline solution containing 0.3% of HPC in such a concentration that the administration amount of the resulting suspension per rat became 0.5 ml. Group III (positive control) was subjected to ovary removal. Each rat was subjected to abdomen opening after 3 weeks from the start of administration or after the ovary removal to examine the presence of cysts. Chi-square test was used for the statistical analysis of the test data obtained. [Test results] The results of the above test are shown in Table 3. 6-OAp administration Cysts present Cysts absent Total Disappearance Control group 20 rats 2 rats 22 rats 9% 6-OAp group 13 9 22 41 Ovary-removed group 0 9 9 100 [Conclusion] 6-OAp was effective for experimental endometriosis of rats when orally administered daily for 3 weeks in an amount of 100 mg/kg/day. The present invention can provide the use of a compound for the manufacture of a medicament for the treatment of endometriosis, said compound, as an active ingredient of the medicament, being 14α-hydroxy-4-androstene-3,6,17-trione or an ester derivative thereof. This remedy has an action mechanism different from those of conventional remedies for endometriosis and can treat endometriosis effectively without giving serious side effects. As a result, endometriosis can be treated effectively without using any surgical treatment.

Claims: Use of the compound 14α-hydroxy-4-androstene-3,6,17-trione, represented by the following general formula (I), or an ester derivative thereof, represented by the following general formula (II), wherein R represents a -OCOR₁-group with R₁ being a C₁-C₆ alkyl group, an aryl group or an aralkyl group, for the manufacture of a medicament for the treatment of endometriosis. The use of claim 1, wherein the compound, represented by the general formula (I), is 14α-hydroxy-4-androstene-3,6, 17-trione. The use of claim 1, wherein the compound, represented by the general formula (II), is 14α-hydroxy-4-androstene-3, 17-dione-6-propionate.

Inventors: FUJISE NOBUAKI, HONDA NOBUYOSHI, TAKAOKA HIROAKI, YAMASHITA YASUSHI, YOSHIHAMA MAKOTO, FUJISE, NOBUAKI, HONDA, NOBUYOSHI, TAKAOKA, HIROAKI, YAMASHITA, YASUSHI, YOSHIHAMA, MAKOTO
Applicants: SNOW BRAND MILK PROD CO LTD, SNOW BRAND MILK PRODUCTS CO., LTD.
Application year: 1991
Main classification: A61K31
IPC codes: C07J1, A61K31, A61P13, A61P15