USE OF 3,4-DIPHENYL CHROMANS FOR THE MANUFACTURE OF A PHARMACEUTICAL COMPOSITION FOR THE TREATMENT OR PROPHYLAXIS OF PROSTATIC CARCINOMA

Abstract: The present invention provides novel uses of compounds of formula (I) wherein R<1>, R<4> and R<5> are individually hydrogen, hydroxy, halogen, trifluoromethyl, C1-6-alkyl, C1-6-alkoxy or (tertiary amino)(C1-6-alkoxy); and R<2> and R<3> are individually hydrogen or C1-6-alkyl, or as a pharmaceutically acceptable salt thereof in combination with a pharmaceutically acceptable carrier for the manufacture of a pharmaceutical composition for the treatment or prophylaxis of prostatic carcinoma.

Description: Use of 3,4-diphenyl chromans for the manufacture of a pharmaceutical composi ¬ tion for the treatment or prophylaxis of prostatic carcinoma. FIELD OF THIS INVENTION The present invention relates to the use of compounds of the general formula I for the treatment of patients suffering from prostatic carcinoma and prophylaxis hereof. The present invention also embraces pharmaceutical compositions com¬ prising these compounds and methods of using the compounds and their phar- maceutical compositions. BACKGROUND OF THIS INVENTION Cancer of the prostate is the second most common malignancy in men and is the third most common cause of cancer death in men older than age 55. The cause is unknown, but hormonal factors appear to play a role in the development of prostatic cancer. The disease does not occur in eunuchs castrated before puber¬ ty, and its incidence is low in patients with hyperestrogenism due to liver cirrho¬ sis. Most cases is diagnosed after the age of 50 years, but they can be seen in younger adults. Total prostatoseminovesicolectomy is the oldest treatment for carcinoma of the prostate. The operation may cause impotence and has its clea¬ rest indication only in stage B disease. Radiation therapy has major chronic com¬ plications after full courses of treatment and include impotence, chronic proctitis, rectal strictures, rectal fistulas and rectal bleeding. Additionally, current data suggest that radiotherapy may be less curative than radical prostatectomy. An- drogen deprivation by means of bilateral orchiectomy, diethylstilbestrol therapy or combined orchiectomy plus diethylstilbestrol has been the standard form of treatment for carcinoma of the prostate for many years. However, recent pro¬ spective studies have not demonstrated a clear cut beneficial effect of this type of treatment. Furthermore death from cardiovascular disease appear to be more frequent in patients treated with large doses of diethylstilbestrol. Complete re- sponse to ordinary chemotherapy (e.g. estramustine phosphate, prednimusitne and cispiatin) is rare and only one-tenth of stage D patients have an objective partial response. Taken together, therefore, the treatment possibilities for this common malignancy is poor. Centchroman is a non-steroidal compound known to have antiestrogenic activity. It is in use in India as an oral contraceptive (see, for example, Salman et al., U.S. Patent Specification No. 4,447,622; Singh et al., Acta Endochnal (Copenh) 1 26 (1 992), 444 - 450; Grubb, Qua. Ωpjn Obstet Gynecol (1 991 ), 491 - 495; San- karan et al., Contraception 9 (1 974), 279 - 289; Indian Patent Specification No. 1 291 87). Centchroman has also been investigated as an anti-cancer agent for treatment of advanced breast cancer (Misra et al., Int J Cancer 43 ( 1 989), 781 - 783. Recently, centchroman as a racemate has been found as a potent choleste¬ rol lowering pharmaceutical expressed by a significant decrease of the serum concentrations (S.D. Bain et al., J Min B-On Bes 3 d 994), S 394). U.S. patent 5,453,442 describes methods of lowering serum cholesterol and in¬ hibiting smoother muscle cell proliferation in humans and inhibiting uterine fibroid disease and endometriosis in women by administering compounds of formula I as shown therein. Furthermore US patent 5,280,040 describes methods and phar¬ maceutical compositions for reducing bone loss using 3,4-diarylchromans and their pharmaceutically acceptable salts. There is no disclosure in the patents of using the compounds to treat prostatic carcinoma. One object of the present invention is to provide compounds which can effecti¬ vely be used in the treatment or prophylaxis of prostatic carcinoma. BRIEF DESCRIPTION OF THIS INVENTION It has, surprisingly, been found that compounds of the general formula I as sta¬ ted in claim 1 can be used in the treatment or prophylaxis of prostatic carcinoma. DFTAII FP DESCRIPTION OF THIS INVENTION The present invention is based in part on the discovery that a representative 3,4- diarylchroman, centchroman (3,4-trans-2,2-dimethyl-3-phenyl-4-[p-(beta-- pyrrolidinoethoxy)phenyl]-7-methoxychroman) effectively decreases prostate weight, inter alia in rats and has been demonstrated to be a partial estrogen re¬ ceptor agonist. As an increase in prostate weight is generally seen in patients with prostate carcinomas and since estrogen receptor stimulation is the most ef- fective therapy, these data thus indicate that the 3,4-diarylchromans are useful as therapeutic agents against prostatic carcinoma in mammals, including prima¬ tes such as humans. Within the present invention, compounds of formula I or their pharmaceutically acceptable salts are used for the treatment or prophylaxis of prostatic carcinoma in a patient. Within formula I, R 1 , R 4 and R 5 are individually hydrogen, hydroxy, halogen, trifluoromethyl, C^-alkyl, C^-alkoxy or (tertiary aminoMC^-alkoxy); and R 2 and R 3 are individually hydrogen or a C^-alky!. As used herein, the term "C^-alkyl" includes straight and branched chain alkyl radicals containing from 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-amyl, sec- amyl, n-hexyl, 2-ethylbutyl, 2,3-dimethylbutyl and the like. The term "C 6 - alkoxy" includes straight and branched chain alkoxy radicals containing from 1 to 6 carbon atoms, such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy, n-amyloxy, sec-amyloxy, n-hexyloxy, 2-ethylbutoxy, 2,3- dimethylbutoxy and the like. "Halogen" includes chloro, fluoro, bromo and iodo. Herein, the term "(tertiary aminoMC L g-alkoxy) " " s a C,. 6 -alkoxy group which is substituted by a tertiary amino radical. The tertiary amino radical may be a N,N- dialkylamine such as a N,N-dimethylamino, N,N-diethylamino, N,N-dipropylamino and N,N-dibutylamino or a polymethyleneimine, e.g., piperidine, pyrrolidine, N- methylpiperazine or morpholine. Preferred compounds include those in which R^ is C^-alkoxy; R 2 and R 3 are C,. 6 -alkyl, especially methyl; R 4 is hydrogen; and R ^ is (tertiary aminoXC^ g -alkoxy) of the polymethyleneimine type. Within particu- larly preferred embodiments, R^ is in the 7-position and is C^-alkoxy, particu¬ larly methoxy; each of R 2 and R 3 is methyl, R 4 is hydrogen, and R° is in the 4- position and is a (tertiary aminoMC Lβ -alkoxy) radical such as 2-(pyrrolidin-1 - yDethoxy with formula II To be included by this invention are all pharmaceutically acceptable salts of the mentioned compounds of formula I. It is preferred to use the compounds of formula I in the transconfiguration. These compounds may be used as racemic mixtures, or the isolated d- or I- enantiomers may be used. The trans-l-enantiomers are more preferred. A particularly preferred compound for use within the present invention is cen¬ tchroman having the formula IV Although only one enantiomer is shown, it will be understood that the formula IV is used herein to designate the transconfiguration of the 3- and 4-phenyl groups and that both the d- and l-enantiomers, as well as the racemic mixture, are inclu¬ ded. 3,4-diarylchromans are prepared according to known methods, such as those di- sclosed in U.S. Patent Specification No. 3,340,276 to Carney et al., U.S. Patent Specification No. 3,822,287 to Bolger, and Ray et al., J Med Chem 1 9 ( 1 976), 276 - 279, the contents of which are incorporated herein by reference. Conver¬ sion of the cis isomer to the trans configuration by means of an organometallic base-catalyzed rearrangement is disclosed in U.S. Patent Specification No. 3,822,287. The optically active d- and l-enantiomers may be prepared as disclo¬ sed by Salman et al. in U.S. Patent Specification No. 4,447,622 (incorporated herein by reference) by forming an optically active acid salt which is subjected to alkaline hydrolysis to produce the desired enantiomer. If R 2 is different from R 3 and R 4 is different from R^, the general formula I covers 8 optical isomers. Within the present invention, 3,4-diarylchromans of formula I may be prepared in the form of pharmaceutically acceptable salts, especially acid-addition salts, in¬ cluding salts of organic acids and mineral acids. Examples of such salts include salts of organic acids such as formic acid, fumaric acid, acetic acid, propionic a- cid, glycolic acid, lactic acid, pyruvic acid, oxalic acid, succinic acid, malic acid, tartaric acid, citric acid, benzoic acid, salicylic acid and the like. Suitable inorga¬ nic acid-addition salts include salts of hydrochloric, hydrobromic, sulphuric and phosphoric acids and the like. The acid addition salts may be obtained as the di¬ rect products of compound synthesis. In the alternative, the free base may be dissolved in a suitable solvent containing the appropriate acid, and the salt isola¬ ted by evaporating the solvent or otherwise separating the salt and solvent. 3,4-diarylchromans of formula I and their salts are useful within human and vete¬ rinary medicine, for example, in the treatment of patients suffering from prostatic carcinoma. For use within the present invention, 3,4-diarylchromans of formula I and their pharmaceutically acceptable salts are formulated with a pharmaceuti¬ cally acceptable carrier to provide a medicament for parenteral, oral, nasal, rectal, subdermal or intradermal or transdermal administration according to conventional methods. Formulations may further include one or more diluents, fillers, emul- sifiers, preservatives, buffers, excipients, etc. and may be provided in such forms as liquids, powders, emulsions, suppositories, liposomes, transdermal patches, controlled release, dermal implants, tablets, etc. One skilled in this art may for¬ mulate the compounds of formula I in an appropriate manner, and in accordance with accepted practices, such as those disclosed in Remington's Pharmaceutical Sciences. Gennaro, ed., Mack Publishing Co., Easton, PA, 1 990. Oral administration is preferred. Thus, the active compound of formula I is prepa¬ red in a form suitable for oral administration, such as a tablet or capsule. Typi¬ cally, a pharmaceutically acceptable salt of the compound of formula I is com- bined with a carrier and moulded into a tablet. Suitable carriers in this regard in¬ clude starch, sugars, dicalcium phosphate, calcium stearate, magnesium stearate and the like. Such compositions may further include one or more auxiliary sub¬ stances, such as wetting agents, emulsifiers, preservatives, stabilizers, colouring additives, etc. Pharmaceutical compositions containing a compound of formula I may be admini¬ stered one or more times per day or week. An effective amount of such a phar¬ maceutical composition is the amount that provides a clinically significant effect against prostatic carcinoma. Such amounts will depend, in part, on the particular condition to be treated, age, weight, and general health of the patient, and other factors evident to those skilled in the art. A typical daily dose will contain a non- toxic dosage range of from about 0.001 to about 75 mg/kg patient per day of a compound of the present invention. The pharmaceutical compositions containing a compound of formula I may be administered in unit dosage form one or more times per day or week. In the al¬ ternative, they may be provided as controlled release formulations suitable for dermal implantation. Implants are formulated to provide release of active com¬ pound over the desired period of time, which can be up to several years. Con- trolled-release formulations are disclosed by, for example, Sanders et al., J Pharm Sci 7_3_ ( 1 964), 1 294 - 1 297, 1 984; U.S. Patent Specification No. 4,489,056; and U.S. Patent Specification No. 4,21 0,644, which are incorpora¬ ted herein by reference. The following examples are offered by way of illustration, not limitation. Examples of preferred compounds of formula I are centchroman as a racemic mixture and as isolated l-centchroman and d-centchroman enantiomers. Further¬ more, 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 -yl)ethoxy)phenyl]-7- hydroxychroman is a preferred compound. The more preferred compound is isola- ted l-centchroman (|-3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 - yl)ethoxy)phenyl]-7-methoxychroman). Examples of pharmaceutically acceptable acid addition salts are salts with non- toxic acids, either inorganic acids such as hydrochloric acid, sulphuric acid and phosphoric acid, or organic acids such as formic acid, fumaric acid, acetic acid, propionic acid, succinic acid, gluconic acid, lactic acid, citric acid, ascorbic acid, benzoic acid, embonic acid, methanesulphonic acid and malonic acid. The present invention is further illustrated by the following examples which, however, are not to be construed as limiting the scope of protection. The fea- tures disclosed in the foregoing description and in the following examples may, both separately and in any combination thereof, be material for realising the in¬ vention in diverse forms thereof. Example 1 Sixty sexually mature male Sprague-Dawley rats were assigned to one of the following five treatment groups ( 1 2 rats per group): Dsaline, 2) l-centchroman 0.025 mg/kg/day, 3) l-centchroman 0.1 25 mg/kg/day, 4) l-centchroman 0.625 mg/kg/day and 5) l-centchroman 3.1 25 mg/kg/day. The doses were administered three times per week for 1 3 weeks by oral gavage. At the conclusion of the ex¬ periment and autopsy was performed, the prostate gland and testes were isola¬ ted and weighed. L-centchroman had no effect on the average testis weight between the groups. However, a marked and dose-dependent effect on the prostate gland was obser- ved as illustrated in Table 1 . Table 1 . Effect of l-centchroman on prostate gland weight in Sprague-Dawley rats Treatment Prostate gland (g) Saline 0.639 ± 0.239 l-centchroman 0.025 mg/kg/day 0.669 ± 0.149 l-centchroman 0.1 25 mg/kg/day 0.472 ± 0.1 26 * l-centchroman 0.625 mg/kg/day 0.430 ± 0.1 22* l-centchroman 3.1 25 mg/kg/day 0.368 ± 0.1 24* Values are mean ± SD. * indicate significant reduction of prostate gland weight compared to saline treated rats.

Claims: CLAIMS 1 . The use of compounds of the general formula I wherein R 1 , R 4 and R 5 are individually hydrogen, hydroxy, halogen, tri¬ fluoromethyl, and R 2 and R 3 are individually hydrogen or C,. 6 -alkyl, or as a pharmaceutically acceptable salt thereof in combination with a pharmaceutically acceptable carrier for the manu¬ facture of a pharmaceutical composition for the treatment or prophylaxis of pro- static carcinoma. 2. The use, according to claim 1 , wherein R 1 in the compound used is C,. 6 - alkoxy, R 2 and R 3 are C,. 6 -alkyl, R 4 is hydrogen and R 5 is (tertiary amino) C^-al- koxy. 3. The use according to any one of claims 1 or 2 wherein R 1 is methoxy. 4. The use according to any one of claims 1 -3 wherein R 2 is methyl. 5. The use according to any one of claims 1 -4 wherein R 3 is methyl. 6. The use according to any one of claims 1 -5 wherein R 4 is hydrogen. 7. The use according to any one of claims 1 -6 wherein R 5 is a group as sta¬ ted in formula II below: 8. The use according to any one of claims 1 -7 wherein said compound is an isolated d- or l-enantiomer. 9. The use according to any one of the preceding claims wherein said com¬ pound has the general formula III as stated below: wherein R 1 , R 2 , R 3 , R 4 and R 5 each are as defined in above claim 1 10. The use according to anyone of the preceding claims wherein said com¬ pound is 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 -yl)ethoxy)phenyl]- 7-hydroxychroman. 1 1 . The use according to anyone of the preceding claims wherein said com¬ pound is an isolated l-enantiomer. 1 2. The use according to claim 1 wherein said compound is centchroman 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 -yl)ethoxy)phenyl]-7- methoxychroman having the formula IV as stated below: 1 3. The use according to claim 1 2 wherein said compound is an isolated I- enantiomer of 3,4-trans-2,2-dimethyl-3-phenyl-4-[4-(2-(pyrrolidin-1 - yl)ethoxy)phenyl]-7-methoxychroman. *- 1 4. The use according to any one of the preceding claims wherein said com¬ position is in a form suitable for oral administration. 1 5. The use according to any one of the preceding claims wherein said com¬ pound is administered as a dose in a range from about 0.001 to 75 mg/kg pa¬ tient per day. 1 6. The use according to any one of the preceding claims wherein said com¬ position is administered one or more times per day or week. 1 7. The use according to any one of the preceding claims wherein said com¬ position is in the form of a dermal implant. 1 8. Method for treatment and prophylaxis of prostatic carcinoma comprising administering to a patient a clinically effective amount of a compound of above formula I stated to be used in any of the preceding use claims, or a pharmaceuti¬ cally acceptable salt thereof in an amount sufficient to treat or prevent prostatic carcinoma. 1 9. A method of treating or preventing prostatic carcinoma which method comprises administering a clinically effective amount of compounds and pharma¬ ceutically acceptable compositions, according to previous claims to a patient in need of such a treatment. 20. Any novel feature or combination of features described herein.

Inventors: CHRISTENSEN NIELS DYHR, GULDHAMMER BIRGITTE HJORT, KORSGAARD NIELS, SHALMI MICHAEL, CHRISTENSEN, NIELS, DYHR, GULDHAMMER, BIRGITTE, HJORT, KORSGAARD, NIELS, SHALMI, MICHAEL
Applicants: NOVONORDISK AS, NOVO NORDISK A/S
Application year: 1997
Main classification: A61K31
IPC codes: A61K31, A61P15, A61P35, C07D311