RS56491B1 - ENDOMETRIUM PROLIFERATION COMPOSITIONS AND PROCEDURES - Google Patents

Description

Description

FIELD OF INVENTION

[0001] The present invention relates to compositions and methods for suppressing endometrial proliferation. More specifically, the present invention relates to compositions containing one or more progesterone antagonists for suppressing endometrial proliferation.

BASIS OF THE INVENTION

[0002] Estrogens are a group of hormones essential for various physiological processes including uterine and breast development, maintaining bone density and cardiovascular protection through their positive effect on lipid profiles. The effects of estrogen are mediated through its binding to estrogen receptors in the nucleus. According to the classical model, an unoccupied estrogen receptor in the nucleus, after estrogen binding, acquires the ability to interact with DNA sequences within the promoters of estrogen-responsive genes. The DNA-bound estrogen receptor modulates the transcription of these genes, either positively or negatively.

[0003] Estrogen is known to have a hyperproliferative effect on breast and uterine tissue. Administration of unopposed estrogen to menopausal women, for example, has been shown to lead to endometrial hyperplasia and endometrial cancer. In contrast, progesterone potently neutralizes estrogen-dependent endometrial proliferation and cancer development. Therefore, to counteract the effects of unopposed estrogen, progestin is commonly prescribed as part of hormone replacement therapy (HRT). However, a large clinical study from the Women's Health Initiative recently found that the combination of conjugated estrogen and medroxyprogesterone acetate increased the risk of developing cardiovascular disease, stroke, pulmonary embolism, and breast cancer. In addition, experimental data in surgically menopausal macaque monkeys showed that a regimen of combined estrogen and progesterone led to higher levels of breast proliferation and hyperplasia than estrogen alone. Progestin coadministration is also associated with breakthrough bleeding, further limiting its suitability as an agent for use against the hyperproliferative effects of estrogen.

[0004] Many compounds are known in the art that affect estrogen-dependent activation of the estrogen receptor. Depending on various factors, these compounds can be completely estrogenic, in that they mimic estrogen, completely anti-estrogenic, in that they block the effects of estrogen, or they can be somewhere in between. Compounds that exhibit mixed estrogenic and antiestrogenic properties are referred to as selective estrogen receptor modulators (SERMs). SERMs exert their estrogenic or antiestrogenic effects in a tissue-specific manner. The mechanism underlying this tissue specificity is unclear, but may involve, among others, the recruitment of corepressor and coactivator proteins whose relative expression levels vary among tissue types and tissue-specific expression of estrogen receptor isoforms α and β. The estrogen receptor α is an activator, while the estrogen receptor β can inhibit the activity of the estrogen receptor α by forming a heterodimer with it.

[0005] The dual activities of SERMs provide several potential benefits for women. The estrogenic properties of SERMs can be used to treat or prevent diseases caused by estrogen deficiency such as osteoporosis, while minimizing some of the side effects of estrogen. Conversely, the antiestrogenic properties of SERMs can be used to prevent or treat diseases such as breast cancer, where estrogenic activity is undesirable. Nevertheless, endometrial hyperplasia has been associated with SERM therapy, thus limiting its benefit.

[0006] The SERM tamoxifen, for example, has been shown to be anti-estrogenic in the breast where it blocks the proliferative effects of estrogen and has consequently found favor as a treatment for certain types of breast cancer. On the other hand, tamoxifen exerts estrogenic effects on bone and the uterus and is associated with an increased incidence of endometrial hyperplasia and endometrial cancer, limiting its utility as an antiestrogen.

[0007] A preliminary study in primates seems to indicate that antiprogestins have antiproliferative effects on the endometrium. However, there is concern that long-term treatment with antiprogestins could result in endometrial hyperplasia as a consequence of the action of unopposed estrogen. Several recent studies in adult women have found thickening of the endometrium during long-term treatment with high-dose antiprogestins, possibly due to the activity of unopposed estrogen, which does not appear to occur with low doses.

[0008] WO 01/74840 A2 describes the treatment of endometriosis with SERMs. The compounds can be applied daily.

[0009] There remains a need for a treatment regimen suitable for long-term administration that opposes the proliferative effects of estrogen while maintaining the beneficial effects of estrogen on the body.

SUMMARY OF THE INVENTION

[0010] The present invention provides a progesterone antagonist selected from 21-methoxy-17α-acetoxy-11β-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-diene-3,20-dione (CDB-4124) or 17αacetoxy-11β-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-diene-3,20-dione for use in the medical treatment of a patient by suppressing endometrial proliferation or preventing hyperproliferation of uterine cells while avoiding the adverse effects associated with stagnant or thickened endometrium, according to an intermittent dosing regimen comprising the administration of a therapeutically effective amount of a progesterone antagonist during an administration period during which the progesterone antagonist is administered daily or every other day, for a period of 1, 2, 3, 4, 5, or 6 months, then said administration during an interruption period via a continuous lack of interruption during treatment a period of time sufficient to the woman menstruates, wherein the specified period is less than the number of days during which the progesterone antagonist was previously applied, then the application of a therapeutically effective amount of the progesterone antagonist every day or every other day, for a period of 1, 2, 3, 4, 5 or 6 months, then the interruption of the said application through a continuous lack of treatment during a period of time sufficient for the woman to menstruate, and the repetition of this treatment with intermittent application in order to achieve the suppression of endometrial proliferation or the prevention of hyperproliferation of uterine cells.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]

Figure 1 is a graph showing the effect of selective progesterone receptor modulators on serum cortisol in rats.

Figure 2 is a graph showing the dose-dependent effect of CDB-4124 on serum cortisol in rats.

DETAILED DESCRIPTION OF THE INVENTION

[0012] The term "effective dose" means an amount of the active component of the composition that is sufficient to achieve the desired effect which may be, for example, suppression of endometrial proliferation or treatment of pain associated with endometriosis.

[0013] The term "selective progesterone receptor modulators" refers to compounds that affect progesterone receptor functions in a tissue-dependent manner. The compounds act as progesterone receptor antagonists in some tissues (eg, the uterus) and as progesterone receptor agonists in other tissues.

[0014] The terms "treat" or "treatment" mean therapeutic treatment and prophylactic or preventive measures, where the goal is to prevent or lower (reduce) an unwanted physiological change or disorder. For purposes of the present invention, useful or desired clinical results include, but are not limited to, symptom relief, disease severity reduction, stabilized (ie, no worsening) disease state, delay or slowing of disease progression, improvement or palliation of disease state, and remission (whether partial or complete), whether detectable or undetectable. "Treatment/treatment" can also mean prolongation of survival compared to expected survival without receiving treatment. Those in need of treatment include those who already have the condition or disorder as well as those who are susceptible to having the condition or disorder or those in whom the condition or disorder is preventable.

[0015] The term "progesterone agonist" means a compound that binds to the progesterone receptor and mimics the action of the natural hormone.

[0016] The term "progesterone antagonist" refers to compounds that bind to the progesterone receptor and inhibit the effect of progesterone.

[0017] The term "suppression" or "suppressing" or "suppressing" used herein in connection with the proliferation of endometrial tissue means that mitotic proliferation of endometrial tissue is suppressed by administration of a progesterone antagonist relative to untreated endometrial tissue under identical conditions and should be distinguished from cell death via, e.g., apoptosis. The activity of progesterone antagonists in suppressing endometrial mitotic proliferation can be tested, e.g., in a uterine cell line by, e.g., comparing bromodeoxyuridine (BrdU) incorporation in progesterone antagonist-treated cells to control (untreated) cells.

[0018] The term "not significantly reduced" as used herein in connection with female hormone levels means that hormone levels are maintained within the normal range during administration of the compositions of the invention. Thus, it is believed that some reduction in hormone levels may occur as long as hormone levels are maintained within the normal range.

[0019] The term "not significantly increased" as used herein in connection with female hormone levels means that hormone levels are maintained within the normal range during administration of the compositions of the invention. Thus, it is believed that some increase in hormone levels can occur as long as hormone levels are maintained within the normal range.

[0020] The subject description relates to the use of progesterone antagonists in doses effective for suppression of endometrial proliferation. The procedures arise from the unexpected finding that certain progesterone antagonists exert an inverse, dose-dependent effect on endometrial proliferation while maintaining estrogen levels within the normal range. Specifically, chronic high-dose administration of the antiprogestin/SPRM CDB-4124 was found to suppress endometrial proliferation while lower doses failed to suppress endometrial proliferation and even tended to stimulate endometrial proliferation, despite similar estrogen levels observed at high and low doses. This is particularly surprising in view of the inability of antiprogestin/SPRM RU 486 to suppress endometrial proliferation at a high dose, as shown below, and several recent reports that chronic high-dose antiprogestin administration stimulates endometrial proliferation, possibly due to the effects of unopposed estrogen. The subject description also shows that progesterone antagonists are unexpectedly useful in the treatment of pain associated with endometriosis.

[0021] The suppression of endometrial proliferation during a treatment regimen comprising daily administration of an effective amount of a progesterone antagonist over a period of six months, described below, demonstrates the benefit of such progesterone antagonists where chronic/long-term administration is desired. Accordingly, the invention relates to certain progesterone antagonists for use in treatment for suppressing endometrial proliferation during administration periods 1 to 6

[0022] The subject description relates to the use of progesterone antagonists in doses effective for suppression of endometrial proliferation. The procedures arise from the unexpected finding that certain progesterone antagonists exert an inverse dose-dependent effect on endometrial proliferation while maintaining estrogen levels within the normal range. Specifically, chronic high-dose administration of the antiprogestin/SPRM CDB-4124 was found to suppress endometrial proliferation, while lower doses failed to suppress endometrial proliferation and even tended to stimulate endometrial proliferation, despite similar estrogen levels observed at high and low doses. This is particularly surprising in view of the inability of the antiprogestin/SPRM RU 486 to suppress endometrial proliferation at a high dose, shown below, and several recent reports that chronic high-dose antiprogestin administration stimulates endometrial proliferation, possibly due to the effects of unopposed estrogen. The subject description also shows that progesterone antagonists are unexpectedly useful in the treatment of pain associated with endometriosis.

[0023] Suppression of endometrial proliferation during a treatment regimen comprising daily administration of an effective amount of a progesterone antagonist over a period of six months, described below, demonstrates the benefit of such progesterone antagonists where chronic/long-term administration is desired. In this sense, the invention relates to certain progesterone antagonists for use in treatment for the suppression of endometrial proliferation. During the application period, the composition may be applied daily or periodically such as every other day. The composition is applied intermittently. For example, the composition may be administered for an administration period of 1, 2, 3, 4, 5, or six months, followed by a break period, followed by an administration period of 1, 2, 3, 4, 5, or six months, and so on.

[0024] "Intermittent administration" means a period of administration of a therapeutically effective dose of a progesterone antagonist, followed by a period of interruption, followed by another administration period, and so on.

[0025] The composition was administered intermittently so that the subject menstruated during at least one break period. This approach is expected to avoid adverse effects associated with thickened or stagnant endometrium that may accompany prolonged treatment with progesterone antagonists, such as spotting, breakthrough bleeding, endometrial hyperproliferation, or endometrial cancer. At least one, and preferably each, period of interruption is of sufficient length for the subject to menstruate. More preferably, the subject menstruates during each withdrawal period. In a particularly preferred embodiment, the composition is administered daily for a four-month application period, followed by a break period during which the subject menstruates, followed by another four-month application period, and so on.

[0026] Optionally, a gonadotropin-releasing hormone (GnRH) agonist or antagonist may be administered during the withdrawal period to accelerate endometrial shedding and renewal. Non-limiting examples of GnRH agonists include nafarelin, buserelin, leuprorelin, triptorelin, goserelin, [DLys<6>]GnRH, effective for the treatment of pain associated with endometriosis. For example, administration of progesterone antagonists can reduce pain associated with endometrial lesions. Pain is the most common and debilitating symptom of endometriosis and is the primary indication for both medical and surgical treatment of the disease. Pain can be manifested as dysmenorrhoeal pain, pelvic pain, lower back pain, abdominal pain, breast pain, dyspareunia, and the like. Administration of progesterone antagonists may also reduce the size of endometrial lesions. Current regimens for the treatment of endometriosis include GnRH agonists that induce pseudomenopause by inhibiting ovarian estrogen secretion and are therefore not useful for long-term use due to loss of bone density, loss of total body calcium, and other osteoporosis-like side effects. The compositions according to the invention can be administered long-term without a significant decrease in estrogen levels.

[0027] In a further exemplary embodiment, the present invention provides methods for treating an estrogen-dependent condition associated with current hormonal therapies using estrogenic compounds such as estrogens or SERMS by administering a co-administered amount of a progesterone antagonist effective to suppress endometrial proliferation. Estrogen-dependent conditions associated with current estrogen/SERM hormone therapies include, but are not limited to, endometrial hyperplasia and endometrial cancer. In this regard, a progesterone antagonist can be administered before, during, or after estrogen or SERMS as part of a regimen of combined hormone therapy.

[0028] In the following exemplary embodiment, the subject description provides a hormone replacement procedure comprising administering to a menopausal or post-menopausal woman an effective amount of a progesterone antagonist and an estrogen compound, wherein the amount of progesterone agonist is effective for suppressing an estrogen-dependent condition. The estrogenic compound can be an estrogen or a SERM. The estrogen compound may be administered before, after, or may be co-administered with a progesterone antagonist. An estrogen-dependent condition may be, without limitation, endometrial proliferation, endometrial hyperproliferation, or endometrial cancer.

[0029] In a preferred embodiment of each method of the description, administration of a progesterone antagonist to a woman does not significantly reduce estrogen levels in the woman. Thus, the present disclosure provides an advantage over current therapies for the treatment of endometriosis that often use gonadotropin-releasing hormone (GnRH) agonists such as Lupron® (leuprolide acetate).

[0030] In the next preferred embodiment of each method of the description, administration of a progesterone antagonist to a woman does not significantly increase progesterone levels in the woman. More preferably, administration of the progesterone antagonist to the female reduces progesterone levels in the female, particularly luteal phase progesterone levels.

[0031] In the next preferred embodiment of each method of the description, the progesterone antagonist exhibits reduced affinity for the glucocorticoid receptor. More preferably, the binding affinity of the progesterone antagonist for the progesterone receptor is at least 1.5 times greater than the binding affinity of the progesterone antagonist for the glucocorticoid receptor. A useful progesterone antagonist includes CDB-4124 (21-methoxy-17α-acetoxy-11β-(4N,N-dimethylaminophenyl)-19-norpregna-4,9-dien-3,20-dione) with the following structural formula:

[0032] Antiprogestins that may be useful in the invention include CDB-2914 (17αacetoxy-11β-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-dien-3,20-dione).

[0033] In a preferred embodiment, the progesterone antagonist is the antiprogestin/SPRM CDB-4124 (21-methoxy-17α-acetoxy-11β-(4 N,N-dimethylaminophenyl)-19-norpregna-4,9-diene-3,20-dione). Example 10 shows that administration of CDB-4124 at a high dose (50 mg/day) suppresses endometrial proliferation in adult women, but does not suppress endometrial proliferation at lower doses (25 mg/day and 12.5 mg/day).

[0034] The progesterone antagonist compositions of the present invention may be administered to patients undergoing any hormone therapy associated with an increased risk or incidence of endometrial hyperplasia or endometrial cancer. These treatments may include, but are not limited to, the administration of estrogen or the administration of SERMs. The progesterone antagonist compositions of the present invention may also be administered to patients undergoing antiestrogen treatments because the patients may benefit from the antiproliferative effects that the progesterone antagonist compounds exert on endometrial tissue of the uterus.

[0035] SERMs are currently used to treat a variety of disorders including breast cancer, osteoporosis, colon cancer, neurodegenerative diseases such as Parkinson's and Alzheimer's disease, cardiovascular disease, vaginal atrophy and obesity. However, SERM therapy has been associated with endometrial hyperplasia and endometrial cancer. For example, treatment of breast cancer with tamoxifen results in about a 20% incidence of hyperplasia with atypia in women with an intact uterus. Patients with endometrial specimens exhibiting atypia have a 25% probability of progression to carcinoma. The compounds for use in the present invention are administered in doses sufficient to antagonize the hyperplasia accompanying treatment with SERMs. The compounds of the present invention may be administered in combination with SERMs for the treatment of any of the above-mentioned disorders.

[0036] Estrogens are currently administered as part of hormone replacement therapy (HRT) to postmenopausal women who no longer produce estrogen. However, estrogen-only therapy is considered unsafe for menopausal women with an intact uterus because of the accompanying endometrial hyperplasia. Progestin co-administration is often prescribed to antagonize the hyperproliferative effects of estrogen; however, the addition of progestin has been associated with breast cancer in the WHI studies and may result in breakthrough bleeding. The compounds for use in the present invention may be administered in combination with estrogens as part of a hormone replacement regimen.

[0037] The compounds for use as described in the present invention can act as progesterone antagonists in the uterus. The compounds for use in the present invention may be suitable for the prolonged use required in menopausal patients undergoing hormone replacement therapy, as well as for other indications. Where such use is contemplated, the compounds preferably have only low glucocorticoid receptor binding activity and thus, the compounds do not significantly affect glucocorticoid receptor functions. In this way, administration of the compound may have reduced side effects, such as mood swings, fatigue and weight loss, which are typically noted when antiprogestins with a high affinity for the glucocorticoid receptor are used.

[0038] In the following exemplary embodiment, the present invention describes methods that can be used to identify compounds that possess selective progesterone receptor binding activity. These procedures include receptor binding and in vivo biological assays such as anti-McGinty, anti-Clauberg, glucocorticoid, estrogenic, androgenic, anti-glucocorticoid (AG), anti-estrogenic and anti-androgenic activities as well as post-coital and anti-ovulatory activities where the lead compounds of this invention are used as a reference.

[0039] Potential SPRMs can also be analyzed for their effect on transcriptional activity in human cells. When the SPRMs described in this invention are used as a reference, this analysis can provide information on (1) the interaction of the SPRM with the receptor, (2) the interaction of the activated receptor with other transcription factors, (3) the activation of the transcription complex on the progesterone responsive element (PRE); and finally to its effect on gene expression. In these experiments, a plasmid expressing hPR-B can be cotransfected with any reporter known to one skilled in the art under a PRE-dependent promoter in HeLa, HepG2 or T47D cells. Reporters can include, but are not limited to, luciferase, beta-galactosidase, green fluorescent protein, red fluorescent protein, or yellow fluorescent protein. After transfection, cells were treated with the test compound or one of the SPRMs listed in this application as a positive control. After treatment, cells were analyzed for reporter expression.

[0040] Potential SPRMs can be tested for their ability to antagonize dexamethasone-induced cell death in the human lymphocyte cell line CEM-7 and compared to the effects of the SPRMs mentioned in this specification. In these experiments, dexamethasone can be added at a concentration that results in cell death. The cells were then treated with one of: RU486, one of the SPRMs of the present invention or a test compound at concentrations between 10<-6> and 10<-8>M.

[0041] Progesterone antagonist compounds that can be used in accordance with the present invention can be synthesized using synthetic chemistry techniques known in the art such as those described in US Pat. 6,861,415. It should be understood that certain functional groups may interfere with other reactants or reagents under reaction conditions and may therefore require temporary protection. The use of protecting groups is described in 'Protective Groups in Organic Synthesis', 2nd edition, T. W. Greene & P. G. M. Wutz, Wiley-Interscience (1991).

[0042] In one exemplary embodiment, the compositions for use in the invention contain one or more progesterone antagonists or pharmaceutically acceptable salts thereof. Depending on the conditions of the process, the obtained salt compound can be in neutral or salt form. Salt forms include hydrates and other solvates and also crystalline polymorphs. Both the free base and salts of these end products can be used in accordance with the invention.

[0043] Acidic addition salts can be transformed into a free base in a manner known per se by using basic agents such as alkalis or by means of ion exchange. The resulting free base can also form salts with organic or inorganic acids.

[0044] In the preparation of acid addition salts, such acids are preferably used which form suitable pharmaceutically acceptable salts. Examples of such acids are hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, aliphatic acid, alicyclic carboxylic or sulfonic acids, such as formic acid, acetic acid, propionic acid, succinic acid, glycolic acid, lactic acid, malic acid, tartaric acid, citric acid, ascorbic acid, glucuronic acid, fumaric acid, maleic acid, hydroxymaleic acid, pyruvic xylene, aspartic acid, glutamic acid, p-hydroxybenzoic acid, embonic acid, ethanesulfonic acid, hydroxyethanesulfonic acid, phenylacetic acid, mandelic acid, halobenzenesulfonic acid, toluenesulfonic acid, galactaric acid, galacturonic acid or naphthalenesulfonic acid. All polymorphs of the crystalline form can be used in accordance with the invention.

[0045] Base addition salts may also be used in accordance with the invention and may be prepared by contacting the free acid form with a sufficient amount of the desired base to produce the salt in a conventional manner. The free acid form can be regenerated by contacting the salt form with an acid and isolating the free acid in a conventional manner. Pharmaceutically acceptable base addition salts are formed with metals or amines, such as alkali and alkaline earth metals or organic amines. Examples of metals used as cations are sodium, potassium, calcium, magnesium and the like. Examples of suitable amines are amino acids such as lysine, choline, diethanolamine, ethylenediamine and N-methylglucamine.

[0046] For the above purposes, the compounds of the present invention can be administered to the patient by any conventional route where the progesterone antagonist is active. For example, the progesterone antagonist of the present invention can be administered orally, parenterally, sublingually, transdermally, rectally, transmucosally, topically, via inhalation, via buccal administration, or combinations thereof. Parenteral administration includes, but is not limited to, intravenous, intraarterial, intraperitoneal, subcutaneous, intramuscular, intrathecal, intraarticular, intracisternal, and intraventricular. The form of administration can be a tablet, capsule, pill, nasal mist, aerosol, pellet and implant (or other depot).

[0047] The therapeutically effective amount of the composition required for use in therapy may vary depending on the particular compound used, the route of administration, the severity of the condition being treated, the length of time during which the activity is desired, among other factors, and is ultimately determined by the physician in charge. In all cases, the effective dose of a particular compound is that which is sufficient to suppress endometrial proliferation. However, in general, doses used for human treatment are typically in the range of about 0.001 mg/kg to about 500 mg/kg per day, for example about 1 µg/kg to about 1 mg/kg per day or about 1 µg/kg to about 100 µg/kg per day. For most large mammals, the total daily dose is from about 1 to 100 mg, preferably from about 2 to 80 mg. The dosage regimen can be adjusted to provide an optimal therapeutic response. The desired dose may conveniently be administered in a single dose or as multiple doses administered at appropriate intervals, for example as two, three, four or more sub-doses per day.

[0048] Illustratively, a composition according to the invention can be administered to a subject to provide the subject with a progesterone antagonist in an amount of about 1 µg/kg to about 1 mg/kg of body weight, for example about 1 µg/kg, about 25 µg/kg, about 50 µg/kg, about 75 µg/kg, about 100 µg/kg, about 125 µg/kg, about 150 µg/kg, about 175 µg/kg, around 200 µg/kg, around 225 µg/kg, around 250 µg/kg, around 275 µg/kg, around 300 µg/kg, around 325 µg/kg, around 350 µg/kg, around 375 µg/kg, around 400 µg/kg, around 425 µg/kg, around 450 µg/kg, about 475 µg/kg, about 500 µg/kg, about 525 µg/kg, about 550 µg/kg, about 575 µg/kg, about 600 µg/kg, about 625 µg/kg, about 650 µg/kg, about 675 µg/kg, about 700 µg/kg, about 725 µg/kg, about 750 µg/kg, about 775 µg/kg, about 800 µg/kg, about 825 µg/kg, about 850 µg/kg, about 875 µg/kg, about 900 µg/kg, about 925 µg/kg, about 950 µg/kg, about 975 µg/kg or about 1 mg/kg body weight.

[0049] Compositions for use in the present invention may contain from about 25 to about 90% of the active ingredient in combination with a carrier, typically between about 5% and 60% by weight.

[0050] Solid carriers can include starch, lactose, dicalcium phosphate, microcrystalline cellulose, sucrose and kaolin, while liquid carriers can include sterile water, polyethylene glycols, nonionic surfactants and edible oils such as corn, peanut and sesame oils, as appropriate for the nature of the active ingredient and the specific desired form of application. Flavoring agents, coloring agents, preservatives and antioxidants, for example, vitamin E and ascorbic acid, may also be included in the preparations. Under normal conditions of storage and use, preparations may contain a preservative to prevent the growth of microorganisms.

[0051] The compositions for use in the present invention may be formulated into tablets in a tablet press using techniques well known to those skilled in the relevant art. Optionally, the active ingredients according to the invention can also be compressed separately into bilayer tablets. The pills may contain anti-estrogens, estrogens or SERMs as one of the active agents. The compositions of the present invention may also be formulated as an oily solution.

[0052] Patients undergoing treatments with the compositions of the present invention should be routinely monitored for their serum estrogen and glucocorticoid levels.

[0053] The following non-limiting examples are provided to assist in understanding the description of the present invention.

Example 1. Formulations of the present invention may be prepared as tablets.

[0054] To obtain tablets for carrying out the present invention, the following ingredients may be pressed together in a tablet press:

50.0 mg of CBD-4124

140.5 mg lactose

69.5 mg Cornstarch

2.5 mg of poly-N-vinylpyrrolidone

2.0 mg of aerosil

0.5 mg Magnesium stearate

[0055] To obtain bilayer tablets for carrying out the present invention, the following ingredients may be pressed together in a tablet press:

20.0 mg tamoxifen

50.0 mg of CBD-4124

105.0 mg Lactose

40.0 mg Cornstarch

2.5 mg of poly-N-vinylpyrrolidone 25

2.0 mg of aerosil

0.5 mg Magnesium stearate

[0056] To obtain tablets containing antiestrogens for carrying out the present invention, for example, the following ingredients can be pressed together in a tablet press:

10.0 mg Raloxifene

50.0 mg of CBD-4124

125.0 mg Lactose

50.0 mg Cornstarch

2.5 mg of poly-N-vinylpyrrolidone 25

2.0 mg of aerosil

0.5 mg Magnesium stearate

[0057] In order to obtain oily preparations for carrying out this invention, for example the following ingredients can be mixed together and poured into ampoules:

100.0 mg of CBD-4124

343.4 mg Castor oil

608.6 mg Benzyl benzoate

Example 2. Compounds of the present invention may have only weak antiglucocorticoid receptor binding activity.

[0058] Certain antiprogestins were tested in receptor binding assays for their ability to bind rabbit progesterone receptor (rbPR) and glucocorticoid receptor (rbGR). Briefly, cytosol containing PR or GR were prepared in TEGMD buffer (10 mM Tris, pH 7.2, 1.5 mM EDTA, 0.2 mM sodium molybdate, 10% glycerol, 1 mM DTT) from uterus or thymus, respectively, of estradiol-primed immature rabbits. For PR binding, cytosol was incubated with 6 nM 1,2-[<3>H]progesterone (50.0 Ci/mmol) and competitors were added at concentrations from 2 to 100 nM. For GR binding, cytosol was incubated with 6 nM 6,7-[<3>H]-dexamethasone (40 Ci/mmol) and test compounds were added at concentrations from 20 to 100 nM. After overnight incubation at 4°C, bound and unbound [<3>H] steroids were separated by addition of dextran-coated charcoal and centrifugation at 2100 x g for 15 min at 4°C. Supernatants containing [ 3 H]-steroid receptor complexes were poured into vials containing 4 ml Optifluor (Packard Instrument Co.), vortexed, equilibrated in a liquid scintillation counter for 30 min and then counted for 2 min. The EC50 (effective concentration) for each standard curve and each of the compound curves was determined by entering the count data into a four-parameter sigmoid computer program (RiaSmart® Immunoassay Data Reduction Program, Packard Instrument Co., Meriden, Conn.). The relative binding affinity (RBA) for each compound was calculated using the following equation: EC50 of standard/EC50 of test compound x 100. Standards for PR and GR assays were unlabeled progesterone and dexamethasone, respectively. The results of these experiments are summarized in Table 1, as the ratio of the relative binding affinities of each compound to the rbPR and rbGR receptors (rbPR/rbGR). This differential reflects the relative activity of the compound in the cell or tissue that possesses the two receptors and the required transcriptional cofactors.

[0059] Table 1 also gives the relative biological activities of the same compounds in rabbit uterus by anti-McGinty and anti-Clauberg assays. The compound CDB-2914 (listed at the end of the Table) was used as a control or reference compound (rabbit biological activity = 1.00) for these experiments because the results of experiments using CDB-2914 have been published previously (Hild-Petito et al., 1996; Passaro et al., 1997; Reel et al., 1998; Larner et al., 2000). For the anti-McGinty test, immature female rabbits received a subcutaneous injection of 5 µg of estradiol in 10% ethanol/sesame oil every day for 6 consecutive days. On day 7, animals underwent sterile abdominal surgery to ligate a 3-4 cm segment of both uterine horns. The test compound in the appropriate solvent was injected intraluminally into the ligated segment of one uterine horn and the vehicle alone into the other horn. A stimulating dose of progesterone (267 µg/day) was administered subcutaneously to each rabbit every day for the next three days to induce endometrial proliferation. All animals were sacrificed on day 10 for hysterectomy where the central segment was removed by ligatures and fixed in 10% neutral buffered formalin and subjected to histological processing. Five-micron sections stained with hematoxylin and cosine were evaluated microscopically for the degree of endometrial glandular proliferation. The percentage inhibition of endometrial proliferation for each rabbit was calculated and the mean value of the group of five animals was recorded. For the Anti-Clauberg test, immature female rabbits received a subcutaneous injection of 5 µg of estradiol in 10% ethanol/sesame oil every day for 6 consecutive days. On day 7, animals received progesterone by subcutaneous injection (160 µg/day) and the experimental compound in the appropriate vehicle orally or subcutaneously for five consecutive days. One group of rabbits received only progesterone. Twenty-four hours after the last dose, all animals were sacrificed to remove the uterus, which was cleared of all fat and connective tissue, weighed to the nearest 0.2 mg, and placed in 10% neutral buffered formalin for subsequent histological processing. Five-micron sections stained with hematoxylin and eosin were evaluated microscopically for the degree of endometrial glandular proliferation. Percent inhibition of endometrial proliferation at each test compound dose level was performed by comparison with progesterone-stimulated animals alone. The data presented in Table 1 (rabbit biol. act.) reflect the average results obtained for each compound using the anti-McGinty and anti-Clauberg assays against CDB-2914.

[0060] Antiprogestins tested were ranked based on the selectivity of each compound for rabbit PR versus rabbit GR, as listed in Table 1. Antiprogestins were also ranked based on biological activity in the rabbit uterus. The data presented in Table 1 show that the affinity of the lead compounds for the progesterone receptor was at least 1.5 times greater than their affinity for the glucocorticoid receptor.

[0061] The results of these studies also show that the two lead compounds CDB-4124 and CDB-4059 have potent antiprogestin activity in the rabbit uterus compared to RU 486 and CDB-2914. Both compounds have no estrogenic, androgenic, anti-estrogenic and anti-androgenic activities. Both compounds possess minimal activity against the anti-glucocorticoid receptor, a feature that distinguishes them from RU 486 and CDB-2914 which are moderately active in binding the glucocorticoid receptor. In these analyses, CDB-4124 performed slightly better than CDB-4059

TABLE 1. RECEPTOR BINDING AND BIOLOGICAL ACTIVITIES OF SPRMS

SPRM rbPR/rbGR rabbit biol. SPRM rbPR/rbGR Rabbit biol.

active active

4239 14.80 0.60 4416 1.33 0.77

4241 9.10 0.34 4417 1.31 0.70

4361 7.20 3.03 4111 1.30 0.36

4306 5.90 0.95 4125 1.19 1.55

4363 5.75 2.53 4223 1.17 Not given

3875 5.11 1.40 4398 1.16 0.99

4362 4.74 1.25 4058 1.08 0.90

4352 4.21 0.57 4418 1.03 0.25

4176 3.83 0.20 4177 1.03 0.00

4243 2.90 0.00 4030 0.96 0.30

4119 2.60 0.10 4374 0.95 2.25

4324 2.16 1.10 4399 0.93 0.35

4247 2.06 1.70 4152 0.82 1.40

4205 1.99 1.00 4110 0.70 0.10

4059 1.89 2.90 4031 0.69 0.70

4400 1.76 2.29 4101 0.61 0.65

3247 1.74 0.10 4248 0.42 0.00

4167 1.69 1.50 4227 0.38 0.00

4124 1.58 3.60 4393 0.35 0.00

4226 1.51 0.54 4396 0.18 Not given

4206 1.44 0.68 2914 1.07 1.00

Example 3. Measurement of cortisol.

[0062] Several different experimental systems support the conclusion that RU 486 increases cortisol because RU 486 has potent anti-glucocorticoid properties in humans and primates.

[0063] However, as shown in Figure 1, rats treated with RU 486 at 10 mg/kg showed no significant difference in cortisol levels. In contrast, rats treated with CDB-4124 or CDB-4059 at the same dose levels had significantly higher serum cortisol levels than control rats.

[0064] These higher levels were in the range of 3-4 ug/dl (30-40 ng/ml). The effects were dose-dependent in that increasing doses of CDB-4124 led to increased cortisol (Figure 2).

[0065] This difference in the effects of RU 486 versus CDB-4124 or CDB-4059 on cortisol levels can be explained by the assumption that after 21 days of chronic dosing, the rat liver was able to metabolize RU 486 better than either of the two CDB compounds.

Example 4. Measurement of corticosterone.

[0066] Corticosterone is the most abundant glucocorticoid in rats. The effects of SPRMs on cortisol shown in Figures 1 and 2 may be secondary to strong effects on corticosterone. To better investigate this phenomenon, corticosterone levels were measured in groups that showed the greatest changes in cortisol levels, such as groups treated with CDB-4124 at 20 mg/kg or 10 mg/kg. For comparison, the following groups were also analyzed: group receiving 20 mg/kg CDB-4124 plus 10 mg/kg progesterone, group receiving 10 mg/kg CDB-4124 plus 10 mg/kg progesterone, group receiving 10 mg/kg RU 486, group receiving 10 mg/kg progesterone alone, control group. Corticosterone levels were 10-40 times higher than cortisol levels. However, almost no difference was noted between the groups regarding mean corticosterone levels. There were no differences between groups before treatment (p = 0.43, Kruskal-Wallis test), after 21 days of treatment (p = 0.57, Kruskal-Wallis test), or after 28 days of treatment and at sacrifice (p = 0.061, Kruskal-Wallis test.

[0067] To measure the effects of exogenous progesterone on serum conticosterone, corticosterone levels were compared in 3 paired groups that differed in whether they received exogenous progesterone (eg, comparisons of control vs. progesterone or CDB-4124 at 20 mg/kg vs. CDB-4124 at 20 mg/kg plus progesterone, or CDB-4124 at 10 mg/kg vs. CDB-4124 at 10 mg/kg plus progesterone). A statistically significant difference was detected: corticosterone levels were decreased in progesterone-treated animals after 21 days of treatment (p = 0.029, Mann-Whitney Wilcoxon test, two-tailed). This effect was not confirmed in sera collected at sacrifice. No differences were found in serum corticosterone between the progesterone and CDB-4124 groups, the progesterone and RU-486 groups, or the RU-486 and CDB-4124 groups.

[0068] The relationship between serum cortisol and serum corticosterone in each group was also investigated. There was a strong positive linear correlation between the two for CDB-4124 at 20 mg/kg (r<2>= 0.78), for CDB-4124 at 10 mg/kg (r<2>= 0.82), and for RU 486 (r<2>= 0.85). Adding progesterone to the first two groups for CDB-4124 made the relationship much weaker (r<2>= 0.34 for group 10 and r<2>= 0.37 for group 11, respectively). Progesterone alone did not show such a positive relationship (r<2>= -1.0). The control group did not show a relationship between the two glucocorticoids (r<2>= 0.064). Thus, the increased cortisol levels in the CDB-4124 groups correlated with corticosterone levels, possibly as a consequence of the conversion from corticosterone being somewhat enhanced. This is consistent with the effect of CDB-4124 noted above: an effect on the metabolic enzymes responsible for progesterone and cortisol levels.

[0069] Although no potent effect of CDB-4124 was found on the primary glucocorticoid in rats, nevertheless, for safety reasons, patients receiving CDB-4124 or CDB-4059 in phase I clinical trials should be monitored for possible antiglucocorticoid effects including possible increases in serum cortisol, corticosterone or ACTH.

Example 5. Testing the anti-proliferative effects of SPRMs in uterine cells.

[0070] Any uterine cell lines can be used. Proliferation was measured in 96-well microtiter plates. 5X10<3> cells were added to each chamber. Culture medium and drug solutions were added to Perkin Elmer Cetus PRO/PETTE chambers. The culture medium was IMEM supplemented with 5% fetal calf serum. Eight drug concentrations were tested, in duplicate, from 0.078 µM to 10 µM. The samples include tamoxifen alone and each of the compounds described in this specification in combination with tamoxifen.

[0071] After incubation for four days, the medium was replaced with fresh medium containing the drug, and after a total of seven days, the cell monolayers were fixed with trichloroacetic acid and stained with sulforhodamine dye. The absorbances (492 nm) of the extracted dye solutions were measured with a Titertek Multiscan plate reader. Dose-response curves (percentage of control absorbances versus drug concentrations) were constructed to estimate IC50 values defined as drug concentrations (micromolar) that inhibited 50% of proliferation. IC50 values are correlated with the potency of the tested drug in inhibiting cell proliferation and therefore provide the information needed to identify compounds suitable for preventing hyperproliferation of uterine cells.

Example 6. CDB-4124 lowers luteal phase progesterone in macaque monkeys

[0072] Macaque monkeys (Macaca fascicularis) (n=14) were treated orally for 36 weeks with CDB-4124 or RU-486 at 1.0 mg/kg/day or with placebo (control). The next group (n=14) received Lupron® IM once a month. Urinary progesterone levels were measured for each animal one month during the middle of the study (weeks 14-17) and during the last month of the study (weeks 33-36). The results are presented below:

Example 7. CDB-4124 does not lower follicular-phase estrogen in macaque monkeys

[0073] Urinary estrogen levels were measured for each animal from Example 6 for one month during the middle of the study (weeks 14-17) and during the last month of the study (weeks 33-36). Follicular phase results are based on 35 baseline ovulatory cycles. The results are presented below:

Example 8. CDB-4124 and Lupron®, but not RU 486, suppress proliferation in macaque monkey endometrial epithelium.

[0074] At week 36, three animals from each group of Example 6 were injected within 24 hours of sacrifice with the thymidine analog, bromodeoxyuridine (BrdU), a marker of proliferating cells and their progeny, to assess tissue proliferation. Full-thickness uterine sections were stained and examined microscopically for evidence of proliferation by % cells positive for BrdU incorporation:

Example 9. CDB-4124 and RU 486, but not Lupron®, Enhance Apoptosis in Macaque Monkey Endometrial Epithelia

[0075] Apoptosis was assessed in tissue from the same animals on plates using the deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) technique. The percentage of apoptotic cells is presented below:

Example 10. CDB-4124 suppresses proliferation in human endometrial epithelium in a dose-dependent manner

[0076] Thirty-nine pre-menopausal adult women diagnosed with endometriosis underwent a six-month study of Proellex™ (CDB-4124) in the treatment of endometriosis. The study included three dose levels of CDB-4124 and a positive control arm. The positive control was Lucrin®, a GnRH agonist commonly used to treat endometriosis (also known as Lupron®). CDB-4124 was administered in a double-blind fashion as a daily oral capsule at doses of 12.5 mg/day (n=2), 25 mg/day (n=3), and 50 mg/day (n=3). The next group (n=4) was injected with a slow-release formulation of Lucrin® once a month as a positive control.

[0077] All doses of CDB-4124, as well as the Lucrin® dose, on average reduced pain-related stress over a six-month exposure to the drug, with the 50 mg CDB-4124 dose reducing pain duration and intensity more effectively than the 12.5 mg or 25 mg doses and significantly superior (p = 0.0012) to Lucrin® in reducing the number of pain days during the study. Pain reduction also occurred faster than with the active control, Lucrin®. Pain response to treatment in this study was analyzed in two ways. Patients in the study kept daily pain diaries to record the severity and frequency of pain. In addition, at each office visit, patients completed endometriosis symptom questionnaires that included a questionnaire that rated pain intensity on a bad day on a scale of 0-10, with 10 being the most intense. Daily pain diaries showed that, on average, women on Lucrin® experienced 19.4 days of pain during the first three months. Women on 50 mg of CDB-4124 experienced less than 1 day of pain during the same period. Women on 25 mg and 12.5 mg of CDB-4124 experienced more days of pain than those reported by women receiving the highest dose of CDB-4124 or Lucrin®. There appeared to be a dose-dependent effect on pain reduction. During the 180-day treatment period, pain diaries showed that women on the 50 mg CDB-4124 dose had 170 or 96% pain-free days (standard deviation = 8.86 days). This reduction in pain duration was significantly better (p=0.0012) than the 117.8 (74%; standard deviation 51.4 days) pain-free days with Lucrin®. The 50 mg dose of CDB-4124 was also statistically superior to both doses, 25 mg and 12.5 mg in terms of pain-free days. Patients on CDB-4124 doses of 12.5 mg and 25 mg had 115.9 (66%; standard deviation 69.2 days) and 133.6 (75%; standard deviation 27.4 days) pain-free days, respectively. These results clearly support a dose response for CDB-4124. The 25 mg and 12.5 mg doses of CDB-4124 were not statistically different from Lucrin®. At the end of the first month of therapy, there was a statistically significant reduction in pain days in the 50 mg Proellex group (p=0.031) compared to baseline, but not in the three other treatment groups. Pain intensity was assessed by asking: "On a scale of 1-10, where 0 means no pain and 10 means extreme pain, how intense is your pain on a bad day?" Mean scores for pain intensity at baseline were 6.3 for the CDB-4124 group and 6.1 for the Lucrin® group. Statistically significant pain relief was evident by the first month in the 25 mg and 50 mg Proellex groups. At month three, all four active treatment groups had a statistically significant reduction in pain compared to baseline, with the following scores: 3.7 (p = 0.03) for 12.5 mg CDB-4124, 3.2 (p = 0.03) for 25 mg CDB-4124, 1.6 (p = 0.015) for 50 mg CDB-4124, and 1.5 (p = 0.015) for 50 mg CDB-4124. (p = 0.016) for Lucrin®. These dose-related reductions continued to month six when the values for pain intensity were 2.0 (p = 0.008), 2.8 (p = 0.023), 0.6 (p = 0.004), and 0.7 (p = 0.016), respectively. Two months after stopping treatment, the pain returned and was of similar intensity in all four treatment groups.

[0078] Women receiving Lucrin® in the study, on average, experienced a reduction in estrogen to post-menopausal levels (<20 pg/ml) by the third month and this was maintained through the sixth month of treatment. This outcome was associated with a statistically significant increase (p = 0.023) in bone resorption biomarkers compared to baseline during the third month, and thus an increased risk of bone loss. During the sixth month as well as the one-month follow-up visit, this increase in bone resorption markers was still present in women treated with Lucrin®. All doses of CDB-4124 maintained estrogen concentrations significantly above those seen with Lucrin® and remained in the low normal range (mean > 40 pg/ml). Notably, there were no significant changes in bone resorption biomarkers in either of the CDB-4124 dose arms at three and six months of treatment. It has been shown that women with post-menopausal estrogen levels were at greater risk of bone loss and other medical conditions. Lucrin® is therefore not indicated for treatment lasting longer than six months.

[0079] Side effects of CDB-4124 were generally mild with no single organ system involved systemically. Although this was a small study and no definitive conclusions can be drawn from the safety data, no safety signals were noted.

[0080] The women in the study were closely monitored for changes in endometrial structure. Data from these trials suggest an inverse, dose-dependent effect of CDB-4124 on endometrial thickness over a three-month period. Comparisons were made with both baseline and ultrasound measurements of endometrial thickness at visit one. After three months on treatment, none of the women receiving the 50 mg dose of CDB-4124 (n=3) exhibited endometrial thickening and in fact exhibited a trend toward a reduction in endometrial thickness compared to baseline. One woman receiving a 25 mg dose of CDB-4124 (n=4) and two women receiving a 12.5 mg dose of CDB-4124 (n=4) exhibited thickened endometrium. Five women receiving Lucrin® did not have endometrial thickening as a consequence of low estrogen status. The results are presented below:

[0081] In two cases where non-menstrual spotting and bleeding were noted in patients with endometrial hyperthickening in the 12.5 mg and 25 mg CDB-4124 groups, a dilation and curettage (D&C) procedure was performed to stop the bleeding. A similar event was not observed at the 50 mg dose during the treatment phase. Greater than normal bleeding occurred in two patients in the 50 mg CDB-4124 group after treatment was stopped and D&C was performed in one group and the other was successfully managed conservatively.

Claims (6)

Patent claims 1. A progesterone antagonist selected from 21-methoxy-17α-acetoxy-11β-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-dien-3,20-dione (CDB-4124) or 17α-acetoxy-11β-(4-N,N-dimethylaminophenyl)-19-norpregna-4,9-diene-3,20-dione for use in medical treating a patient to suppress endometrial proliferation or to prevent hyperproliferation of uterine cells while avoiding adverse effects associated with stagnant or thickened endometrium, according to an intermittent administration regimen comprising administration of a therapeutically effective amount of a progesterone antagonist during an administration period during which the progesterone antagonist is administered every day or every other day for a period of 1, 2, 3, 4, 5, or 6 months, then discontinuing said administration during the interruption period by continuous lack of treatment for a period of time sufficient to a woman gets her period, pri where the specified period is less than the number of days during which the progesterone antagonist was previously applied, then the application of a therapeutically effective amount of the progesterone antagonist every day or every other day, for a period of 1, 2, 3, 4, 5 or 6 months, then the interruption of the said application by means of a continuous lack of treatment for a period of time sufficient for the woman to menstruate, and the repetition of this treatment of intermittent application in order to achieve the suppression of endometrial proliferation or the prevention of hyperproliferation of uterine cells. 2. Progesterone antagonist for use according to claim 1, characterized in that the use is the treatment of endometriosis. 3. Progesterone antagonist for use according to claim 1, characterized in that the progesterone antagonist is administered in a dose of about 2 mg per day to about 80 mg per day. 4. Progesterone antagonism for use according to claim 1 or 3 characterized in that the progestin is administered during said at least one withdrawal period to induce menstruation in a female. 5. Progesterone antagonism for use according to claim 4 characterized in that the progestin is selected from the group consisting of: medrogestone, medroxyprogesterone, megestrol, norethindrone, progesterone, hydroxyprogesterone, acetoxypregnenolone, allylestrenol, cyproterone, desogestrel, dimethisterone, ethisterone, ethynodiol diacetate, gestadene and linestrenol. 6. Progesterone antagonism for use according to claim 1, characterized in that the progesterone antagonist is administered daily for a four month administration period, followed by a break period of sufficient duration for the woman to menstruate, followed by a further four month administration period, and so on.