Patent Application
20090281159
The present invention relates to the use of an HDAC inhibitor for the preparation of a medicament for the treatment of myeloma; a method of treating a warm-blooded animal, especially a human, having lymphoproliferative diseases, comprising administering to said animal a therapeutically effective amount of an HDAC inhibitor, especially a compound of formula (I) as defined herein; and to a pharmaceutical composition and a commercial package comprising said combination.
The term “lymphoproliferative diseases”, as used herein, relates lymphoproliferative diseases, such as lymphomas especially primary cutaneous T-cell lymphomas (CTCL). Primary CTCL represent a heterogeneous group of non-Hodgkin-lymphomas (NHL) whose etiology. After the group of primary gastrointestinal lymphomas, CTCL together with the primary cutaneous B-cell lymphomas form the second most common group of extra-nodal NHL.
The compounds of formula (I), as defined herein, are histone deacetylase inhibitors (HDAC inhibitors). Reversible acetylation of histones is a major regulator of gene expression that acts by altering accessibility of transcription factors to DNA. In normal cells, histone deacetylase (HDA) and histone acetyltransferase together control the level of acetylation of histones to maintain a balance. Inhibition of HDA results in the accumulation of hyperacetylated histones, which results in a variety of cellular responses.
Surprisingly, it was now found that HDAC inhibitors, especially the compounds of formula (I), as defined herein, directly inhibit the proliferation of lymphoproliferative diseases, such as CTCL.
Hence, the invention relates to the use of an HDAC inhibitor for the preparation of a medicament for the treatment of lymphoproliferative diseases.
HDAC inhibitor compounds of particular interest for use in the inventive combination are hydroxamate compounds described by the formula (I):
wherein
As appropriate, “unsubstituted” means that there is no substituent or that the only substituents are hydrogen.
Halo substituents are selected from fluoro, chloro, bromo and iodo, preferably fluoro or chloro.
Alkyl substituents include straight- and branched-C1-C6alkyl, unless otherwise noted. Examples of suitable straight- and branched-C1-C6alkyl substituents include methyl, ethyl, n-propyl, 2-propyl, n-butyl, sec-butyl, t-butyl and the like. Unless otherwise noted, the alkyl substituents include both unsubstituted alkyl groups and alkyl groups that are substituted by one or more suitable substituents, including unsaturation, i.e., there are one or more double or triple C—C bonds; acyl; cycloalkyl; halo; oxyalkyl; alkylamino; aminoalkyl; acylamino; and OR15, e.g., alkoxy. Preferred substituents for alkyl groups include halo, hydroxy, alkoxy, oxyalkyl, alkylamino and aminoalkyl.
Cycloalkyl substituents include C3-C9cycloalkyl groups, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and the like, unless otherwise specified. Unless otherwise noted, cycloalkyl substituents include both unsubstituted cycloalkyl groups and cycloalkyl groups that are substituted by one or more suitable substituents, including C1-C6alkyl, halo, hydroxy, aminoalkyl, oxyalkyl, alkylamino and OR15, such as alkoxy. Preferred substituents for cycloalkyl groups include halo, hydroxy, alkoxy, oxyalkyl, alkylamino and aminoalkyl.
The above discussion of alkyl and cycloalkyl substituents also applies to the alkyl portions of other substituents, such as, without limitation, alkoxy, alkyl amines, alkyl ketones, arylalkyl, heteroarylalkyl, alkylsulfonyl and alkyl ester substituents and the like.
Heterocycloalkyl substituents include 3- to 9-membered aliphatic rings, such as 4- to 7-membered aliphatic rings, containing from 1-3 heteroatoms selected from nitrogen, sulfur, oxygen. Examples of suitable heterocycloalkyl substituents include pyrrolidyl, tetrahydrofuryl, tetrahydrothiofuranyl, piperidyl, piperazyl, tetrahydropyranyl, morphilino, 1,3-diazapane, 1,4-diazapane, 1,4-oxazepane and 1,4-oxathiapane. Unless otherwise noted, the rings are unsubstituted or substituted on the carbon atoms by one or more suitable substituents, including C1-C6alkyl; C4-C9cycloalkyl; aryl; heteroaryl; arylalkyl, e.g., benzyl; heteroarylalkyl, e.g., pyridylmethyl; halo; amino; alkyl amino and OR15, e.g., alkoxy. Unless otherwise noted, nitrogen heteroatoms are unsubstituted or substituted by H, C1-C4alkyl; arylalkyl, e.g., benzyl; heteroarylalkyl, e.g., pyridylmethyl; acyl; aminoacyl; alkylsulfonyl; and arylsulfonyl.
Cycloalkylalkyl substituents include compounds of the formula —(CH2)n5-cycloalkyl, wherein n5 is a number from 1-6. Suitable alkylcycloalkyl substituents include cyclopentylmethyl, cyclopentylethyl, cyclohexylmethyl and the like. Such substituents are unsubstituted or substituted in the alkyl portion or in the cycloalkyl portion by a suitable substituent, including those listed above for alkyl and cycloalkyl.
Aryl substituents include unsubstituted phenyl and phenyl substituted by one or more suitable substituents including C1-C6alkyl; cycloalkylalkyl, e.g., cyclopropylmethyl; O(CO)alkyl; oxyalkyl; halo; nitro; amino; alkylamino; aminoalkyl; alkyl ketones; nitrile; carboxyalkyl; alkylsulfonyl; aminosulfonyl; arylsulfonyl and OR15, such as alkoxy. Preferred substituents include including C1-C6alkyl; cycloalkyl, e.g., cyclopropylmethyl; alkoxy; oxyalkyl; halo; nitro; amino; alkylamino; aminoalkyl; alkyl ketones; nitrile; carboxyalkyl; alkylsulfonyl; arylsulfonyl and aminosulfonyl. Examples of suitable aryl groups include C1-C4alkylphenyl, C1-C4alkoxyphenyl, trifluoromethylphenyl, methoxyphenyl, hydroxyethylphenyl, dimethylaminophenyl, aminopropylphenyl, carbethoxyphenyl, methanesulfonylphenyl and tolylsulfonylphenyl.
Aromatic polycycles include naphthyl, and naphthyl substituted by one or more suitable substituents including C1-C6alkyl; alkylcycloalkyl, e.g., cyclopropylmethyl; oxyalkyl; halo; nitro; amino; alkylamino; aminoalkyl; alkyl ketones; nitrile; carboxyalkyl; alkylsulfonyl; arylsulfonyl; aminosulfonyl and OR15, such as alkoxy.
Heteroaryl substituents include compounds with a 5- to 7-membered aromatic ring containing one or more heteroatoms, e.g., from 1-4 heteroatoms, selected from N, O and S. Typical heteroaryl substituents include furyl, thienyl, pyrrole, pyrazole, triazole, thiazole, oxazole, pyridine, pyrimidine, isoxazolyl, pyrazine and the like. Unless otherwise noted, heteroaryl substituents are unsubstituted or substituted on a carbon atom by one or more suitable substituents, including alkyl, the alkyl substituents identified above, and another heteroaryl substituent. Nitrogen atoms are unsubstituted or substituted, e.g., by R13; especially useful N substituents include H, C1-C4alkyl, acyl, aminoacyl and sulfonyl.
Arylalkyl substituents include groups of the formula —(CH2)n5-aryl, —(CH2)n5-1—(CH-aryl)-(CH2)n5-aryl or —(CH2)n5-1CH(aryl)(aryl), wherein aryl and n5 are defined above. Such arylalkyl substituents include benzyl, 2-phenylethyl, 1-phenylethyl, tolyl-3-propyl, 2-phenylpropyl, diphenylmethyl, 2-diphenylethyl, 5,5-dimethyl-3-phenylpentyl and the like. Arylalkyl substituents are unsubstituted or substituted in the alkyl moiety or the aryl moiety or both as described above for alkyl and aryl substituents.
Heteroarylalkyl substituents include groups of the formula —(CH2)n5-heteroaryl, wherein heteroaryl and n5 are defined above and the bridging group is linked to a carbon or a nitrogen of the heteroaryl portion, such as 2-, 3- or 4-pyridylmethyl, imidazolylmethyl, quinolylethyl and pyrrolylbutyl. Heteroaryl substituents are unsubstituted or substituted as discussed above for heteroaryl and alkyl substituents.
Amino acyl substituents include groups of the formula —C(O)—(CH2)n—C(H)(NR13R14)—(CH2)n—R5, wherein n, R13, R14 and R5 are described above. Suitable aminoacyl substituents include natural and non-natural amino acids, such as glycinyl, D-tryptophanyl, L-lysinyl, D- or L-homoserinyl, 4-aminobutyric acyl and ±3-amin-4-hexenoyl.
Non-aromatic polycycle substituents include bicyclic and tricyclic fused ring systems where each ring can be 4- to 9-membered and each ring can contain zerio, one or more double and/or triple bonds. Suitable examples of non-aromatic polycycles include decalin, octahydroindene, perhydrobenzocycloheptene and perhydrobenzo-[f]-azulene. Such substituents are unsubstituted or substituted as described above for cycloalkyl groups.
Mixed aryl and non-aryl polycycle substituents include bicyclic and tricyclic fused ring systems where each ring can be 4- to 9-membered and at least one ring is aromatic. Suitable examples of mixed aryl and non-aryl polycycles include methylenedioxyphenyl, bis-methylenedioxyphenyl, 1,2,3,4-tetrahydronaphthalene, dibenzosuberane, dihydroanthracene and 9H-fluorene. Such substituents are unsubstituted or substituted by nitro or as described above for cycloalkyl groups.
Polyheteroaryl substituents include bicyclic and tricyclic fused ring systems where each ring can independently be 5- or 6-membered and contain one or more heteroatom, e.g., 1, 2, 3 or 4 heteroatoms, chosen from O, N or S such that the fused ring system is aromatic. Suitable examples of polyheteroaryl ring systems include quinoline, isoquinoline, pyridopyrazine, pyrrolopyridine, furopyridine, indole, benzofuran, benzothiofuran, benzindole, benzoxazole, pyrroloquinoline and the like. Unless otherwise noted, polyheteroaryl substituents are unsubstituted or substituted on a carbon atom by one or more suitable substituents, including alkyl, the alkyl substituents identified above and a substituent of the formula —O—(CH2CH═CH(CH3)(CH2))1-3H. Nitrogen atoms are unsubstituted or substituted, e.g., by R13, especially useful N substituents include H, C1-C4alkyl, acyl, aminoacyl and sulfonyl.
Non-aromatic polyheterocyclic substituents include bicyclic and tricyclic fused ring systems where each ring can be 4- to 9-membered, contain one or more heteroatom, e.g., 1, 2, 3 or 4 heteroatoms, chosen from O, N or S and contain zero or one or more C—C double or triple bonds. Suitable examples of non-aromatic polyheterocycles include hexitol, cis-perhydro-cyclohepta[b]pyridinyl, decahydro-benzo[f][1,4]oxazepinyl, 2,8-dioxabicyclo[3.3.0]octane, hexahydro-thieno[3,2-b]thiophene, perhydropyrrolo[3,2-b]pyrrole, perhydronaphthyridine, perhydro-1H-dicyclopenta[b,e]pyran. Unless otherwise noted, non-aromatic polyheterocyclic substituents are unsubstituted or substituted on a carbon atom by one or more substituents, including alkyl and the alkyl substituents identified above. Nitrogen atoms are unsubstituted or substituted, e.g., by R13, especially useful N substituents include H, C1-C4alkyl, acyl, aminoacyl and sulfonyl.
Mixed aryl and non-aryl polyheterocycles substituents include bicyclic and tricyclic fused ring systems where each ring can be 4- to 9-membered, contain one or more heteroatom chosen from O, N or S, and at least one of the rings must be aromatic. Suitable examples of mixed aryl and non-aryl polyheterocycles include 2,3-dihydroindole, 1,2,3,4-tetrahydroquinoline, 5,11-dihydro-10H-dibenz[b,e][1,4]diazepine, 5H-dibenzo[b,e][1,4]diazepine, 1,2-dihydropyrrolo[3,4-b][1,5]benzodiazepine, 1,5-dihydro-pyrido[2,3-b][1,4]diazepin-4-one, 1,2,3,4,6,11-hexahydro-benzo[b]pyrido[2,3-e][1,4]diazepin-5-one. Unless otherwise noted, mixed aryl and non-aryl polyheterocyclic substituents are unsubstituted or substituted on a carbon atom by one or more suitable substituents including —N—OH, ═N—OH, alkyl and the alkyl substituents identified above. Nitrogen atoms are unsubstituted or substituted, e.g., by R13; especially useful N substituents include H, C1-C4alkyl, acyl, aminoacyl and sulfonyl.
Amino substituents include primary, secondary and tertiary amines and in salt form, quaternary amines. Examples of amino substituents include mono- and di-alkylamino, mono- and di-aryl amino, mono- and di-arylalkyl amino, aryl-arylalkylamino, alkyl-arylamino, alkyl-arylalkylamino and the like.
Sulfonyl substituents include alkylsulfonyl and arylsulfonyl, e.g., methane sulfonyl, benzene sulfonyl, tosyl and the like.
Acyl substituents include groups of formula —C(O)—W, —OC(O)—W, —C(O)—O—W or —C(O)NR13R14, where W is R16, H or cycloalkylalkyl.
Acylamino substituents include substituents of the formula —N(R12)C(O)—W, —N(R12)C(O)—O—W and —N(R12)C(O)—NHOH and R12 and W are defined above.
The R2 substituent HON—C(O)—CH═C(R1)-aryl-alkyl- is a group of the formula
Preferences for each of the substituents include the following:
Useful compounds of the formula (I), include those wherein each of R1, X, Y, R3 and R4 is H, including those wherein one of n2 and n3 is 0 and the other is 1, especially those wherein R2 is H or —CH2—CH2—OH.
One suitable genus of hydroxamate compounds are those of formula (Ia):
wherein
Another suitable genus of hydroxamate compounds are those of formula (Ia):
wherein
Another interesting genus is the compounds of formula (Ib):
wherein
Another interesting genus of hydroxamate compounds are the compounds of formula (Ic):
where
Especially useful compounds of formula (Ic), are those wherein R2 is H, or —(CH2)pCH2OH, wherein p is 1-3, especially those wherein R1 is H; such as those wherein R1 is H and X and Y are each H, and wherein q is 1-3 and r is 0 or wherein q is 0 and r is 1-3, especially those wherein Z1 is N—R20. Among these compounds R2 is preferably H or —CH2—CH2—OH and the sum of q and r is preferably 1.
Another interesting genus of hydroxamate compounds are the compounds of formula (Id):
wherein
Especially useful compounds of formula (Id), are those wherein R2 is H or —(CH2)pCH2OH, wherein p is 1-3, especially those wherein R1 is H; such as those wherein R1 is H and X and Y are each H, and wherein q is 1-3 and r is 0 or wherein q is 0 and r is 1-3. Among these compounds R2 is preferably H or —CH2—CH2—OH and the sum of q and r is preferably 1.
The present invention further relates to compounds of the formula (Ie):
or a pharmaceutically acceptable salt thereof. The variable substituents are as defined above.
Especially useful compounds of formula (Ie), are those wherein R18 is H, fluoro, chloro, bromo, a C1-C4alkyl group, a substituted C1-C4alkyl group, a C3-C7cycloalkyl group, unsubstituted phenyl, phenyl substituted in the para position, or a heteroaryl, e.g., pyridyl, ring.
Another group of useful compounds of formula (Ie), are those wherein R2 is H or —(CH2)pCH2OH, wherein p is 1-3, especially those wherein R1 is H; such as those wherein R1 is H and X and Y are each H, and wherein q is 1-3 and r is 0 or wherein q is 0 and r is 1-3. Among these compounds R2 is preferably H or —CH2—CH2—OH and the sum of q and r is preferably 1. Among these compounds p is preferably 1 and R3 and R4 are preferably H.
Another group of useful compounds of formula (Ie), are those wherein R18 is H, methyl, ethyl, t-butyl, trifluoromethyl, cyclohexyl, phenyl, 4-methoxyphenyl, 4-trifluoromethylphenyl, 2-furanyl, 2-thiophenyl, or 2-, 3- or 4-pyridyl wherein the 2-furanyl, 2-thiophenyl and 2-, 3- or 4-pyridyl substituents are unsubstituted or substituted as described above for heteroaryl rings; R2 is H or —(CH2)pCH2OH, wherein p is 1-3; especially those wherein R1 is H and X and Y are each H, and wherein q is 1-3 and r is 0 or wherein q is 0 and r is 1-3. Among these compounds R2 is preferably H or —CH2—CH2—OH and the sum of q and r is preferably 1.
Those compounds of formula (Ie), wherein R20 is H or C1-C6alkyl, especially H, are important members of each of the subgenuses of compounds of formula (Ie) described above.
N-hydroxy-3-[4-[[(2-hydroxyethyl)[2-(1H-indol-3-yl)ethyl]-amino]methyl]phenyl]-2E-2-propenamide, N-hydroxy-3-[4-[[[2-(1H-indol-3-yl)ethyl]-amino]methyl]phenyl]-2E-2-propenamide and N-hydroxy-3-[4-[[[2-(2-methyl-1H-indol-3-yl)-ethyl]-amino]methyl]phenyl]-2E-2-propenamide or a pharmaceutically acceptable salt thereof, are important compounds of formula (Ie).
The present invention further relates to the compounds of the formula (If):
or a pharmaceutically acceptable salt thereof. The variable substituents are as defined above.
Useful compounds of formula (If), are include those wherein R2 is H or —(CH2)pCH2OH, wherein p is 1-3, especially those wherein R1 is H; such as those wherein R1 is H and X and Y are each H, and wherein q is 1-3 and r is 0 or wherein q is 0 and r is 1-3. Among these compounds R2 is preferably H or —CH2—CH2—OH and the sum of q and r is preferably 1.
N-hydroxy-3-[4-[[[2-(benzofur-3-yl)-ethyl]-amino]methyl]phenyl]-2E-2-propenamide or a pharmaceutically acceptable salt thereof, is an important compound of formula (If).
The compounds described above are often used in the form of a pharmaceutically acceptable salt. Pharmaceutically acceptable salts include, when appropriate, pharmaceutically acceptable base addition salts and acid addition salts, e.g., metal salts, such as alkali and alkaline earth metal salts, ammonium salts, organic amine addition salts and amino acid addition salts and sulfonate salts. Acid addition salts include inorganic acid addition salts, such as hydrochloride, sulfate and phosphate; and organic acid addition salts, such as alkyl sulfonate, arylsulfonate, acetate, maleate, fumarate, tartrate, citrate and lactate. Examples of metal salts are alkali metal salts, such as lithium salt, sodium salt and potassium salt; alkaline earth metal salts, such as magnesium salt and calcium salt, aluminum salt and zinc salt. Examples of ammonium salts are ammonium salt and tetramethylammonium salt. Examples of organic amine addition salts are salts with morpholine and piperidine. Examples of amino acid addition salts are salts with glycine, phenylalanine, glutamic acid and lysine. Sulfonate salts include mesylate, tosylate and benzene sulfonic acid salts.
Additional HDAI compounds within the scope of formula (I), and their synthesis, are disclosed in WO 02/22577 published Mar. 21, 2002 which is incorporated herein by reference in its entirety. Two preferred compounds within the scope of WO 02/22577 are:
N-hydroxy-3-[4-[(2-hydroxyethyl){2-(1H-indol-3-yl)ethyl]-amino]methyl]phenyl]-2E-2-propenamide, or a pharmaceutically acceptable salt thereof and
N-hydroxy-3-[4-[[[2-(2-methyl-1H-indol-3-yl)-ethyl]-amino]methyl]phenyl]-2E-2-propenamide, or a pharmaceutically acceptable salt thereof.
The present invention pertains in particular to the use of HDAC inhibitors for the preparation of a medicament for the treatment of myeloma, which is resistant to conventional chemotherapy.
An HDAC inhibitor as used for the present invention displays in the assay described above preferably an IC50 value between 50 and 2500 nM, more preferably between 250 and 2000 nM, and most preferably between 500 and 1250 nM.
Furthermore, the invention relates to a method of treating lymphoproliferative diseases, especially CTCL, comprising administering a therapeutically effective amount of an HDAC inhibitor to a warm-blooded animal, in particular a human, in need thereof, preferably a therapeutically effective amount of a compound of formula (I), as defined above, or the salt of such compound having at least one salt-forming group, to a warm-blooded animal, preferably a human, in heed thereof.
Throughout the present specification and claims lymphoproliferative diseases means preferably CTCL.
The term “treatment”, as used herein, comprises the treatment of patients having lymphoproliferative diseases or being in a pre-stage of said disease which effects the delay of progression of the disease in said patients.
The present invention provides a method of treating lymphoproliferative diseases comprising administering a an HDAC inhibitor in an amount which is therapeutically effective against lymphoproliferative diseases to a warm-blooded animal in need thereof.
The person skilled in the pertinent art is fully enabled to select relevant test models to prove the hereinbefore and hereinafter mentioned beneficial effects on lymphoproliferative diseases of a compound inhibiting the HDAC activity. The pharmacological activity of a compound inhibiting the HDAC activity may, e.g., be demonstrated in a suitable clinical study or by means of the Examples described below. Suitable clinical studies are, e.g., open-label non-randomized, dose escalation studies in patients with advanced myeloma.
The present invention also provides the use of a compound of formula (I), as defined herein, and the use of a COMBINATION OF THE INVENTION for the preparation of a medicament for the treatment of lymphoproliferative diseases.
Adult patients with histologically-confirmed, advanced solid tumors or non-Hodgkin's lymphoma including CTCL whose disease has progressed despite standard therapy or for whom no standard therapy exists, will be enrolled onto arms 1-3.
Patients with advanced-stage CTCL were entered into a Phase I study. All patients had progressed following prior systemic therapy. Patients were entered into the DLT, dose limiting therapy, dose level 30 mg M,W,F cohort (n=1) or the subsequent MTD, maximum tolerated dose, dose level 20 mg M,W,F weekly (n=8). Compound (III) was continued until disease progression or unacceptable toxicity. The first three patients had 3 mm punch biopsies from CTCL-involved skin lesions performed at 0, 4, 8 and 24 hours after administration, which were subjected to gene expression profiling. Microarray analysis was performed using the Affymetrix U133 plus 2.0 GeneChip that has 47,000 probesets and interrogates 38,500 genes.
Results: Nine (9) patients with CTCL have been entered to date. Of the 9 patients evaluable for response, 2 attained a complete response (CR), 2 attained a partial response (PR), 1 achieved stable disease (SD) with ongoing improvement, and 4 progressed on treatment (PD). Of particular interest, 2 patients who were initially SD required discontinuation because of toxicities (Grade III diarrhea at week 4, Grade II fatigue at week 12). Both had ongoing improvement in their disease achieving a CR and PR, respectively 3 months later. Of the 4 responding patients, one with a CR (discontinued after 10 doses due to Grade III diarrhea) progressed at 8 m. Microarray data on the first 3 patients (2 CR and 1 PD) demonstrated distinct gene expression response profiles between the 3 patients. Surprisingly, the patient with PD showed the greatest transcriptional response with more than 16,000 genes activated or repressed over the 24-hour time course. Of these responsive genes, close to 60% were activated while 40% were repressed. In contrast, less than 1,000 genes showed a 2-fold change in expression in the 2 patients with a CR with greater than 85% of the genes being repressed.
Cell lines derived from human CTCL (mycosis fungoides), HUT78, HUT102, HH and MJ were treated with Compound III (LBH589) to assess their sensitivity to the drug. Cells were generally maintained in artificial media, such as Dubelco Modified Eagle Medium (DMEM) or RPMI and supplemented with various levels up to 15% fetal bovine serum. The antibiotics penicillin 100 units/mL) and streptomycin (100 μg/mL) were added to prevent bacterial contamination and maintained at 37° C. and 5% CO2 environment in a sterile incubator.
The MTT is a colorimetric assay to determine the cell proliferation rate. The yellow tetrazolium MTT (3A4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) is reduced by metabolically active cells, in part by the action of dehydrogenase enzymes, to generate reducing equivalents, such as NADH and NADPH. The resulting intracellular purple formazan can be solubilized and quantified by spectrophotometric means. The signals produced is directly proportional to the cell numbers. Describing the MTT assay in detail, experiments were done using 6-point or 9-point drug titrations in multi-well tissue culture dishes, with outer rows left empty. Cells were suspended in complete media at densities of between 103 and 104 cell/mL, respectively, and added per well. The appropriate medium (200 μL) was then added. Twenty-four hours later, 10 μL of MTS solution, were added to one plates to determine the activity at the time of compound addition (T0). This plate was incubated at 37° C. for 4 hours and the optical density was measured on a Molecular Devices Thermomax at 490 nm using the Softmax program. The T0 plate served as a reference for initial activity at the beginning of the experiment.
Compound addition began 24 hours after seeding, the same time as the T0 determination. Serial dilutions at 4-fold, 2-fold, 1-fold, 0.5-fold, 0.25-fold and 0.125-fold of previously determined IC50 values of each compound were made in a 96-deep well plate with the highest concentrations on the edge of the plate. Each of the six dilutions were added in triplicate and complete medium was added to the empty outer rows without cells. The compounds were added to the plates singly or in combination with Compound III (LBH589). The plates were incubated at 37° C. for 72 hours from seeding. The MTS solution was added (as for the T0 plate) and read four hours later. In order to analyze the data, the average value of media alone (background) was subtracted from each experimental well and the triplicate values were averaged for each compound dilution. The following formulas were used to calculate percent growth.
If X>T0, % Growth=100×((X−T0)/(GC−T0))
If X<T0, % Growth=100×(X−T0)/T0)
T0=average value of T0 minus background
GC=average value of untreated cells (in triplicate) minus background
X=average value of compound treated cells (in triplicate) minus background
IC50 the concentration of LBH589 required to inhibit cell growth by 50% and LD50s the concentration required to reduce cell number (kill cells) to 50% the original inoculum were determined. The “% Growth” was plotted against compound concentration and used to calculate IC50s and LD50s, employing the user-defined spline function in Microsoft Excel.
Table 1 shows the antiproliferative effect (IC50) and induction of cell death (LD50) of Compound III (LBH589) in the CTCL cell lines. All four cell lines showed extreme subnanomolar sensitivity (IC50) to the drug, however, only HUT78 and HH were sensitive to LBH589 induced cell death (low nanomolar LD50). It is to be noted that the two cell lines MJ and HUT102 which were insensitive to LBH589 induced death have HTLV infection and this may contribute to their relative insensitivity.
Additionally, Compound III (LBH589) induced the regression of the HH CTCL mouse tumor xenografts in vivo. Mice were implanted with the HH CTCL cell lines and after tumors have grown to 150 mm3, the mice were separated into four groups each containing eight mice. The groups of mice were dosed intravenously with vehicle, 5 mg/kg, 10 mg/kg, or 15 mg/kg daily. The growth of the tumors were followed over 2 weeks and as shown in
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/US07/14985 | 6/26/2007 | WO | 00 | 12/17/2008 |
| Number | Date | Country | |
|---|---|---|---|
| 60806026 | Jun 2006 | US |
