Means and methods for treating cancer

Abstract

The present invention relates to a pharmaceutical composition comprising a compound of formula (I) ##STR00001##
and methods of treating or preventing cell proliferation disorders comprising administering to a subject a therapeutically active amount or a preventive amount of such a compound.

Claims

1. A method of treating or preventing a cell proliferation disorder, said method comprising the step of treating a subject suffering from or being at risk of the cell proliferation disorder with a therapeutically active amount or a preventive amount of a compound formula (I): ##STR00009##

2. The method of claim 1, wherein the cell proliferation disorder is leukemia, glioma, lymphoma, prostate cancer, thyroid cancer, or sarcoma.

3. The method of claim 2, wherein the subject suffering from or being at risk of said disorder is (a) characterized by increased expression and/or activity of at least one isoform of isocitrate dehydrogenase; or (b) heterozygous or homozygous with regard to a mutant form of at least one isoform of isocitrate dehydrogenase.

4. The method of claim 1, wherein the subject suffering from or being at risk of said disorder is heterozygous or homozygous with regard to a mutant form of at least one isoform of isocitrate dehydrogenase and further wherein said mutant form is characterized by one or more of the following: (i) reduced formation of α-ketoglutarate by the encoded isocitrate dehydrogenase as compared to the wild-type isocitrate dehydrogenase; (ii) increased formation of 2-hydroxyglutarate by the encoded isocitrate dehydrogenase as compared to the wild-type isocitrate dehydrogenase; (iii) no increased formation of 2-hydroxyglutarate by the encoded isocitrate dehydrogenase as compared to the wild-type isocitrate dehydrogenase; (iv) aberrant splicing such as absence of exon 7 in the spliced mRNA; (v) a missense mutation affecting R132 in human isocitrate dehydrogenase 1; (vi) a missense mutation affecting R172 in human isocitrate dehydrogenase 2; (vii) a missense mutation affecting R140 in human isocitrate dehydrogenase 2; (viii) a missense mutation affecting R100 in human isocitrate dehydrogenase 1; and (ix) a missense mutation affecting G97 in human isocitrate dehydrogenase 1.

5. The method of claim 1, wherein the compound is of formula (IV) ##STR00010##

Description

(1) The figures show:

(2) FIG. 1: IC50 values for IDH1wt and IDH1mut treated with compound HMS-101 for 72 hours. The compound described herein has an IC50 of 1 μM on IDH1mut cancer cells in vitro, whereas it has a 12 times higher IC50 (12 μM) on IDH1wt cells in vitro as analysed by Alamar blue cell viability assay.

(3) FIG. 2: D-2HG levels from IDH1mut cells treated with compound HMS-101 (drug) or solvent control. The compound described herein has reduced the neomorphic activity of the IDH1mutant enzyme, i.e. the production of 2HG, as evident by dramatically reduced intracellular 2HG levels in IDH1mutant cells treated with compound HMS-101 for 72 hours at 10 μM dose of compound as compared to the control treated cells.

(4) FIG. 3: Colony forming assay of primary human AML cells with and without IDH1 mutation treated with solvent control (DMSO) or compound HMS-101. Human CD34.sup.+ hematopoietic stem and progenitor cells from healthy donors were used as controls. The compound HMS-101 reduced the colony forming potential of primary human AML cells harboring the IDH1 mutation when compared to primary human AML cells with wildtype IDH1 and cells from healthy donors.

(5) FIG. 4: Rate of apoptosis of primary human AML cells with and without IDH1 mutation treated with solvent control (DMSO) or compound HMS-101. Human CD34.sup.+ hematopoietic stem and progenitor cells from healthy donors were used as controls. The compound HMS-101 increased the rate of apoptosis of primary human AML cells harboring the IDH1 mutation significantly more compared to primary human AML cells with wildtype IDH1 and cells from healthy donors.

(6) FIG. 5: Survival of mice treated with HMS-101.

(7) FIG. 6: Ratio of R-2-hydroxyglutarate (R-2HG) to S-2-hydroxyglutarate (S-2HG) in serum from mice treated with HMS-101 or solvent control (PBS) at 9 weeks after treatment. Serum from 3 mice were pooled per indicated measurement (9 mice for PBS, 12 mice for HMS-101).

(8) The following examples illustrate the invention.

EXAMPLE 1

Affinity of Compound with IDH Mutant

(9) The predicted affinity (in silico modeling) of compound HMS-101 to IDH1 is comparable to IDH inhibitor compounds published recently.sup.15 (ΔG≈8 kcal/mol). The compound HMS-101 has significantly better predicted affinity (ΔΔG≈10 kcal/mol) for IDHmut (R132H) in the presence of NADP than to wildtype IDH1. In the absence of NADP, the compound described herein has selectivity towards mutant but not as pronounced as with presence of NADP. This high selectivity is favorable compared to compounds recently patented.sup.16, which show selectivity to the IDH1 mutant by ΔΔG≈1-2 kcal/mol.

EXAMPLE 2

Toxicity Testing in Animals

(10) The compound described herein has been given to mice at a dose of 1 mg intraperitoneally daily for two weeks. The compound was well tolerated by the animals with no visible signs of toxicity.

EXAMPLE 3

In Vitro Proliferation of Cancer Cells (IC50)

(11) The compound described herein has an IC50 of 1 μM on IDH1mut cancer cells in vitro, whereas it has a 12 times higher IC50 (12 μM) on IDH1 wt cells in vitro as analysed by Alamar blue cell viability assay (FIG. 1).

EXAMPLE 4

Neoactivity of IDHmut Enzyme

(12) The compound described herein has reduced the neomorphic activity of the IDH1 mutant enzyme, i.e. the production of 2HG, as evident by dramatically reduced intracellular 2HG levels in IDH1mutant cells treated with compound HMS-101 for 72 hours at 10 μM dose of compound as compared to the control treated cells (FIG. 2).

EXAMPLE 5

Effect of Compound HMS-101 on the Colony Forming Potential of Primary Human Acute Myeloid Leukemia Cells

(13) The compound HMS-101 reduced the colony forming potential of primary human AML cells harboring the IDH1 mutation when compared to primary human AML cells with wildtype IDH1 and cells from healthy donors (FIG. 3).

EXAMPLE 6

Effect of Compound HMS-101 on the Rate of Apoptosis of Primary Human AML Cells

(14) The compound HMS-101 increased the rate of apoptosis of primary human AML cells harboring the IDH1 mutation significantly more compared to primary human AML cells with wildtype IDH1 and cells from healthy donors (FIG. 4).

EXAMPLE 7

In Vivo Effect of HMS-101

(15) HoxA9 immortalized bone marrow cells from C57BL/6J mice were transduced with retroviral vectors expressing IDH1R132C and GFP. One million GFP-expressing sorted cells were injected intravenously in lethally-irradiated syngeneic recipient mice, accompanied by a life-sparing dose of 1×10.sup.5 freshly isolated bone marrow cells from syngeneic mice. One cohort of mice was treated with HMS-101 at a dose of 1 mg/mouse for 5 days/week starting 5 days after transplantation. The control cohort was treated with PBS for 5 days/week starting 5 days after transplantation. The solid line represents the survival of PBS-treated mice, the dotted line represents the survival of HMS-101-treated mice. Follow-up and treatment are ongoing. As all control mice are dead, the graph indicates a survival benefit for HMS-101 treated mice.

EXAMPLE 8

2-Hydroxyglutarate as Marker for Leukemia

(16) 2-hydroxyglutarate (R-2HG), in particular elevated values thereof, typically measured in terms of the ratio between R- and S-form (R-2HG/S-2HG) is a marker for leukemia in accordance with the present invention. As shown in FIG. 6, treatment with a preferred compound in accordance with the present invention (HMS-101) causes a decrease of the ratio R-2HG/S-2HG in treated mice. This establishes both the usefulness of the mentioned ratio as a marker for leukemia and the beneficial effects of HMS-101.