WO2012034942A1

WO2012034942A1 - Compounds for the modulation of aurora kinase b expression

Info

Publication number: WO2012034942A1
Application number: PCT/EP2011/065640
Authority: WO
Inventors: Nathalie UZCÁTEGUI; Anja Høg; Maj Hedtjärn
Original assignee: Santaris Pharma A/S
Priority date: 2010-09-13
Filing date: 2011-09-09
Publication date: 2012-03-22

Abstract

The present invention relates to oligomer compounds (oligomers), which target aurora kinase B mRNA in a cell, leading to reduced expression of aurora kinase B. Reduction of aurora kinase B expression is beneficial for the treatment of certain medical disorders, such as cancer.

Description

COMPOUNDS FOR THE MODULATION OF AURORA KINASE B EXPRESSION FIELD OF INVENTION

The present invention relates to oligomeric compounds (oligomers) that target aurora kinase B mRNA in a cell, leading to reduced expression of aurora kinase B. Reduction of aurora kinase B expression is beneficial for a range of medical disorders, such as cancer.

BACKGROUND

Aurora kinases are a family of serine/threonine kinases that are critical for the establishment of mitotic spindle, centrosome duplication, centrosome separation as well as maturation, chromosomal alignment, spindle assembly checkpoint , and cytokinesis

(Carmena M, Earnshaw WC. The cellular geography of aurora kinases. Nat Rev Mol Cell Biol 2003;4:842-854). These kinases are considered key regulators of mitosis required for an accurate and even distribution of chromosomes between daughter cells. There are three human homologues of Aurora kinases, A, B, and C, which are expressed in different stages of cell cycle (Marumoto T, Zhang D, Saya H. Aurora A— A guardian of poles. Nat Rev Cancer 2005;5:42-50). The roles of the Aurora kinases in cancer has been reviewed; for example, see: Mountzios, G et al (2008) Cancer Treat. Rev. 34: 175-182; Gautschi, O. et al., (2008) Clin. Cancer Res. 14:1639-1648; Kollareddy, M. et al (2008) Biomed. Pap. Med. Fac. Univ. Palacky Olomouc Czech Repub. 152:27-33; Lok, W. et al. (2010) 21 :339-250.

Aurora kinase B (AurkB, serine/threonine kinase 12, STK12) is found to be

overexpressed in a variety of human cancers including colorectal cancer, gliomas, leukemia, lung cancer, pancreatic cancer, prostate cancer and thyroid cancer (Smith SL, Bowers NL, Betticher DC, et al. Overexpression of aurora B kinase (AURKB) in primary non-small cell lung carcinoma is frequent, generally driven from one allele, and correlates with the level of genetic instability. Br J Cancer 2005;93:719-29. Ikezoe T, Yang J, Nishioka C, et al. A novel treatment strategy targeting Aurora kinases in acute myelogenous leukemia. Mol Cancer Ther 2007;6:1851-7. Araki K, Nozaki K, Ueba T, Tatsuka M, Hashimoto N. High expression of Aurora-B/Aurora and Ipll-like midbody-associated protein (AIM-1) in astrocytomas. J Neurooncol 2004;67:53-64. Chieffi P, Cozzolino L, Kisslinger A, et al. Aurora B expression directly correlates with prostate cancer malignancy and influences prostate cell proliferation. Prostate 2006;66:326-33. Sorrentino R, Libertini S, Pallante PL, et al. Aurora B

overexpression associates with the thyroid carcinoma undifferentiated phenotype and is required for thyroid carcinoma cell proliferation. J Clin Endocrinol Metab 2005; 90:928-35). Inhibition of AurkB using small molecules has been tested in vitro and in vivo and several clinical trials are being conducted with small molecules. See Kitzen et al. (2010 Crit. Rev. Oncol. /Hematol. 73:99-110) for a review of Aurora kinase inhibitors. Most of the small molecule inhibitors of the Aurora kinases show activity against two or all three Aurora kinases while a few show specific selectivity for one of the kinases. The small molecule inhibitor AZD1 152 is a highly selective inhibitor of AurkB that shows inhibition of proliferation of several human leukemia cells in vitro (Yang J, Ikezoe T, Nishioka C, et al. AZD1152, a novel and selective aurora B kinase inhibitor, induces growth arrest, apoptosis, and sensitization for tubulin depolymerising agent or topoisomerase II inhibitor in human acute leukemia cells in vitro and in vivo. Blood 2007; 16:2034-40). AZD1 152 also showed growth inhibition of small cell lung cancer cell lines in vitro (Helfrich B, Garcia M, Haney J, Bunn Jr PA. The selective Aurora B kinase inhibitor AZD1152 inhibits in vitro growth in small cell lung cancer (SCLC) cell lines. In: Proceedings EORTC-NCI-AACR 2008 [abstract number 288]) as well as growth inhibition in vivo in xenografts models of human colon, lung, and hematological tumors (Wilkinson RW, Odedra R, Heaton SP, et al. AZD1 152, a selective inhibitor of aurora B kinase, inhibits human tumor xenograft growth by inducing apoptosis. Clin Cancer Res 2007; 12:3682-8). AZD1152 has been in phase I clinical studies showing hints of anti-tumor activity (Schellens JH, Boss D, Witteveen PO, et al. Phase I and pharmacological study of the novel aurora kinase inhibitor AZD1 152. In: ASCO proceedings 2006 [abstract number 3008]). ZM447439 is a small molecule inhibitor with equal activity against Aurora kinase A and B but the phenotypic events that occur in vivo after exposure to the compound seems to be due to the inhibition of AurkB. ZM447439 induced growth inhibition of several human leukemia cell lines in vitro (Ikezoe T, Yang J, Nishioka C, et al. A novel treatment strategy targeting Aurora kinases in acute myelogenous leukemia. Mol Cancer Ther 2007;6: 1851-7). AurKB levels and activity, along with survivin levels, increase upon irradiation; inhibition of AurKB with ZM447439 reverses this effect and suggests AurKB as a potential target for enhancing radiotherapy, particularly in combination with inhibitors of survivin. Kim KW et al. (2007) Int J Radiat Oncol Biol Phys.67: 1519-25. MK-0457, another small molecule Aurora kinase inhibitor whose phenotypic effects in cancer cells appear to be due to AurkB inhibition, has demonstrated synergistic anti-leukemic activity with the chemotherapeutic drug vorinostat, a histone deacetylase inhibitor, in vitro. Fiskus, W. et al. Cotreatment with vorinostat enhances activity of MK-0457 (VX-680) against acute and chronic myelogenous leukemia cells .Clin Cancer Res 2008; 14:6106- 61 15. AurkA and AurkB were systematically compared as therapeutic targets for cancer, using antisense inhibitors specific for one of the two targets. Warner, SL et al., Comparing Aurora A and Aurora B as molecular targets for growth inhibition of pancreatic cancer cells; Mol Cancer Ther October 2006 5; 2450-2457. The authors concluded that AurkA and AurkB should be treated autonomously as valid targets which can be targeted independently or in

combination, although targeting AurkA had certain advantages over AurkB. The authors found no advantage to targeting both AurkA and AurkB simultaneously.

Inhibitors of AurkB include small molecules including those described above, antibodies (including commercially available Cat. No. 49-366 available from ProSci Inc., Poway CA), antisense molecules and small inhibitory RNAs (siRNA). US Patent 7615627 and PCT application WO08035365 disclose short nucleic acid molecules, such as short interfering nucleic acid molecules, for inhibiting expression of AurkB, as well as methods relating to cancer. US patent application publication no. US20060178318 and corresponding PCT application WO/2005/002571 disclose methods of treating cancer comprising administering an Aurora kinase inhibitor and a mitotic spindle assembly inhibitor. US patent 7,678,896 (Dharmacon Inc.) discloses methods, compositions, and kits which use siRNAs, including those directed to STK12. siRNA inhibitors targeted to particular regions of the AurkB (STK-12) sequence are also disclosed in US patent application publication no.

US2010144552 (Dharmacon). US US2010184047 and WO2008120812 (Oncotherapy Science) disclose antisense and siRNA compounds that inhibit CDCA8 or AurK.

SUMMARY OF INVENTION

In accordance with the present invention, a series of different LNA oligomers were designed to target different regions of human AurkB (GenBank accession number

NM_004217 - VERSION NM_004217.2 Gl:83776599)

The invention provides an oligomer of from 10 - 50 nucleotides in length, e.g. 10 - 30 nucleotides in length, which comprises a contiguous nucleotide sequence (a first region) of a total of from 10 - 30 nucleotides, wherein said contiguous nucleotide sequence (a first region) is at least 80% (e.g., 85%, 90%, 95%, 98%, or 99%) homologous to a region corresponding to the reverse complement of a mammalian aurora kinase B gene or mRNA, such as NM_004217 (SEQ ID NO:20) or naturally occurring variant thereof. Thus, for example, the oligomer hybridizes to a single stranded nucleic acid molecule having the sequence of a portion of NM_004217 (SEQ ID NO:20).

The invention provides for a conjugate comprising the oligomer according to the invention, and at least one non-nucleotide or non-polynucleotide moiety covalently attached to said oligomer.

The invention provides for a pharmaceutical composition comprising the oligomer or the conjugate according to the invention, and a pharmaceutically acceptable diluent, carrier, salt or adjuvant. The invention provides for the oligomer or the conjugate according to invention, for use as a medicament, such as for the treatment of cancer.

The invention provides for the use of an oligomer or the conjugate according to the invention, for the manufacture of a medicament for the treatment of cancer.

The invention provides for a method of treating cancer, said method comprising administering an, e.g. effective dose of, an oligomer, a conjugate or a pharmaceutical composition according to the invention, to a patient suffering from, or likely to suffer from cancer(such as a patient suffering from or susceptible to the disease or disorder).

In one embodiment, the disease or disorder or condition is associated with

overexpression of aurora kinase B.

The invention provides for a method for the inhibition of aurora kinase B in a cell which is expressing aurora kinase B, said method comprising administering an oligomer, or a conjugate according to the invention to said cell so as to affect the inhibition of aurora kinase B in said cell.

The invention provides an oligomer of from 10-50 monomers, which comprises a first region of 10-50 contiguous monomers, wherein the sequence of the first region is at least 80% identical to a region corresponding to a mammalian aurora kinase B gene or to the reverse complement of a target region of a nucleic acid which encodes a mammalian aurora kinase B.

The invention further provides a conjugate comprising the oligomer according to the invention, which comprises at least one non-nucleotide or non-polynucleotide moiety ("conjugated moiety") covalently attached to the oligomer of the invention.

The invention provides for pharmaceutical compositions comprising an oligomer or conjugate of the invention, and a pharmaceutically acceptable diluent, carrier, salt or adjuvant.

The invention further provides for an oligomer according to the invention, for use in medicine.

The invention further provides for the use of the oligomer of the invention for the manufacture of a medicament for the treatment of one or more of the diseases referred to herein, such as a disease selected from the group consisting of cancer.

The invention further provides for an oligomer according to the invention, for use for the treatment of one or more of the diseases referred to herein, such as a disease selected from the group consisting of cancer.

Pharmaceutical and other compositions comprising an oligomer of the invention are also provided. Further provided are methods of down-regulating the expression of aurora kinase B in cells or tissues comprising contacting said cells or tissues, in vitro or in vivo, with an effective amount of one or more of the oligomers, conjugates or compositions of the invention.

Also disclosed are methods of treating an animal (a non-human animal or a human) suspected of having, or susceptible to, a disease or condition, associated with expression, or over-expression of aurora kinase B by administering to the non-human animal or human a therapeutically or prophylactically effective amount of one or more of the oligomers, conjugates or pharmaceutical compositions of the invention. Further, methods of using oligomers for the inhibition of expression of aurora kinase B, and for treatment of diseases associated with activity of aurora kinase B are provided.

The invention provides for a method for treating a disease selected from the group consisting of: cancer, the method comprising administering an effective amount of one or more oligomers, conjugates, or pharmaceutical compositions thereof to an animal in need thereof (such as a patient in need thereof).

The invention provides for methods of inhibiting (e.g., by down-regulating) the expression of aurora kinase B in a cell or a tissue, the method comprising the step of contacting the cell or tissue, in vitro or in vivo, with an effective amount of one or more oligomers, conjugates, or pharmaceutical compositions thereof, to affect down-regulation of expression of aurora kinase B.

BRIEF DESCRIPTION OF FIGURES Figure 1 is a bar graph showing the results of evaluation of the oligonucleotides shown in Table 1 in the HeLa cell line for their potential to knock down AurkB expression at concentrations of 1 and 5 nM using lipid transfection.

Figure 2 is a bar graph showing the results of evaluation of the oligonucleotides shown in Table 1 in the HeLa cell line for their potential to knock down AurkB expression at concentrations of 1 and 5 and 25 μΜ using natural uptake without any transfection vehicle.

DETAILED DESCRIPTION OF INVENTION The Oligomer

The present invention employs oligomeric compounds (referred herein as oligomers), for use in modulating the function of nucleic acid molecules encoding mammalian aurora kinase B, such as the aurora kinase B nucleic acid of Genbank Accession No. NM_004217 (SEQ ID NO: 20), and naturally occurring variants of such nucleic acid molecules encoding mammalian aurora kinase B. The term "oligomer" in the context of the present invention, refers to a molecule formed by covalent linkage of two or more nucleotides (i.e. an oligonucleotide). Herein, a single nucleotide (unit) may also be referred to as a monomer or unit. In some embodiments, the terms "nucleoside", "nucleotide", "unit" and "monomer" are used interchangeably. It will be recognised that when referring to a sequence of nucleotides or monomers, what is referred to is the sequence of bases, such as A, T, G, C or U.

The oligomer consists or comprises of a contiguous nucleotide sequence of from 10 - 50, such as 10 - 30 nucleotides in length.

In various embodiments, the compound of the invention does not comprise RNA (units). It is preferred that the compound according to the invention is a linear molecule or is synthesised as a linear molecule. The oligomer is a single stranded molecule, and preferably does not comprise short regions of, for example, at least 3, 4 or 5 contiguous nucleotides, which are complementary to equivalent regions within the same oligomer (i.e. duplexes) - in this regards, the oligomer is not (essentially) double stranded. In some embodiments, the oligomer is essentially not double stranded, such as is not a siRNA. In various

embodiments, the oligomer of the invention may consist entirely of the contiguous nucleotide region. Thus, the oligomer is not substantially self-complementary.

The Target

Suitably the oligomer of the invention is capable of down-regulating (e.g. reducing or removing) expression of the aurora kinase B gene. In this regards, the oligomer of the invention can affect the inhibition of aurora kinase B, typically in a mammalian such as a human cell, such as a HeLa cell. In some embodiments, the oligomers of the invention bind to the target nucleic acid and affect inhibition of expression of at least 10% or 20% compared to the normal expression level, more preferably at least a 30%, 40%, 50%, 60%, 70%, 80%, 90% or 95% inhibition compared to the normal expression level (such as the expression level in the absence of the oligomer(s) or conjugate(s)). In some embodiments, such modulation is seen when using from 0.04 and 25nM, such as from 0.8 and 20nM concentration of the compound of the invention. In the same or a different embodiment, the inhibition of expression is less than 100%, such as less than 98% inhibition, less than 95% inhibition, less than 90% inhibition, less than 80% inhibition, such as less than 70% inhibition. Modulation of expression level may be determined by measuring protein levels, e.g. by the methods such as SDS-PAGE followed by western blotting using suitable antibodies raised against the target protein. Alternatively, modulation of expression levels can be determined by measuring levels of mRNA, e.g. by northern blotting or quantitative RT-PCR. When measuring via mRNA levels, the level of down-regulation when using an appropriate dosage, such as from 0.04 and 25nM, such as from 0.8 and 20nM concentration, is, In some embodiments, typically to a level of from 10-20% the normal levels in the absence of the compound, conjugate or composition of the invention.

As illustrated herein the cell type may, in some embodiments, be HeLa cells (e.g. in vitro - transfected cells). The oligomer concentration used (e.g. in HeLa cells) may, in some embodiments, be 5nM. The oligomer concentration used may, in some embodiments be 25nM (e.g. in HeLa cells). The oligomer concentration used may, in some embodiments be 1 nM (e.g. in HeLa cells). It should be noted that the concentration of oligomer used to treat the cell is typically performed in an in vitro cell assay, using transfection (Lipofecton), as illustrated in the examples. In the absence of a transfection agent, the oligo concentration required to obtain the down-regulation of the target is typically between 1 and 25μΜ, such as

5μΜ.

As used herein, the phrase "potent inhibitor" refers to an oligomer with an IC50 of less than 5nM as determined by the lipofectamine transfection assay as described in the

Examples hereinbelow. In some embodiments, the IC50 is less than 4nM, such as less than 2nM.

The invention therefore provides a method of down-regulating or inhibiting the expression of aurora kinase B protein and/or mRNA in a cell which is expressing aurora kinase B protein and/or mRNA, said method comprising administering the oligomer or conjugate according to the invention to said cell to down-regulating or inhibiting the expression of aurora kinase B protein and/or mRNA in said cell. Suitably the cell is a mammalian cell such as a human cell. The administration may occur, in some embodiments, in vitro. The administration may occur, in some embodiments, in vivo.

The term "target nucleic acid", as used herein refers to the DNA or RNA encoding mammalian aurora kinase B polypeptide, such as human aurora kinase B, such as

NM_004217, aurora kinase B encoding nucleic acids or naturally occurring variants thereof, and RNA nucleic acids derived therefrom, preferably mRNA, such as pre-mRNA, although preferably mature mRNA. In some embodiments, for example when used in research or diagnostics the "target nucleic acid" may be a cDNA or a synthetic oligonucleotide derived from the above DNA or RNA nucleic acid targets. The oligomer according to the invention is preferably capable of hybridising to the target nucleic acid. It will be recognised that

NM_004217 is a cDNA sequences, and as such, corresponds to the mature mRNA target sequence, although uracil is replaced with thymidine in the cDNA sequences.

The term "naturally occurring variant thereof" refers to variants of the aurora kinase B polypeptide of nucleic acid sequence which exist naturally within the defined taxonomic group, such as mammalian, such as mouse, monkey, and preferably human. Typically, when referring to "naturally occurring variants" of a polynucleotide the term also may encompass any allelic variant of the aurora kinase B encoding genomic DNA by chromosomal translocation or duplication, and the RNA, such as mRNA derived therefrom. "Naturally occurring variants" may also include variants derived from alternative splicing of the aurora kinase B mRNA. When referenced to a specific polypeptide sequence, e.g., the term also includes naturally occurring forms of the protein which may therefore be

processed, e.g. by co- or post-translational modifications, such as signal peptide cleavage, proteolytic cleavage, glycosylation, etc.

Sequences

The oligomers comprise or consist of a contiguous nucleotide sequence which corresponds to the reverse complement of a nucleotide sequence present in NM_004217. Thus, the oligomer can comprise or consist of, or a sequence selected from the group consisting of SEQ ID NOS: 1-19, wherein said oligomer (or contiguous nucleotide portion thereof) may optionally have one, two, or three mismatches against said selected sequence.

The oligomer may comprise or consist of a contiguous nucleotide sequence which is fully complementary (perfectly complementary) to the equivalent region of a nucleic acid which encodes a mammalian aurora kinase B (e.g., GenBank accession number

NM_004217). Thus, the oligomer can comprise or consist of an antisense nucleotide sequence.

However, in some embodiments, the oligomer may tolerate 1 , 2, 3, or 4 (or more) mismatches, when hybridising to the target sequence and still sufficiently bind to the target to show the desired effect, i.e. down-regulation of the target. Mismatches may, for example, be compensated by increased length of the oligomer nucleotide sequence and/or an increased number of nucleotide analogues, such as LNA, present within the nucleotide sequence.

In some embodiments, the contiguous nucleotide sequence comprises no more than 3, such as no more than 2 mismatches when hybridizing to the target sequence, such as to the corresponding region of a nucleic acid which encodes a mammalian aurora kinase B.

In some embodiments, the contiguous nucleotide sequence comprises no more than a single mismatch when hybridizing to the target sequence, such as the corresponding region of a nucleic acid which encodes a mammalian aurora kinase B.

The nucleotide sequence of the oligomers of the invention or the contiguous nucleotide sequence is preferably at least 80% homologous to a corresponding sequence selected from the group consisting of SEQ ID NOS: 1-19, such as at least 85%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96% homologous, at least 97% homologous, at least 98% homologous, at least 99% homologous, such as 100% homologous (identical). The nucleotide sequence of the oligomers of the invention or the contiguous nucleotide sequence is preferably at least 80% homologous to the reverse complement of a

corresponding sequence present in NM_004217, such as at least 85%, at least 90%, at least 91 %, at least 92%at least 93%, at least 94%, at least 95%, at least 96% homologous, at least 97% homologous, at least 98% homologous, at least 99% homologous, such as 100% homologous (identical).

The nucleotide sequence of the oligomers of the invention or the contiguous nucleotide sequence is preferably at least 80% complementary to a sub-sequence present in

NM_004217, such as at least 85%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96% complementary, at least 97% complementary, at least 98% complementary, at least 99% complementary, such as 100% complementary (perfectly complementary).

In some embodiments, the term "first region" as used herein refers to a portion (subsequence) of an oligomer.

In some embodiments the oligomer (or contiguous nucleotide portion thereof) is selected from, or comprises, one of the sequences selected from the group consisting of SEQ ID NOS: 1-19, or a sub-sequence of at least 10 contiguous nucleotides thereof, wherein said oligomer (or contiguous nucleotide portion thereof) may optionally comprise one, two, or three mismatches when compared to the sequence.

In some embodiments the sub-sequence may consist of 11 , 12, 13, 14, 15, 16, 17, 18,

19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, or 29 contiguous nucleotides, such as from 12 -22, such as from 12-18 nucleotides. Suitably, in some embodiments, the sub-sequence is of the same length as the contiguous nucleotide sequence of the oligomer of the invention.

However, it is recognised that, in some embodiments the nucleotide sequence of the oligomer may comprise additional 5' or 3' nucleotides, such as, independently, 1 , 2, 3, 4 or 5 additional nucleotides 5' and/or 3', which are non-complementary to the target sequence. In this respect the oligomer of the invention, may, in some embodiments, comprise a contiguous nucleotide sequence which is flanked 5' and or 3' by additional nucleotides. In some embodiments the additional 5' or 3' nucleotides are naturally occurring nucleotides, such as DNA or RNA. In some embodiments, the additional 5' or 3' nucleotides may represent region D as referred to in the context of gapmer oligomers herein.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 21 , or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 22, or a sub-sequence thereof. In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 23, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO:24 or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 25, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 26, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 27, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO:28 or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 29, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 30, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 31 , or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 32 or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 33, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 34, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 35, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 36 or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 37, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 38, or a sub-sequence thereof.

In some embodiments the oligomer according to the invention consists or comprises of a nucleotide sequence according to SEQ ID NO: 39, or a sub-sequence thereof. In determining the degree of "complementarity" between oligomers of the invention (or regions thereof) and the target region of the nucleic acid which encodes mammalian aurora kinase B, such as those disclosed herein, the degree of "complementarity" (also, "homology" or "identity") is expressed as the percentage identity (or percentage homology) between the sequence of the oligomer (or region thereof) and the sequence of the target region (or the reverse complement of the target region) that best aligns therewith. The percentage is calculated by counting the number of aligned bases that are identical between the 2 sequences, dividing by the total number of contiguous monomers in the oligomer, and multiplying by 100. In such a comparison, if gaps exist, it is preferable that such gaps are merely mismatches rather than areas where the number of monomers within the gap differs between the oligomer of the invention and the target region.

As used herein, the terms "homologous" and "homology" are interchangeable with the terms "identical" and "identity".

The terms "corresponding to" and "corresponds to" refer to the comparison between the nucleotide sequence of the oligomer (i.e. the nucleobase or base sequence) or contiguous nucleotide sequence (a first region) and the equivalent contiguous nucleotide sequence of a further sequence selected from either i) a sub-sequence of the reverse complement of the nucleic acid target, such as the mRNA which encodes the aurora kinase B protein, such as NM_004217, and/or ii) the sequence of nucleotides provided herein such as the group consisting of SEQ ID NOS: 1-19, or sub-sequence thereof. Nucleotide analogues are compared directly to their equivalent or corresponding nucleotides. A first sequence which corresponds to a further sequence under i) or ii) typically is identicial to that sequence over the length of the first sequence (such as the contiguous nucleotide sequence) or, as described herein may, in some embodiments, is at least 80% homologous to a corresponding sequence, such as at least 85%, at least 90%, at least 91 %, at least 92%at least 93%, at least 94%, at least 95%, at least 96% homologous, such as 100% homologous (identical).

The terms "corresponding nucleotide analogue" and "corresponding nucleotide" are intended to indicate that the nucleotide in the nucleotide analogue and the naturally occurring nucleotide are identical. For example, when the 2-deoxyribose unit of the nucleotide is linked to an adenine, the "corresponding nucleotide analogue" contains a pentose unit (different from 2-deoxyribose) linked to an adenine.

The terms "reverse complement", "reverse complementary" and "reverse

complementarity" as used herein are interchangeable with the terms "complement",

"complementary" and "complementarity".

Length The oligomers may comprise or consist of a contiguous nucleotide sequence of a total of 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 , 22, 23, 24, 25, 26, 27, 28, 29 or 30 contiguous nucleotides in length.

In some embodiments, the oligomers comprise or consist of a contiguous nucleotide sequence of a total of from 10 - 22 nucleotides, such as 12 - 18, 13 - 17 or 12 - 16 nucleotides, such as 13, 14, 15, 16 contiguous nucleotides in length.

In some embodiments, the oligomers comprise or consist of a contiguous nucleotide sequence of a total of 10, 11 , 12, 13, or 14 contiguous nucleotides in length.

In some embodiments, the oligomer according to the invention consists of no more than 22 nucleotides, such as no more than 20 nucleotides, such as no more than 18 nucleotides, such as 15, 16 or 17 nucleotides. In some embodiments the oligomer of the invention comprises less than 20 nucleotides. It should be understood that when a range is given for an oligomer, or contiguous nucleotide sequence length it includes the lower an upper lengths provided in the range, for example from (or between) 10 - 30, includes both 10 and 30.

Nucleosides and Nucleoside analogues

In some embodiments, the terms "nucleoside analogue" and "nucleotide analogue" are used interchangeably.

The term "nucleotide" as used herein, refers to a glycoside comprising a sugar moiety, a base moiety and a covalently linked group (linkage group), such as a phosphate or phosphorothioate internucleotide linkage group, and covers both naturally occurring nucleotides, such as DNA or RNA, and non-naturally occurring nucleotides comprising modified sugar and/or base moieties, which are also referred to as "nucleotide analogues" herein. Herein, a single nucleotide (unit) may also be referred to as a monomer or nucleic acid unit.

In field of biochemistry, the term "nucleoside" is commonly used to refer to a glycoside comprising a sugar moiety and a base moiety, and may therefore be used when referring to the nucleotide units, which are covalently linked by the internucleotide linkages between the nucleotides of the oligomer. In the field of biotechnology, the term "nucleotide" is often used to refer to a nucleic acid monomer or unit, and as such in the context of an oligonucleotide may refer to the base - such as the "nucleotide sequence", typically refer to the nucleobase sequence (i.e. the presence of the sugar backbone and internucleoside linkages are implicit). Likewise, particularly in the case of oligonucleotides where one or more of the

internucleoside linkage groups are modified, the term "nucleotide" may refer to a "nucleoside" for example the term "nucleotide" may be used, even when specifiying the presence or nature of the linkages between the nucleosides. As one of ordinary skill in the art would recognise, the 5' terminal nucleotide of an oligonucleotide does not comprise a 5' internucleotide linkage group, although may or may not comprise a 5' terminal group.

Non-naturally occurring nucleotides include nucleotides which have modified sugar moieties, such as bicyclic nucleotides or 2' modified nucleotides, such as 2' substituted nucleotides.

"Nucleotide analogues" are variants of natural nucleotides, such as DNA or RNA nucleotides, by virtue of modifications in the sugar and/or base moieties. Analogues could in principle be merely "silent" or "equivalent" to the natural nucleotides in the context of the oligonucleotide, i.e. have no functional effect on the way the oligonucleotide works to inhibit target gene expression. Such "equivalent" analogues may nevertheless be useful if, for example, they are easier or cheaper to manufacture, or are more stable to storage or manufacturing conditions, or represent a tag or label. Preferably, however, the analogues will have a functional effect on the way in which the oligomer works to inhibit expression; for example by producing increased binding affinity to the target and/or increased resistance to intracellular nucleases and/or increased ease of transport into the cell. Specific examples of nucleoside analogues are described by e.g. Freier & Altmann; Nucl. Acid Res., 1997, 25, 4429-4443 and Uhlmann; Curr. Opinion in Drug Development, 2000, 3(2), 293-213, and in Scheme 1 :

Phosphorthioate 2'-0-Methyl 2'-MOE 2'-Fluoro

Boranophosphate s

Scheme 1

The oligomer may thus comprise or consist of a simple sequence of natural occurring nucleotides - preferably 2'-deoxynucleotides (referred to here generally as "DNA"), but also possibly ribonucleotides (referred to here generally as "RNA"), or a combination of such naturally occurring nucleotides and one or more non-naturally occurring nucleotides, i.e. nucleotide analogues. Such nucleotide analogues may suitably enhance the affinity of the oligomer for the target sequence.

Examples of suitable and preferred nucleotide analogues are provided by

WO2007/031091 or are referenced therein.

Incorporation of affinity-enhancing nucleotide analogues in the oligomer, such as LNA or 2'-substituted sugars, can allow the size of the specifically binding oligomer to be reduced, and may also reduce the upper limit to the size of the oligomer before non-specific or aberrant binding takes place.

In some embodiments, the oligomer comprises at least 1 nucleoside analogue. In some embodiments the oligomer comprises at least 2 nucleotide analogues. In some embodiments, the oligomer comprises from 3-8 nucleotide analogues, e.g. 6 or 7 nucleotide analogues. In the by far most preferred embodiments, at least one of said nucleotide analogues is a locked nucleic acid (LNA); for example at least 3 or at least 4, or at least 5, or at least 6, or at least 7, or 8, of the nucleotide analogues may be LNA. In some embodiments all the nucleotides analogues may be LNA.

It will be recognised that when referring to a preferred nucleotide sequence motif or nucleotide sequence, which consists of only nucleotides, the oligomers of the invention which are defined by that sequence may comprise a corresponding nucleotide analogue in place of one or more of the nucleotides present in said sequence, such as LNA units or other nucleotide analogues, which raise the duplex stability/T_m of the oligomer/target duplex (i.e. affinity enhancing nucleotide analogues).

In some embodiments, any mismatches between the nucleotide sequence of the oligomer and the target sequence are preferably found in regions outside the affinity enhancing nucleotide analogues, such as region B as referred to herein, and/or region D as referred to herein, and/or at the site of non modified such as DNA nucleotides in the oligonucleotide, and/or in regions which are 5' or 3' to the contiguous nucleotide sequence.

Examples of such modification of the nucleotide include modifying the sugar moiety to provide a 2'-substituent group or to produce a bridged (locked nucleic acid) structure which enhances binding affinity and may also provide increased nuclease resistance.

A preferred nucleotide analogue is LNA, such as oxy-LNA (such as beta-D-oxy-LNA, and alpha-L-oxy-LNA), and/or amino-LNA (such as beta-D-amino-LNA and alpha-L-amino- LNA) and/or thio-LNA (such as beta-D-thio-LNA and alpha-L-thio-LNA) and/or ENA (such as beta-D-ENA and alpha-L-ENA). Most preferred is beta-D-oxy-LNA.

In some embodiments the nucleotide analogues present within the oligomer of the invention (such as in regions A and C mentioned herein) are independently selected from, for example: 2'-0-alkyl-RNA units, 2'-amino-DNA units, 2'-fluoro-DNA units, LNA units, arabino nucleic acid (ANA) units, 2'-fluoro-ANA units, HNA units, INA (intercalating nucleic acid - Christensen, 2002. Nucl. Acids. Res. 2002 30: 4918-4925, hereby incorporated by reference) units and 2'MOE units. In some embodiments there is only one of the above types of nucleotide analogues present in the oligomer of the invention, or contiguous nucleotide sequence thereof. In some embodiments the nucleotide analogues are 2'-0-methoxyethyl-RNA (2'MOE), 2'-fluoro-DNA monomers or LNA nucleotide analogues, and as such the oligonucleotide of the invention may comprise nucleotide analogues which are independently selected from these three types of analogue, or may comprise only one type of analogue selected from the three types. In some embodiments at least one of said nucleotide analogues is 2'-MOE-RNA, such as 2, 3, 4, 5, 6, 7, 8, 9 or 10 2'-MOE-RNA nucleotide units. In some embodiments at least one of said nucleotide analogues is 2'-fluoro DNA, such as 2, 3, 4, 5, 6, 7, 8, 9 or 10 2'- fluoro-DNA nucleotide units.

In some embodiments, the oligomer according to the invention comprises at least one Locked Nucleic Acid (LNA) unit, such as 1 , 2, 3, 4, 5, 6, 7, or 8 LNA units, such as from 3 - 7 or 4 to 8 LNA units, or 3, 4, 5, 6 or 7 LNA units. In some embodiments, all the nucleotide analogues are LNA. In some embodiments, the oligomer may comprise both beta-D-oxy- LNA, and one or more of the following LNA units: thio-LNA, amino-LNA, oxy-LNA, and/or ENA in either the beta-D or alpha-L configurations or combinations thereof. In some embodiments all LNA cytosine units are 5'methyl-Cytosine. In some embodiments of the invention, the oligomer may comprise both LNA and DNA units. Preferably the combined total of LNA and DNA units is 10-25, such as 10 - 24, preferably 10-20, such as 10 - 18, even more preferably 12-16. In some embodiments of the invention, the nucleotide sequence of the oligomer, such as the contiguous nucleotide sequence consists of at least one LNA and the remaining nucleotide units are DNA units. In some embodiments the oligomer comprises only LNA nucleotide analogues and naturally occurring nucleotides (such as RNA or DNA, most preferably DNA nucleotides), optionally with modified internucleotide linkages such as phosphorothioate.

The term "nucleobase" refers to the base moiety of a nucleotide and covers both naturally occurring as well as non-naturally occurring variants. Thus, "nucleobase" covers not only the known purine and pyrimidine heterocycles but also heterocyclic analogues and tautomers thereof.

Examples of nucleobases include, but are not limited to adenine, guanine, cytosine, thymidine, uracil, xanthine, hypoxanthine, 5-methylcytosine, isocytosine, pseudoisocytosine, 5-bromouracil, 5-propynyluracil, 6-aminopurine, 2-aminopurine, inosine, diaminopurine, and 2-chloro-6-aminopurine.

In some embodiments, at least one of the nucleobases present in the oligomer is a modified nucleobase selected from the group consisting of 5-methylcytosine, isocytosine, pseudoisocytosine, 5-bromouracil, 5-propynyluracil, 6-aminopurine, 2-aminopurine, inosine, diaminopurine, and 2-chloro-6-aminopurine. LNA

The term "LNA" refers to a bicyclic nucleoside analogue, known as "Locked Nucleic Acid". It may refer to an LNA monomer, or, when used in the context of an "LNA

oligonucleotide", LNA refers to an oligonucleotide containing one or more such bicyclic nucleotide analogues. LNA nucleotides are characterised by the presence of a linker group (such as a bridge) between C2' and C4' of the ribose sugar ring - for example as shown as the biradical R^4* - R^2* as described below.

The LNA used in the oligonucleotide compounds of the invention preferably has the structure of the eneral formula I

Formula 1

wherein for all chiral centers, asymmetric groups may be found in either R or S orientation;

wherein X is selected from -0-, -S-, -N(R^N*)-, -C(R⁶R^6*)-, such as, in some

embodiments -0-;

B is selected from hydrogen, optionally substituted Ci_-4-alkoxy, optionally substituted

Ci_-4-alkyl, optionally substituted Ci_-4-acyloxy, nucleobases including naturally occurring and nucleobase analogues, DNA intercalators, photochemically active groups, thermochemically active groups, chelating groups, reporter groups, and ligands; preferably, B is a nucleobase or nucleobase analogue;

P designates an internucleotide linkage to an adjacent monomer, or a 5'-terminal group, such internucleotide linkage or 5'-terminal group optionally including the substituent R⁵ or equally applicable the substituent R^5*;

P* designates an internucleotide linkage to an adjacent monomer, or a 3'-terminal group;

R^4* and R^2* together designate a bivalent linker group consisting of 1 - 4 groups/atoms selected from -C(R^aR^b)-, -C(R^a)=C(R^b)-, -C(R^a)=N-, -0-, -Si(R^a)₂-, -S-, -S0₂-, -N(R^a)-, and >C=Z, wherein Z is selected from -0-, -S-, and -N(R^a)-, and R^a and R^b each is independently selected from hydrogen, optionally substituted Ci_i₂-alkyl, optionally substituted C_2-i2-alkenyl, optionally substituted C_2-i2-alkynyl, hydroxy, optionally substituted Ci-12-alkoxy, C2-12- alkoxyalkyl, C_2-i2-alkenyloxy, carboxy, Ci-12-alkoxycarbonyl, Ci-12-alkylcarbonyl, formyl, aryl, aryloxy-carbonyl, aryloxy, arylcarbonyl, heteroaryl, heteroaryloxy-carbonyl, heteroaryloxy, heteroarylcarbonyl, amino, mono- and di(Ci_-6-alkyl)amino, carbamoyl, mono- and di(Ci_-6- alkyl)-amino-carbonyl, amino-Ci_-6-alkyl-aminocarbonyl, mono- and di(Ci-6-alkyl)amino-Ci-₆- alkyl-aminocarbonyl, Ci_-6-alkyl-carbonylamino, carbamido, Ci_-6-alkanoyloxy, sulphono, Ci_-6- alkylsulphonyloxy, nitro, azido, sulphanyl, Ci_-6-alkylthio, halogen, DNA intercalators, photochemically active groups, thermochemically active groups, chelating groups, reporter groups, and ligands, where aryl and heteroaryl may be optionally substituted and where two geminal substituents R^a and R^b together may designate optionally substituted methylene (=CH₂), wherein for all chiral centers, asymmetric groups may be found in either R or S orientation, and;

each of the substituents R^1*, R², R³, R⁵, R^5*, R⁶ and R^6*, which are present is independently selected from hydrogen, optionally substituted Ci-12-alkyl, optionally substituted C_2-i2-alkenyl, optionally substituted C_2-i2-alkynyl, hydroxy, Ci-12-alkoxy, C2-12- alkoxyalkyl, C_2-i2-alkenyloxy, carboxy, Ci-12-alkoxycarbonyl, Ci-12-alkylcarbonyl, formyl, aryl, aryloxy-carbonyl, aryloxy, arylcarbonyl, heteroaryl, heteroaryloxy-carbonyl, heteroaryloxy, heteroarylcarbonyl, amino, mono- and di(Ci_-6-alkyl)amino, carbamoyl, mono- and di(Ci_-6- alkyl)-amino-carbonyl, amino-Ci_-6-alkyl-aminocarbonyl, mono- and di(Ci-6-alkyl)amino-Ci-₆- alkyl-aminocarbonyl, Ci_-6-alkyl-carbonylamino, carbamido, Ci_-6-alkanoyloxy, sulphono, Ci_-6- alkylsulphonyloxy, nitro, azido, sulphanyl, Ci_-6-alkylthio, halogen, DNA intercalators, photochemically active groups, thermochemically active groups, chelating groups, reporter groups, and ligands, where aryl and heteroaryl may be optionally substituted, and where two geminal substituents together may designate oxo, thioxo, imino, or optionally substituted methylene; ; wherein R^N is selected from hydrogen and Ci_-4-alkyl, and where two adjacent (non-geminal) substituents may designate an additional bond resulting in a double bond; and R^N*, when present and not involved in a biradical, is selected from hydrogen and Ci_-4-alkyl; and basic salts and acid addition salts thereof. For all chiral centers, asymmetric groups may be found in either R or S orientation.

In some embodiments, R^4* and R^2* together designate a biradical consisting of a groups selected from the group consisting of C(R^aR^b)-C(R^aR^b)-, C(R^aR^b)-0-, C(R^aR^b)-NR^a-, C(R^aR^b)-S-, and C(R^aR^b)-C(R^aR^b)-0-, wherein each R^a and R^b may optionally be

independently selected. In some embodiments, R^a and R^b may be, optionally independently selected from the group consisting of hydrogen and _Ci-₆alkyl, such as methyl, such as hydrogen. In some embodiments, R^4* and R^2* together designate the biradical -0-CH(CH₂OCH₃)- (2'0-methoxyethyl bicyclic nucleic acid - Seth at al., 2010, J. Org. Chem) - in either the R- or S- configuration.

In some embodiments, R^4* and R^2* together designate the biradical -0-CH(CH₂CH₃)- (2'0-ethyl bicyclic nucleic acid - Seth at al., 2010, J. Org. Chem). - in either the R- or S- configuration.

In some embodiments, R^4* and R^2* together designate the biradical -0-CH(CH₃)-. - in either the R- or S- configuration. In some embodiments, R^4* and R^2* together designate the biradical -0-CH₂-0-CH₂- - (Seth at al., 2010, J. Org. Chem).

In some embodiments, R^4* and R^2* together designate the biradical -0-NR-CH₃- -

(Seth at al., 2010, J. Org. Chem) .

In some embodiments, the LNA units have a structure selected from the following group:

In some embodiments, R^1*, R², R³, R⁵, R^5* are independently selected from the group consisting of hydrogen, halogen, Ci_₆ alkyl, substituted Ci_₆ alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci_-6 aminoalkyl or substituted Ci_-6 aminoalkyl. For all chiral centers, asymmetric groups may be found in either R or S orientation.

In some embodiments, R^1*, R², R³, R⁵, R^5* are hydrogen.

In some embodiments, R^1*, R², R³ are independently selected from the group consisting of hydrogen, halogen, Ci_-6 alkyl, substituted Ci_-6 alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci_-6 aminoalkyl or substituted Ci_-6 aminoalkyl. For all chiral centers, asymmetric groups may be found in either R or S orientation.

In some embodiments, R^1*, R², R³ are hydrogen.

In some embodiments, R⁵ and R^5* are each independently selected from the group consisting of H, -CH₃, -CH₂-CH₃,- CH₂-0-CH₃, and -CH=CH₂. Suitably in some

embodiments, either R⁵ or R^5* are hydrogen, where as the other group (R⁵ or R^5*

respectively) is selected from the group consisting of Ci_-5 alkyl, C_2-6 alkenyl, C_2-6 alkynyl, substituted Ci_₆ alkyl, substituted C_2-6 alkenyl, substituted C_2-6 alkynyl or substituted acyl (- C(=0)-); wherein each substituted group is mono or poly substituted with substituent groups independently selected from halogen, Ci_-6 alkyl, substituted Ci_-6 alkyl, C_2-6 alkenyl, substituted C₂-₆ alkenyl, C₂-₆ alkynyl, substituted C₂-₆ alkynyl, OJi, SJi, NJiJ_2l N₃, COOJ₁, CN, O- C(=0)NJ₁J₂, N(H)C(=NH)NJ,J₂ or N(H)C(=X)N(H)J₂ wherein X is O or S; and each J, and J₂ is, independently, H, Ci_-6 alkyl, substituted Ci_-6 alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl, substituted C_2-6 alkynyl, Ci_-6 aminoalkyl, substituted Ci_-6 aminoalkyl or a protecting group. In some embodiments either R⁵ or R^5* is substituted Ci_-6 alkyl. In some

embodiments either R⁵ or R^5* is substituted methylene wherein preferred substituent groups include one or more groups independently selected from F, NJ^, N₃, CN, OJ₁, SJi, O-

C(=0)NJ₁J₂, N(H)C(=NH)NJ, J₂ or N(H)C(0)N(H)J₂. In some embodiments each J, and J₂ is, independently H or Ci_-6 alkyl. In some embodiments either R⁵ or R^5* is methyl, ethyl or methoxymethyl. In some embodiments either R⁵ or R^5* is methyl. In a further embodiment either R⁵ or R^5* is ethylenyl. In some embodiments either R⁵ or R^5* is substituted acyl. In some embodiments either R⁵ or R^5* is C(=0)NJ₁J₂. For all chiral centers, asymmetric groups may be found in either R or S orientation. Such 5' modified bicyclic nucleotides are disclosed in WO 2007/134181 , which is hereby incorporated by reference in its entirety.

In some embodiments B is a nucleobase, including nucleobase analogues and naturally occurring nucleobases, such as a purine or pyrimidine, or a substituted purine or substituted pyrimidine, such as a nucleobase referred to herein, such as a nucleobase selected from the group consisting of adenine, cytosine, thymine, adenine, uracil, and/or a modified or substituted nucleobase, such as 5-thiazolo-uracil, 2-thio-uracil, 5-propynyl-uracil, 2'thio-thymine, 5-methyl cytosine, 5-thiozolo-cytosine, 5-propynyl-cytosine, and 2,6- diaminopurine.

In some embodiments, R^4* and R^2* together designate a biradical selected from -

C(R^aR^b)-0-, -C(R^aR^b)-C(R^cR^d)-0-, -C(R^aR^b)-C(R^cR^d)-C(R^eR^f)-0-, -C(R^aR^b)-0-C(R^cR^d)-, - C(R^aR^b)-0-C(R^cR^d)-0-, -C(R^aR^b)-C(R^cR^d)-, -C(R^aR^b)-C(R^cR^d)-C(R^eR^f)-, - C(R^a)=C(R^b)-C(R^cR^d)-, -C(R^aR^b)-N(R^c)-, -C(R^aR^b)-C(R^cR^d)- N(R^e)-, -C(R^aR^b)-N(R^c)-0-, and - C(R^aR^b)-S-, -C(R^aR^b)-C(R^cR^d)-S-, wherein R^a, R^b, R^c, R^d, R^e, and R^f each is independently selected from hydrogen, optionally substituted Ci-i₂-alkyl, optionally substituted C_2-i₂-alkenyl, optionally substituted C_2-i₂-alkynyl, hydroxy, Ci-i₂-alkoxy, C_2-i₂-alkoxyalkyl, C_2-i₂-alkenyloxy, carboxy, Ci-i₂-alkoxycarbonyl, Ci-i₂-alkylcarbonyl, formyl, aryl, aryloxy-carbonyl, aryloxy, arylcarbonyl, heteroaryl, heteroaryloxy-carbonyl, heteroaryloxy, heteroarylcarbonyl, amino, mono- and di(Ci_-6-alkyl)amino, carbamoyl, mono- and di(Ci_-6-alkyl)-amino-carbonyl, amino- Ci-6-alkyl-aminocarbonyl, mono- and di(Ci-6-alkyl)amino-Ci-₆-alkyl-aminocarbonyl, Ci_-6-alkyl- carbonylamino, carbamido, Ci_-6-alkanoyloxy, sulphono, Ci_-6-alkylsulphonyloxy, nitro, azido, sulphanyl, Ci_-6-alkylthio, halogen, DNA intercalators, photochemically active groups, thermochemically active groups, chelating groups, reporter groups, and ligands, where aryl and heteroaryl may be optionally substituted and where two geminal substituents R^a and R^b together may designate optionally substituted methylene (=CH₂). For all chiral centers, asymmetric groups may be found in either R or S orientation.

In a further embodiment R^4* and R^2* together designate a biradical (bivalent group) selected from -CH₂-0-, -CH₂-S-, -CH₂-NH-, -CH₂-N(CH₃)-, -CH₂-CH₂-0-, -CH₂-CH(CH₃)-, - CH₂-CH₂-S-, -CH₂-CH₂-NH-, -CH₂-CH₂-CH₂-, -CH₂-CH₂-CH₂-0-, -CH₂-CH₂-CH(CH₃)-, - CH=CH-CH₂-, -CH₂-0-CH₂-0-, -CH₂-NH-0-, -CH₂-N(CH₃)-0-, -CH₂-0-CH₂-, -CH(CH₃)-0-, and -CH(CH₂-0-CH₃)-0-, and/or, -CH₂-CH₂-, and -CH=CH- For all chiral centers, asymmetric groups may be found in either R or S orientation.

In some embodiments, R^4* and R^2* together designate the biradical C(R^aR^b)-N(R^c)-0-, wherein R^a and R^b are independently selected from the group consisting of hydrogen, halogen, Ci_₆ alkyl, substituted Ci_₆ alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci_-6 aminoalkyl or substituted Ci_-6 aminoalkyl, such as hydrogen, and; wherein R^c is selected from the group consisting of hydrogen, halogen, Ci_-6 alkyl, substituted Ci_-6 alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci_-6 aminoalkyl or substituted Ci_-6 aminoalkyl, such as hydrogen.

In some embodiments, R^4* and R^2* together designate the biradical C(R^aR^b)-0-C(R^cR^d) -0-, wherein R^a, R^b, R^c, and R^d are independently selected from the group consisting of hydrogen, halogen, Ci_-6 alkyl, substituted Ci_-6 alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci-6 aminoalkyl or substituted Ci_-6 aminoalkyl, such as hydrogen.

In some embodiments, R^4* and R^2* form the biradical -CH(Z)-0-, wherein Z is selected from the group consisting of Ci_-6 alkyl, C_2-6 alkenyl, C_2-6 alkynyl, substituted Ci_-6 alkyl, substituted C_2-6 alkenyl, substituted C_2-6 alkynyl, acyl, substituted acyl, substituted amide, thiol or substituted thio; and wherein each of the substituted groups, is, independently, mono or poly substituted with optionally protected substituent groups independently selected from halogen, oxo, hydroxyl, OJi, NJiJ_2l SJi, N₃, OC(=X)Ji, OC(=X)NJ₁J₂, NJ³C(=X)NJ₁J₂ and CN, wherein each J₂ and J₃ is, independently, H or Ci_-6 alkyl, and X is O, S or N^. In some embodiments Z is Ci_-6 alkyl or substituted Ci_-6 alkyl. In some embodiments Z is methyl. In some embodiments Z is substituted Ci_-6 alkyl. In some embodiments said substituent group is Ci_-6 alkoxy. In some embodiments Z is CH₃OCH₂-. For all chiral centers,

asymmetric groups may be found in either R or S orientation. Such bicyclic nucleotides are disclosed in US 7,399,845 which is hereby incorporated by reference in its entirety. In some embodiments, R^1*, R², R³, R⁵, R^5* are hydrogen. In some some embodiments, R^1*, R², R^{3 *} are hydrogen, and one or both of R⁵, R^5* may be other than hydrogen as referred to above and in WO 2007/134181.

In some embodiments, R^4* and R^2* together designate a biradical which comprise a substituted amino group in the bridge such as consist or comprise of the biradical -CH₂-N( R^c)-, wherein R^c is Ci _ i₂ alkyloxy. In some embodiments R^4* and R^2* together designate a biradical -Cq₃q₄-NOR -, wherein q₃ and q are independently selected from the group consisting of hydrogen, halogen, Ci_₆ alkyl, substituted Ci_₆ alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci-₆ aminoalkyl or substituted Ci-₆ aminoalkyl; wherein each substituted group is, independently, mono or poly substituted with substituent groups independently selected from halogen, OJi, SJi, NJiJ_2l COOJi, ON, 0-C(=0)NJ₁J₂, N(H)C(=NH)N or N(H)C(=X=N(H)J₂ wherein X is O or S; and each of ^ and J₂ is, independently, H, Ci_-6 alkyl, C_2-6 alkenyl, C_2-6 alkynyl, Ci-₆ aminoalkyl or a protecting group. For all chiral centers, asymmetric groups may be found in either R or S orientation. Such bicyclic nucleotides are disclosed in WO2008/150729 which is hereby incorporated by reference in its entirity. In some embodiments, R^1*, R², R³, R⁵, R^5* are independently selected from the group consisting of hydrogen, halogen, Ci_-6 alkyl, substituted Ci_-6 alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2- 6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci-₆ aminoalkyl or substituted Ci-₆ aminoalkyl. In some embodiments, R^1*, R², R³, R⁵, R^5* are hydrogen. In some embodiments, R^1*, R², R³ are hydrogen and one or both of R⁵, R^5* may be other than hydrogen as referred to above and in WO 2007/134181. In some embodiments R^4* and R^2* together designate a biradical (bivalent group) C(R^aR^b)-0-, wherein R^a and R^b are each independently halogen, Ci-Ci₂ alkyl, substituted Ci-Ci₂ alkyl, C₂-Ci₂ alkenyl, substituted C₂-Ci₂ alkenyl, C₂-Ci₂ alkynyl, substituted C₂-Ci₂ alkynyl, Ci-Ci₂ alkoxy, substituted Ci-Ci₂ alkoxy, OJi SJi, SOJi, S0₂Ji, NJiJ_2l N₃, CN, C(=0)OJi, C(=0)NJ₁J₂, C(=0)Ji, O-

or R^a and R^b together are =C(q3)(q4); q₃ and q are each, independently, H, halogen, Ci-Ci₂alkyl or substituted C Ci2 alkyl; each substituted group is, independently, mono or poly substituted with substituent groups independently selected from halogen, Ci-C₆ alkyl, substituted Ci-C₆ alkyl, C₂- C₆ alkenyl, substituted C₂-C₆ alkenyl, C₂-C₆ alkynyl, substituted C₂-C₆ alkynyl, OJi, SJi, NJ^, N₃, CN,

0-C(=0)NJ₁J₂, N(H)C(=0)NJ₁J₂ or

N(H)C(=S)NJ₁J_2. and; each ^ and J₂ is, independently, H, C1-C₆ alkyl, substituted C1-C₆ alkyl, C₂-C₆ alkenyl, substituted C₂-C₆ alkenyl, C₂-C₆ alkynyl, substituted C₂-C₆ alkynyl, C1-C₆ aminoalkyl, substituted C1 -C₆ aminoalkyl or a protecting group. Such compounds are disclosed in WO2009006478A, hereby incorporated in its entirety by reference.

In some embodiments, R^4* and R^2* form the biradical - Q -, wherein Q is

C(qi)(q₂)C(q₃)(q4), C(qi)=C(q₃), C[=C(qi)(q₂)]-C(q₃)(q4) or C(qi)(q₂)-C[=C(q₃)(q₄)]; qi, q₂, q₃, q₄ are each independently. H, halogen, Ci_i₂ alkyl, substituted Ci_i₂ alkyl, C_2-i₂ alkenyl, substituted Ci-i₂ alkoxy, OJi , SJi , SOJi , S0₂Ji , NJiJ_2l N₃, CN,

, C(=0)-NJ₁J₂, C(=0) Ji , -C(=0)NJ₁J₂, N(H)C(=NH)NJ₁J₂, N(H)C(=0)NJ₁J₂ or N(H)C(=S)NJ₁J₂; each ^ and J₂ is, independently, H, Ci_-6 alkyl, C_2-6 alkenyl, C_2-6 alkynyl, Ci_-6 aminoalkyl or a protecting group; and, optionally wherein when Q is C(qi)(q₂)(q₃)(q₄) and one of q₃ or q₄ is CH₃ then at least one of the other of q₃ or q₄ or one of \ and q₂ is other than H. In some embodiments, R^1*, R², R³, R⁵, R^5* are hydrogen. For all chiral centers, asymmetric groups may be found in either R or S orientation. Such bicyclic nucleotides are disclosed in WO2008/154401 which is hereby incorporated by reference in its entirity. In some embodiments, R^1*, R², R³, R⁵, R^5* are independently selected from the group consisting of hydrogen, halogen, Ci_-6 alkyl, substituted Ci_-6 alkyl, C_2-6 alkenyl, substituted C_2-6 alkenyl, C_2-6 alkynyl or substituted C_2-6 alkynyl, Ci_-6 alkoxyl, substituted Ci_-6 alkoxyl, acyl, substituted acyl, Ci_-6 aminoalkyl or substituted Ci_-6 aminoalkyl. In some embodiments, R^1*, R², R³, R⁵, R^5* are hydrogen. In some embodiments, R^1*, R², R³ are hydrogen and one or both of R⁵, R^5* may be other than hydrogen as referred to above and in WO 2007/134181 or WO2009/067647 (alpha-L-bicyclic nucleic acids analogs).

In some embodiments the LNA used in the oligonucleotide compounds of the invention eneral formula II:

wherein Y is selected from the group consisting of -0-, -CH₂0-, -S-, -NH-, N(R^e) and/or - CH₂-; Z and Z* are independently selected among an internucleotide linkage, R^H, a terminal group or a protecting group; B constitutes a natural or non-natural nucleotide base moiety (nucleobase), and R^H is selected from hydrogen and Ci_-4-alkyl; R^a, R^b R^c, R^d and R^e are, optionally independently, selected from the group consisting of hydrogen, optionally substituted Ci-i₂-alkyl, optionally substituted C_2-i₂-alkenyl, optionally substituted C_2-i₂-alkynyl, hydroxy, Ci-i₂-alkoxy, C_2-i₂-alkoxyalkyl, C_2-i₂-alkenyloxy, carboxy, Ci-i₂-alkoxycarbonyl, CM₂- alkylcarbonyl, formyl, aryl, aryloxy-carbonyl, aryloxy, arylcarbonyl, heteroaryl, heteroaryloxy- carbonyl, heteroaryloxy, heteroarylcarbonyl, amino, mono- and di(Ci_-6-alkyl)amino, carbamoyl, mono- and di(Ci_-6-alkyl)-amino-carbonyl, amino-Ci_-6-alkyl-aminocarbonyl, mono- and di(Ci-6-alkyl)amino-Ci-6-alkyl-aminocarbonyl, Ci_-6-alkyl-carbonylamino, carbamido, Ci_-6- alkanoyloxy, sulphono, Ci_-6-alkylsulphonyloxy, nitro, azido, sulphanyl, Ci_-6-alkylthio, halogen, DNA intercalators, photochemically active groups, thermochemically active groups, chelating groups, reporter groups, and ligands, where aryl and heteroaryl may be optionally substituted and where two geminal substituents R^a and R^b together may designate optionally substituted methylene (=CH₂); and R^H is selected from hydrogen and Ci_-4-alkyl. In some embodiments R^a, R^b R^c, R^d and R^e are, optionally independently, selected from the group consisting of hydrogen and Ci_₆ alkyl, such as methyl. For all chiral centers, asymmetric groups may be found in either R or S orientation, for example, two exemplary stereochemical isomers include the beta-D and alpha-L isoforms, which may be illustrated as follows:

Specific exemplary LNA units are shown below:

β-D-oxy-LNA

β-D-thio-LNA

β-D-ENA

β-D-amino-LNA

The term "thio-LNA" comprises a locked nucleotide in which Y in the general formula above is selected from S or -CH₂-S-. Thio-LNA can be in both beta-D and alpha-L- configuration.

The term "amino-LNA" comprises a locked nucleotide in which Y in the general formula above is selected from -N(H)-, N(R)-, CH₂-N(H)-, and -CH₂-N(R)- where R is selected from hydrogen and Ci_-4-alkyl. Amino-LNA can be in both beta-D and alpha-L-configuration.

The term "oxy-LNA" comprises a locked nucleotide in which Y in the general formula above represents -0-. Oxy-LNA can be in both beta-D and alpha-L-configuration.

The term "ENA" comprises a locked nucleotide in which Y in the general formula above is -CH₂-0- (where the oxygen atom of -CH₂-0- is attached to the 2'-position relative to the base B). R^e is hydrogen or methyl.

In some exemplary embodiments LNA is selected from beta-D-oxy-LNA, alpha-L-oxy-LNA, beta-D-amino-LNA and beta-D-thio-LNA, in particular beta-D-oxy-LNA.

RNAse recruitment

It is recognised that an oligomeric compound may function via non RNase mediated degradation of target mRNA, such as by steric hindrance of translation, or other methods, however, the preferred oligomers of the invention are capable of recruiting an

endoribonuclease (RNase), such as RNase H.

It is preferable that the oligomer, or contiguous nucleotide sequence, comprises of a region of at least 6, such as at least 7 consecutive nucleotide units, such as at least 8 or at least 9 consecutive nucleotide units (residues), including 7, 8, 9, 10, 1 1 , 12, 13, 14, 15 or 16 consecutive nucleotides, which, when formed in a duplex with the complementary target RNA is capable of recruiting RNase. The contiguous sequence which is capable of recruiting RNAse may be region B as referred to in the context of a gapmer as described herein. In some embodiments the size of the contiguous sequence which is capable of recruiting

RNAse, such as region B, may be higher, such as 10, 1 1 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 nucleotide units.

EP 1 222 309 provides in vitro methods for determining RNaseH activity, which may be used to determine the ability to recruit RNaseH. A oligomer is deemed capable of recruiting RNase H if, when provided with the complementary RNA target, it has an initial rate, as measured in pmol/l/min, of at least 1 %, such as at least 5%, such as at least 10% or ,more than 20% of the of the initial rate determined using DNA only oligonucleotide, having the same base sequence but containing only DNA monomers, with no 2' substitutions, with phosphorothioate linkage groups between all monomers in the oligonucleotide,, using the methodology provided by Example 91 - 95 of EP 1 222 309.

In some embodiments, an oligomer is deemed essentially incapable of recruiting RNaseH if, when provided with the complementary RNA target, and RNaseH, the RNaseH initial rate, as measured in pmol/l/min, is less than 1 %, such as less than 5%, such as less than 10% or less than 20% of the initial rate determined using the equivalent DNA only oligonucleotide, with no 2' substitutions, with phosphorothioate linkage groups between all nucleotides in the oligonucleotide, using the methodology provided by Example 91 - 95 of EP 1 222 309.

In other embodiments, an oligomer is deemed capable of recruiting RNaseH if, when provided with the complementary RNA target, and RNaseH, the RNaseH initial rate, as measured in pmol/l/min, is at least 20%, such as at least 40 %, such as at least 60 %, such as at least 80 % of the initial rate determined using the equivalent DNA only oligonucleotide, with no 2' substitutions, with phosphorothioate linkage groups between all nucleotides in the oligonucleotide, using the methodology provided by Example 91 - 95 of EP 1 222 309.

Typically the region of the oligomer which forms the consecutive nucleotide units which, when formed in a duplex with the complementary target RNA is capable of recruiting RNase consists of nucleotide units which form a DNA/RNA like duplex with the RNA target - and include both DNA units and LNA units which are in the alpha-L configuration, particularly preferred being alpha-L-oxy LNA.

The oligomer of the invention may comprise a nucleotide sequence which comprises both nucleotides and nucleotide analogues, and may be in the form of a gapmer, a headmer or a mixmer.

A "headmer" is defined as an oligomer that comprises a region X and a region Y that is contiguous thereto, with the 5'-most monomer of region Y linked to the 3'-most monomer of region X. Region X comprises a contiguous stretch of non-RNase recruiting nucleoside analogues and region Y comprises a contiguous stretch (such as at least 7 contiguous monomers) of DNA monomers or nucleoside analogue monomers recognizable and cleavable by the RNase.

A "tailmer" is defined as an oligomer that comprises a region X and a region Y that is contiguous thereto, with the 5'-most monomer of region Y linked to the 3'-most monomer of the region X. Region X comprises a contiguous stretch (such as at least 7 contiguous monomers) of DNA monomers or nucleoside analogue monomers recognizable and cleavable by the RNase, and region X comprises a contiguous stretch of non-RNase recruiting nucleoside analogues.

Other "chimeric" oligomers, called "mixmers", consist of an alternating composition of (i) DNA monomers or nucleoside analogue monomers recognizable and cleavable by RNase, and (ii) non-RNase recruiting nucleoside analogue monomers.

In some embodiments, in addition to enhancing affinity of the oligomer for the target region, some nucleoside analogues also mediate RNase (e.g., RNaseH) binding and cleavage. Since a-L-LNA monomers recruit RNaseH activity to a certain extent, in some embodiments, gap regions (e.g., region B as referred to herein) of oligomers containing a-L- LNA monomers consist of fewer monomers recognizable and cleavable by the RNaseH, and more flexibility in the mixmer construction is introduced.

Gapmer Design

Preferably, the oligomer of the invention is a gapmer. A gapmer oligomer is an oligomer which comprises a contiguous stretch of nucleotides which is capable of recruiting an RNAse, such as RNAseH, such as a region of at least 6 or 7 DNA nucleotides, referred to herein in as region B (B), wherein region B is flanked both 5' and 3' by regions of affinity enhancing nucleotide analogues, such as from 1 - 6 nucleotide analogues 5' and 3' to the contiguous stretch of nucleotides which is capable of recruiting RNAse - these regions are referred to as regions A (A) and C (C) respectively.

In some embodiments, the monomers which are capable of recruiting RNAse are selected from the group consisting of DNA monomers, alpha-L-LNA monomers, C4' alkylayted DNA monomers (see PCT/EP2009/050349 and Vester ef a/., Bioorg. Med. Chem. Lett. 18 (2008) 2296 - 2300, hereby incorporated by reference), and UNA (unlinked nucleic acid) nucleotides (see Flutter ef a/., Mol. Biosyst., 2009, 10, 1039 hereby incorporated by reference). UNA is unlocked nucleic acid, typically where the C2 - C3 C-C bond of the ribose has been removed, forming an unlocked "sugar" residue. Preferably the gapmer comprises a (poly)nucleotide sequence of formula (5' to 3'), A-B-C, or optionally A-B-C-D or D-A-B-C, wherein; region A (A) (5' region) consists or comprises of at least one nucleotide analogue, such as at least one LNA unit, such as from 1-6 nucleotide analogues, such as LNA units, and; region B (B) consists or comprises of at least five consecutive nucleotides which are capable of recruiting RNAse (when formed in a duplex with a complementary RNA molecule, such as the mRNA target), such as DNA nucleotides, and; region C (C) (3'region) consists or comprises of at least one nucleotide analogue, such as at least one LNA unit, such as from 1-6 nucleotide analogues, such as LNA units, and; region D (D), when present consists or comprises of 1 , 2 or 3 nucleotide units, such as DNA nucleotides. In some embodiments, region A consists of 1 , 2, 3, 4, 5 or 6 nucleotide analogues, such as LNA units, such as from 2-5 nucleotide analogues, such as 2-5 LNA units, such as 3 or 4 nucleotide analogues, such as 3 or 4 LNA units; and/or region C consists of 1 , 2, 3, 4, 5 or 6 nucleotide analogues, such as LNA units, such as from 2-5 nucleotide analogues, such as 2-5 LNA units, such as 3 or 4 nucleotide analogues, such as 3 or 4 LNA units.

In some embodiments B consists or comprises of 5, 6, 7, 8, 9, 10, 11 or 12 consecutive nucleotides which are capable of recruiting RNAse, or from 6-10, or from 7-9, such as 8 consecutive nucleotides which are capable of recruiting RNAse. In some embodiments region B consists or comprises at least one DNA nucleotide unit, such as 1-12 DNA units, preferably from 4-12 DNA units, more preferably from 6-10 DNA units, such as from 7-10 DNA units, most preferably 8, 9 or 10 DNA units.

In some embodiments region A consist of 3 or 4 nucleotide analogues, such as LNA, region B consists of 7, 8, 9 or 10 DNA units, and region C consists of 3 or 4 nucleotide analogues, such as LNA. Such designs include (A-B-C) 3-10-3, 3-10-4, 4-10-3, 3-9-3, 3-9-4, 4-9-3, 3-8-3, 3-8-4, 4-8-3, 3-7-3, 3-7-4, 4-7-3, and may further include region D, which may have one or 2 nucleotide units, such as DNA units.

Further gapmer designs are disclosed in WO2004/046160, which is hereby

incorporated by reference. WO2008/1 13832, which claims priority from US provisional application 60/977,409 hereby incorporated by reference, refers to 'shortmer' gapmer oligomers. In some embodiments, oligomers presented here may be such shortmer gapmers.

In some embodiments the oligomer is consisting of a contiguous nucleotide sequence of a total of 10, 1 1 , 12, 13 or 14 nucleotide units, wherein the contiguous nucleotide sequence is of formula (5' - 3'), A-B-C, or optionally A-B-C-D or D-A-B-C, wherein; A consists of 1 , 2 or 3 nucleotide analogue units, such as LNA units; B consists of 7, 8 or 9 contiguous nucleotide units which are capable of recruiting RNAse when formed in a duplex with a complementary RNA molecule (such as a mRNA target); and C consists of 1 , 2 or 3 nucleotide analogue units, such as LNA units. When present, D consists of a single DNA unit.

In some embodiments A consists of 1 LNA unit. In some embodiments A consists of 2

LNA units. In some embodiments A consists of 3 LNA units. In some embodiments C consists of 1 LNA unit. In some embodiments C consists of 2 LNA units. In some embodiments C consists of 3 LNA units. In some embodiments B consists of 7 nucleotide units. In some embodiments B consists of 8 nucleotide units. In some embodiments B consists of 9 nucleotide units. In certain embodiments, region B consists of 10 nucleoside monomers. In certain embodiments, region B comprises 1 - 10 DNA monomers. In some embodiments B comprises of from 1 to about 9 DNA units, such as 2, 3, 4, 5, 6, 7 , 8 or 9 DNA units. In some embodiments B consists of DNA units. In some embodiments B comprises of at least one LNA unit which is in the alpha-L configuration, such as 2, 3, 4, 5, 6, 7, 8 or 9 LNA units in the alpha-L-configuration. In some embodiments B comprises of at least one alpha-L-oxy LNA unit or wherein all the LNA units in the alpha-L- configuration are alpha-L-oxy LNA units. In some embodiments the number of nucleotides present in A-B-C are selected from the group consisting of (nucleotide analogue units - region B - nucleotide analogue units): 1-8-1 , 1-8-2, 2-8-1 , 2-8-2, 3-8-3, 2-8-3, 3-8-2, 4-8-1 , 4-8-2, 1-8-4, 2-8-4, or; 1-9-1 , 1-9-2, 2-9-1 , 2-9-2, 2-9-3, 3-9-2, 1-9-3, 3-9-1 , 4-9-1 , 1-9-4, or; 1-10-1 , 1-10-2, 2-10- 1 , 2-10-2, 1-10-3, 3-10-1. In some embodiments the number of nucleotides in A-B-C are selected from the group consisting of: 2-7-1 , 1-7-2, 2-7-2, 3-7-3, 2-7-3, 3-7-2, 3-7-4, and 4-7- 3. In certain embodiments, each of regions A and C consists of three LNA monomers, and region B consists of 8 or 9 or 10 nucleoside monomers, preferably DNA monomers. In some embodiments both A and C consists of two LNA units each, and B consists of 8 or 9 nucleotide units, preferably DNA units. In various embodiments, other gapmer designs include those where regions A and/or C consists of 3, 4, 5 or 6 nucleoside analogues, such as monomers containing a 2'-0-methoxyethyl-ribose sugar (2'-MOE) or monomers containing a 2'-fluoro-deoxyribose sugar, and region B consists of 8, 9, 10, 1 1 or 12 nucleosides, such as DNA monomers, where regions A-B-C have 3-9-3, 3-10-3, 5-10-5 or 4- 12-4 monomers. Further gapmer designs are disclosed in WO 2007/14651 1A2, hereby incorporated by reference.

Internucleotide Linkages

The monomers of the oligomers described herein are coupled together via linkage groups. Suitably, each monomer is linked to the 3' adjacent monomer via a linkage group.

The person having ordinary skill in the art would understand that, in the context of the present invention, the 5' monomer at the end of an oligomer does not comprise a 5' linkage group, although it may or may not comprise a 5' terminal group.

The terms "linkage group" or "internucleotide linkage" are intended to mean a group capable of covalently coupling together two nucleotides. Specific and preferred examples include phosphate groups and phosphorothioate groups.

The nucleotides of the oligomer of the invention or contiguous nucleotides sequence thereof are coupled together via linkage groups. Suitably each nucleotide is linked to the 3' adjacent nucleotide via a linkage group.

Suitable internucleotide linkages include those listed within WO2007/031091 , for example the internucleotide linkages listed on the first paragraph of page 34 of

WO2007/031091 (hereby incorporated by reference). It is, in some embodiments, preferred to modify the internucleotide linkage from its normal phosphodiester to one that is more resistant to nuclease attack, such as

phosphorothioate or boranophosphate - these two, being cleavable by RNase H, also allow that route of antisense inhibition in reducing the expression of the target gene.

Suitable sulphur (S) containing internucleotide linkages as provided herein may be preferred. Phosphorothioate internucleotide linkages are also preferred, particularly for the gap region (B) of gapmers. Phosphorothioate linkages may also be used for the flanking regions (A and C, and for linking A or C to D, and within region D, as appropriate).

Regions A, B and C, may however comprise internucleotide linkages other than phosphorothioate, such as phosphodiester linkages, particularly, for instance when the use of nucleotide analogues protects the internucleotide linkages within regions A and C from endo-nuclease degradation - such as when regions A and C comprise LNA nucleotides.

The internucleotide linkages in the oligomer may be phosphodiester, phosphorothioate or boranophosphate so as to allow RNase H cleavage of targeted RNA. Phosphorothioate is preferred, for improved nuclease resistance and other reasons, such as ease of

manufacture.

In one aspect of the oligomer of the invention, the nucleotides and/or nucleotide analogues are linked to each other by means of phosphorothioate groups.

It is recognised that the inclusion of phosphodiester linkages, such as one or two linkages, into an otherwise phosphorothioate oligomer, particularly between or adjacent to nucleotide analogue units (typically in region A and or C) can modify the bioavailability and/or bio-distribution of an oligomer - see WO2008/053314, hereby incorporated by reference.

In some embodiments, such as the embodiments referred to above, where suitable and not specifically indicated, all remaining linkage groups are either phosphodiester or phosphorothioate, or a mixture thereof.

In some embodiments all the internucleotide linkage groups are phosphorothioate.

When referring to specific gapmer oligonucleotide sequences, such as those provided herein it will be understood that, in various embodiments, when the linkages are phosphorothioate linkages, alternative linkages, such as those disclosed herein may be used, for example phosphate (phosphodiester) linkages may be used, particularly for linkages between nucleotide analogues, such as LNA, units. Likewise, when referring to specific gapmer oligonucleotide sequences, such as those provided herein, when the C residues are annotated as 5'methyl modified cytosine, in various embodiments, one or more of the Cs present in the oligomer may be unmodified C residues. Oligomeric Compounds

The oligomers of the invention may, for example, have a sequence selected from the group consisting of SEQ ID NOs 1-19 as shown in Table 1 , or a sequence which is a subset of one of SEQ ID NOs 1-19.

Conjugates

In the context of this disclosure, the term "conjugate" is intended to indicate a heterogenous molecule formed by the covalent attachment ("conjugation") of the oligomer as described herein to one or more non-nucleotide, or non-polynucleotide moieties. Examples of non-nucleotide or non- polynucleotide moieties include macromolecular agents such as proteins, fatty acid chains, sugar residues, glycoproteins, polymers, or combinations thereof. Typically proteins may be antibodies for a target protein. Typical polymers may be

polyethylene glycol.

Therefore, in various embodiments, the oligomer of the invention may comprise both a polynucleotide region which typically consists of a contiguous sequence of nucleotides, and a further non-nucleotide region. When referring to the oligomer of the invention consisting of a contiguous nucleotide sequence, the compound may comprise non-nucleotide components, such as a conjugate component.

In various embodiments of the invention the oligomeric compound is linked to ligands/conjugates, which may be used, e.g. to increase the cellular uptake of oligomeric compounds. WO2007/031091 provides suitable ligands and conjugates, which are hereby incorporated by reference.

The invention also provides for a conjugate comprising the compound according to the invention as herein described, and at least one non-nucleotide or non-polynucleotide moiety covalently attached to said compound. Therefore, in various embodiments where the compound of the invention consists of a specified nucleic acid or nucleotide sequence, as herein disclosed, the compound may also comprise at least one non-nucleotide or non- polynucleotide moiety (e.g. not comprising one or more nucleotides or nucleotide analogues) covalently attached to said compound.

Conjugation (to a conjugate moiety) may enhance the activity, cellular distribution or cellular uptake of the oligomer of the invention. Such moieties include, but are not limited to, antibodies, polypeptides, lipid moieties such as a cholesterol moiety, cholic acid, a thioether, e.g. Hexyl-s-tritylthiol, a thiocholesterol, an aliphatic chain, e.g., dodecandiol or undecyl residues, a phospholipids, e.g., di-hexadecyl-rac-glycerol or triethylammonium 1 ,2-di-o- hexadecyl-rac-glycero-3-h-phosphonate, a polyamine or a polyethylene glycol chain, an adamantane acetic acid, a palmityl moiety, an octadecylamine or hexylamino-carbonyl- oxycholesterol moiety. The oligomers of the invention may also be conjugated to active drug substances, for example, aspirin, ibuprofen, a sulfa drug, an antidiabetic, an antibacterial or an antibiotic.

In certain embodiments the conjugated moiety is a sterol, such as cholesterol.

In various embodiments, the conjugated moiety comprises or consists of a positively charged polymer, such as a positively charged peptides of, for example from 1 -50, such as 2 - 20 such as 3 - 10 amino acid residues in length, and/or polyalkylene oxide such as polyethylglycol(PEG) or polypropylene glycol - see WO 2008/034123, hereby incorporated by reference. Suitably the positively charged polymer, such as a polyalkylene oxide may be attached to the oligomer of the invention via a linker such as the releasable inker described in WO 2008/034123.

By way of example, the following conjugate moieties may be used in the conjugates of the invention: 5'- OLIGOMER -3'

5'- OLIGOMER -3'

Activated oligomers

The term "activated oligomer," as used herein, refers to an oligomer of the invention that is covalently linked (i.e., functionalized) to at least one functional moiety that permits covalent linkage of the oligomer to one or more conjugated moieties, i.e., moieties that are not themselves nucleic acids or monomers, to form the conjugates herein described.

Typically, a functional moiety will comprise a chemical group that is capable of covalently bonding to the oligomer via, e.g., a 3'-hydroxyl group or the exocyclic NH₂ group of the adenine base, a spacer that is preferably hydrophilic and a terminal group that is capable of binding to a conjugated moiety (e.g., an amino, sulfhydryl or hydroxyl group). In some embodiments, this terminal group is not protected, e.g., is an NH₂ group. In other embodiments, the terminal group is protected, for example, by any suitable protecting group such as those described in "Protective Groups in Organic Synthesis" by Theodora W Greene and Peter G M Wuts, 3rd edition (John Wiley & Sons, 1999). Examples of suitable hydroxyl protecting groups include esters such as acetate ester, aralkyl groups such as benzyl, diphenylmethyl, or triphenylmethyl, and tetrahydropyranyl. Examples of suitable amino protecting groups include benzyl, alpha-methylbenzyl, diphenylmethyl, triphenylmethyl, benzyloxycarbonyl, tert-butoxycarbonyl, and acyl groups such as trichloroacetyl or trifluoroacetyl. In some embodiments, the functional moiety is self-cleaving. In other embodiments, the functional moiety is biodegradable. See e.g., U.S. Patent No. 7,087,229, which is incorporated by reference herein in its entirety.

In some embodiments, oligomers of the invention are functionalized at the 5' end in order to allow covalent attachment of the conjugated moiety to the 5' end of the oligomer. In other embodiments, oligomers of the invention can be functionalized at the 3' end. In still other embodiments, oligomers of the invention can be functionalized along the backbone or on the heterocyclic base moiety. In yet other embodiments, oligomers of the invention can be functionalized at more than one position independently selected from the 5' end, the 3' end, the backbone and the base.

In some embodiments, activated oligomers of the invention are synthesized by incorporating during the synthesis one or more monomers that is covalently attached to a functional moiety. In other embodiments, activated oligomers of the invention are

synthesized with monomers that have not been functionalized, and the oligomer is functionalized upon completion of synthesis. In some embodiments, the oligomers are functionalized with a hindered ester containing an aminoalkyi linker, wherein the alkyl portion has the formula (CH₂)_W, wherein w is an integer ranging from 1 to 10, preferably about 6, wherein the alkyl portion of the alkylamino group can be straight chain or branched chain, and wherein the functional group is attached to the oligomer via an ester group (-O-C(O)- (CH₂)_WNH).

In other embodiments, the oligomers are functionalized with a hindered ester containing a (CH₂)_w-sulfhydryl (SH) linker, wherein w is an integer ranging from 1 to 10, preferably about 6, wherein the alkyl portion of the alkylamino group can be straight chain or branched chain, and wherein the functional group attached to the oligomer via an ester group (-0-C(0)-(CH₂)_wSH)

In some embodiments, sulfhydryl-activated oligonucleotides are conjugated with polymer moieties such as polyethylene glycol or peptides (via formation of a disulfide bond).

Activated oligomers containing hindered esters as described above can be synthesized by any method known in the art, and in particular by methods disclosed in PCT Publication No. WO 2008/034122 and the examples therein, which is incorporated herein by reference in its entirety.

In still other embodiments, the oligomers of the invention are functionalized by introducing sulfhydryl, amino or hydroxyl groups into the oligomer by means of a

functionalizing reagent substantially as described in U.S. Patent Nos. 4,962,029 and

4,914,210, i.e., a substantially linear reagent having a phosphoramidite at one end linked through a hydrophilic spacer chain to the opposing end which comprises a protected or unprotected sulfhydryl, amino or hydroxyl group. Such reagents primarily react with hydroxyl groups of the oligomer. In some embodiments, such activated oligomers have a

functionalizing reagent coupled to a 5'-hydroxyl group of the oligomer. In other

embodiments, the activated oligomers have a functionalizing reagent coupled to a 3'- hydroxyl group. In still other embodiments, the activated oligomers of the invention have a functionalizing reagent coupled to a hydroxyl group on the backbone of the oligomer. In yet further embodiments, the oligomer of the invention is functionalized with more than one of the functionalizing reagents as described in U.S. Patent Nos. 4,962,029 and 4,914,210, incorporated herein by reference in their entirety. Methods of synthesizing such

functionalizing reagents and incorporating them into monomers or oligomers are disclosed in U.S. Patent Nos. 4,962,029 and 4,914,210.

In some embodiments, the 5'-terminus of a solid-phase bound oligomer is

functionalized with a dienyl phosphoramidite derivative, followed by conjugation of the deprotected oligomer with, e.g., an amino acid or peptide via a Diels-Alder cycloaddition reaction.

In various embodiments, the incorporation of monomers containing 2'-sugar modifications, such as a 2'-carbamate substituted sugar or a 2'-(0-pentyl-N-phthalimido)- deoxyribose sugar into the oligomer facilitates covalent attachment of conjugated moieties to the sugars of the oligomer. In other embodiments, an oligomer with an amino-containing linker at the 2'-position of one or more monomers is prepared using a reagent such as, for example, 5'-dimethoxytrityl-2'-0-(e-phthalimidylaminopentyl)-2'-deoxyadenosine-3'- N,N- diisopropyl-cyanoethoxy phosphoramidite. See, e.g., Manoharan, et al., Tetrahedron Letters, 1991 , 34, 7171.

In still further embodiments, the oligomers of the invention may have amine-containing functional moieties on the nucleobase, including on the N6 purine amino groups, on the exocyclic N2 of guanine, or on the N4 or 5 positions of cytosine. In various embodiments, such functionalization may be achieved by using a commercial reagent that is already functionalized in the oligomer synthesis.

Some functional moieties are commercially available, for example, heterobifunctional and homobifunctional linking moieties are available from the Pierce Co. (Rockford, III.).

Other commercially available linking groups are 5'-Amino-Modifier C6 and 3'-Amino-Modifier reagents, both available from Glen Research Corporation (Sterling, Va.). 5'-Amino-Modifier C6 is also available from ABI (Applied Biosystems Inc., Foster City, Calif.) as Aminolink-2, and 3'-Amino-Modifier is also available from Clontech Laboratories Inc. (Palo Alto, Calif.). Compositions

The oligomer of the invention may be used in pharmaceutical formulations and compositions. Suitably, such compositions comprise a pharmaceutically acceptable diluent, carrier, salt or adjuvant. WO/2007/031091 provides suitable and preferred pharmaceutically acceptable diluent, carrier and adjuvants - which are hereby incorporated by reference. Suitable dosages, formulations, administration routes, compositions, dosage forms, combinations with other therapeutic agents, pro-drug formulations are also provided in WO/2007/031091- which is hereby incorporated by reference.

Applications

The oligomers of the invention may be utilized as research reagents for, for example, diagnostics, therapeutics and prophylaxis.

In research, such oligomers may be used to specifically inhibit the synthesis of aurora kinase B protein (typically by degrading or inhibiting the mRNA and thereby prevent protein formation) in cells and experimental animals thereby facilitating functional analysis of the target or an appraisal of its usefulness as a target for therapeutic intervention.

In diagnostics the oligomers may be used to detect and quantitate aurora kinase B expression in cell and tissues by northern blotting, in-situ hybridisation or similar techniques.

For therapeutics, an animal or a human, suspected of having a disease or disorder, which can be treated by modulating the expression of aurora kinase B is treated by administering oligomeric compounds in accordance with this invention. Further provided are methods of treating a mammal, such as treating a human, suspected of having or being prone to a disease or condition, associated with expression of aurora kinase B by administering a therapeutically or prophylactically effective amount of one or more of the oligomers or compositions of the invention. The oligomer, a conjugate or a pharmaceutical composition according to the invention is typically administered in an effective amount.

The invention also provides for the use of the compound or conjugate of the invention as described for the manufacture of a medicament for the treatment of a disorder as referred to herein, or for a method of the treatment of as a disorder as referred to herein.

The invention also provides for a method for treating a disorder as referred to herein said method comprising administering a compound according to the invention as herein described, and/or a conjugate according to the invention, and/or a pharmaceutical composition according to the invention to a patient in need thereof.

Medical Indications

The oligomers and other compositions according to the invention can be used for the treatment of conditions associated with over expression or expression of mutated version of the aurora kinase B. The invention further provides use of a compound of the invention in the manufacture of a medicament for the treatment of a disease, disorder or condition as referred to herein.

Generally stated, one aspect of the invention is directed to a method of treating a mammal suffering from or susceptible to conditions associated with abnormal levels of aurora kinase B, comprising administering to the mammal and therapeutically effective amount of an oligomer targeted to aurora kinase B that comprises one or more LNA units. The oligomer, a conjugate or a pharmaceutical composition according to the invention is typically administered in an effective amount.

The disease or disorder, as referred to herein, may, in some embodiments, be associated with a mutation in the aurora kinase B gene or a gene whose protein product is associated with or interacts with aurora kinase B. Therefore, in some embodiments, the target mRNA is a mutated form of the aurora kinase B sequence.

An interesting aspect of the invention is directed to the use of an oligomer (compound) as defined herein or a conjugate as defined herein for the preparation of a medicament for the treatment of a disease, disorder or condition as referred to herein.

The methods of the invention are preferably employed for treatment or prophylaxis against diseases caused by abnormal levels of aurora kinase B.

Alternatively stated, In some embodiments, the invention is furthermore directed to a method for treating abnormal levels of aurora kinase B, said method comprising

administering a oligomer of the invention, or a conjugate of the invention or a pharmaceutical composition of the invention to a patient in need thereof.

The invention also relates to an oligomer, a composition or a conjugate as defined herein for use as a medicament.

The invention further relates to use of a compound, composition, or a conjugate as defined herein for the manufacture of a medicament for the treatment of abnormal levels of aurora kinase B or expression of mutant forms of aurora kinase B (such as allelic variants, such as those associated with one of the diseases referred to herein).

Moreover, the invention relates to a method of treating a subject suffering from a disease or condition such as those referred to herein.

A patient who is in need of treatment is a patient suffering from or likely to suffer from the disease or disorder.

In some embodiments, the term 'treatment' as used herein refers to both treatment of an existing disease (e.g. a disease or disorder as herein referred to), or prevention of a disease, i.e. prophylaxis. It will therefore be recognised that treatment as referred to herein may, in some embodiments, be prophylactic. EMBODIMENTS

The following embodiments of the present invention may be used in combination with the other embodiments described herein.

1. An oligomer of from 10 to 30 nucleotides in length which comprises a contiguous

nucleotide sequence of a total of from 10 to 30 nucleotides, wherein said contiguous nucleotide sequence is at least 80% homologous to a region corresponding to a mammalian aurora kinase B gene or the reverse complement of an mRNA, such as NM_004217 or naturally occurring variant thereof.

2. The oligomer according to embodiment 1 , wherein the contiguous nucleotide sequence is at least 80% homologous to a region corresponding to any of SEQ ID NO: 1-19.

3. The oligomer according to embodiment 1 or 2, wherein the contiguous nucleotide

sequence comprises no mismatches or no more than one or two mismatches with the reverse complement of the corresponding region of any one of SEQ ID NO: 1-19.

4. The oligomer according to any one of embodiments 1 - 3, wherein the nucleotide

sequence of the oligomer consists of the contiguous nucleotide sequence.

5. The oligomer according to any one of embodiments 1 - 4, wherein the contiguous

nucleotide sequence is from 10 to 18 nucleotides in length.

6. The oligomer according to any one of embodiments 1 - 5, wherein the contiguous

nucleotide sequence comprises nucleotide analogues.

7. The oligomer according to embodiment 6, wherein the nucleotide analogues are sugar modified nucleotides, such as sugar modified nucleotides selected from the group consisting of: Locked Nucleic Acid (LNA) units; 2'-0-alkyl-RNA units, 2'-OMe-RNA units, 2'-amino-DNA units, and 2'-fluoro-DNA units.

8. The oligomer according to embodiment 6, wherein the nucleotide analogues are LNA. 9. The oligomer according to any one of embodiments 6 - 8 which is a gapmer.

10. The oligomer according to any one of embodiments 1 - 9, which inhibits the expression of aurora kinase B gene or mRNA in a cell which is expressing aurora kinase B gene or mRNA.

1 1. A conjugate comprising the oligomer according to any one of embodiments 1 - 10, and at least one non-nucleotide or non-polynucleotide moiety covalently attached to said oligomer.

12. A pharmaceutical composition comprising the oligomer according to any one of

embodiments 1 - 10, or the conjugate according to embodiment 11 , and a

pharmaceutically acceptable diluent, carrier, salt or adjuvant.

13. The oligomer according to any one of embodiments 1 - 10, or the conjugate according to embodiment 1 1 , for use as a medicament, such as for the treatment of cancer. 14. The use of an oligomer according to any one of the embodiments 1-10, or a conjugate as defined in embodiment 11 , for the manufacture of a medicament for the treatment of cancer.

15. A method of treating cancer, said method comprising administering an effective amount of an oligomer according to any one of the embodiments 1-10, or a conjugate according to embodiment 1 1 , or a pharmaceutical composition according to embodiment 12, to a patient suffering from, or likely to suffer from cancer.

16. A method for the inhibition of aurora kinase B in a cell which is expressing aurora kinase B, said method comprising administering an oligomer according to any one of the embodiments 1-10, or a conjugate according to embodiment 11 to said cell so as to inhibit aurora kinase B in said cell.

17. An oligomer according to any one of the previous embodiments, wherein the oligomer is capable of down-regulating AurkB mRNA in HEI_A cells by at least 80%, such as at least 81 %, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91 %, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or such at least 100%, when the oligo is transfected into HELA cells by naked delivery as described in Example 4 at a concentration of 25 μΜ

18. An oligomer according to any one of the previous embodiments, wherein the oligomer is for use in combination with another active ingredient, en example in combination with another drug for cancer treatment, or in combination with radiation therapy

19. An oligomer according to embodiment 18, wherein the oligomer is formulated together with the other active ingredient.

20. An oligomer according to embodiment 18, wherein the oligomer and the other active ingredient are in separate formulations.

21. An oligomer according to any one of embodiments 18-20, wherein the oligomer is for use with more than one other active ingredient, and/or radiation therapy.

EXAMPLES

Example 1: Design of the oligonucleotides

In accordance with the present invention, a series of different oligonucleotides were designed to target different regions of human AurkB (GenBank accession number

NM_004217). These are shown in Table 1. In Table 1 , SEQ ID NOs:1-19 are oligonucleotide sequences designed to target human AurkB. In SEQ ID NOs: 1-19, upper case letters indicate nucleotide analogue units, such as LNA or Beta-D-oxy LNA, and subscript "s" represents phosphorothioate linkage. Lower case letters represent nucleotide units, such as DNA units. Absence of "s" (if any) indicates phosphodiester linkage. Nucleotide analogue cytosines are preferably 5-methylcytosine.SEQ ID NOs: 21-39 represent the unmodified sequences of SEQ ID NOs: 1-19. SEQ ID NO: 20 represent the human AurkB mRNA (GenBank accession number NM_004217), all of SEQ ID NOs: 1-19 and 21-39 are antisense to SEQ ID NO: 20. Table 1 : Antisense oligonucleotide sequences of the invention

Target

Length site in

SEQ ID NO Sequence (5'-3')

(bases) NM 004

217*

SEQ ID NO: 1 ^Gs^Gs^Ts9s^as^cs^as9s9s^cs^ts^cs^ts^Ts^Ts^C 16 151 -166

SEQ ID NO: 2 ^As^Gs^Gs^as^cs^as^as^gs^ts^gs^cs^as^gs^As^Ts^G 16 168-183

SEQ ID NO: 3 ^cs^Gs^cs^cs^cs^as^as^ts^cs^ts^cs^as^as^As^Gs^T 16 288-303

SEQ ID NO: 4 ^Ts^Ts^Gs^cs^cs^ts^ts^ts9s^cs^cs^cs^as^Gs^As^G 16 306-321

SEQ ID NO: 5 Vs^Gs^cs^cs^cs^as^gs^as^gs^gs^as^cs^Gs^Cs^C 16 300-315

SEQ ID NO: 6 ^Cs^Cs^Cs9s^as9s^cs^cs^as^as9s^ts^as^Cs^As^C 16 332-347

SEQ ID NO: 7 ^Gs^As^Cs^ts^ts9s^as^as9s^as9s9s^as^Cs^Cs^T 16 378-393

SEQ ID NO: 8 ^Ts^As^Gs^as^as^ts^cs^as^as9s^ts^as9s^As^Ts^c 16 508-523

SEQ ID NO: 9 ^Ts^Gs^cs^cs^as^as^cs^ts^cs^cs^ts^cs^cs^As^Ts^G 16 601 -616

SEQ ID NO:

10 ^Gs^Gs^cs^ts^ts^ts^as^tsgs^ts^cs^ts^cs^Ts^Gs^T 16 654-669

SEQ ID NO:

1 1 ^As^Gs^cs^cs^cs^ts^as^as^gs^as^gs^cs^as^Gs^As^T 16 675-690

SEQ ID NO:

12 ^Gs^Ts^cs^as^gs^cs^as^as^ts^cs^ts^ts^cs^As^Gs^c 16 700-715

SEQ ID NO:

13 ^cs^As^Ts^gs^cs^as^cs^as^gs^as^cs^cs^as^Gs^cs^c 16 719-734

SEQ ID NO:

14 ^cs^cs^Ts^cs^as^as^ts^cs^as^ts^cs^ts^cs^Ts^Gs^G 16 785-800

SEQ ID NO:

15 ^cs^Ts^cs^cs^as^as^ts^gs^cs^as^cs^cs^as^cs^As^G 16 827-842

SEQ ID NO:

16 ^Ts^cs^As^ts^as^gs^cs^as^as^as^gs^cs^as^cs^Ts^c 16 840-855

SEQ ID NO:

17 ^Gs^Gs^As^as^cs^ts^ts^ts^as^gs^gs^ts^cs^cs^As^c 16 923-938

SEQ ID NO:

18 ^Gs^Gs^Ts^ts^as^ts^gs^cs^cs^ts^gs^as^gs^cs^As^G 16 980-995

SEQ ID NO: 1056- 19 ^Gs^Gs^As^gs^gs^cs^as^gs^cs^as^cs^cs^cs^Ts^cs^c 16

1071

GGGCGGCCGG GAGAGTAGCA GTGCCTTGGA CCCCAGCTCT CCTCCCCCTT TCTCTCTAAG GATGGCCCAG AAGGAGAACT CCTACCCCTG GCCCTACGGC CGACAGACGG CTCCATCTGG

SEQ ID NO:

20 CCTGAGCACC CTGCCCCAGC GAGTCCTCCG GAAAGAGCCT 1 -1253

GTCACCCCAT CTGCACTTGT CCTCATGAGC CGCTCCAATG TCCAGCCCAC AGCTGCCCCT GGCCAGAAGG TGATGGAGAA TAGCAGTGGG ACACCCGACA TCTTAACGCG GCACTTCACA Target

Length site in

SEQ ID NO Sequence (5'-3')

(bases) NM 004

217*

ATTGATGACT TTGAGATTGG GCGTCCTCTG GGCAAAGGCA

AGTTTGGAAA CGTGTACTTG GCTCGGGAGA AGAAAAGCCA

TTTCATCGTG GCGCTCAAGG TCCTCTTCAA GTCCCAGATA

GAGAAGGAGG GCGTGGAGCA TCAGCTGCGC AGAGAGATCG

AAATCCAGGC CCACCTGCAC CATCCCAACA TCCTGCGTCT

CTACAACTAT TTTTATGACC GGAGGAGGAT CTACTTGATT

CTAGAGTATG CCCCCCGCGG GGAGCTCTAC AAGGAGCTGC

AGAAGAGCTG CACATTTGAC GAGCAGCGAA CAGCCACGAT

CATGGAGGAG TTGGCAGATG CTCTAATGTA CTGCCATGGG

AAGAAGGTGA TTCACAGAGA CATAAAGCCA GAAAATCTGC

TCTTAGGGCT CAAGGGAGAG CTGAAGATTG CTGACTTCGG

CTGGTCTGTG CATGCGCCCT CCCTGAGGAG GAAGACAATG

TGTGGCACCC TGGACTACCT GCCCCCAGAG ATGATTGAGG

GGCGCATGCA CAATGAGAAG GTGGATCTGT GGTGCATTGG

AGTGCTTTGC TATGAGCTGC TGGTGGGGAA CCCACCCTTT

GAGAGTGCAT CACACAACGA GACCTATCGC CGCATCGTCA

AGGTGGACCT AAAGTTCCCC GCTTCCGTGC CCATGGGAGC

CCAGGACCTC ATCTCCAAAC TGCTCAGGCA TAACCCCTCG

GAACGGCTGC CCCTGGCCCA GGTCTCAGCC CACCCTTGGG

TCCGGGCCAA CTCTCGGAGG GTGCTGCCTC CCTCTGCCCT

TCAATCTGTC GCCTGATGGT CCCTGTCATT CACTCGGGTG

CGTGTGTTTG TATGTCTGTG TATGTATAGG GGAAAGAAGG

GATCCCTAAC TGTTCCCTTA TCTGTTTTCT ACCTCCTCCT

TTGTTTAATA AAGGCTGAAG CTTTTTGTAC TCATGAAAAA

AAAAAAAAAA AAA

SEQ ID NO:

GGTGACAGGCTC I M C 16 151 -166 21

SEQ ID NO:

AGGACAAGTGCAGATG 16 168-183 22

SEQ ID NO:

CGCCCAATCTCAAAGT 16 288-303 23

SEQ ID NO:

TTGCC I I I GCCCAGAG 16 306-321 24

SEQ ID NO:

TTGCCCAGAGGACGCC 16 300-315 25

SEQ ID NO:

CCCGAGCCAAGTACAC 16 332-347 26

SEQ ID NO:

GACTTGAAGAGGACCT 16 378-393 27

SEQ ID NO:

TAGAATCAAGTAGATC 16 508-523 28

SEQ ID NO:

TGCCAACTCCTCCATG 16 601 -616 29

SEQ ID NO:

GGC I I I ATGTCTCTGT 16 654-669 30 Target

Length site in

SEQ ID NO Sequence (5'-3')

(bases) NM 004

217*

SEQ ID NO:

AGCCCTAAGAGCAGAT 16 675-690

31

SEQ ID NO:

GTC AG C AATCTTC AG C 16 700-715

32

SEQ ID NO:

CATGCACAGACCAGCC 16 719-734

33

SEQ ID NO:

CCTCAATCATCTCTGG 16 785-800

34

SEQ ID NO:

CTCCAATGCACCACAG 16 827-842

35

SEQ ID NO:

TC ATAG C AAAG C ACTC 16 840-855

36

SEQ ID NO:

GGAAC I I I AGGTCCAC 16 923-938

37

SEQ ID NO:

GGTTATGCCTGAGCAG 16 980-995

38

SEQ ID NO: 1056-

GGAGGCAGCACCCTCC 16

39 1071

The exempli ied AurKB target nucleic acid sequence, GenBank accession number

NM_004217, is herein incorporated in its entirety as SEQ ID NO: 20.

Example 2: In vitro model: Cell culture

The effect of antisense oligonucleotides on target nucleic acid expression can be tested in any of a variety of cell types provided that the target nucleic acid is present at measurable levels. The target can be expressed endogenously or by transient or stable transfection of a nucleic acid encoding said target. The expression level of target nucleic acid can be routinely determined using, for example, Northern blot analysis, Real-Time PCR, ribonuclease protection assays. The following cell types are provided for illustrative purposes, but other cell types can be routinely used, provided that the target is expressed in the cell type chosen.

Cells were cultured in the appropriate medium as described below and maintained at 37°C at 95-98% humidity and 5% C0₂. Cells were routinely passaged 2-3 times weekly.

HeLa: The human cervix adenocarcinoma cell line HeLa was cultured in Minimum Essential Medium Eagle (EMEM, Sigma) + 10% fetal bovine serum (FBS) + 2 mM Glutamax I + IxNEAA + gentamicin (25μg/ml).

Example 3: In vitro model: Treatment with antisense oligonucleotide using lipid transfection

The HeLa cell line described in example 2 was treated with oligonucleotide using the cationic liposome formulation LipofectAMINE 2000 (Gibco) as transfection vehicle. Cells were seeded in 6-well cell culture plates (NUNC) and treated when 80-90% confluent. Oligo concentrations used ranged from 1 nM to 5 nM final concentration. Formulation of oligo-lipid complexes were carried out essentially as described by the manufacturer using serum-free OptiMEM (Gibco) and a final lipid concentration of 2.5 μg/mL LipofectAMINE 2000. Cells were incubated at 37°C for 4 hours and treatment was stopped by removal of oligo- containing culture medium. Cells were washed and serum-containing media was added. After oligo treatment cells were allowed to recover for 20 hours before they were harvested for RNA analysis. Example 4: In vitro model: Natural uptake of antisense oligonucleotide

The HeLa cell line listed in example 2 was incubated with oligonucleotide dissolved in sterile water without any transfection vehicle. Cells were seeded in 24-well cell culture plates (NUNC) and incubated with oligonucleotide when 10-30% confluent. Oligonucleotide concentrations used ranged from 1 μΜ to 25μΜ, final concentration. Cells were incubated at 37°C in the oligonucleotide-containing normal growth serum for 2 days before they were harvested for RNA analysis.

Example 5: In vitro model: Extraction of RNA and cDNA synthesis

Total RNA Isolation and First strand synthesis

Total RNA was extracted from cells transfected as described above and using the

Qiagen RNeasy kit (Qiagen cat. no. 74104) according to the manufacturer's instructions. First strand synthesis was performed using Reverse Transcriptase reagents from Ambion according to the manufacturer's instructions.

For each sample 0.25-0.5 μg total RNA was adjusted to (10.8 μΙ) with RNase free H₂0 and mixed with 2 μΙ random decamers (50 μΜ) and 4 μΙ dNTP mix (2.5 mM each dNTP) and heated to 70 °C for 3 min after which the samples were rapidly cooled on ice. After cooling the samples on ice, 2 μΙ 10x Buffer RT, 1 μΙ MMLV Reverse Transcriptase (100 U/μΙ) and 0.25 μΙ RNase inhibitor (10 U/μΙ) was added to each sample, followed by incubation at 42 °C for 60 min, heat inactivation of the enzyme at 95°C for 10 min and then the sample was cooled to 4 °C.

Example 6: In vitro model: Analysis of Oligonucleotide Inhibition of AurkB Expression by Real-time PCR

Antisense modulation of AurkB expression can be assayed in a variety of ways known in the art. For example, AurkB mRNA levels can be quantitated by, e.g., Northern blot analysis, competitive polymerase chain reaction (PCR), or real-time PCR. Real-time quantitative PCR is presently preferred. RNA analysis can be performed on total cellular RNA or mRNA.

Methods of RNA isolation and RNA analysis such as Northern blot analysis is routine in the art and is taught in, for example, Current Protocols in Molecular Biology, John Wiley and Sons.

Real-time quantitative (PCR) can be conveniently accomplished using the commercially available Multi-Color Real Time PCR Detection System, available from Applied Biosystems.

Real-time Quantitative PCR Analysis of AurkB mRNA Levels

The sample content of human AurkB mRNA was quantified using the human AurkB

ABI Prism Pre-Developed TaqMan Assay Reagents (Applied Biosystems cat. no.

Hs00177782_m1 according to the manufacturer's instructions.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA quantity was used as an endogenous control for normalizing any variance in sample preparation.

The sample content of human GAPDH mRNA was quantified using the human GAPDH

ABI Prism Pre-Developed TaqMan Assay Reagent (Applied Biosystems cat. no. 4310884E) according to the manufacturer's instructions.

Real-time Quantitative PCR is a technique well known in the art and is taught in for example Heid et al. Real time quantitative PCR, Genome Research (1996), 6: 986-994.

Real time PCR: The cDNA from the first strand synthesis performed as described in example 5 was diluted 2-20 times, and analyzed by real time quantitative PCR using Taqman 7500 FAST or 7900 FAST from Applied Biosystems. The primers and probe were mixed with 2 x Taqman Fast Universal PCR master mix (2x) (Applied Biosystems Cat.# 4364103) and added to 4 μΙ cDNA to a final volume of 10 μΙ. Each sample was analysed in duplicate.

Assaying 2 fold dilutions of a cDNA that had been prepared on material purified from a cell line expressing the RNA of interest generated standard curves for the assays. Sterile H₂0 was used instead of cDNA for the no template control. PCR program: 60° C for 2 minutes, then 95° C for 30 seconds, followed by 40 cycles of 95° C, 3 seconds, 60° C, 20-30 seconds. Relative quantities of target mRNA sequence were determined from the calculated Threshold cycle using the Applied Biosystems Fast System SDS Software Version 1.3.1.21. or SDS Software Version 2.3.

Example 7: In vitro analysis: Antisense Inhibition of Human AurkB Expression by oligonucleotide compounds Oligonucleotides presented in Table 1 were evaluated in the HeLa cell line for their potential to knock down AurkB expression at concentrations of 1 and 5 nM using lipid transfection (see Figure 1 and Table 2). Table 2: Antisense Inhibition of Human AurkB expression by oligonucleotides- lipid transfection.

The data in Table 2 are presented as percentage down-regulation relative to mock transfected cells at 5 nM in the Hela cells. Lower case letters represent DNA units, bold upper case letters represent LNA, preferably β-D-oxy-LNA units. All LNA C are preferably 5'methyl C. Subscript "s" represents phosphorothioate linkage.

Percent inhibition of

Test

Sequence (5"-3') AurkB in HeLa cells at 5 substance

nM

SEQ ID NO: 1 ^Gs^Gs^Ts9s^as^cs^as9s9s^cs^ts^cs^ts^Ts^Ts^C 97

SEQ ID NO: 2 ^As^Gs^Gs^as^cs^as^as9s^ts9s^cs^as9s^As^Ts^G 99

SEQ ID NO: 3 ^s^Gs^s^cs^cs^as^as^ts^cs^ts^cs^as^as^As^Gs^ 76

SEQ ID NO: 4 ^Ts^Ts^Gs^cs^cs^ts^ts^ts9_s ^cs^cs^cs^as^Gs^As^G 93

SEQ ID NO: 5 ^Ts^Ts^Gs^cs^cs^cs^as9_s ^as9_s9s^as^cs^Gs^Cs^C 92

SEQ ID NO: 6 ^s^s^s9s^as9s^cs^cs^as^as9s^ts^as^s^As^ 94

SEQ ID NO: 7 ^Gs^As^Cs^ts^ts9s^as^as9s^as9s9_s ^as^Cs^Cs^T 86

SEQ ID NO: 8 T_s ^As^Gs^as^as^ts^cs^as^as9s^ts^as9s^As^s^ 80

SEQ ID NO: 9 T_s ^Gs^s^cs^as^as^cs^ts^cs^cs^ts^cs^cs^As^s^G 82

SEQ ID NO: 10 ^Gs^Gs^cs^ts^ts^ts^as^ts9_s ^ts^cs^ts^cs^Ts^Gs^T 96

SEQ ID NO: 11 ^As^Gs^s^cs^cs^ts^as^as9s^as9s^cs^as^Gs^As^ 87

SEQ ID NO: 12 ^Gs^s^s^as9s^cs^as^as^ts^cs^ts^ts^cs^As^Gs^ 92

SEQ ID NO: 13 ^s^As^s9s^cs^as^cs^as9s^as^cs^cs^as^Gs^s^ 79

SEQ ID NO: 14 ^s^s^s^cs^as^as^ts^cs^as^ts^cs^ts^cs^s^Gs^G 76

SEQ ID NO: 15 ^s^s^s^cs^as^as^ts9s^cs^as^cs^cs^as^s^As^G 88

SEQ ID NO: 16 T_s^s^As^ts^as9s^cs^as^as^as9s^cs^as^s^s^ 94

SEQ ID NO: 17 ^Gs^Gs^As^as^cs^ts^ts^ts^as9s9s^ts^cs^s^As^ 81

SEQ ID NO: 18 ^Gs^Gs^Ts^ts^as^ts9s^cs^cs^ts9_s ^as9s^Cs^As^G 95

SEQ ID NO: 19 ^Gs^Gs^As9_s9s^cs^as9_s ^cs^as^cs^cs^cs^Ts^Cs^C 40 As shown in Table 2, oligonucleotides of SEQ ID NOs: 1 , 2, 4, 5, 6, 10, 12, 16, and 18 demonstrated about 90% or greater inhibition of AurkB expression in these experiments and are therefore preferred.

Also preferred are oligonucleotides based on the illustrated antisense oligo sequences, for example varying the length (shorter or longer) and/or nucleobase content (e.g. the type and/or proportion of analogue units), which also provide good inhibition of AurkB expression

Example 8: In vitro analysis: Antisense Inhibition of Human AurkB Expression by oligonucleotide compounds

Oligonucleotides presented in Table 1 were evaluated in the HeLa cell line for their potential to knockdown of AurkB at concentrations of 1 , 5 and 25 μΜ using natural uptake without any transfection vehicle (see Figure 2 and Table 3).

Table 3: Antisense Inhibition of Human AurkB expression by oligonucleotides- natural transfection

The data in Table 3 are presented as percentage down-regulation relative to mock treated cells at 25μΜ in the HeLa cells. Lower case letters represent DNA units, bold upper case letters represent, LNA preferably β-D-oxy-LNA units. All LNA C are preferably 5'methyl C. Subscript "s" represents phosphorothioate linkage.

As shown in Table 3, oligonucleotides of SEQ ID NOs: 1 , 2, 4, 6, 10, 12, 16, and 18 demonstrated about 80% or greater inhibition of AurkB expression in these experiments and are therefore preferred.

Also preferred are oligonucleotides based on the illustrated antisense oligo sequences, for example varying the length (shorter or longer) and/or nucleobase content (e.g. the type and/or proportion of analogue units), which also provide good inhibition of AurkB expression. Example 9: In vivo screen of antisense oligonucleotides

The antisense oligonucleotides of the invention will optionally be tested in vivo in an animal model which suits the sequence of the individual oligo, at a dose of 25mg/kg every second day for a total of 4 doses. The animals will be dosed with 10 ml per kg body weight i.v. of the antisense oligonucleotide compounds formulated in the vehicle or vehicle alone. Liver and spleen tissue will be harvested 24 hours after the last dose for RNA analysis. The sample content of murine AurkB mRNA will be quantified using the murine AurkB ABI Prism Pre-Developed TaqMan Assay Reagents (Applied Biosystems cat. no. Mm01718140_m1) according to the manufacturer's instructions.

The sample content of murine GAPDH mRNA will be quantified using the murine GAPDH ABI Prism Pre-Developed TaqMan Assay Reagents (Applied Biosystems cat. no. 435239E) according to the manufacturer's instructions.

Claims

1. An oligomer of from 10 to 30 nucleotides in length which comprises a contiguous nucleotide sequence of a total of from 10 to 30 nucleotides, wherein said contiguous nucleotide sequence is at least 80% homologous to a region corresponding to a mammalian aurora kinase B gene or the reverse complement of an mRNA, such as

NM_004217 or naturally occurring variant thereof.

2. The oligomer according to claim 1 , wherein the contiguous nucleotide sequence is at least 80% homologous to a region corresponding to any of SEQ ID NO: 21-39.

3. The oligomer according to claim 1 or 2, wherein the contiguous nucleotide sequence comprises no mismatches or no more than one or two mismatches with the reverse complement of the corresponding region of any one of SEQ ID NO: 21-39.

4. The oligomer according to any one of claims 1 - 3, wherein the nucleotide sequence of the oligomer consists of the contiguous nucleotide sequence.

5. The oligomer according to any one of claims 1 - 4, wherein the contiguous nucleotide sequence is from 10 to 18 nucleotides in length.

6. The oligomer according to any one of claims 1 - 5, wherein the contiguous nucleotide sequence comprises nucleotide analogues.

7. The oligomer according to claim 6, wherein the nucleotide analogues are sugar

modified nucleotides, such as sugar modified nucleotides selected from the group consisting of: Locked Nucleic Acid (LNA) units; 2'-0-alkyl-RNA units, 2'-OMe-RNA units, 2'-amino-DNA units, and 2'-fluoro-DNA units.

8. The oligomer according to claim 6, wherein the nucleotide analogues are LNA.

9. The oligomer according to any one of claims 6 - 8 which is a gapmer.

10. The oligomer according to any one of claims 1-9, wherein the oligomer is any one of SEQ ID NOs: 1-19.

1 1. The oligomer according to any one of claims 1 - 10, which inhibits the expression of aurora kinase B gene or mRNA in a cell which is expressing aurora kinase B gene or mRNA.

12. A conjugate comprising the oligomer according to any one of claims 1 - 1 1 , and at least one non-nucleotide or non-polynucleotide moiety covalently attached to said oligomer.

13. A pharmaceutical composition comprising the oligomer according to any one of claims 1 - 11 , or the conjugate according to claim 12, and a pharmaceutically acceptable diluent, carrier, salt or adjuvant.

14. The oligomer according to any one of claims 1 - 11 , or the conjugate according to claim 12, for use as a medicament, such as for the treatment of cancer.

15. The use of an oligomer according to any one of the claims 1-1 1 , or a conjugate as defined in claim 12, for the manufacture of a medicament for the treatment of cancer.

16. A method of treating cancer, said method comprising administering an effective

amount of an oligomer according to any one of the claims 1-11 , or a conjugate according to claim 12, or a pharmaceutical composition according to claim 13, to a patient suffering from, or likely to suffer from cancer.

17. A method for the inhibition of aurora kinase B in a cell which is expressing aurora kinase B, said method comprising administering an oligomer according to any one of the claims 1-1 1 , or a conjugate according to claim 12 to said cell so as to inhibit aurora kinase B in said cell.