Oligonucleotide analogs having cationic intersubunit linkages

• US 7,943,762 B2
• Filed: 05/10/2007
• Issued: 05/17/2011
• Est. Priority Date: 05/10/2006
• Status: Active Grant

• Current Assignee: Avi Biopharma, Inc.
• Original Assignee: Avi Biopharma, Inc.
• Inventors: Hassinger, Jed N., Cai, Bao Zhong, Weller, Dwight D.
• Primary Examiner(s): ZARA, JANE J
• Application Number:
  US11/801,885
• Publication Number:
  US 20090088562A1
• Time in Patent Office: 1,468 Days
• Field of Search: 435/6, 435/91.1, 435/91.31, 536/23.1, 536/24.5, 536/31
• US Class Current: 536/31
• CPC Class Codes: C07H 21/00 Compounds containing two or more mononucleotide units having separate phosphate or polyphosphate groups linked by saccharide radicals of nucleoside groups, e.g. nucleic acids
• CPC Class Codes: C12N 15/111 General methods applicable to biologically active non-coding nucleic acids
• CPC Class Codes: C12N 15/1131 against viruses
• CPC Class Codes: C12N 15/1132 against retroviridae, e.g. HIV
• CPC Class Codes: C12N 15/1135 against oncogenes or tumor suppressor genes
• CPC Class Codes: C12N 15/1137 against enzymes viral enzymes C12N15/1131; receptors C12N15/1138
• CPC Class Codes: C12N 15/1138 against receptors or cell surface proteins
• CPC Class Codes: C12N 2310/3145 with the nitrogen in 3' or 5'-position
• CPC Class Codes: C12N 2310/3233 Morpholino-type ring
• CPC Class Codes: C12N 2310/351 Conjugate
• CPC Class Codes: C12N 2310/3513 Protein; Peptide
• CPC Class Codes: C12N 2320/51 modulating the chemical stability, e.g. nuclease-resistance
• CPC Class Codes: C12N 2330/30 chemically synthesised

Abstract

Morpholino oligomers containing both uncharged and cationic intersubunit linkages are provided. The oligomers are oligonucleotide analogs containing predetermined sequences of base-pairing moieties. The presence of the cationic intersubunit linkages in the oligomers, typically at a level of about 10-50% of total linkages, provides enhanced antisense activity, in various antisense applications, relative to the corresponding uncharged oligomers. Also provided are such oligomers conjugated to peptide transporter moieties, where the transporters are preferably composed of arginine subunits, or arginine dimers, alternating with neutral amino acid subunits.

Claims

1. An oligomer comprising a sequence of morpholino subunits, each morpholino subunit comprising a base-pairing moiety, such that the oligomer can bind in a sequence-specific manner to a target nucleic acid, wherein the morpholino subunits are each joined by a phosphorus-containing intersubunit linkage having the structure:

2. The oligomer of claim 1, wherein each of the morpholino subunits have the structure (i):

3. The oligomer of claim 1, wherein each linkage (b1) in the oligomer has the same W, X and Y groups.

4. The oligomer of claim 1, wherein 5% to 50% of the intersubunit linkages in the oligomer are linkage (b1).

5. The oligomer of claim 4, wherein 10% to 35% of the intersubunit linkages in the oligomer are linkage (b1).

6. The oligomer of claim 1, wherein for each occurrence of linkage (a), X is NR¹R², and each of R¹ and R² is methyl.

7. The oligomer of claim 1, wherein the oligomer comprises at least two consecutive intersubunit linkages of linkage (a).

8. The oligomer of claim 1 having a length of 10 to 40 subunits.

9. The oligomer of claim 1 having a length of 15 to 25 subunits.

10. The oligomer of claim 1, wherein each R is H, R⁴ is H, CH₃ or an electron pair, and R³ is H, CH₃, —

C(═

NH)NH₂ or —

C(O)-L-NHC(═

NH)NH₂.

11. The oligomer of claim 1, wherein each R is H, R³ is H or CH₃ and R⁴ is an electron pair, H or CH₃.

12. The oligomer of claim 11, wherein each of R³ and R⁴ is H, and linkage (b1) has the following structure (iv):

13. The oligomer of claim 1, wherein each of W and Y are O.

14. The oligomer of claim 11, wherein R³ is H, R⁴ is an electron pair and linkage (b1) has the following structure (v):

15. The oligomer of claim 14, wherein each of W and Y are O.

16. The oligomer of claim 1, wherein Z is a direct bond and L has the structure —

(CH₂)_n—

where n is 1-12.