EP2658579A2 - Conjugués d'administration de polynucléotide in vivo ayant des liaisons sensibles à des enzymes - Google Patents

Conjugués d'administration de polynucléotide in vivo ayant des liaisons sensibles à des enzymes

Info

Publication number
EP2658579A2
EP2658579A2 EP11853858.6A EP11853858A EP2658579A2 EP 2658579 A2 EP2658579 A2 EP 2658579A2 EP 11853858 A EP11853858 A EP 11853858A EP 2658579 A2 EP2658579 A2 EP 2658579A2
Authority
EP
European Patent Office
Prior art keywords
polymer
mmol
product
polynucleotide
delivery
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP11853858.6A
Other languages
German (de)
English (en)
Other versions
EP2658579A4 (fr
Inventor
David B. Rozema
David L. Lewis
Darren H. Wakefield
Eric A. Kitas
Philipp Hadwiger
Jon A. Wolff
Ingo Roehl
Peter Mohr
Torsten Hoffmann
Kerstin Jahn-Hofmann
Hans Martin Mueller
Guenther Ott
Andrei V. Blokhin
Jeffrey C. Carlson
Jonathan D. Benson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Arrowhead Pharmaceuticals Inc
Original Assignee
Arrowhead Research Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US13/336,028 external-priority patent/US8426554B2/en
Application filed by Arrowhead Research Corp filed Critical Arrowhead Research Corp
Publication of EP2658579A2 publication Critical patent/EP2658579A2/fr
Publication of EP2658579A4 publication Critical patent/EP2658579A4/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C233/00—Carboxylic acid amides
    • C07C233/01—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms
    • C07C233/02—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having nitrogen atoms of carboxamide groups bound to hydrogen atoms or to carbon atoms of unsubstituted hydrocarbon radicals
    • C07C233/04—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having nitrogen atoms of carboxamide groups bound to hydrogen atoms or to carbon atoms of unsubstituted hydrocarbon radicals with carbon atoms of carboxamide groups bound to acyclic carbon atoms of an acyclic saturated carbon skeleton
    • C07C233/05—Carboxylic acid amides having carbon atoms of carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms having nitrogen atoms of carboxamide groups bound to hydrogen atoms or to carbon atoms of unsubstituted hydrocarbon radicals with carbon atoms of carboxamide groups bound to acyclic carbon atoms of an acyclic saturated carbon skeleton having the nitrogen atoms of the carboxamide groups bound to hydrogen atoms or to acyclic carbon atoms
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/56—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule
    • A61K47/58—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. poly[meth]acrylate, polyacrylamide, polystyrene, polyvinylpyrrolidone, polyvinylalcohol or polystyrene sulfonic acid resin
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/56—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule
    • A61K47/59—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyureas or polyurethanes
    • A61K47/60—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an organic macromolecular compound, e.g. an oligomeric, polymeric or dendrimeric molecule obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyureas or polyurethanes the organic macromolecular compound being a polyoxyalkylene oligomer, polymer or dendrimer, e.g. PEG, PPG, PEO or polyglycerol
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K48/00—Medicinal preparations containing genetic material which is inserted into cells of the living body to treat genetic diseases; Gene therapy
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P1/00—Drugs for disorders of the alimentary tract or the digestive system
    • A61P1/16—Drugs for disorders of the alimentary tract or the digestive system for liver or gallbladder disorders, e.g. hepatoprotective agents, cholagogues, litholytics
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
    • C07C69/96—Esters of carbonic or haloformic acids
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K5/00—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof
    • C07K5/04—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof containing only normal peptide links
    • C07K5/06—Dipeptides
    • C07K5/06104—Dipeptides with the first amino acid being acidic
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K5/00—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof
    • C07K5/04—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof containing only normal peptide links
    • C07K5/06—Dipeptides
    • C07K5/06104—Dipeptides with the first amino acid being acidic
    • C07K5/06113—Asp- or Asn-amino acid
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/91—Polymers modified by chemical after-treatment
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00—Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09—Recombinant DNA-technology
    • C12N15/87—Introduction of foreign genetic material using processes not otherwise provided for, e.g. co-transformation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K5/00—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof
    • C07K5/04—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof containing only normal peptide links
    • C07K5/06—Dipeptides
    • C07K5/06008—Dipeptides with the first amino acid being neutral
    • C07K5/06017—Dipeptides with the first amino acid being neutral and aliphatic
    • C07K5/06034—Dipeptides with the first amino acid being neutral and aliphatic the side chain containing 2 to 4 carbon atoms
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K5/00—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof
    • C07K5/04—Peptides containing up to four amino acids in a fully defined sequence; Derivatives thereof containing only normal peptide links
    • C07K5/06—Dipeptides
    • C07K5/06008—Dipeptides with the first amino acid being neutral
    • C07K5/06078—Dipeptides with the first amino acid being neutral and aromatic or cycloaliphatic
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00—Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09—Recombinant DNA-technology
    • C12N15/11—DNA or RNA fragments; Modified forms thereof; Non-coding nucleic acids having a biological activity
    • C12N15/111—General methods applicable to biologically active non-coding nucleic acids
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2310/00—Structure or type of the nucleic acid
    • C12N2310/10—Type of nucleic acid
    • C12N2310/14—Type of nucleic acid interfering N.A.
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2310/00—Structure or type of the nucleic acid
    • C12N2310/30—Chemical structure
    • C12N2310/35—Nature of the modification
    • C12N2310/351—Conjugate
    • C12N2310/3513—Protein; Peptide
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2320/00—Applications; Uses
    • C12N2320/30—Special therapeutic applications
    • C12N2320/32—Special delivery means, e.g. tissue-specific
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2800/00—Nucleic acids vectors
    • C12N2800/95—Protection of vectors from inactivation by agents such as antibodies or enzymes, e.g. using polymers
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2810/00—Vectors comprising a targeting moiety
    • C12N2810/10—Vectors comprising a non-peptidic targeting moiety

Definitions

  • polynucleotide and other substantially cell membrane impermeable compounds into a living cell is highly restricted by the complex membrane system of the cell.
  • Drugs used in antisense, RNAi, and gene therapies are relatively large hydrophilic polymers and are frequently highly negatively charged. Both of these physical characteristics severely restrict their direct diffusion across the cell membrane. For this reason, the major barrier to polynucleotide delivery is the delivery of the polynucleotide across a cell membrane to the cell cytoplasm or nucleus.
  • nucleic acid dose required with these methods has been prohibitively large.
  • transfection reagents have also been developed that achieve reasonably efficient delivery of polynucleotides to cells in vitro.
  • in vivo delivery of polynucleotides using these same transfection reagents is complicated and rendered ineffective by in vivo toxicity, adverse serum interactions, and poor targeting.
  • Transfection reagents that work well in vitro, cationic polymers and lipids typically form large cationic electrostatic particles and destabilize cell membranes.
  • the positive charge of in vitro transfection reagents facilitates association with nucleic acid via charge-charge (electrostatic) interactions thus forming the nucleic acid/transfection reagent complex.
  • Positive charge is also beneficial for nonspecific binding of the vehicle to the cell and for membrane fusion, destabilization, or disruption.
  • Destabilization of membranes facilitates delivery of the substantially cell membrane impermeable polynucleotide across a cell membrane. While these properties facilitate nucleic acid transfer in vitro, they cause toxicity and ineffective targeting in vivo.
  • Cationic charge results in interaction with serum components, which causes destabilization of the polynucleotide-transfection reagent interaction, poor bioavailability, and poor targeting.
  • Membrane activity of transfection reagents which can be effective in vitro, often leads to toxicity in vivo.
  • the vehicle should be small, less than 1 00 nm in diameter, and preferably less than 50 nm. Even smaller complexes, less that 20 nm or less than 10 nm would be more useful yet. Delivery vehicles larger than 1 00 nm have very little access to cells other than blood vessel cells in vivo. Complexes formed by electrostatic interactions tend to aggregate or fall apart when exposed to physiological salt concentrations or serum components. Further, cationic charge on in vivo delivery vehicles leads to adverse serum interactions and therefore poor bioavailability. Interestingly, high negative charge can also inhibit targeted in vivo delivery by interfering with interactions necessary for targeting, i.e. binding of targeting ligands to cellular receptors. Thus, near neutral vehicles are desired for in vivo distribution and targeting. Without careful regulation, membrane disruption or destabilization activities are toxic when used in vivo. Balancing vehicle toxicity with nucleic acid delivery is more easily attained in vitro than in vivo.
  • Rozema et al. in U.S. Patent Publication 200801 5266 1 , provided a means to reversibly regulate membrane disruptive activity of a membrane active polyamine using disubstituted maleic anhydride modification.
  • Maleamate linkages formed by reaction of a ma!eic anhydride with an amine are pH labile in a pH range suitable for in vivo delivery. This process allowed membrane active polymers to be used for in vivo delivery or nucleic acid.
  • dipeptide masking agents for reversibly modifying and inhibiting membrane activity of an amphipathic membrane active polyamine comprising: a steric stabilizer or targeting ligand attached to a dipeptide-amidobenzyl-carbonate, referred to herein as dipeptide masking agents or protease cleavable masking agents.
  • the dipeptide masking agents have the general form:
  • R is a steric stabilizer or targeting ligand
  • a 1 is an amino acid
  • a 2 is an amino acid.
  • Reaction of the masking agent carbonate with a polymer amine yields a carbamate linkage.
  • the masking agent is stable until the dipeptide is cleaved in vivo by an endogenous protease, thus cleaving the steric stabilizer or targeting ligand from the polyamine.
  • the amidobenzyl- carbamate undergoes a spontaneous rearrangement which results in regeneration of the polymer amine.
  • R is neutral. More preferably, R is uncharged.
  • a preferred steric stabilizer is a polyethylene glycol (PEG).
  • a targeting ligand may be selected from the list comprising haptens such as digoxigenin, vitamin such as biotin, antibody, monoclonal antibody, and cell surface receptor ligand.
  • a targeting ligand may be linked to the dipeptide via a linker such as a PEG linker.
  • a preferred cell surface receptor ligand is an asialoglycoprotein receptor (ASGPr) ligand.
  • a preferred ASGPR ligand is an N- Acetylgalactosamine (NAG).
  • a preferred dipeptide consists of a hydrophobic amino acid linked to a hydrophilic uncharged amino acid via an amide bond.
  • a preferred amidobenzyl group is a p-amidobenzyl group.
  • a preferred carbonate is an activated amine reactive carbonate.
  • the invention features a composition for delivering an RNA interference (RNAi) polynucleotide to a cell in vivo comprising: a masked amphipathic membrane active polyamine (delivery polymer) wherein the polyamine is masked by reversible modification with the dipeptide masking agents described herein and an RNAi polynucleotide.
  • the delivery polymer can be covalently linked to the RNAi polynucleotide.
  • a preferred linkage for covalent attachment of the delivery polymer to the RNAi polynucleotide is a physiologically labile linkage. In one embodiment, this linkage is orthogonal to the dipeptide masking agent linkage.
  • the delivery polymer is not covalently linked to the RNAi polynucleotide and the RNAi polynucleotide is covalently linked to a targeting molecule.
  • composition comprising: an amphipathic membrane active polyamine covalently linked to: a) a plurality of targeting ligands or steric stabilizers via dipeptide-amidobenzyl-carbamate linkages; and, b) one or more polynucleotides via one or more reversible linkages.
  • dipeptide- amidobenzyl-carbamate linkage is orthogonal to the polynucleotide reversible covalent linkage.
  • the polynucleotide-polymer conjugate is administered to a mammal in a pharmaceutically acceptable carrier or diluent.
  • composition comprising: a) an amphipathic membrane active polyamine covalently linked to a plurality of targeting ligands or steric stabilizers via dipeptide-amidobenzyl-carbamate linkages; and, b) an RNAi polynucleotide covalently linked to a targeting group selected from the list consisting of: a hydrophobic group having 20 or more carbons atoms and a galactose cluster.
  • the RNAi polynucleotide is not covalently linked to the modified amphipathic membrane active polyamine.
  • the modified polyamine and the RNAi polynucleotide targeting group conjugate are synthesized separately and may be supplied in separate containers or a single container.
  • the modified polyamine and RNAi polynucleotide-targeting group conjugate are administered together or separately to a mammal in pharmaceutically acceptable carriers or diluents.
  • a preferred dipeptide masking agent comprises a protease (peptidase) cleavable dipeptide-p- amidobenzyl amine-reactive carbonate derivative.
  • Protease cleavable masking agents of the invention employ a dipeptide connected to an amidobenzyl activated carbonate moiety.
  • a targeting ligand or steric stabilizer is attached to the amino terminus of a dipeptide.
  • the amidobenzyl activated carbonate moiety is attached at the carboxy terminus of the dipeptide.
  • Protease cleavable linkers suitable for use with the invention have the general structure:
  • R4 comprises a targeting ligand or steric stabilizer
  • R3 comprises an amine reactive carbonate moiety
  • R l and R2 are amino acid side chains.
  • a preferred activated carbonate is a para-nitrophenol.
  • other amine reactive carbonates known in the art are readily substituted for the para-nitrophenol. Reaction of the activated carbonate with an amine connects the targeting ligand or steric stabilizer to the membrane active polyamine via a peptidase cleavable dipeptide-amidobenzyl carbamate linkage. Enzyme cleavage of the dipeptide, between the amino acid and the amidobenzyl group removes R4 from the polymer and triggers an elim ination reaction which results in regeneration of the polymer amine.
  • the dipeptide masking agents of the invention are useful for reversible modification/inhibition of amphipathic membrane active polyamines.
  • a covalent bond is created by the reaction of the activated carbonate of the dipeptide masking agent with a polymer amine, particularly a primary amine, group.
  • a conjugate comprising the dipeptide-amidobenzyl-carbonate masking agent described herein and an amphipathic membrane active polyamine:
  • FIG. 1 Illustration showing the structure of a dipeptide masking agent wherein:
  • R I and R2 are the R groups of amino acids
  • R4 is a targeting ligand of a steric stabilizer
  • X is -NH-, -0-, or -CH2-
  • Y is -NH- or -O-
  • R5 is at position 2, 4, or 6 and is -CH2-0-C(0)-0-Z wherein Z carbonate, and R6 is independently hydrogen, alkyl, or halide at each of positions 2, 3, 4, 5, or 6 except for the position occupied by R5.
  • FIG. 2 Illustration showing the structure of a dipeptide masking agent linked to a polyamine wherein: Rl and R2 are the R groups of amino acids, R4 is a targeting ligand of a steric stabilizer, X is - H-, -0-, or -CH 2 - and Y is -NH- or -0-.
  • FIG. 4. Graph illustrating circulation times of polymers modified with a dipeptide masking agent vs. two different maleic anhydride based masking agents.
  • the peptidase cleavable linkages are stable to hydrolysis in absence of enzyme, electrically neutral and provide extended DPC stability in storage and in in vivo circulation. Improved (longer) half-life in circulation facilitates widening of the window of opportunity for ligand-mediated accumulation in tissue, such as tumor tissue.
  • the delivery polymers are particularly useful for in vivo delivery of RNAi polynucleotides. In vivo delivery of RNAi polynucleotides is useful for therapeutic inhibition (knockdown) of gene expression.
  • the dipeptide masking agents have the general form:
  • R is a steric stabilizer or targeting ligand
  • a 1 is an amino acid
  • a 2 is an amino acid
  • carbonate is an activated amine-reactive carbonate.
  • R is preferably uncharged. Reaction of the masking agent carbonate with a polymer amine yields a carbamate linkage. The masking agent is stable until the dipeptide is cleaved in vivo by an endogenous protease, thus cleaving the steric stabilizer or targeting ligand from the polyamine. Following enzymatic cleavage after the dipeptide (between A 2 and the amidobenzyl), the amidobenzyl-carbamate undergoes a spontaneous rearrangement which results in regeneration of the polymer amine.
  • a preferred steric stabilizer is a polyethylene glycol (PEG).
  • a preferred targeting ligand for liver delivery is an ASGPr ligand.
  • a preferred ASGPr ligand is an N-Acetylgalactosamine (NAG).
  • a preferred amidobenzyl group is a p-amidobenzyl group.
  • Dipeptides of the dipeptide masking agents are dimers of amino acids connected via amide bonds.
  • Amino acids, including a and ⁇ amino acids are well known in biology and chemistry and are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids.
  • a preferred amino acid is an a-amino acid having the generic formula H2NCHRCOOH, where R is an organic substituent.
  • a preferred a amino acid is an uncharged naturally occurring amino acid.
  • a l is a hydrophobic amino acid and A2 is an uncharged hydrophilic amino acid.
  • a preferred hydrophobic amino acid is phenylalanine, valine, isoleucine, leucine, alanine, or tryptophan.
  • a preferred uncharged hydrophilic amino acid is asparagine, glutamine, or citruiline.
  • a more preferred hydrophobic amino acid is phenylalanine or valine.
  • a more preferred uncharged hydrophilic amino acid is citruiline.
  • dipeptides are preferred, it is possible to insert additional amino acids between A 1 and R. It is also possible to use a single amino acid instead of a dipeptide by eliminating amino acid A . Any natural amino acids used in the present invention are referred to herein by their common abbreviations. While charged amino acids can be used, it is preferred that the masking agent be uncharged.
  • an amphipathic membrane active polyamine is reversibly modified by reaction with a dipeptide-amidobenzyl-carbonate masking agent of the invention to yield a membrane inactive delivery polymer.
  • the dipeptide masking agents can shield the polymer from non-specific interactions, increase circulation time, enhance specific interactions, inhibit toxicity, or alter the charge of the polymer.
  • Reversibly masked polymers of the invention comprise the structure:
  • X is -NH-, -0-, or -CH 2 -
  • Y is -NH- or -O- Rl is preferably
  • R2 is preferably hydrogen (glycine)
  • R 1 and R 2 are alkyl groups
  • R4 comprises a polyethylene glycol or targeting ligand
  • the polyamine is an amphipathic membrane active polyamine. While the structure above indicates a single dipeptide masking agent linked to the polymer, in practice of the invention, 50% to 90% or more of polymer amines are modified by dipeptide masking agents.
  • reversibly masked polymer of the invention comprise structure:
  • Reversibly masked polymers of the invention are formed by reaction of dipeptide masking agents of the invention with amines on the polymer.
  • Dipeptide masking agents of the invention have the structure: wherein:
  • R5 is at position 2, 4, or 6 and is -CH 2 -0-C(0)-0-Z wherein Z is
  • X is -NH-
  • Y is -NH-
  • R4 is uncharged
  • R5 is at position 4
  • R6 is hydrogen as shown by:
  • R4 is:
  • R-(0-CH 2 -CH 2 ) s -0-Y l -, wherein R is hydrogen, methyl, or ethyl; and s is an integer from 1 to 150, and Yl is a linker selected from the list comprising:
  • a targeting ligand may be selected from the list comprising hapten, vitamin, antibody, monoclonal antibody, and cell surface receptor ligand.
  • a targeting ligand may be linked to the dipeptide via a linker such as a PEG linker.
  • Non-limiting examples of membrane active polymers suitable for use with the invention have been previously described in US Patent Publications 20080152661 , 20090023890, 20080287630, and 201 10207799.
  • Suitable amphipathic membrane active polyamine can also be small peptides such as a melittin peptide.
  • Polymer amines were reversibly modified using the enzyme cleavable linkers described herein.
  • An amine is reversibly modified if cleavage of the modifying group results in regeneration of the amine.
  • Reaction of the activated carbonate of the masking agent with a polymer amine connects a targeting ligand or steric stabilizer to the polymer via a peptidase cleavable dipeptide-amidobenzyl carbamate linkage as shown:
  • R 1 comprises an targeting ligand (either with or without protecting groups) or a PEG
  • R 2 is an amphipathic membrane active polyamine
  • AA is a dipeptide (either with or without protecting groups)
  • Z is an amine-reactive carbonate.
  • Protecting groups may be used during synthesis of the dipeptide masking agents. If present, protecting groups may be removed prior to or after modification of the amphipathic membrane active polyamine. Reversible modification of a sufficient percentage of the polymer amines with the dipeptide masking agents inhibits membrane activity of the membrane active po!yamine. Modification of polymer amines with the dipeptide masking agents also preferably neutralizes charge of the amine.
  • the dipeptide-amidobenzyl-carbamate linkage is susceptible to protease (or peptidase) cleavage. In presence of protease, the anilide bond is cleaved, resulting in an intermediate which immediately undergoes a 1 ,6 elimination reaction to release free polymer:
  • AA is a dipeptide
  • R comprises a targeting ligand or a steric stabilizer
  • R 2 is an amphipathic membrane active polyamine.
  • the free polymer is unmodified and so membrane activity it restored.
  • the reversibly masked membrane active polyamine does not exhibit membrane disruptive activity.
  • Reversible modification of more than 50%, more than 55%, more than 60%, more than 65%, more than 70%, more than 75%, more than 80%, or more than 90% of the amines on the polyamine with dipeptide masking agents may be required to inhibit membrane activity and provide cell targeting function, i.e. form a reversibly masked membrane active polymer (delivery polymer).
  • the present invention also provides a method for delivery of a biologically active substance, into cells. More specifically, the present invention is directed to compounds, compositions, and methods useful for delivering RNAi polynucleotides mammalian cells in vivo.
  • the RNAi polynucleotide is linked to the delivery polymer of the invention via a physiologically labile covalent linkage.
  • a physiologically labile linkage the polynucleotide can be cleaved from the polymer, releasing the polynucleotide to engage in functional interactions with cell components.
  • the invention includes conjugate delivery systems of the general structure: wherein N is a RNAi polynucleotide, L 1 is a physiologically labile linkage, P is an amphipathic membrane active polyamine, M 1 is an targeting ligand linked to P via a dipeptide-amidobenzyl-carbamate linkage, and M 2 is a steric stabilizer linked to P via a dipeptide-amidobenzyl-carbamate linkage, y and z are each integers greater than or equal to zero provided y + z has a value greater than 50%, greater than 60%, greater than 70%, greater than 80% or greater than 90% of the primary amines on polyamine P, as determined by the quantity of amines on P in the absence of any masking agents.
  • P is a membrane active polyamine.
  • Delivery polymer M' Y -P-M 2 2 is not membrane active. Reversible modification of P primary amines, by attachment of M 1 and/or M 2 , reversibly inhibits or inactivates membrane activity of P. It is noted that some small amphipathic membrane active polyamine, such as melittin peptide, contain as few as 3-5 primary amines. Modification of a percentage of amines is meant to reflect the modification of a percentage of amines in a population of polymers. Upon cleavage of M 1 and M 2 , amines of the polyamine are regenerated thereby reverting P to its unmodified, membrane active state.
  • the RNAi polynucleotide is co-administered in vivo with a delivery polymer of the invention.
  • the invention includes compositions of the general structure:
  • N is a RNAi polynucleotide
  • T is a targeting group
  • P is an amphipathic membrane active polyamine
  • M' is a targeting ligand linked to P via a dipeptide-amidobenzyl-carbamate linkage
  • M 2 is a steric stabilizer linked to P via a dipeptide-amidobenzyl-carbamate linkage
  • y and z are each integers greater than or equal to zero provided y + z has a value greater than 50%, greater than 60%, greater than 70%, greater than 80% or greater than 90% of the primary amines on polyamine P, as determined by the quantity of amines on P in the absence of any masking agents.
  • P is a membrane active polyamine.
  • Delivery polymer M'y-P-M 2 -. is not membrane active.
  • Reversible modification of P primary amines, by attachment of M 1 and/or M 2 reversibly inhibits or inactivates membrane activity of P.
  • some small amphipathic membrane active polyamine, such as melittin peptide contain as few as 3-5 primary amines. Therefore, modification of a percentage of amines is meant to reflect the modification of a percentage of amines in a population of polymers.
  • N is linked to T via a covalent bond to form a RNAi po!ynuc!eotide-targeting group conjugate using methods standard in the art.
  • a preferred covalent bond is a physiologically labile bond.
  • N ⁇ T The delivery polymer and N-T are synthesized or manufactured separately. Neither T nor N are covalently linked directly or indirectly to P, M 1 or M 2 . Electrostatic or hydrophobic association of the polynucleotide or the polynucleotide-conjugate with the masked or unmasked polymer is not required for in vivo liver delivery of the polynucleotide.
  • the masked polymer and the polynucleotide conjugate can be supplied in the same container or in separate containers. They may be combined prior to administration, co-administered, or administered sequentially.
  • RNAi polynucleotide is linked to the delivery polymer via a covalent bond or co-administered with the delivery polymer
  • y has a value greater than 50% and up to 100% of the primary amines on polymer P.
  • z therefore has a value greater or equal to zero percent (0%) but less than 50% of the primary amines on polymer P.
  • z may have a value greater up to 100% of the primary amines on polymer P. In a preferred embodiment, for delivery to tumor cells, z has a value greater than 50%, greater than 60%, greater than 70%, greater than 80% or greater than 90% of the primary amines on polyamine P and y is zero.
  • Membrane active polyamines are capable of disrupting plasma membranes or lysosomal/endocytic membranes. This membrane activity is an essential feature for cellular delivery of the polynucleotide. Membrane activity, however, leads to toxicity when the polymer is administered in vivo. Polyamines also interact readily with many anionic components in vivo, leading to undesired bio-distribution. Therefore, reversible masking of membrane activity of the polyamine is necessary for in vivo use. Masking is accomplished through reversible attachment of the described dipeptide masking agents to the membrane active polyamine to form a reversibly masked membrane active polymer, i.e. a delivery polymer.
  • the masking agents shield the polymer from non-specific interactions, reduce serum interactions, neutralize the polyamine to reduce positive charge and form a near neutral charge polymer, increase circulation time, and/or provide cell-specific interactions, i.e. targeting.
  • masking agents may shield the polymer from non-specific interactions (reduce serum interactions, increase circulation time).
  • the membrane active polyamine is membrane active in the unmodified (unmasked) state and not membrane active (inactivated) in the modified (masked) state.
  • a sufficient number of masking agents are linked to the polymer to achieve the desired level of inactivation.
  • the desired level of modification of a polymer by attachment of masking agent(s) is readily determined using appropriate polymer activity assays. For example, if the polymer possesses membrane activity in a given assay, a sufficient level of masking agent is linked to the polymer to achieve the desired level of inhibition of membrane activity in that assay.
  • Masking requires modification of >50%, >60%, >70%, >80% or >90% of the primary amine groups on a population of polymer, as determined by the quantity of primary amines on the polymer in the absence of any masking agents. It is also a preferred characteristic of masking agents that their attachment to the polymer reduces positive charge of the polymer, thus forming a more neutral delivery polymer. It is desirable that the masked polymer retain aqueous solubility.
  • the membrane active polyamine can be conjugated to masking agents in the presence of an excess of masking agents. The excess masking agent may be removed from the conjugated delivery polymer prior to administration of the delivery polymer.
  • a "steric stabilizer” is a non-ionic hydrophilic polymer (either natural, synthetic, or non-natural) that prevents or inhibits intramolecular or intermolecular interactions of a polymer to which it is attached relative to the polymer containing no steric stabilizer.
  • a steric stabilizer hinders a polymer to which it is attached from engaging in electrostatic interactions. Electrostatic interaction is the non-covalent association of two or more substances due to attractive forces between positive and negative charges.
  • Steric stabilizers can inhibit interaction with blood components and therefore opsonization, phagocytosis, and uptake by the reticuloendothelial system. Steric stabilizers can thus increase circulation time of molecules to which they are attached.
  • Steric stabi lizers can also inhibit aggregation of a polymer.
  • a preferred steric stabilizer is a polyethylene glycol (PEG) or PEG derivative.
  • PEG polyethylene glycol
  • a preferred PEG can have about 1 -500 ethylene glycol monomers, or 2-25.
  • a preferred PEG can also have a molecular weight average of about 85-20,000 Daltons (Da), about 85-1000 Da.
  • steric stabilizers prevent or inhibit intramolecular or intermolecular interactions of a polymer to which it is attached relative to the polymer containing no steric stabilizer in aqueous solution.
  • Targeting ligands enhance the pharmacokinetic or biodistribution properties of a conjugate to which they are attached to improve cell- or tissue-specific distribution and cell-specific uptake of the conjugate.
  • 'targeting ligand' is used to denote a targeting ligand that is attached to a dipeptide masking agent
  • 'targeting group' is a targeting ligand that is linked to an RNAi polynucleotide in an RNAi polynucleotide- targeting group conjugate.
  • Targeting ligands enhance the association of molecules with a target cell.
  • targeting ligands can enhance the pharmacokinetic or biodistribution properties of a conjugate to which they are attached to improve cellular distribution and cellular uptake of the conjugate. Binding of a targeting ligand to a cell or cell receptor may initiate endocytosis.
  • Targeting ligands may be monovalent, divalent, trivalent, tetravalent, or have higher valency.
  • Targeting ligands may be selected from the group comprising: compounds with affinity to cell surface molecule, cell receptor ligands, antibodies, monoclonal antibodies, antibody fragments, and antibody mimics with affinity to cell surface molecules.
  • a preferred targeting ligand comprises a cell receptor ligand.
  • Cell receptor ligands may be selected from the group comprising: carbohydrates, glycans, saccharides (including, but not limited to: galactose, galactose derivatives, mannose, and mannose derivatives), vitamins, folate, biotin, aptamers, and peptides (including, but not limited to: RGD-containing peptides, insulin, EGF, and transferrin).
  • a preferred targeting ligand is a saccharide having affinity for the asialoglycoprotein receptor (ASGPr).
  • ASGPr asialoglycoprotein receptor
  • Galactose and galactose derivates have been used to target molecules to hepatocytes in vivo through their binding to the ASGPr expressed on the surface of hepatocytes.
  • a "ASGPr targeting ligand” comprises a galactose and galactose derivative having affinity for the ASGPr equal to or greater than that of galactose.
  • ASGPr targeting ligands may be selected from the group comprising: lactose, galactose, N- acetylgalactosamine (NAG), galactosamine, N-formylgalactosamine, N-acetyl- galactosamine, N-propionylgalactosamine, N-n-butanoylgalactosamine, and N-iso-butanoyl- galactosamine (lobst, S.T. and Drickamer, . J.B.C. 1996, 271, 6686).
  • ASGPr targeting moieties can be monomeric (e.g., having a single galactosamine) or multimeric (e.g., having multiple galactosamines).
  • the membrane active polyamine is reversibly masked by attachment of ASGPr targeting ligand masking agents to >50%, >60%, >70%, >80%, or >90% of primary amines on the polyamine.
  • the membrane active polyamine is reversibly masked by attachment of ASGPr targeting ligand masking agents and PEG masking agents to>50%, >60%, >70%, >80%, or >90% of primary amines on the polymer.
  • a ratio of PEG to ASGPr targeting ligand is about 0-4: 1 , more preferably about 0.5-2: 1.
  • amphipathic or amphiphilic, polymers are well known and recognized in the art and have both hydrophilic (polar, water-soluble) and hydrophobic (non-polar, lipophilic, water- insoluble) groups or parts.
  • Hydrophilic groups indicate in qualitative terms that the chemical moiety is water- preferring. Typically, such chemical groups are water soluble, and are hydrogen bond donors or acceptors with water.
  • a hydrophilic group can be charged or uncharged. Charged groups can be positively charged (anionic) or negatively charged (cationic) or both (zwitterionic).
  • hydrophilic groups include the following chemical moieties: carbohydrates, polyoxyethylene, certain peptides, oligonucleotides, amines, amides, alkoxy amides, carboxylic acids, sulfurs, and hydroxyls.
  • Hydrophobic groups indicate in qualitative terms that the chemical moiety is water- avoiding. Typically, such chemical groups are not water soluble, and tend not to form hydrogen bonds. Lipophilic groups dissolve in fats, oils, lipids, and non-polar solvents and have little to no capacity to form hydrogen bonds. Hydrocarbons containing two (2) or more carbon atoms, certain substituted hydrocarbons, cholesterol, and cholesterol derivatives are examples of hydrophobic groups and compounds. Hydrophobic groups are preferably hydrocarbons, containing only carbon and hydrogen atoms. However, non-polar substitutions or non-polar heteroatoms which maintain hydrophobicity, and include, for example fluorine, may be permitted.
  • hydrophobic group also includes: sterols, steroids, cholesterol, and steroid and cholesterol derivatives.
  • amphipathic polymers a part is defined as a molecule derived when one covalent bond is broken and replaced by hydrogen. For example, in butyl amine, a breakage between the carbon and nitrogen bonds, and replacement with hydrogens, results in ammonia (hydrophilic) and butane (hydrophobic). If 1 ,4-diaminobutane is cleaved at nitrogen-carbon bonds, and replaced with hydrogens, the resulting molecules are again ammonia (2*) and butane. However, 1 ,4,-diaminobutane is not considered amphipathic because formation of the hydrophobic part requires breakage of two bonds.
  • a surface active polymer lowers the surface tension of water and/or the interfacial tension with other phases, and, accordingly, is positively adsorbed at the liquid/vapor interface.
  • the property of surface activity is usually due to the fact that the molecules of the substance are amphipathic or amphiphilic.
  • membrane active polymers are surface active, amphipathic polymers that are able to induce one or more of the following effects upon a biological membrane: an alteration or disruption of the membrane that allows non-membrane permeable molecules to enter a cell or cross the membrane, pore formation in the membrane, fission of membranes, or disruption or dissolving of the membrane.
  • a membrane, or cell membrane comprises a lipid bilayer.
  • the alteration or disruption of the membrane can be functionally defined by the polymer's activity in at least one the following assays: red blood cell lysis (hemolysis), liposome leakage, liposome fusion, cell fusion, cell lysis, and endosomal release.
  • Membrane active polymers that can cause lysis of cell membranes are also termed membrane lytic polymers. Polymers that preferentially cause disruption of endosomes or lysosomes over plasma membrane are considered endosomolytic. The effect of membrane active polymers on a cell membrane may be transient. Membrane active possess affinity for the membrane and cause a denaturation or deformation of bilayer structures. Membrane active polymers may be synthetic or non-natural amphipathic polymers.
  • membrane active polymers are distinct from a class of polymers termed cell penetrating peptides or polymers represented by compounds such as the arginine-rich peptide derived from the HIV TAT protein, the antennapedia peptide, VP22 peptide, transportan, arginine-rich artificial peptides, small guanidintum-rich artificial polymers and the like. While cell penetrating compounds appear to transport some molecules across a membrane, from one side of a lipid bilayer to other side of the lipid bilayer, apparently without requiring endocytosis and without disturbing the integrity of the membrane, their mechanism is not understood.
  • a polynucleotide to a cell is mediated by the membrane active polymer disrupting or destabilizing the plasma membrane or an internal vesicle membrane (such as an endosome or lysosome), including forming a pore in the membrane, or disrupting endosomal or lysosomal vesicles thereby permitting release of the contents of the vesicle into the cell cytoplasm.
  • an internal vesicle membrane such as an endosome or lysosome
  • Amphipathic membrane active polyamine copolymers of the invention are the product of copolymerization of two or more monomer species.
  • amphipathic membrane active heteropolymers of the invention have the general structure:
  • A contains a pendent primary or secondary amine functional group and B contains a pendant hydrophobic group, a and b are integers >0.
  • the polymers may be random, block, or alternating. The incorporation of additional monomers is permissible.
  • Endosomolytic polymers are polymers that, in response to an endosomal-specific environmental factors, such as the presence of lytic enzymes, are able to cause disruption or lysis of an endosome or provide for release of a normally cell membrane impermeable compound, such as a polynucleotide, from a cellular internal membrane-enclosed vesicle, such as an endosome or lysosome.
  • Endosomolytic polymers undergo a shift in their physico- chemical properties in the endosome. This shift can be a change in the polymer's solubility or ability to interact with other compounds or membranes as a result in a shift in charge, hydrophobicity, or hydrophilicity.
  • a reversibly masked membrane active polymamine of the invention are considered to be endosomolytic polymers.
  • Melittin is a small amphipathic membrane active peptide which naturally occurs in bee venom. Melittin can be isolated from a biological source or it can be synthetic. A synthetic polymer is formulated or manufactured by a chemical process "by man” and is not created by a naturally occurring biological process. As used herein, melittin encompasses the naturally occurring bee venom peptides of the melittin family that can be found in, for example, venom of the species: Apis mellifera, Apis cerana, Vespula maculifrons, Vespa magnifica, Vespa velutina nigrithorax, Polistes sp.
  • melittin also encompasses synthetic peptides having amino acid sequence identical to or similar to naturally occurring melittin peptides. Specifically, melittin amino acid sequence encompass those shown in Table 1. Synthetic melittin peptides can contain naturally occurring L form amino acids or the enantiomeric D form amino acids (inverso). However, a melittin peptide should either contain essentially all L form or all D form amino acids but may have amino acids of the opposite stereocenter appended at either the amino or carboxy termini.
  • the melittin amino acid sequence can also be reversed (reverso).
  • Reverso melittin can have L form amino acids or D form amino acids (retroin verso).
  • Two melittin peptides can also be covalently linked to form a melittin dimer.
  • Melittin can have modifying groups, other than masking agents, that enhance tissue targeting or facilitate in vivo circulation attached to either the amino terminal or carboxy terminal ends.
  • a linkage or "linker” is a connection between two atoms that links one chemical group or segment of interest to another chemical group or segment of interest via one or more covalent bonds.
  • a linkage can connect a masking agent or polynucleotide to a polymer.
  • a labile linkage contains a labile bond.
  • a linkage may optionally include a spacer that increases the distance between the two joined atoms. A spacer may further add flexibility and/or length to the linkage.
  • Spacers may include, but are not be limited to, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, aralkyl groups, aralkenyl groups, aralkynyl groups; each of which can contain one or more heteroatoms, heterocycies, amino acids, nucleotides, and saccharides. Spacer groups are well known in the art and the preceding list is not meant to limit the scope of the invention.
  • a "labile bond” is a covalent bond other than a covalent bond to a hydrogen atom that is capable of being selectively broken or cleaved under conditions that will not break or cleave other covalent bonds in the same molecule.
  • a labile bond is a covalent bond that is less stable (thermodynamically) or more rapidly broken (kinetically) under appropriate conditions than other non-labile covalent bonds in the same molecule. Cleavage of a labile bond within a molecule may result in the formation of two molecules. For those skilled in the art, cleavage or lability of a bond is generally discussed in terms of half-life (t1 ⁇ 2) of bond cleavage (the time required for half of the bonds to cleave). Thus, labile bonds encompass bonds that can be selectively cleaved more rapidly than other bonds a molecule.
  • a "physiologically labile bond” is a labile bond that is cleavable under conditions normally encountered or analogous to those encountered within a mammalian body. Physiologically labile linkage groups are selected such that they undergo a chemical transformation (e.g., cleavage) when present in certain physiological conditions.
  • a cellular physiologically labile bond is a labile bond that is cleavable under mammalian intracellular conditions.
  • Mammalian intracellular conditions include chemical conditions such as pH, temperature, oxidative or reductive conditions or agents, and salt concentration found in or analogous to those encountered in mammalian cells. Mammalian intracellular conditions also include the presence of enzymatic activity normally present in a mammalian cell such as from proteolytic or hydrolytic enzymes.
  • a cellular physiologically labile bond may also be cleaved in response to administration of a pharmaceutically acceptable exogenous agent.
  • RNAi interference-targeting group conjugate A targeting group may be linked to the 3 ' or the 5' end of the RNAi polynucleotide.
  • the targeting moiety may be linked to either the sense strand or the antisense strand, though the sense strand is preferred.
  • the targeting group consists of a hydrophobic group More specifically, the targeting group consists of a hydrophobic group having at least 20 carbon atoms.
  • Hydrophobic groups used as polynucleotide targeting moieties are herein referred to as hydrophobic targeting moieties.
  • Exemplary suitable hydrophobic groups may be selected from the group comprising: cholesterol, dicholesterol, tocopherol, ditocopherol, didecyl, didodecyl, dioctadecyl, didodecyl, dioctadecyl, isoprenoid, and choleamide.
  • Hydrophobic groups having 6 or fewer carbon atoms are not effective as polynucleotide targeting moieties, while hydrophobic groups having 8 to 18 carbon atoms provide increasing polynucleotide delivery with increasing size of the hydrophobic group (i.e. increasing number of carbon atoms).
  • Attachment of a hydrophobic targeting group to an NAi polynucleotide does not provide efficient functional in vivo delivery of the RNAi polynucleotide in the absence of coadministration of the delivery polymer.
  • siRNA-cholesteroI conjugates have been reported by others to deliver siRNA (si NA-cholesterol) to liver cells in vivo, in the absence of any additional delivery vehicle, high concentrations of siRNA are required and delivery efficacy is poor.
  • delivery of the polynucleotide is greatly improved.
  • Hydrophobic groups useful as polynucleotide targeting moieties may be selected from the group consisting of: alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group, aralkenyl group, and aralkynyl group, each of which may be linear, branched, or cyclic, cholesterol, cholesterol derivative, sterol, steroid, and steroid derivative.
  • Hydrophobic targeting groups are preferably hydrocarbons, containing only carbon and hydrogen atoms. However, substitutions or heteroatoms which maintain hydrophobicity, for example fluorine, may be permitted.
  • the hydrophobic targeting group may be attached to the 3' or 5' end of the RNAi polynucleotide using methods known in the art.
  • the hydrophobic group may be attached to either strand.
  • the targeting group comprises a galactose cluster (galactose cluster targeting moiety).
  • a galactose cluster comprises a molecule having two to four terminal galactose derivatives.
  • galactose derivative includes both galactose and derivatives of galactose having affinity for the ASGPr equal to or greater than that of galactose.
  • a terminal galactose derivative is attached to a molecule through its C- 1 carbon.
  • a preferred galactose cluster has three terminal galactosamines or galactosamine derivatives each having affinity for the asialoglycoprotein receptor.
  • a more preferred galactose cluster has three terminal N-acetylgalactosamines.
  • Other terms common in the art include tri-antennary galactose, tri-valent galactose and galactose trimer. It is known that tri- antennary galactose derivative clusters bind to the ASGPr with greater affinity than bi- antennary or mono-antennary galactose derivative structures (Baenziger and Fiete, 1980, Cell, 22, 61 1 -620; Connolly et al., 1982, J. Biol. Chem., 257, 939-945). ultivalency is required to achieve n affinity.
  • a galactose cluster contains two-four, preferably three, galactose derivatives each linked to a central branch point.
  • the galactose derivatives are attached to the central branch point through the C-l carbons of the saccharides.
  • the galactose derivative is preferably linked to the branch point via linkers or spacers.
  • a preferred spacer is a flexible hydrophilic spacer (U.S. Patent 5885968; Biessen et al. J. Med. Chem. 1995 Vol. 39 p.
  • a preferred flexible hydrophilic spacer is a PEG spacer.
  • a preferred PEG spacer is a PEG3 spacer.
  • the branch point can be any smal l molecule which permits attachment of the three galactose derivatives and further permits attachment of the branch point to the RNAi polynucleotide.
  • An exemplary branch point group is a di-lysine.
  • a di-lysine molecule contains three amine groups through which three galactose derivatives may be attached and a carboxyl reactive group through which the di-lysine may be attached to the RNAi polynucleotide. Attachment of the branch point to the RNAi polynucleotide may occur through a linker or spacer.
  • a preferred spacer is a flexible hydrophilic spacer.
  • a preferred flexible hydrophilic spacer is a PEG spacer.
  • a preferred PEG spacer is a PEG3 spacer (three ethylene units).
  • the galactose cluster may be attached to the 3' or 5' end of the RNAi polynucleotide using methods known in the art. For RNAi polynucleotides having 2 strands, such as siRNA, the galactose cluster may be attached to either strand. Suitable galactose clusters are described in US Patent Publication 201 10207799.
  • polynucleotide or nucleic acid or polynucleic acid, is a term of art that refers to a polymer containing at least two nucleotides. Nucleotides are the monomeric units of polynucleotide polymers. Polynucleotides with less than 120 monomeric units are often called oligonucleotides. Natural nucleic acids have a deoxyribose- or ribose-phosphate backbone.
  • a non-natural or synthetic polynucleotide is a polynucleotide that is polymerized in vitro or in a cell free system and contains the same or similar bases but may contain a backbone of a type other than the natural ribose or deoxyribose-phosphate backbone.
  • Polynucleotides can be synthesized using any known technique in the art.
  • Polynucleotide backbones known in the art include: PNAs (peptide nucleic acids), phosphorothioates, phosphorodiamidates, morpholinos, and other variants of the phosphate backbone of native nucleic acids.
  • Bases include purines and pyrim idines, which further include the natural compounds adenine, thymine, guanine, cytosine, uracil, inosine, and natural analogs. Synthetic derivatives of purines and pyrimidines include, but are not limited to, modifications which place new reactive groups on the nucleotide such as, but not limited to, amines, alcohols, thiols, carboxylates, and alkylhalides.
  • the term base encompasses any of the known base analogs of DNA and RNA.
  • a polynucleotide may contain ribonucleotides, deoxyribonucleotides, synthetic nucleotides, or any suitable combination.
  • Polynucleotides may be polymerized in vitro, they may be recombinant, contain chimeric sequences, or derivatives of these groups.
  • a polynucleotide may include a terminal cap moiety at the 5' - end, the 3' -end, or both the 5' and 3' ends.
  • the cap moiety can be, but is not limited to, an inverted deoxy abasic moiety, an inverted deoxy thymidine moiety, a thymidine moiety, or 3' glyceryl modification.
  • RNA interference (RNAi) polynucleotide is a molecule capable of inducing RNA interference through interaction with the RNA interference pathway machinery of mammalian cells to degrade or inhibit translation of messenger RNA (mRNA) transcripts of a transgene in a sequence specific manner.
  • Two primary RNAi polynucleotides are small (or short) interfering RNAs (siRNAs) and micro RNAs (miRNAs).
  • siRNA small (or short) interfering RNAs
  • miRNAs micro RNAs
  • miRNAs micro RNAs
  • RNAi polynucleotides may be selected from the group comprising: siRNA, microRNA, double-strand RNA (dsRNA), short hairpin RNA (shRNA), and expression cassettes encoding RNA capable of inducing RNA interference.
  • siRNA comprises a double stranded structure typically containing 15-50 base pairs and preferably 21 -25 base pairs and having a nucleotide sequence identical (perfectly complementary) or nearly identical (partially complementary) to a coding sequence in an expressed target gene or RNA within the cell.
  • An siRNA may have dinucleotide 3' overhangs.
  • An siRNA may be composed of two annealed polynucleotides or a single polynucleotide that forms a hairpin structure.
  • An siRNA molecule of the invention comprises a sense region and an antisense region.
  • the siRNA of the conjugate is assembled from two oligonucleotide fragments wherein one fragment comprises the nucleotide sequence of the antisense strand of the siRNA molecule and a second fragment comprises nucleotide sequence of the sense region of the siRNA molecule.
  • the sense strand is connected to the antisense strand via a linker molecule, such as a polynucleotide linker or a non-nucleotide linker.
  • miRNAs are small noncoding RNA gene products about 22 nucleotides long that direct destruction or translational repression of their mRNA targets.
  • the complementarity between the miRNA and the target mRNA is partial, translation of the target mRNA is repressed. If complementarity is extensive, the target mRNA is cleaved.
  • the complex binds to target sites usually located in the 3' UTR of mRNAs that typically share only partial homology with the miRNA.
  • a "seed region" a stretch of about seven (7) consecutive nucleotides on the 5' end of the miRNA that forms perfect base pairing with its target— plays a key role in miRNA specificity. Binding of the RISC/miRNA complex to the mRNA can lead to either the repression of protein translation or cleavage and degradation of the mRNA. Recent data indicate that mRNA cleavage happens preferentially if there is perfect homology along the whole length of the miRNA and its target instead of showing perfect base-pairing only in the seed region (Pillai et al. 2007).
  • RNAi polynucleotide expression cassettes can be transcribed in the cell to produce small hairpin RNAs that can function as siRNA, separate sense and anti-sense strand linear siRNAs, or miRNA.
  • RNA polymerase III transcribed DNAs contain promoters selected from the list comprising: U6 promoters, HI promoters, and tRNA promoters.
  • RNA polymerase II promoters include Ul, U2, U4, and U5 promoters, snRNA promoters, microRNA promoters, and mRNA promoters.
  • RNAi molecules are readily designed and produced by technologies known in the art.
  • computational tools that increase the chance of finding effective and specific sequence motifs (Pei et al. 2006, Reynolds et al. 2004, Khvorova et al. 2003, Schwarz et al. 2003, Ui-Tei et al. 2004, Heale et al. 2005, Chalk et al. 2004, Amarzguioui et al. 2004).
  • the polynucleotides of the invention can be chemically modified.
  • chemical modifications include: phosphorothioate internucleotide linkages, 2'-0-methyI ribonucleotides, 2'-deoxy-2'-fluoro ribonucleotides, 2'-deoxy ribonucleotides, "universal base” nucleotides, 5-C -methyl nucleotides, and inverted deoxyabasic residue incorporation.
  • These chemical modifications when used in various polynucleotide constructs, are shown to preserve polynucleotide activity in cells while at the same time increasing the serum stability of these compounds. Chemically modified siRNA can also minimize the possibility of activating interferon activity in humans.
  • a chemically-modified RNAi polynucleotide of the invention comprises a duplex having two strands, one or both of which can be chemically-modified, wherein each strand is about 19 to about 29 nucleotides.
  • an RNAi polynucleotide of the invention comprises one or more modified nucleotides while maintaining the ability 1 to mediate RNAi inside a cell or reconstituted in vitro system.
  • An RNAi polynucleotide can be modified wherein the chemical modification comprises one or more (e.g., about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more) of the nucleotides.
  • RNAi polynucleotide of the invention can comprise modified nucleotides as a percentage of the total number of nucleotides present in the RNAi polynucleotide.
  • an RNAi polynucleotide of the invention can generally comprise modified nucleotides from about 5 to about 100% of the nucleotide positions (e.g., 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 100% of the nucleotide positions).
  • the actual percentage of modified nucleotides present in a given RNAi polynucleotide depends on the total number of nucleotides present in the RNAi polynucleotide. If the RNAi polynucleotide is single stranded, the percent modification can be based upon the total number of nucleotides present in the single stranded RNAi polynucleotide.
  • the percent modification can be based upon the total number of nucleotides present in the sense strand, antisense strand, or both the sense and antisense strands, in addition, the actual percentage of modified nucleotides present in a given RNAi polynucleotide can also depend on the total number of purine and pyrimidine nucleotides present in the RNAi polynucleotide. For example, wherein all pyrimidine nucleotides and/or all purine nucleotides present in the RNAi polynucleotide are modified.
  • RNAi polynucleotide modulates expression of RNA encoded by a gene. Because multiple genes can share some degree of sequence homology with each other, an RNAi polynucleotide can be designed to target a class of genes with sufficient sequence homology. Thus, an RNAi polynucleotide can contain a sequence that has complementarity to sequences that are shared amongst different gene targets or are unique for a specific gene target. Therefore, the RNAi polynucleotide can be designed to target conserved regions of an RNA sequence having homology between several genes thereby targeting several genes in a gene family (e.g., different gene isoforms, splice variants, mutant genes, etc.). In another embodiment, the RNAi polynucleotide can be designed to target a sequence that is unique to a specific RNA sequence of a single gene.
  • complementarity refers to the ability of a polynucleotide to form hydrogen bond(s) with another polynucleotide sequence by either traditional Watson-Crick or other non-traditional types.
  • the binding free energy for a polynucleotide molecule with its target (effector binding site) or complementary sequence is sufficient to allow the relevant function of the polynucleotide to proceed, e.g., enzymatic mRNA cleavage or translation inhibition. Determination of binding free energies for nucleic acid molecules is well known in the art (Frier et al. 1986, Turner et al. 1987).
  • a percent complementarity indicates the percentage of bases, in a contiguous strand, in a first polynucleotide molecule which can form hydrogen bonds (e.g., Watson- Crick base pairing) with a second polynucleotide sequence (e.g., 5, 6, 7, 8, 9, 10 out of 10 being 50%, 60%, 70%, 80%, 90%, and 100% complementary).
  • Perfectly complementary means that all the bases in a contiguous strand of a polynucleotide sequence will hydrogen bond with the same number of contiguous bases in a second polynucleotide sequence.
  • inhibit, down-regulate, or knockdown gene expression it is meant that the expression of the gene, as measured by the level of RNA transcribed from the gene or the level of polypeptide, protein or protein subunit translated from the RNA, is reduced below that observed in the absence of the blocking polynucleotide-conjugates of the invention.
  • Inhibition, down-regulation, or knockdown of gene expression, with a polynucleotide delivered by the compositions of the invention is preferably below that level observed in the presence of a control inactive nucleic acid, a nucleic acid with scrambled sequence or with inactivating mismatches, or in absence of conjugation of the polynucleotide to the masked polymer.
  • siRNA stabilization against degradation by endosomal / lysosomal-localized nucleases such as DNAse II strongly improves target knock down. Such stabilization may directly affect the amount of siRNA released into the cytoplasm where the cellular RNAi machinery is located. Only the siRNA portion available in the cytoplasm will trigger the RNAi effect.
  • siRNAs are susceptible to nucleases in the biological environment when administered as such into the circulation without a protecting delivery vehicle. Accordingly, many siRNAs are rapidly degraded either extracellularly in the tissue and blood stream or after intracellular uptake (endosome).
  • Nuclease cleavage can be inhibited by nucleotides lacking a 2'-OH group such as 2'-deoxy, 2'-0-methyl (2'-OMe)or 2'-deoxy-2'-fluoro (2'-F) nucleotides and by polynucleotides 5'- terminal non-nucleotide moieties, like e.g. cholesterol, aminoalkyl-linker or a phosphothioate at the first internucleotide linkage.
  • nucleotides lacking a 2'-OH group such as 2'-deoxy, 2'-0-methyl (2'-OMe)or 2'-deoxy-2'-fluoro (2'-F) nucleotides and by polynucleotides 5'- terminal non-nucleotide moieties, like e.g. cholesterol, aminoalkyl-linker or a phosphothioate at the first internucleotide linkage.
  • the RNAi polynucleotide lack any 2'-OH nucleotide within the strand, starting with a 2'-OMe nucleotide at the 5'-end connected by a phosphorothioate (PTO) linkage to the second nucleotide.
  • siRNAs can be significantly stabilized when using the following design, wherein an oligonucleotide is provided with an antisense strand with the modification pattern: 5'-(w)- (Z1 )-(Z2)-(Z3)n a -3' and a sense strand with the modification pattern 5'-(Z3)n s -3' , wherein w is independently a 5'-phosphate or 5 '-phosphothioate or H,
  • Zl is independently a 2'-modified nuleoside.
  • Z2 is independently a 2'-deoxy nucleoside or 2'-Fluoro-modified nucleoside
  • Z3 is independently a 2'-modified nucleoside
  • n a is 8-23 and n s is 8-25.
  • an oligonucleotide is provided with an antisense strand with the modification pattern: 5'-(w)-(Zl )-(Z2)-(Z3)n a -3' and a sense strand with the modification pattern 5'-(Z3)n s -3', wherein Zl is a a 2'-Fluoro-modified nucleoside or a 2-deoxy-nucleoside and all remaining substituents as well as the variables n a and n s have the meaning given above.
  • an oligonucleotide is provided with an antisense strand with the modification pattern: 5'-(w)-(Zl )-(Z2)-(Z3)n a -3' and a sense strand with the modification pattern 5'-(Z3)n s -3', wherein Z3 is a 2'-0-Methyl modified nucleoside, a 2'-Fluoro-modified nucleoside or a 2-deoxy-nucleoside and all remaining substituents as well as the variables n a and n s have the meaning given above.
  • an oligonucleotide is provided with an antisense strand with the modification pattern: 5'-(w)-(Zl)-(Z2)-(Z3)n a -3' and a sense strand with the modification pattern 5'-(Z3)n s -3' , wherein Zl is a a 2'-Fluoro-modified nucleoside or a 2-deoxy- nucleoside and Z3 is a 2'-C>-Methyl modified nucleoside, a 2'-Fluoro-modified nucleoside or a 2-deoxy-nucleoside and all remaining substituents as well as the variables n a and n s have the meaning given above.
  • nucleosides in the nucleic acid sequence of the oligonucleotice with the novel modification pattern can either be linked by 5 -3' phosphodiesters or 5'-3' phosphorothioates.
  • the "anti-sense" strand is the siRNA strand that is complementary to the target mRNA and that will be binding to the mRNA once the siRNA is unwound.
  • the sense strand of said siRNA comprising the novel modification pattern is complimentary to the antisense strand.
  • a nuclease cleavage site between the RNAi polynucleotide and the targeting moiety or delivery polymer to which it is covalently attached can be introduced by 3'- or 5'- overhangs containing at least one 2'-OH nucleotide at either the sense or the antisense strand.
  • the final active siRNA species is generated by intracellular nuclease processing. Also, the use of defined cleavage sites implemented by 2'-OH nucleotides within the base paired region is possible.
  • the RNAi polynucleotide is linked to the deliver)' polymer via a physiologically labile bond or linker.
  • the physiologically labile linker is selected such that it undergoes a chemical transformation (e.g., cleavage) when present in certain physiological conditions, (e.g., disulfide bond cleaved in the reducing environment of the cell cytoplasm). Release of the polynucleotide from the polymer, by cleavage of the physiologically labile linkage, facilitates interaction of the polynucleotide with the appropriate cellular components for activity.
  • the polynucleotide-polymer conjugate is formed by covalently linking the polynucleotide to the polymer.
  • the polymer is polymerized or modified such that it contains a reactive group A.
  • the polynucleotide is also polymerized or modified such that it contains a reactive group B.
  • Reactive groups A and B are chosen such that they can be linked via a reversible covalent linkage using methods known in the art.
  • Conjugation of the polynucleotide to the polymer can be performed in the presence of an excess of polymer. Because the polynucleotide and the polymer may be of opposite charge during conjugation, the presence of excess polymer can reduce or eliminate aggregation of the conjugate. Alternatively, an excess of a carrier polymer, such as a polycation, can be used. The excess polymer can be removed from the conjugated polymer prior to administration of the conjugate to the animal or cell culture. Alternatively, the excess polymer can be co-administered with the conjugate to the animal or cell culture.
  • a route of administration is the path by which a drug, fluid, poison, or other substance is brought into contact with the body.
  • methods of administering drugs and nucleic acids for treatment of a mammal are well known in the art and can be applied to administration of the compositions of the invention.
  • the compounds of the present invention can be administered via any suitable route, most preferably parenteral!y, in a preparation appropriately tailored to that route.
  • the compounds of the present invention can be administered by injection, for example, intravenously, intramuscularly, intracutaneously, subcutaneously, or intraperitoneally.
  • the present invention also provides pharmaceutical compositions comprising a pharmaceutically acceptable carrier or excipient.
  • Parenteral routes of administration include intravascular (intravenous, intraarterial), intramuscular, intraparenchymal, intradermal, subdermal, subcutaneous, intratumor, intraperitoneal, intrathecal, subdural, epidural, and intralymphatic injections that use a syringe and a needle or catheter.
  • Intravascular herein means within a tubular structure called a vessel that is connected to a tissue or organ within the body.
  • a. bodily fluid flows to or from the body part. Examples of bodily fluid include blood, cerebrospinal fluid (CSF), lymphatic fluid, or bile.
  • CSF cerebrospinal fluid
  • lymphatic fluid or bile.
  • vessels examples include arteries, arterioles, capillaries, venules, sinusoids, veins, lymphatics, bile ducts, and ducts of the salivary or other exocrine glands.
  • the intravascular route includes delivery through the blood vessels such as an artery or a vein.
  • the blood circulatory system provides systemic spread of the pharmaceutical.
  • the described compositions are injected in pharmaceutically acceptable carrier solutions.
  • Pharmaceutically acceptable refers to those properties and/or substances which are acceptable to the mammal from a pharmacological/toxico logical point of view.
  • pharmaceutically acceptable refers to molecular entities, compositions, and properties that are physiologically tolerable and do not typically produce an allergic or other untoward or toxic reaction when administered to a mammal.
  • the term pharmaceutical ly acceptable means approved by a regulatory agency of the Federal or a state government or listed in the U.S. Pharmacopeia or other generally recognized pharmacopeia for use in animals and more particularly in humans.
  • carrier may also contain adjuvants such as preservatives, wetting agents, emulsifying agents and dispersing agents. Prevention of presence of microorganisms may be ensured both by sterilization procedures, supra, and by the inclusion of various antibacterial and antifungal agents, for example, paraben, chlorobutanol, phenol, sorbic acid, and the like. It may also be desirable to include isotonic agents, such as sugars, sodium chloride, and the like into the compositions. In addition, prolonged absorption of the injectable pharmaceutical form may be brought about by the inclusion of agents which delay absorption such as aluminum monostearate and gelatin.
  • adjuvants such as preservatives, wetting agents, emulsifying agents and dispersing agents. Prevention of presence of microorganisms may be ensured both by sterilization procedures, supra, and by the inclusion of various antibacterial and antifungal agents, for example, paraben, chlorobutanol, phenol, sorbic acid, and the like. It may also be desirable to
  • an RNAi polynucleotide-targeting group conjugate is co-administered with a delivery polymer of the invention.
  • co-administered it is meant that the RNAi polynucleotide conjugate and the delivery polymer are administered to the mammal such that both are present in the mammal at the same time.
  • the RNAi polynucleotide-targeting group conjugate and the delivery polymer may be administered simultaneously or they may be delivered sequentially. For simultaneous administration, they may be mixed prior to administration. For sequential administration, either the RNAi polynucleotide-targeting moiety conjugate or the delivery polymer may be administered first.
  • RNAi polynucleotides may be delivered for research purposes or to produce a change in a cell that is therapeutic. In vivo delivery of RNAi polynucleotides is useful for research reagents and for a variety of therapeutic, diagnostic, target validation, genomic discovery, genetic engineering, and pharmacogenomic applications.
  • RNAi polynucleotide delivery resulting in inhibition of endogenous gene expression in hepatocytes Levels of a reporter (marker) gene expression measured following delivery of a polynucleotide indicate a reasonable expectation of similar levels of gene expression following delivery of other polynucleotides. Levels of treatment considered beneficial by a person having ordinary skill in the art differ from disease to disease.
  • Hemophilia A and B are caused by deficiencies of the X-linked clotting factors VIII and IX, respectively. Their clinical course is greatly influenced by the percentage of normal serum levels of factor VIII or IX: ⁇ 2%, severe; 2-5%, moderate; and 5-30% mild. Thus, an increase from 1% to 2% of the normal level of circulating factor in severe patients can be considered beneficial. Levels greater than 6% prevent spontaneous bleeds but not those secondary to surgery or injury. Similarly, inhibition of a gene need not be 100% to provide a therapeutic benefit. A person having ordinary skill in the art of gene therapy would reasonably anticipate beneficial levels of expression of a gene specific for a disease based upon sufficient levels of marker gene results.
  • reporter or marker genes serve as useful paradigms for expression of intracellular proteins in general.
  • the liver is one of the most important target tissues for gene therapy given its central role in metabolism (e.g., lipoprotein metabolism in various hypercholesterolemias) and the secretion of circulating proteins (e.g., clotting factors in hemophilia).
  • acquired disorders such as chronic hepatitis and cirrhosis are common and are also potentially treated by polynucleotide-based liver therapies.
  • liver diseases and conditions which affect or are affected by the liver are potentially treated through knockdown (inhibition) of gene expression in the liver.
  • liver diseases and conditions may be selected from the list comprising: liver cancers (including hepatocellular carcinoma, HCC), viral infections (including hepatitis), metabolic disorders, (including hyperlipidemia and diabetes), fibrosis, and acute liver injury.
  • Actual dosage levels of the active ingredients in the pharmaceutical compositions of the present invention may be varied so as to obtain an amount of the active ingredient which is effective to achieve the desired therapeutic response for a particular patient, composition, and mode of administration, without being toxic to the patient.
  • the selected dosage level will depend upon a variety of pharmacokinetic factors including the activity of the particular compositions of the present invention employed, the route of administration, the time of administration, the rate of excretion of the particular compound being employed, the duration of the treatment, other drugs, compounds and/or materials used in combination with the ' particular compositions employed, the age, sex, weight, condition, general health and prior medical history of the patient being treated, and like factors well known in the medical arts.
  • the amount (dose) of delivery polymer, RNAi polynucleotide-targeting group conjugate or delivery polymer-RNAi polynucleotide conjugate that is to be administered can be determined empirically. We have shown effective knockdown of gene expression using 0. 1 - 1 0 mg/kg animal weight of siRNA and 1 .5-60 mg/kg animal weight delivery polymer. A preferred amount in mice is 0.25-2.5 mg/kg siRNA-conjugate and 1 0-40 mg/kg delivery polymer. More preferably, about 1 .5-20 mg/kg delivery polymer is administered. The amount of RNAi polynucleotide-conjugate is easily increased because it is typically not toxic in larger doses.
  • in vivo means that which takes place inside an organism and more specifically to a process performed in or on the living tissue of a whole, living multicellular organism (animal), such as a mammal, as opposed to a partial or dead one.
  • pharmaceutical composition includes the conjugates of the invention, a pharmaceutical carrier or diluent and any other media or agent necessary for formulation.
  • pharmaceutical carrier includes any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents, and the like that are physiologically compatible.
  • the carrier is suitable for intravenous, intramuscular, subcutaneous, parenteral, spinal or epidermal administration (e.g. by injection or infusion).
  • R comprises an ASGPr Iigand (protected or unprotected) or a PEG
  • a 1 and A 2 are amino acids (either protected or unprotected)
  • NHS esters of AA were prepared from respective amino acids with NHS and DCC and used without additional purification.
  • N-hydroxysuccinimide NHS
  • DCC N-N'-dicyclohexylcarbodiimide
  • Fmoc-Gly-NHS Fmoc-Gly-OH (891 mg, 3 mmol) and NHS (380 mg, 3.3 mmol) were stirred in THF (10 mL) at 0°C for 5 min and treated with a DCC solution (650 mg, 3.15 mmol) in THF (5 mL). The cooling bath was removed in 30 min and the reaction mixture was stirred at 20°C for 10 h. The solid DCU was filtered off, washed with THF and the solvent was removed on the rotovap. The product was weighed and dissolved in DME to make a 0.2 mM solution.
  • Fmoc-Glu(0-2PhiPr)-NHS DCC (217 mg, 1.05 mmol) was added to an ice cold solution of Fmoc-Glu(0-2PhiPr)-OH (487 mg, 1 mmol) and NHS (127 mg, 1 .1 mmol) in THF (5 mL), stirred for 15 min and then at 20°C for 10 h. The workup was done as described for Fmoc-Gly-NHS.
  • a 1 Ala
  • Phe A' Gly, Glu(2PhiPr), Asn(DMCP), Phe, Ala, Val.
  • a 2 Gly, Lys(MMT), Cit, Asn(DMCP), Lys(CH 3 ) 2 .
  • DME dimethoxyethane
  • THF tetrahydrofurane
  • H-A 2 -OH, NaHC0 3 , DME/THF/H2O H-Cit-OH, NaHC0 3 , THF in H 2 0.
  • Products la-h were coupled with p-aminobenzyl alcohol (PABA) in presence of 2-ethoxy-l - ethoxycarbonyl-l ,2-dihydroquinoline (EEDQ) to form 2a-h.
  • PABA p-aminobenzyl alcohol
  • EEDQ 2-ethoxy-l - ethoxycarbonyl-l ,2-dihydroquinoline
  • A' G!y, Glu(2PhiPr), Asn(D CP), Phe, Ala, Val.
  • a 2 Gly, Lys(MMT), Cit, Asn(D CP), Lys(CH 3 ) 2
  • a 1 Lys(CH 3 ) 2 , Leu, Asn(D CP), Cit
  • Fmoc-Glu(0-2PhiPr)Gly-PABA 2b a solution of lb (524 mg, 0.96 mmol) and PABA ( 142 mg, 1.55 mmol) in DCM (10 mL) was stirred with EEDQ (357 mg, 1.44 mmol) for 10 h. The workup was done as described above for 2a. Yield 462 mg (74%). Fmoc-Asn(DMCP)Gly-PABA 2c, was prepared as described above for 2a. Yield 64%. MS: 621.5 [M+22] + ; 599.3 [M+l ] + .
  • Fmoc-PheLys(MMT)-PABA 2d was prepared as described above for 2b. Yield 70 %.
  • Fmoc-AlaCit-PABA 2f a solution of If (2.89 g, 6.17 mmol) and PABA ( 1.52 g, 12.34 mmol) in DCM (45 mL) and MeOH ( 15 mL) was treated with EEDQ (3.05 g, 12.34 mmol) and stirred for 15 h. The workup was done as described above for 2a. Yield 4.56 g (74%). MS (ES, neg. mode): 307.4 [M-263.6-1 ] ' ; 349.9 [M-Fmoc- 1 ]-; 610, 608.4 [M+HCI- 1 ] " . Fmoc-Va!Cit-PABA 2g was prepared as described above for 2b. (98%).
  • Fmoc-AlaAsn(DMCP)-PABA 2h was prepared as described above for 2a. Yield 59%. MS: 613.2 [M+l] + ; 53 1.4 [M-DMCP+l f; 408.2 [M-205+l ] + .
  • Fmoc-Lys(CH 3 ) 2 -PABA 2i Fmoc-Lys(CH 3 ) 2 -OH HC1 salt (433 mg, l mmo! and PABA (246 mg, 2 mmol) were dissolved in DCM (10 mL) and MeOH (1.5 mL), cooled to 5°C and EEDQ (495 mg, 2 mmol) was added. The cooling bath was removed and the mixture was stirred for 10 h at room temperature. All volatiles were removed on a rotovap, the residue was triturated with Et 2 0, and the crude product was filtered off.
  • Fmoc-Asn(DMCP)-PABA 2k was prepared as described for 2j. In workup instead of column purification after removing of DCM the residue was triturated with Et 2 0, chilled to 0°C and the crude product was filtered off. This treatment was repeated one more time followed by drying in vacuo. Yield 77%. MS: 542.5 [M+l] + .
  • Fmoc-Cit-PABA 21 For Fmoc-Cit-PABA 21, a solution of Fmoc-Cit-OH (345.7 mg, 0.87 mmol) and PABA (214 mg, 1.74 mmol) in DCM ( 10 mL) and MeOH (4 mL) was treated with EEDQ (430 mg, 1.74 mmol) and stirred for 15 h. The solid product was triturated three times with ether, and the product was filtered and dried. Yield 288 mg (67%).
  • Product 2m was prepared using different scheme: coupling of H-Lys(CH 3 ) 2 -PABA derivative
  • Fmoc-PheLys(CH 3 )-PABA 2m Fmoc-Lys(CH 3 ) 2 -PABA (2i) (448 mg, 0.83 mmol) was Fmoc deprotected by stirring with Et 3 N (3.5 mL) in DMF ( 1 l mL) for lOh. All volatiles were removed on a rotovap at 40°C/oil pump vacuum to obtain the crude product 3i. This product was dissolved in DMF (7 mL), Fmoc-Phe-NHS (482 mg, 0.996 mmol) was added followed by DIEA (0.42 mL, 2.2 mmol) and the mixture was stirred for 10 h. The solvent with DIEA was removed on a rotovap at 40°C/oil pump vacuum to obtain crude 2m which was used without additional purification. MS: 549.4 [M+l] + .
  • NAG(R L ,R 2 ,R 3 )-L-AA-PABC-PNP where R 1 , R 2 and R 3 are protective groups and L is a linkage between galactosamine moiety (NAG) and dipeptide (AA) starts from preparation of NAG-L-CO2H acids 6, 10a, b, 13 and 17 which, fol lowing conversion into NHS ester, were used to acylate H-AA-PABA 2.
  • NAG-L-CO2H acids 6, 10a, b, 13 and 17 which, fol lowing conversion into NHS ester, were used to acylate H-AA-PABA 2.
  • carbonates 21 a-f designed for base sensitive polymers protective groups had to be removed before polymer modification.
  • NAG-amine 5 For preparation of 5 a solution of NAG 4 (6.74 g, 1 1.85 mmol) in MeOH (144 mL) and CHC1 3 (36 mL) was hydrogenated in the presence of 10% Pd/C (674 mg) at 1 atm. for 10 h. The catalyst was filtered off through celite, the product was concentrated and dried in vacuo. Yield 5.04 g (98%).
  • NAG-L' -OH 6 For preparation of 6 a solution of succinic anhydride (966 mg, 9.65 mmol) in DCM (30 mL) was added to NAG-amine 5 (4g, 9.15 mmol) in DCM (50 mL) followed by Et 3 N (1.964 mL, 14 mmol). After 1 h the reaction mixture was concentrated and dried in vacuo. The product was purified on a column, eluent gradient of MeOH (5-7%) in CHC1 3 . Yield 3.1 g (63%). MS: 535.3 [M+l ] + ; 330.3 [product of deg!ycosylation] + . b) NAG derivatives with easily removable sily!
  • ether protective groups were prepared by O-deacetylation of 4 in a mixture of triethylamine in aqueous methanol followed by treatment with trialkylsilyl chlorides.
  • NAG 4 (2g, 3.52 mmol) was O-deacetylated by stirring in a solution of MeOH ( 10 mL), H 2 0 (32 mL), and Et 3 N (25 mL) for 10 h. All volatiles were removed on a rotovap at 40°C and the residue was dried by two evaporations of toluene from the reaction mixture. The product 7 was directly used in the following step. MS: 544.3 [M+Et 3 N+l] + ; 443.7 [M+l f; 204 [product of deglycosylation] + .
  • Product 10a was prepared as a mixture of TBDMS and TES di Si-protected NAG derivatives following procedure described for 10b below.
  • the precursor 5 was first acetyl -deprotected to yield 11 (Et 3 N, MeOH, H 2 0 (5:7:6) l Oh). 11 was then acylated with bis-dPEGshalf benzyl half NHS ester (Quanta product cat. # 10237) to yield the benzyl ester 12 (NHS-PEG 5 -C0 2 Bn, Et 3 N, DCM). 12 was subsequently bis-silylated with TBDMSCI (TBDMSCI (3 eq.), imidazole, l Oh in DMF) and debenzylated by hydrogenation (H2, Pd/C (10%), THF) to obtain acid 13.
  • TBDMSCI TBDMSCI
  • NAG-PFGg-SA hen7yl ester 12 For preparation of NAG-am ine 1 1 NAG-amin 5 (0.381 mmol) was O-deacetylated as described for precursor 7 (procedure for 8a,b). Product 11 was dried by two evaporations of toluene on a rotovap and dissolved in DMF (25 mL). Bis-dPEG 5 half benzyl half NHS ester (200 mg, 0.381 mmol) was added to the reaction mixture followed by DIEA (0.079 mL, 0.457 mmol), stirred for 8 h and concentrated on a rotovap at 40°C/oil pump vacuum. Crude product 12 was used in the next step without additional purification. MS: 719.4 [M+l ] + ; 516.4 [product of deglycosylation] 4
  • NAG-L 2 -OBn dry product 12 was dissolved in DMF (5 mL), treated with TBDMSCl (230 mg, 1 .524 mmol) followed by imidazole (156 mg, 2.29 mmol). The reaction mixture was stirred for 10 h, all volatiles were removed on a rotovap at 40°C/oil pump vacuum and the residue was taken in EtOAc (85 mL) and washed with HC1 (1 %), H2O. The aqueous phases were combined and back extracted with EtOAc. The combined organic solutions were dried (Na 2 S0 4 ), concentrated and purified on a column, eluent gradient of MeOH (3-6%) in CHC1 3 . Yield of the benzyl ester 291 mg (80 %). MS: 965.3 [M+NH 4 ] + ;948.0 [M+l ] + ; 516.4 [product of deglycosylation .
  • TMSOTf trimethylsilyl trifliioromethanesulfonate
  • DCF dichloroethane
  • t-butyl I2-hydroxy-4,7, 10-trioxadodecanoate HO-PEG 4 -C0 2 tBu
  • SnCI 4 dichloromethane
  • NAG-L-NHS 18a-e For preparation of NAG-L-NHS 18a-e was used procedure described for 18c below.
  • product 18c an ice cold solution of 10b (614 mg, 0.964 mmol) and NHS (122 mg, 1.061 mmol) in DCM (15 mL) was treated with DCC (219 mg, 1 .061 mmol), stirred for 30 min on ice and 8 h at 20°C. The reaction mixture was cooled to 0°C, DCU was filtered off, the residue was concentrated and dried in vacuo. The crude product was dissolved in DMF to make 0.05 M solution and used without additional purification.
  • Products 18b-e were prepared as described for 18a. c) Formation of 20a-I, 3a-h were acylated with NHS ester of hydroxyl-protected NAG- derivatives 18a-e (DIEA, DMF, 5- 10h) to provide 19a-l. Products 19a-l were than treatedwith 5 equivalents of bis(p-nitrophenyl) carbonate ((PNP) 2 CO) ((PNP) 2 CO, dioxane or DCM, 40-50°C, 15-24h) to yield the O-Acetyl protected PNP carbonate derivatives 20a-l. Products 20a-e were used directly for modification of peptides. The acetyl groups and protective groups 2PhiPr, DMCP, MMT from amino acids were removed post modification during consecutive treatment of DPC with TFA and Et 3 N.
  • NAG(R' R 2 R 3 )-L-AA-PABA 19a-l NAG(R' R 2 R 3 )-L-AA-PABA 19a-l.
  • Product 22e was prepared as described for 22a. Purification was done using HPLC column Nucleodur C- 18, 250 x 4.6, eluent ACN-H2O (0.1 % TFA), ramp 15-30%. MS: 998.1 [M+l] + . The isolated product was desalted on Dowex 1 x8 resin, eluent H 2 0. Yield 40%.
  • Example 2 Linkage of protease cleavable masking agents to amine-containing polymers - formation of p-acylamidobenzyl carbamate linkages.
  • R 1 comprises an ASGPr ligand (either protected or unprotected) or a PEG
  • R 2 is an amphipathic membrane active polyamine
  • AA is a dipeptide (either protected or unprotected)
  • Z is an amine-reactive carbonate.
  • To x mg polymer was added 12* mg of HEPES free base in isotonic glucose.
  • the polymer was modified with 2* mg dipeptide masking agent followed by attachment of siRNA.
  • the polymer-siRNA conjugate was then further modified with 6* to 8x mg dipeptide masking agent.
  • siRNAs had the following sequences:
  • RNA synthesis was performed on solid phase by conventional phosphoramidite chemistry on an AKTA Oligopilot 100 (GE Healthcare, Freiburg, Germany) and controlled pore glass (CPG) as solid support.
  • AKTA Oligopilot 100 GE Healthcare, Freiburg, Germany
  • CPG controlled pore glass
  • Example 4 Administration of RNAi polynucleotides in vivo, and delivery to hepatocytes.
  • DPCs were prepared as described above. Six to eight week old mice (strain C57BL/6 or ICR, -18-20 g each) were obtained from Harlan Sprague Dawley (Indianapolis IN). Mice were housed at least 2 days prior to injection. Feeding was performed ad libitum with Harlan Teklad Rodent Diet (Harlan, Madison WI). DPCs were synthesized as described herein. Conjugate solutions (0.4 mL) were injected by infusion into the tail vein. The compositions were soluble and nonaggregating in physiological conditions. Injection into other vessels, e.g.
  • Wistar Han rats 175-200g were obtained from Charles River (Wilmington, MA). Rats were housed at least 1 week prior to injection. Injection volume for rats was typically 1 ml. Unless indicated otherwise, serum samples were taken and/or liver samples were harvested 48 hours after injection.
  • Serum ApoB levels determination Mice were fasted for 4 h (16 h for rats) before serum collection by submandibular bleeding. For rats blood was collected from the jugular vein. Serum ApoB protein levels were determined by standard sandwich ELISA methods. Briefly, a polyclonal goat anti-mouse ApoB antibody and a rabbit anti-mouse ApoB antibody (Biodesign International) were used as capture and detection antibodies respectively. An HRP-conjugated goat anti-rabbit IgG antibody (Sigma) was applied afterwards to bind the ApoB/antibody complex. Absorbance of tetramethyl-benzidine (TMB, Sigma) colorimetric development was then measured by a Tecan Safire2 (Austria, Europe) microplate reader at 450 nm.
  • TMB tetramethyl-benzidine
  • Plasma Factor VII (F7) activity measurements Plasma samples from animals were prepared by collecting blood (9 volumes) (by submandibular bleeding for mice or from jugular vein for rats) into microcentrifuge tubes containing 0.109 mol/L sodium citrate anticoagulant ( 1 volume) following standard procedures. F7 activity in plasma is measured with a chromogenic method using a BIOPHEN VII kit (Hyphen BioMed/Aniara, Mason, OH) following manufacturer's recommendations. Absorbance of colorimetric development was measured using a Tecan Safire2 microplate reader at 405 nm.
  • Example 5 Delivery of siRNA to liver cells in vivo using a amphipathic membrane active polyacrylate polyamine reversibly modified with dipeptide cleavable masking agents.
  • Polyactylale Aiil-41 58-1 1 1 in 100 niM pH 7.5 HEPES buffer was modified 0.5 wt% with the activated disulfide reagent succinimidyloxycarbonyI-alpha-methyl-alpha(2-pyridyl- dithio)toluene (SMPT) (Pierce) to provide thiol reactive groups for subsequent attachment of siRNA.
  • SMPT activated disulfide reagent
  • the thiol-reactive polymer was then diluted to 5 mg/mL in 60 mg/mL HEPES base.
  • conjugates were further modified by addition of an N-acetylgalactosamine derivative of maleic anhydride ( AG-CDM; Table 5).
  • AG-CDM N-acetylgalactosamine derivative of maleic anhydride
  • NAG-CDM NAG-CDM was lyophilized from a 0.1% aqueous solution of glacial acetic acid. To the dried NAG-CDM was added a solution of polymer. Following complete dissolution of anhydride, the solution was incubated for at least 30 min at RT prior to animal administrati NAG-CDM with the polymer yielded:
  • R is the polymer and Rl comprises a ASGPr ligand (e.g. N-acetylga!actosamine).
  • ASGPr ligand e.g. N-acetylga!actosamine
  • Example 6 siRNA in vivo delivery using NAG/PEG-AA-p-nitrophenyl-carbamate poly(acrylate) DPCs.
  • acetate-protected thiol Factor VII siRNA was added to polymer solution at a polymer to siRNA ratio range of 5-10 to 1.
  • NAG-AA-p-nitrophenyl-carbonate masking reagents were added to 40 mg/mL.
  • the DPC was injected into the tail vein of 20 g ICR mice. 48 hours after injection, a sample of serum was harvested and the levels of fVH were measured.
  • the polymer-conjugated siRNA was injected into the tail vein of 20 gm ICR mice. 48 hours after injection, a sample of serum was harvested and the levels of fVII were measured.
  • Example 7 siRNA in vivo delivery using NAG/PEG-AA-p-nilrophenyl-carbamale polyvinyl ether) DPCs.
  • amino acid protecting groups were removed by TFA and NAG acetate protecting groups were removed by incubation in the presence of a solution of 30 volume % triethylamine, 50% methanol and 20% water.
  • the acetate deprotecting solution was removed by rotary evaporation.
  • the masked polymer was coinjected into mice with cholesterol-ApoB siRNA conjugate.
  • Example 8 In vivo knockdown of endogenous ApoB levels following delivery of ApoB siRNA with melittin delivery peptide in mice, enzymatically cleavable masking agents. Melittin was reversibly modified with the indicated amount of enzymatically cleavable masking agents as described above. 200-300 ⁇ g masked melittin was then co-injected with the 50- 100 jig ApoB siRNA-cholesterol conjugate. Effect on ApoB levels were determined as described above. Peptidase cleavable dipeptide-amidobenzyl carbamate modified melittin was an effective siRNA delivery peptide.
  • D-from melittin petide is preferred in combination with the enzymatically cleavable masking agents. While more peptide was required for the same level of target gene knockdown, because the peptide masking was more stable, the therapeutic index was either not altered or improved (compared to masking of the same peptide with CDM-NAG).
  • Example 9 Tumor Targeting with protease cleavable DPCs.
  • A) Target gene knockdown measurement For all studies presented below an siRNA specific for the Ahal gene transcript, the target gene. An siRNA to the enhanced green fluorescent protein (EGFP) was used as an off-target control.
  • the Ahal siRNA was complementary to a sequence motif in Aha l that is 100% homologous in both the human and mouse gene. Therefore, delivery of Ahal siRNA either into cells of the host or into tumor cells in the human xenograft results in mRNA cleavage and degradation.
  • PCR primers were designed that enabled quantitative measurement of both human Ahal and mouse Aha l mRNA levels in tissue samples that contained a mixed population of cell types.
  • tumors were harvested with some healthy mouse liver tissue attached and were processed in Tri-Reagent (Invitrogen) for total RNA isolation. Both human and mouse Ahal mRNA levels were then measured by qPCR assays, using human Cyc-A and mouse ⁇ -actin as internal reference genes. Ahal mRNA levels in animals from mock-injected animals, or mice that received the off-target control GFP siRNA were considered 100%. Results are expressed as percent of Ahal mRNA level relative to control and are shown in Tables below.
  • HCC Orthotopic hepatocellular carcinoma
  • HegG2, Hep3B, or HuH7 cells hepatocellular carcinoma were co-transfected with 2 expression vectors, pMIR85 a human placental secreted alkaline phosphatase (SEAP) vector and pMIR3 a neomycine/kanamycin-resistance gene vector, to develop cell lines with stable SEAP expressionCell were grown DMEM supplemented with 10% FBS and 300 ug/ml G418), collected, counted, and mixed with matrigel (BD Biosciences) (50% by volume).
  • SEAP human placental secreted alkaline phosphatase
  • pMIR3 a neomycine/kanamycin-resistance gene vector
  • Athymic nude or Scid beige mice were anesthetized with -3% isoflourane and placed in a sternal recumbent position. A small, 1 -2 cm, midline abdominal incision was made just below the xyphoid. Using a moist cotton swab, the left lobe of the liver was gently exteriorized. The left lobe of the liver was gently retracted and a syringe needle was inserted into the middle of the left lobe. The syringe needle was inserted with the bevel down about 0.5 cm just under the capsule of the liver. 10 ⁇ of cell/matrigel mixture, containing 100,000 cells, was injected into the liver using a syringe pump.
  • SEAP-HepG2 cells were injected into athymic nude mice.
  • SEAP-Hep3B and SEAP-HuH7 cells were injected into Scid beige mice.
  • the syringe was then removed from the needle from the liver and a cotton swab was placed over the injection site to prevent leakage of the cells or bleeding.
  • the atrigel/cells mixture formed a mass that was visible and did not disappear after removal of the needle.
  • the liver lobe was then gently placed back into the abdomen and the abdominal wall was closed.
  • Sera were collected once per week after tumor implantation and subjected to SEAP assay to monitor tumor growth. For most studies, tumor mice were used 4-5 weeks after implantation, when tumor measurements are predicted to be around 4-8 mm based on SEAP values.
  • HT29 cells were grown in McCoy's 5a medium supplemented with 10% FBS, collected, counted, and mixed with matrigel (BD Biosciences) (50% by volume).
  • matrigel BD Biosciences
  • Athymic nude mice were anesthetized with ⁇ 3% isoflourane and placed in a sternal recumbent position.
  • a small, 1-2 cm, midline abdominal incision was made just below the xyphoid.
  • Using a moist cotton swab the left lobe of the liver was gently exteriorized. The left lobe of the liver was gently retracted and a syringe needle was inserted into the middle of the left lobe.
  • the syringe needle was inserted with the bevel down about 0.5 cm just under the capsule of the liver. 5 ⁇ of cell/matrigel mixture, containing -40,000 cells, was injected into the liver using a syringe pump. The needle was left in the liver for a few moments (15-20 seconds) to ensure the injection was complete. The syringe was then removed from the liver and a cotton swab was placed over the injection site to prevent leakage of the cells or bleeding. The Matrigel/cells mixture formed a mass that was visible and did not disappear after removal of the needle. The liver lobe was then gently placed back into the abdomen and the abdominal wall was closed. Tumor mice were used 4-5 weeks after implantation. Example 10.
  • mice Ahal were knocked down 70% in response PEG 2 4-Val-Cit-Ant- 129-1-siRNA DPC administration (Table 1).
  • PEG550-CDM disustitited maleic anhydride masking agents
  • endogenous hepatocyte Ahal knockdown was decreased.
  • ALT, AST and BUN levels the PEG 2 4-Val-Cit DPCs were well tolerated and did not exhibit toxicity (Table ).
  • Example 11 Knockdown of targeting gene expression with bispecific antibody (bsAb)- targeted DPCs (2011090701).
  • Ant-129-1 polymer was modified with 5x Dig-PheCit (Dig- FCit) masking agent as described above.
  • siRNA was then attached to the conjugate.
  • the Dig-FCit-Ant- 129-1 -siRNA conjugate was further modified with 8* (wt) PEG, 2 -FCit.
  • Ahal -siRNA (RD-09070) or GFP siRNA (RD-05814) was attached at a 4: 1 polymensiRNA weight ratio.
  • 2 -FCit DPCs were purified on Sephadex G50 spin columns to remove unbound reagents.
  • bsAb Cell targeting bispecific antibodies
  • GPC3 heparan sulfate proteoglycan Glypican-3
  • Dig digoxigenin
  • BsAbs were complexed with modified DPCs at a 1.25: 1 weight ratio to provide an estimated 1 : 1 molar ratio. Complexes were formed in PBS at least 30 minutes prior to delivery.
  • Example 12 Knockdown of targeting gene expression with bispecific antibody (bsAb)- targeted DPCs.
  • DPCs were prepared as above except a) PEG24-FCit was used instead of PEG l 2 -FCit and b) Dig-PEG
  • PEG 24 -FCit DPCs aggregated less than PEGn-FCit DPCs and were smaller and more homogenous.
  • Dig-PEGi2-NHS also contained a longer PEG.
  • DPCs were complexes with bsAb and injected into animals as described above. Serum and tissue harvest was performed either at 24 or 48 hours post-injection. As shown in Table 12, a single dose of DPCs (250 ⁇ g polymer wt.) resulted in human Aha l knockdown of 46-56% 24 hours post injection.
  • Example 13 Targeting DPCs to human colorectal adenocarcinoma metastatic liver tumor tissue by bsAb targeted DPCs.
  • Ant-129-l polymer was modified with 5x molar excess Dig- PEG12-NHS and 8x weight excess PEG 2 -FCit.
  • Ahal siRNA or GFP siRNA was attached to the modified polymer at a 4: 1 polymensiRNA weight ratio.
  • DPCs were purified on a Sephadex G50 spin column to remove unbound reagents.
  • Dig-DPCs were complexed with equimolar amount of IGFI R-Dig bsAb or CD33-Dig bsAb or no bsAb in sterile PBS at least 30 minutes prior to injections
  • Animals containing HT29 tumor cells (human colorectal adenocarcinoma; ATCC Number HTB-38) were injected with the DPCs.
  • HT29 cells overexpress the insulin-like growth factor-1 receptor protein (IGF1 R), and can bind and internalize an IGFI R-Dig bispecific antibody.
  • FCit-DPCs Knockdown of human Aha l in tumor cells was 26-38% (Table 13). Compared to CD -DPCs, FCit-DPCs showed less off target liver Ahal knockdown (78-83%compared to 24-36%). FCit-DPCs also showed diminished liver accumulation compared to CDM-DPCs.
  • Example 14 In vivo knockdown of endogenous Ahal in liver tumor. 400 ⁇ g Lau41648- 106 was modified with 8* (weight) PEGi 2 -ValCit or 16x PEG 24 -PheCit. 100 ⁇ g Ahal siRNA or 100 ⁇ g Eg5 control siRNA was attached to the modified polymer as described above. Animals containing Hep3B-SEAP tumor cells were injected with the DPCs. Serum and tissue samples were collected 48 hours after injection. Knockdown of human Ahal in tumor cells was 26-38%.
  • Example 15 in vivo circulation and tissue targeting of masked polymer.
  • Lau24AB polyacrylate 100 ng
  • was treated with l25 I-Bolton-Hunter (BH) reagent 50 ⁇
  • the labeled polymer was purified in 2 ml Sephadex QEA spin column in water.
  • the solution of labeled polymer was stored at 4°C.
  • the unlabeled polymer was supplemented with l25 I-labeled polymer to inject approx. 1 mg polymer having 0.2 ⁇ per 200 g rat.
  • the mixture of labeled and unlabeled polymers (calculated for ⁇ 3.5 animals) was modified as described above with PEG 2 4-FCit or PEG-CDM (2 mg/ml polyacrylate, 14 mg/ml PEG-CDM reagent, 14 mg/ml NAG-PEG-CDM reagent, 16 mg/ml PEG24-FCit reagent). Incubation time 1 hr. The reaction mix was then diluted with isotonic glucose to yield the injection dose per animal in a volume of 1 ml. 3 animals/group were injected. The animals were bled (0.1 - 0.2 ml) at the given times. The amount of polymer present in the samples was determined by counting in gamma counter. As shown in FIG. 4, polymer modified with the protease cleavable masking agent was cleared less rapidly from serum than polymer masked with the pH labile maleic anhydride masking agent. Increase circulation time is beneficial for targeting to non-liver tissue.
  • Example 16 Amphipathic membrane active polymer syntheses.
  • A is a boc protected ethyl-ethoxy amino acryiate
  • B is a propyl methacrylate
  • C is a RAFT agent CPCPA (4-Cyano-4-(phenylcarbonothioylthio) pentanoic acid) And n and m are integers.
  • A can be also beprotected ethyl, propyl, or butyl amino acryiate.
  • B can be higher hydrophobic (10-24 carbon atoms, C I 8 shown) acryiate, lower hydrophobic (1-6 carbon atoms, C4 shown) acryiate, or a combination of lower an higher hydrophobic acrylates.
  • Copolymers consisting of Amine acrylate/C3 methacrylate were synthesized as follows. The monomers and RAFT agent were weighed and brought up into butyl acetate at the indicated ratios. AIBN (azobis-isobutyronitrile) was added and nitrogen was bubbled through the reaction at RT for l h. The reaction mixture was then placed into an oil bath at 80°C for 15h. The polymer was then precipitated with hexane, and further fractionally precipitated using a DCM/Hexane solvent system (see below). The polymer was then dried under reduced pressure. The polymer was deprotected with 7ml 2M HCI in Acetic Acid for 30min at RT.
  • AIBN azobis-isobutyronitrile
  • the product was purified through column chromatography on 29 cm silica using a 7.5 cm diameter column.
  • the solvent system used was 30% ethyl acetate in hexane. Rf: 0.30. Fractions were collected and solvent was removed using rotary evaporation and high vacuum. BAEEA, was obtained with 74% yield. BAEEA was stored in the freezer.
  • BAEEA Polymer Ant-41658-111 Solutions of AIBN (1.00 mg mL) and RAFT agent (4-Cyano- 4(phenylcarbonothioylthio)pentanoic acid (CPCPA), 10.0 mg/mL) in butyl acetate were prepared. Monomer molar feed ratio was 75 BAEEA : 25 propyl methacrylate (CAS:2210- 28-8) with 0.108 CPCPA RAFT agent and 0.016 AIBN catalyst (0.00562 total mol).
  • CPCPA phenylcarbonothioylthio)pentanoic acid
  • BAEEA (1.09 g, 4.21 mmol) (A), propyl methacrylate (.180 g, 1.41 mmol) (B), CPCPA solution (.170 ml, .00609 mmol) (C), AIBN solution (.150 ml, .000915 mmol), and butyl acetate (5.68 ml) were added to a 20ml glass vial with stirrer bar.
  • the vial was sealed with a rubber cap and the solution was bubbled with nitrogen using a long syringe needle with a second short syringe needle as the outlet for 1 hour.
  • the syringe needles were removed and the system was heated to 80°C for 15 h using an oil bath.
  • Ant-129-1 was made as essentially as described above except the following monomers were used:
  • AIBN initiator
  • BAPA BOC-amino propyl acrylate
  • the product was dried over Na2SC» , gravity filtered, and DCM was evaporated using rotary evaporation.
  • the product was purified through column chromatography on 29 cm silica using a 7.5 cm diameter column.
  • the solvent system used was 30% ethyl acetate in hexane. Rf: 0.30, Fractions were collected and solvent was removed using rotary evaporation and high vacuum. BAPA was obtained with 74% yield.
  • the purified BOC-protected polymer was reacted 2M HCl in Acetic Acid (7 ml) for 0.5 h to remove the BOC protecting groups and produce the amines. 15 mL dH 2 0 were added to the reaction, the solution was transferred to 3500 MW cutoff cellulose tubing, dialyzed against high salt for 24 h, then against dH 2 0 for 18 h. The contents were lyophilized, then dissolved in DI H 2 0 at a concentration of 20 mg/ml . The polymer solution was stored at 2-8°C. v) Synthesis of water-soluble, a phipathic, membrane active polyvinyl ether) polyamine ierpolymers.
  • X mol% amine-protected vinylether e.g., 2-Vinyloxy Ethyl Phthalimide
  • 2-Vinyloxy Ethyl Phthalimide is added to an oven dried round bottom flask under a blanket of nitrogen in anhydrous dichloromethane.
  • Y mol% lower hydrophobic group e.g., propyl, butyl
  • Z mol% higher hydrophobic group e.g., dodecyl, octadecyl
  • the solution is placed in a -50 to -78°C bath, and the 2-vinyloxy ethyl phthalimide is allowed to precipitate.
  • the resulting solid is dissolved in 0.5 mol/L HCl and refluxed for 15-min to form the hydrochloride salt of the polymer, diluted with distilled water, and refluxed for an additional hour.
  • the solution is then neutralized with NaOH, cooled to room temperature (RT), transferred to molecular cellulose tubing, dialyzed against distilled water, and lyophilized.
  • the polymer can be further purified using size exclusion or other chromatography.
  • the molecular weight of the polymers is estimated using columns according to standard procedures, including analytical size-exclusion chromatography and size- exclusion chromatography with multi-angle light scattering (SEC- ALS).
  • Polymer DW1360 An amine/butyl/octadecyl polyvinyl ether) terpolymer, was synthesized from 2-vinyloxy ethyl phthalimide (5 g, 23.02 mmol), butyl vinylether (0.665 g, 6.58 mmol), and octadecyl vinylether (0.488 g, 1.64 mmol) monomers.
  • 2-vinyloxy ethyl phthalimide was added to a 200 mL oven dried round bottom flask containing a magnetic stir bar under a blanket of Argon in 36 mL anhydrous dichloromethane.
  • the polymerization was stopped by the addition of 5 mL of 1 % ammonium hydroxide in methanol. The solvents were then removed by rotary evaporation. The polymer was then dissolved in 30 mL of 1 ,4-dioxane/methanol (2/1). To this solution was added hydrazine (0.147 g, 46 mmol) and the mixture was heated to reflux for 3 h. The solvents were then removed by rotary evaporation and the resulting solid was then brought up in 20 mL of 0.5 mol/L HCI and refluxed for 15 minutes, diluted with 20 mL distilled water, and refluxed for an additional hour. This solution was then neutralized with NaOH, cooled to RT, transferred to 3,500 molecular weight cellulose tubing, dialyzed for 24 h (2 20L) against distilled water, and lyophilized.
  • melittin All melittin peptides were made using peptide synthesis techniques standard in the art. Suitable melittin peptides can be all L-form amino acids, all D-form amino acids (inverso). Independently of L or D form, the melittin peptide sequence can be reversed (retro).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Genetics & Genomics (AREA)
  • Engineering & Computer Science (AREA)
  • Molecular Biology (AREA)
  • Animal Behavior & Ethology (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Biochemistry (AREA)
  • Biophysics (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Epidemiology (AREA)
  • Biotechnology (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Wood Science & Technology (AREA)
  • Zoology (AREA)
  • Biomedical Technology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • General Engineering & Computer Science (AREA)
  • Gastroenterology & Hepatology (AREA)
  • Microbiology (AREA)
  • Physics & Mathematics (AREA)
  • Plant Pathology (AREA)
  • Polymers & Plastics (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Medicinal Preparation (AREA)
  • Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)
  • Peptides Or Proteins (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

La présente invention concerne des compositions pour l'administration de polynucléotides d'ARN interférence (ARNi) à des cellules in vivo. Les compositions comprennent des polyamines actives de membrane bipolaire modifiées de façon réversible avec des agents masquants de dipeptide-amidobenzyl-carbonate clivables par une enzyme. La modification masque l'activité membranaire du polymère tandis que la réversibilité produit une réponse physiologique. Les polyamines modifiées de façon réversible (polyconjugué dynamique ou DPC) sont en outre liés de façon covalente à un polynucléotide d'ARNi ou co-administrés avec un conjugué polynucléotide ARNi ciblé-molécule de ciblage.
EP11853858.6A 2010-12-29 2011-12-28 Conjugués d'administration de polynucléotide in vivo ayant des liaisons sensibles à des enzymes Withdrawn EP2658579A4 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US201061427936P 2010-12-29 2010-12-29
US13/336,028 US8426554B2 (en) 2010-12-29 2011-12-23 In vivo polynucleotide delivery conjugates having enzyme sensitive linkages
PCT/US2011/067588 WO2012092373A2 (fr) 2010-12-29 2011-12-28 Conjugués d'administration de polynucléotide in vivo ayant des liaisons sensibles à des enzymes

Publications (2)

Publication Number Publication Date
EP2658579A2 true EP2658579A2 (fr) 2013-11-06
EP2658579A4 EP2658579A4 (fr) 2015-07-22

Family

ID=46383848

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11853858.6A Withdrawn EP2658579A4 (fr) 2010-12-29 2011-12-28 Conjugués d'administration de polynucléotide in vivo ayant des liaisons sensibles à des enzymes

Country Status (15)

Country Link
EP (1) EP2658579A4 (fr)
JP (1) JP5941926B2 (fr)
KR (1) KR20130136494A (fr)
CN (1) CN103491982B (fr)
AU (1) AU2011352204B2 (fr)
BR (1) BR112013014115A2 (fr)
CA (1) CA2816041C (fr)
CL (2) CL2013001876A1 (fr)
MX (2) MX347298B (fr)
NZ (1) NZ611656A (fr)
PE (1) PE20140198A1 (fr)
RU (1) RU2619453C2 (fr)
SG (1) SG189942A1 (fr)
WO (1) WO2012092373A2 (fr)
ZA (1) ZA201302896B (fr)

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150291958A1 (en) 2012-11-15 2015-10-15 Roche Innovation Center Copenhagen A/S Anti apob antisense conjugate compounds
CN105451743B (zh) * 2013-08-07 2019-11-19 箭头研究公司 用于在活体中递送RNAi触发子至肿瘤细胞的聚偶联物
JOP20210043A1 (ar) 2015-10-01 2017-06-16 Arrowhead Pharmaceuticals Inc تراكيب وأساليب لتثبيط تعبير جيني للـ lpa
MA45328A (fr) 2016-04-01 2019-02-06 Avidity Biosciences Llc Compositions acide nucléique-polypeptide et utilisations de celles-ci
JP2020520981A (ja) 2017-05-24 2020-07-16 ラモット・アット・テル・アビブ・ユニバーシテイ・リミテッドＲａｍｏｔ Ａｔ Ｔｅｌ Ａｖｉｖ Ｕｎｉｖｅｒｓｉｔｙ Ｌｔｄ． プロテアーゼのイメージング／検出のための化学発光プローブ
KR102623786B1 (ko) 2017-12-06 2024-01-11 어비디티 바이오사이언시스 인크. 근위축증 및 근긴장성 이영양증을 치료하는 조성물 및 방법
WO2020139788A2 (fr) * 2018-12-28 2020-07-02 Sirnaomics, Inc. Administration ciblée de molécules thérapeutiques
US11555190B2 (en) 2020-03-19 2023-01-17 Avidity Biosciences, Inc. Compositions and methods of treating Facioscapulohumeral muscular dystrophy
EP4285937A1 (fr) * 2021-01-28 2023-12-06 Nanjing Chempion Biotechnology Co., Ltd. Conjugué et son utilisation
CN117480175A (zh) * 2021-06-24 2024-01-30 东北泰克诺亚奇股份有限公司 荧光探针
KR102712976B1 (ko) * 2021-07-27 2024-10-07 국립안동대학교 산학협력단 등검은말벌 추출물을 유효성분으로 함유하는 혈전증의 예방 또는 치료용 약학적 조성물 및 건강 기능 식품
CN113621003B (zh) * 2021-09-10 2023-02-03 国科温州研究院(温州生物材料与工程研究所) 一种制备有机分子共价修饰的功能化核酸材料的方法及其应用
WO2023043953A1 (fr) 2021-09-16 2023-03-23 Avidity Biosciences, Inc. Compositions et méthodes de traitement d'une dystrophie musculaire facio-scapulo-humérale

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6214345B1 (en) * 1993-05-14 2001-04-10 Bristol-Myers Squibb Co. Lysosomal enzyme-cleavable antitumor drug conjugates
US6180095B1 (en) * 1997-12-17 2001-01-30 Enzon, Inc. Polymeric prodrugs of amino- and hydroxyl-containing bioactive agents
CN1433478A (zh) * 1999-12-30 2003-07-30 诺瓦提斯公司 用于基因治疗的新的胶体合成载体
NZ520458A (en) * 2000-02-24 2005-02-25 Genentech Inc Caspase activated prodrugs therapy
EP1243276A1 (fr) * 2001-03-23 2002-09-25 Franciscus Marinus Hendrikus De Groot Prodrogues activables à séparateurs allongés et multiples
US7091186B2 (en) * 2001-09-24 2006-08-15 Seattle Genetics, Inc. p-Amidobenzylethers in drug delivery agents
US7541330B2 (en) * 2004-06-15 2009-06-02 Kosan Biosciences Incorporated Conjugates with reduced adverse systemic effects
WO2007059404A2 (fr) * 2005-11-10 2007-05-24 Medarex, Inc. Composes et conjugues cytotoxiques
RU2430740C2 (ru) * 2006-08-18 2011-10-10 Ф.Хоффманн-Ля Рош Аг Поликонъюгаты для введения in vivo полинуклеотидов
JP5274461B2 (ja) * 2006-08-18 2013-08-28 アローヘッド リサーチ コーポレイション ポリヌクレオチドのインビボ送達のためのポリ結合体
CA2675014C (fr) * 2007-01-17 2016-03-29 Immunomedics, Inc. Supports polymeres d'agents therapeutiques et fractions de reconnaissance pour un ciblage a base d'anticorps de sites de maladie
TW201004647A (en) * 2008-05-20 2010-02-01 Sigma Tau Ind Farmaceuti Novel dual targeting antitumoural conjugates
US8501930B2 (en) * 2010-12-17 2013-08-06 Arrowhead Madison Inc. Peptide-based in vivo siRNA delivery system

Also Published As

Publication number Publication date
CN103491982B (zh) 2017-09-12
CA2816041C (fr) 2019-01-08
KR20130136494A (ko) 2013-12-12
MX341118B (es) 2016-08-09
CL2015003580A1 (es) 2016-07-15
EP2658579A4 (fr) 2015-07-22
ZA201302896B (en) 2014-07-25
SG189942A1 (en) 2013-06-28
AU2011352204A1 (en) 2013-05-02
JP2014505685A (ja) 2014-03-06
CN103491982A (zh) 2014-01-01
CA2816041A1 (fr) 2012-07-05
CL2013001876A1 (es) 2014-04-11
MX2013007316A (es) 2013-07-29
PE20140198A1 (es) 2014-02-21
AU2011352204B2 (en) 2015-05-21
WO2012092373A3 (fr) 2013-10-24
WO2012092373A2 (fr) 2012-07-05
MX347298B (es) 2017-04-21
NZ611656A (en) 2014-10-31
RU2619453C2 (ru) 2017-05-16
BR112013014115A2 (pt) 2019-09-24
JP5941926B2 (ja) 2016-06-29
RU2013117286A (ru) 2015-03-10

Similar Documents

Publication Publication Date Title
US8426554B2 (en) In vivo polynucleotide delivery conjugates having enzyme sensitive linkages
AU2011352204B2 (en) In vivo polynucleotide delivery conjugates having enzyme sensitive linkages
US10316316B2 (en) Compositions for targeted delivery of siRNA
US9526796B2 (en) Peptide-based in vivo siRNA delivery system
US20150104408A1 (en) Poly(acrylate) Polymers for In Vivo Nucleic Acid Delivery
EP3030244B1 (fr) Polyconjugués pour l'administration de déclencheurs d'arni à des cellules tumorales in vivo
EP2838544A1 (fr) Polymères de poly(acrylate) pour une administration d'acide nucléique in vivo

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20130716

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

R17D Deferred search report published (corrected)

Effective date: 20131024

DAX Request for extension of the european patent (deleted)
A4 Supplementary search report drawn up and despatched

Effective date: 20150618

RIC1 Information provided on ipc code assigned before grant

Ipc: A61K 48/00 20060101AFI20150612BHEP

Ipc: C07C 69/96 20060101ALI20150612BHEP

Ipc: C08G 63/91 20060101ALI20150612BHEP

Ipc: A61K 47/48 20060101ALI20150612BHEP

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: ARROWHEAD RESEARCH CORPORATION

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: ARROWHEAD PHARMACEUTICALS, INC.

17Q First examination report despatched

Effective date: 20170620

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20181218