Abstract: A poly-ion complex micelle comprising: a block copolymer having a hydrophilic block portion, a cationic hydrophobic block portion and a crosslinking block portion positioned between the hydrophilic block and the cationic hydrophobic block, and an anionic molecule drug encapsulated by the block copolymer, wherein the crosslinking block has a hydrazone bond, the block copolymer comprises the first block copolymer chain and the second block copolymer chain, the first block copolymer chain and the second block copolymer chain crosslinked to each other in the crosslinking block portion, the hydrophilic block portion comprises the first hydrophilic block of the first block copolymer chain and the second hydrophilic block of the second block copolymer chain, and the cationic hydrophobic block portion comprises the first cationic hydrophobic block of the first block copolymer chain.

Abstract: A unit-type polyion complex for use in delivering nucleic acid to a target site in a patient includes one or more molecules of a block copolymer having a poly(ethylene glycol) segment and a cationic poly(amino acid) segment and one or more molecules of a nucleic acid. A total quantity of positive charges derived from side chains of the cationic poly(amino acid) segment of the block copolymer in the unit-type polyion complex is not offset by a total quantity of negative charges derived from the nucleic acid. Furthermore, the nucleic acid has a strand length of 10-50 bases, the molecular weight of the poly(ethylene glycol) segment is 40×103 or more, and the block copolymer has a binding constant (Ka) for the nucleic acid of 3.0×105 or more.

Abstract: The present invention provides a polyion complex micelle including an antisense oligonucleotide and a block copolymer of a cationic polymer and a PEG block having a number average molecular weight of 3 kDa to 10 kDa.

Abstract: A unit structure-type pharmaceutical composition includes a single nucleic acid, such as an antisense nucleic acid, electrostatically bound to a single block copolymer having a cationic polyamino acid segment and a hydrophilic polymer chain segment. The negative charges of the nucleic acid are counterbalanced, at least substantially, by the positive charges of the cationic polyamino acid segment such that the pharmaceutical composition is electrically neutral or nearly electrically neutral. Further, the nucleic acid is covered with the hydrophilic polymer chain segment. The block copolymer thereby improves the blood retention capability of the nucleic acids.

Abstract: A unit-type polyion complex for use in delivering nucleic acid to a target site in a patient includes one or more molecules of a block copolymer having a poly(ethylene glycol) segment and a cationic poly(amino acid) segment and one or more molecules of a nucleic acid. A total quantity of positive charges derived from side chains of the cationic poly(amino acid) segment of the block copolymer in the unit-type polyion complex is not offset by a total quantity of negative charges derived from the nucleic acid. Furthermore, the nucleic acid has a strand length of 10-50 bases, the molecular weight of the poly(ethylene glycol) segment is 40×103 or more, and the block copolymer has a binding constant (Ka) for the nucleic acid of 3.0×105 or more.

Abstract: The problem addressed by the present invention is to develop a pharmaceutical having therapeutic efficacy against epirubicin-resistant tumors. The present invention provides a micelle having an anti-cancer agent disposed inside the core of the micelle formed by an epirubicin-conjugated copolymer.

Abstract: A unit structure consists of a single nucleic acid having a length of 10 to 30 bases, and a single block copolymer having a cationic polyamino acid segment and a hydrophilic polymer chain segment. In this unit structure: (i) a difference between a total of positive charges derived from cationic groups of the cationic polyamino acid segment and a total of negative charges derived from the nucleic acid in the unit structure falls within a range of ±10% of the total of the negative charges derived from the nucleic acid, (ii) the hydrophilic polymer chain segment comprises polyethylene glycol, (iii) the polyethylene glycol has a radius of inertia (Rg) equal to or longer than the length of the nucleic acid, and (iv) the cationic polyamino acid segment is bound to the nucleic acid via electrostatic bonds.

Abstract: A unit structure-type pharmaceutical composition includes a single nucleic acid, such as an antisense nucleic acid, electrostatically bound to a single block copolymer having a cationic polyamino acid segment and a hydrophilic polymer chain segment. The negative charges of the nucleic acid are counterbalanced, at least substantially, by the positive charges of the cationic polyamino acid segment such that the pharmaceutical composition is electrically neutral or nearly electrically neutral. Further, the nucleic acid is covered with the hydrophilic polymer chain segment. The block copolymer thereby improves the blood retention capability of the nucleic acids.

Abstract: A unit structure-type pharmaceutical composition includes at least one nucleic acid, such as siRNA, electrostatically bound to at least one block copolymer having a cationic polyamino acid segment and a hydrophilic polymer chain segment. The negative charge(s) of the nucleic acid are counterbalanced, at least substantially, by the positive charge(s) of the cationic polyamino acid segment such that the pharmaceutical composition is electrically neutral or nearly electrically neutral. Further, the nucleic acid is covered with the hydrophilic polymer chain segment(s). The at least one block copolymer thereby improves the blood retention capability of the nucleic acid(s).

Abstract: The problem addressed by the present invention is to develop a pharmaceutical having therapeutic efficacy against epirubicin-resistant tumors. The present invention provides a micelle having an anti-cancer agent disposed inside the core of the micelle formed by an epirubicin-conjugated copolymer.

Abstract: A composition of matter for use in encapsulating a drug is expressed by formula (1) or formula (2): wherein R1 and R2 are each independently a hydrogen atom or a substituted or unsubstituted, linear or branched alkyl group having 1 to 12 carbon atoms; A is a hydrophilic polymer chain; L1 and L3 are each a linking group; B is a cation-containing group; R3 is a side chain of an amino acid; z is an integer of 5 to 500; x is an integer of 40% or more of z; y is 0 or a positive integer; z-x-y is 0 or a positive integer; p is an integer of 1 to 10; and q is an integer of 1 to 10.

Abstract: A unit structure-type pharmaceutical composition includes at least one nucleic acid, such as siRNA, electrostatically bound to at least one block copolymer having a cationic polyamino acid segment and a hydrophilic polymer chain segment. The negative charge(s) of the nucleic acid are counterbalanced, at least substantially, by the positive charge(s) of the cationic polyamino acid segment such that the pharmaceutical composition is electrically neutral or nearly electrically neutral. Further, the nucleic acid is covered with the hydrophilic polymer chain segment(s). The at least one block copolymer thereby improves the blood retention capability of the nucleic acid(s).

Abstract: A composition of matter for use in encapsulating a drug is expressed by formula (1) or formula (2): wherein R1 and R2 are each independently a hydrogen atom or a substituted or unsubstituted, linear or branched alkyl group having 1 to 12 carbon atoms; A is a hydrophilic polymer chain; L1 and L3 are each a linking group; B is a cation-containing group; R3 is a side chain of an amino acid; z is an integer of 5 to 500; x is an integer of 40% or more of z; y is 0 or a positive integer; z-x-y is 0 or a positive integer; p is an integer of 1 to 10; and q is an integer of 1 to 10.

Abstract: The invention provides block copolymers formed of poly(ethylene glycol) segments and poly(amino acid derivative) segments having side chains of at least one kind of specific amine residue. The invention also provides polyion complexes of such copolymers with polynucleotides and the like. These block copolymers are useful as carriers for in vivo delivery of active substances such as DNA.

Abstract: The present invention discloses a vesicle which is excellent in structure stability and environmental responsiveness and also can be produced by a simple operation. More particularly, the present invention discloses a vesicle comprising a membrane formed of a first block copolymer containing a non-chargeable hydrophilic segment and a chargeable segment, and a second block copolymer containing a non-chargeable hydrophilic segment and a chargeable segment having an electric charge which is opposite to that of the chargeable segment of the first block copolymer.

Abstract: Disclosed is a composition for the delivery of nucleic acid to target cells or tissues, which comprises a polycationically charged polymer as a carrier of nucleic acid. The polycationically charged polymer is a polymer which may comprise a charged polymer segment having a main chain based on poly(amino acid), polysaccharide, polyester, polyether, polyurethane or vinyl polymer and having, as a side chain, a group of formula —NH—(CH2)a—(NH(CH2)2)e—NH2 (wherein a and e independently denote an integer of 1 to 5) which is connected to the main chain either directly or via a linker. The disclosed composition has low toxicity, and has a high efficiency in introducing nucleic acid into cells.

Abstract: The invention provides block copolymers formed of poly(ethylene glycol) segments and poly(amino acid derivative) segments having side chains of at least one kind of specific amine residue. The invention also provides polyion complexes of such copolymers with polynucleotides and the like. These block copolymers are useful as carriers for in vivo delivery of active substances such as DNA.

Abstract: The invention provides block copolymers formed of poly(ethylene glycol) segments and poly(amino acid derivative) segments having side chains of at least one kind of specific amine residue. The invention also provides polyion complexes of such copolymers with polynucleotides and the like. These block copolymers are useful as carriers for in vivo delivery of active substances such as DNA.

Abstract: The present invention discloses a vesicle which is excellent in structure stability and environmental responsiveness and also can be produced by a simple operation. More particularly, the present invention discloses a vesicle comprising a membrane formed of a first block copolymer containing a non-chargeable hydrophilic segment and a chargeable segment, and a second block copolymer containing a non-chargeable hydrophilic segment and a chargeable segment having an electric charge which is opposite to that of the chargeable segment of the first block copolymer.

Abstract: A composition for the delivery of nucleic acid to target cells or tissues, which comprises polycationically charged polymer as a carrier of nucleic acid is provided. Said polycationically charged polymer is a polymer which may comprise a charged polymer segment having a main chain based on poly(amino acid), polysaccharide, polyester, polyether, polyurethane or vinyl polymer and having, as a side chain, a group of formula —NH—(CH2)a—(NH(CH2)2)e—NH2 (wherein a and e independently denote an integer of 1 to 5) which is connected to said main chain either directly or via a linker. This composition is low-toxic, and has a high efficiency in introducing nucleic acid into cells.