Polymer nanoparticle composition for inducing immunity and preparation method therefor

A method for preparing a composition for inducing immunity to an active ingredient, comprising

• (a) mixing a nucleic acid as the active ingredient, a cationic compound represented by the following Formula 1, an A-B type block copolymer including a hydrophilic A block of alkylene glycol and a hydrophobic B block of polyester as an amphiphilic block copolymer and a salt of polylactic acid with a solvent which is an aqueous solution, a water-miscible organic solvent or a combination thereof;
• and
• (b) adding an aqueous solvent to the mixture of step (a) and mixing them,
• wherein a mixing amount of the cationic compound is 2 to 15 parts by weight, a mixing amount of the amphiphilic block copolymer is 15 to 50 parts by weight, and a mixing amount of the salt of polylactic acid is 5 to 30 parts by weight, based on 1 part by weight of the active ingredient;
• wherein the active ingredient is entrapped in a nanoparticle structure of the amphiphilic block copolymer and the salt of polylactic acid;
• wherein the composition is suitable for delivering the active ingredient to the spleen efficiently;
• and
• wherein the composition is suitable for treating cancer by inducing immunity to the active ingredient:
• in Formula 1,
• each of n and m is independently 1 to 9, and 2≤n+m≤10,
• each of a and b is 2 to 4,
• each of R1 and R2 is independently selected from the group consisting of lauryl, myristyl, palmityl, stearyl, arachidyl, behenyl, lignoceryl, cerotyl, myristoleyl, palmitoleyl, sapienyl, oleyl, linoleyl, arachidonyl, eicosapentaenyl, erucyl, docosahexaenyl and cerotyl.

A method for treating cancer by efficiently delivering a nucleic acid to the spleen and inducing immunity to a tumor antigen, comprising administering to a subject a composition which comprises:

• a nucleic acid that expresses a tumor antigen;
• a cationic compound represented by the following Formula 1;
• an A-B type block copolymer including a hydrophilic A block of alkylene glycol and a hydrophobic B block of polyester as an amphiphilic block copolymer;
• and
• a salt of polylactic acid,
• wherein a content of the cationic compound is 2 to 15 parts by weight, a content of the amphiphilic block copolymer is 15 to 50 parts by weight, and a content of the salt of polylactic acid is 5 to 30 parts by weight, based on 1 part by weight of the nucleic acid;
• wherein the nucleic acid is entrapped in a nanoparticle structure of the amphiphilic block copolymer and the salt of polylactic acid:
• in Formula 1,
• each of n and m is independently 1 to 9, and 2≤n+m≤10,
• each of a and b is 2 to 4,
• each of R1 and R2 is independently selected from the group consisting of lauryl, myristyl, palmityl, stearyl, arachidyl, behenyl, lignoceryl, cerotyl, myristoleyl, palmitoleyl, sapienyl, oleyl, linoleyl, arachidonyl, eicosapentaenyl, erucyl, docosahexaenyl and cerotyl.