Patents by Inventor Kazutoshi Takashio

Kazutoshi Takashio has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8940332
    Abstract: A novel podophyllotoxin derivative, which is capable of releasing a drug without depending on biological enzymes and can be expected to have an effective therapeutic effect and is soluble in water has been demanded. A polymer having a polyethyleneglycol structural unit and two or more succinic monoamide structural units, particularly a polymer conjugate of a podophyllotoxin in which a carboxylic acid group of polyethyleneglycol/polyaspartic acid copolymer and a hydroxyl group of podophyllotoxin and linked via an ester bond is provided.
    Type: Grant
    Filed: May 16, 2007
    Date of Patent: January 27, 2015
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Masayuki Kitagawa, Keizou Ishikawa, Keiichirou Yamamoto, Kazutoshi Takashio, Masao Shibata
  • Patent number: 8808749
    Abstract: A polymer conjugate of a physiologically active substance, which enables drug release independent of a biological enzyme and can be expected to have a high therapeutic effect, is demanded.
    Type: Grant
    Filed: May 12, 2010
    Date of Patent: August 19, 2014
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Masayuki Kitagawa, Chieko Seno, Keiko Ebara, Kazutoshi Takashio
  • Patent number: 8334364
    Abstract: [Problems] A derivative of a nucleic acid antimetabolite is demanded which can show a high therapeutic effect at a low dose. [Means For Solving Problems] Disclosed is a high molecular weight derivative of a nucleic acid antimetabolite, which is characterized by comprising a high molecular weight compound comprising a polyethylene glycol moiety and a polymer moiety having a carboxyl group in a side chain and a nucleoside derivative which can act as a nucleic acid antimetabolite, wherein the carboxyl group in the side chain is bound to a hydroxyl group in the nucleoside derivative via an ester bond. Also disclosed is a method for producing the high molecular weight derivative.
    Type: Grant
    Filed: November 1, 2007
    Date of Patent: December 18, 2012
    Assignee: Nipon Kayaku Kabushiki Kaisha
    Inventors: Keiichiro Yamamoto, Kazutoshi Takashio
  • Patent number: 8188222
    Abstract: [Problems] A derivative of a nucleic acid antimetabolite is demanded which can show a higher therapeutic effect at a lower dose. [Means for Solving Problems] Disclosed is a high molecular weight derivative a nucleic acid antimetabolite, which is characterized by comprising a high molecular weight compound comprising a polyethylene glycol moiety and a polymer moiety having a carboxyl group in a side chain and a nucleoside derivative which can act as a nucleic acid antimetabolite, wherein the nucleoside derivative is bound to the carboxyl group in the side chain of the high molecular weight compound via a highly hydrophobic linker.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: May 29, 2012
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Keiichiro Yamamoto, Kazutoshi Takashio
  • Publication number: 20120116051
    Abstract: A polymer conjugate of a physiologically active substance, which enables drug release independent of a biological enzyme and can be expected to have a high therapeutic effect, is demanded.
    Type: Application
    Filed: May 12, 2010
    Publication date: May 10, 2012
    Applicant: NIPPON KAYAKU KABUSHIKI KAISHA
    Inventors: Masayuki Kitagawa, Chieko Seno, Keiko Ebara, Kazutoshi Takashio
  • Patent number: 7700709
    Abstract: A derivative of a cytidine metabolic antagonist which can exert a high therapeutic effect at a low dose. A polymeric derivative of a cytidine metabolic antagonist which comprises a polymeric compound having a polyethylene glycol moiety and a polymer moiety having a carboxyl group in a side chain and a cytidine metabolic antagonist, which has such a structure that the carboxyl group in the side chain of the polymeric compound and an amino group in the cytidine metabolic antagonist are bound together to form an amide bond.
    Type: Grant
    Filed: April 27, 2006
    Date of Patent: April 20, 2010
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Akira Masuda, Takeshi Onda, Hiroko Mashiba, Keiichirou Yamamoto, Kazutoshi Takashio
  • Publication number: 20100029849
    Abstract: [Problems] A derivative of a nucleic acid antimetabolite is demanded which can show a higher therapeutic effect at a lower dose. [Means for Solving Problems] Disclosed is a high molecular weight derivative a nucleic acid antimetabolite, which is characterized by comprising a high molecular weight compound comprising a polyethylene glycol moiety and a polymer moiety having a carboxyl group in a side chain and a nucleoside derivative which can act as a nucleic acid antimetabolite, wherein the nucleoside derivative is bound to the carboxyl group in the side chain of the high molecular weight compound via a highly hydrophobic linker.
    Type: Application
    Filed: November 6, 2007
    Publication date: February 4, 2010
    Inventors: Keiichiro Yamamoto, Kazutoshi Takashio
  • Publication number: 20100004403
    Abstract: A novel derivative of combretastatins which has water solubility and is capable of releasing the drug independent of biological enzymes likely to cause individual differences and whose effective therapeutic effect can be expected has been demanded. A high-molecular weight conjugate of combretastatins, characterized by having a structure in which a hydroxyl group of a combretastatin is linked via an ester bond to a carboxylic acid group of the polymer moiety in a block copolymer of a polyethylene glycol moiety with the polymer moiety having two or more carboxylic acid groups such as polyaspartic acid or polyglutamic acid is provided.
    Type: Application
    Filed: July 13, 2007
    Publication date: January 7, 2010
    Inventors: Masayuki Kitagawa, Keizou Ishikawa, Akira Masuda, Kazutoshi Takashio
  • Publication number: 20090281300
    Abstract: [Problems] A derivative of a nucleic acid antimetabolite is demanded which can show a high therapeutic effect at a low dose. [Means For Solving Problems] Disclosed is a high molecular weight derivative of a nucleic acid antimetabolite, which is characterized by comprising a high molecular weight compound comprising a polyethylene glycol moiety and a polymer moiety having a carboxyl group in a side chain and a nucleoside derivative which can act as a nucleic acid antimetabolite, wherein the carboxyl group in the side chain is bound to a hydroxyl group in the nucleoside derivative via an ester bond. Also disclosed is a method for producing the high molecular weight derivative.
    Type: Application
    Filed: November 1, 2007
    Publication date: November 12, 2009
    Inventors: Keiichiro Yamamoto, Kazutoshi Takashio
  • Publication number: 20090162313
    Abstract: [PROBLEMS] A novel podophyllotoxin derivative, which is capable of releasing a drug without depending on biological enzymes and can be expected to have an effective therapeutic effect and is soluble in water has been demanded. [MEANS FOR SOLVING PROBLEMS] A polymer having a polyethyleneglycol structural unit and two or more succinic monoamide structural units, particularly a polymer conjugate of a podophyllotoxin in which a carboxylic acid group of polyethyleneglycol/polyaspartic acid copolymer and a hydroxyl group of podophyllotoxin and linked via an ester bond is provided.
    Type: Application
    Filed: May 16, 2007
    Publication date: June 25, 2009
    Inventors: Masayuki Kitagawa, Keizou Ishikawa, Keiichirou Yamamoto, Kazutoshi Takashio, Masao Shibata
  • Publication number: 20090012252
    Abstract: [PROBLEMS] To provide a derivative of a cytidine metabolic antagonist which can exert a high therapeutic effect at a low dose. [MEANS FOR SOLVING PROBLEMS] A polymeric derivative of a cytidine metabolic antagonist which comprises a polymeric compound having a polyethylene glycol moiety and a polymer moiety having a carboxyl group in a side chain and a cytidine metabolic antagonist, which has such a structure that the carboxyl group in the side chain of the polymeric compound and an amino group in the cytidine metabolic antagonist are bound together to form an amide bond.
    Type: Application
    Filed: April 27, 2006
    Publication date: January 8, 2009
    Inventors: Akira Masuda, Takeshi Onda, Hiroko Mashiba, Keiichirou Yamamoto, Kazutoshi Takashio