Patents by Inventor Robert Yongxin Zhao

Robert Yongxin Zhao 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).

  • Publication number: 20130266596
    Abstract: The invention relates to novel benzodiazepine derivatives with antiproliferative activity and more specifically to novel benzodiazepines of formula (I) and (II), in which the diazepine ring (B) is fused with a heterocyclic ring (CD), wherein the heterocyclic ring is bicyclic or a compound of formula (III), in which the diazepine ring (B) is fused with a heterocyclic ring (C), wherein the heterocyclic ring is monocyclic. The invention provides cytotoxic dimers of these compounds. The invention also provides conjugates of the monomers and the dimers. The invention further provides compositions and methods useful for inhibiting abnormal cell growth or treating a proliferative disorder in a mammal using the compounds or conjugates of the invention. The invention further relates to methods of using the compounds or conjugates for in vitro, in situ, and in vivo diagnosis or treatment of mammalian cells, or associated pathological conditions.
    Type: Application
    Filed: February 22, 2013
    Publication date: October 10, 2013
    Inventors: Wei Li, Nathan Elliott Fishkin, Robert Yongxin Zhao, Michael Louis Miller, Ravi V.J. Chari
  • Publication number: 20130011419
    Abstract: Charged or pro-charged cross-linking moieties and conjugates of cell binding agents and drugs comprising the charged or pro-charged cross-linking moieties and method of making the same.
    Type: Application
    Filed: July 5, 2012
    Publication date: January 10, 2013
    Applicant: ImmunoGen, INC.
    Inventors: Ravi V.J. Chari, Robert Yongxin Zhao, Yelena Kovtun, Rajeeva Singh, Wayne Charles Widdison
  • Patent number: 8236319
    Abstract: Charged or pro-charged cross-linking moieties and conjugates of cell binding agents and drugs comprising the charged or pro-charged cross-linking moieties and method of making the same.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: August 7, 2012
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Robert Yongxin Zhao, Yelena Kovtun, Rajeeva Singh, Wayne Charles Widdison
  • Publication number: 20120165537
    Abstract: Processes for the preparation of charged crosslinkers bearing a sulfonic acid moiety are disclosed. These procedures also optionally include methods to convert the resulting products to substantially a single salt form.
    Type: Application
    Filed: December 8, 2011
    Publication date: June 28, 2012
    Applicant: IMMUNOGEN, INC.
    Inventors: Wei LI, Robert Yongxin ZHAO
  • Patent number: 7906545
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: March 15, 2011
    Assignee: Immunogen Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari
  • Publication number: 20110008373
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Application
    Filed: September 20, 2010
    Publication date: January 13, 2011
    Applicant: IMMUNOGEN, INC.
    Inventors: Robert Yongxin ZHAO, Ravi V.J. CHARI
  • Patent number: 7655660
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Grant
    Filed: January 5, 2007
    Date of Patent: February 2, 2010
    Assignee: Immunogen Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari
  • Patent number: 7655661
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytotoxic drugs in a targeted fashion.
    Type: Grant
    Filed: June 23, 2008
    Date of Patent: February 2, 2010
    Assignee: ImmunoGen Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari
  • Publication number: 20090281158
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Application
    Filed: July 17, 2009
    Publication date: November 12, 2009
    Applicant: IMMUNOGEN, INC.
    Inventors: ROBERT YONGXIN ZHAO, Ravi V.J. Chari
  • Publication number: 20090274713
    Abstract: Charged or pro-charged cross-linking moieties and conjugates of cell binding agents and drugs comprising the charged or pro-charged cross-linking moieties and method of making the same.
    Type: Application
    Filed: April 30, 2009
    Publication date: November 5, 2009
    Applicant: IMMUNOGEN INC.
    Inventors: Ravi V. J. CHARI, Robert Yongxin Zhao, Yelena Kovtun, Rajeeva Singh, Wayne Charles Widdison
  • Publication number: 20080260685
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytotoxic drugs in a targeted fashion.
    Type: Application
    Filed: June 23, 2008
    Publication date: October 23, 2008
    Applicant: ImmunoGen Inc.
    Inventors: Robert Yongxin ZHAO, Ravi V.J. Chari
  • Patent number: 7388026
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Grant
    Filed: September 2, 2005
    Date of Patent: June 17, 2008
    Assignee: Immunogen, Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari
  • Patent number: 7329760
    Abstract: Improved synthesis of seco(?)CBI (5-hydroxy-3-amino-1-[S]-(chloromethyl)-1,2-dihydro-3H-benz(e)indole): and improved syntheses therefrom of a wide variety of CC-1065 analogs that comprise a cyclopropabenzidole (CBI) alkylating moiety, and which are collectively DC1 and its derivatives, for the synthesis of cell-targeted therapeutic agents.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: February 12, 2008
    Assignee: Immunogen Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari
  • Patent number: 7049316
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: May 23, 2006
    Assignee: Immunogen Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari
  • Patent number: 6756397
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Grant
    Filed: April 5, 2002
    Date of Patent: June 29, 2004
    Assignee: Immunogen, Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari
  • Patent number: 6716821
    Abstract: Cytotoxic agents bearing a polyethylene glycol (PEG) linking group having a terminal active ester, cytotoxic conjugates comprising one or more cytotoxic agents linked to a cell-binding agent via PEG linking groups, and methods for producing both are disclosed. A therapeutic composition comprising a therapeutically-effective amount of one of the cytotoxic conjugates of the present invention, and a method of killing selected cell populations comprising contacting target cells, or tissue containing target cells, with an effective amount of one of the cytotoxic conjugates, are also disclosed.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: April 6, 2004
    Assignee: Immunogen Inc.
    Inventors: Robert Yongxin Zhao, Michael Louis Miller, Wayne Charles Widdison, Ravi V. J. Chari
  • Publication number: 20040001838
    Abstract: Cytotoxic agents bearing a polyethylene glycol (PEG) linking group having a terminal active ester, cytotoxic conjugates comprising one or more cytotoxic agents linked to a cell-binding agent via PEG linking groups, and methods for producing both are disclosed. A therapeutic composition comprising a therapeutically-effective amount of one of the cytotoxic conjugates of the present invention, and a method of killing selected cell populations comprising contacting target cells, or tissue containing target cells, with an effective amount of one of the cytotoxic conjugates, are also disclosed.
    Type: Application
    Filed: December 21, 2001
    Publication date: January 1, 2004
    Applicant: ImmunoGen, Inc.
    Inventors: Robert Yongxin Zhao, Michael Louis Miller, Wayne Charles Widdison, Ravi V.J. Chari
  • Publication number: 20030199519
    Abstract: Prodrugs of analogs of the anti-tumor antibiotic CC-1065 having a cleavable protective group such as a piperazino carbamate, a 4-piperidino-piperidino carbamate or a phosphate, in which the protecting group confers enhanced water solubility and stability upon the prodrug, and in which the prodrug also has a moiety, such as a disulfide, that can conjugate to a cell binding reagent such as an antibody. The therapeutic use of such prodrug conjugates is also described; such prodrugs of cytotoxic agents have therapeutic use because they can deliver cytotoxic prodrugs to a specific cell population for enzymatic conversion to cytoxic drugs in a targeted fashion.
    Type: Application
    Filed: April 5, 2002
    Publication date: October 23, 2003
    Applicant: IMMUNOGEN INC.
    Inventors: Robert Yongxin Zhao, Ravi V.J. Chari
  • Publication number: 20030195365
    Abstract: Improved synthesis of seco(−)CBI (5-hydroxy-3-amino-1-[S]-(chloromethyl)-1,2-dihydro-3H-benz(e)indole): 1
    Type: Application
    Filed: October 7, 2002
    Publication date: October 16, 2003
    Applicant: IMMUNOGEN INC.
    Inventors: Robert Yongxin Zhao, Ravi V.J. Chari
  • Patent number: 6586618
    Abstract: Improved synthesis of seco(−)CBI (5-hydroxy-3-amino-1-[S]-(chloromethyl)-1,2-dihydro-3H-benz(e)indole): and improved syntheses therefrom of a wide variety of CC-1065 analogs that comprise a cyclopropabenzidole (CBI) alkylating moiety, and which are collectively DC1 and its derivatives, for the synthesis of cell-targeted therapeutic agents.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: July 1, 2003
    Assignee: Immunogen Inc.
    Inventors: Robert Yongxin Zhao, Ravi V. J. Chari