Patents by Inventor Ravi V. J. Chari

Ravi V. J. Chari 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: 7217819
    Abstract: A cytotoxic agent comprising one or more taxanes linked to a cell binding agent. A therapeutic composition for killing selected cell populations comprising: (A) a cytotoxic amount of one or more taxanes covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier, diluent or excipient. A method for killing selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more taxanes linked to a cell binding agent. Novel sulfur-containing taxanes.
    Type: Grant
    Filed: August 16, 2005
    Date of Patent: May 15, 2007
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Walter A. Blättler
  • 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: 7008942
    Abstract: A cytotoxic agent comprising one or more taxanes linked to a cell binding agent. A therapeutic composition for killing selected cell populations comprising: (A) a cytotoxic amount of one or more taxanes covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier, diluent or excipient. A method for killing selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more taxanes linked to a cell binding agent. Novel sulfur-containing taxanes.
    Type: Grant
    Filed: October 15, 2003
    Date of Patent: March 7, 2006
    Assignee: Immunogen, Inc.
    Inventors: Ravi V. J. Chari, Walter A. Blättler
  • Publication number: 20040235840
    Abstract: New thiol and disulfide-containing maytansinoids bearing a mono or di-alkyl substitution on the &agr;-carbon atom bearing the sulfur atom are disclosed. Also disclosed are methods for the synthesis of these new maytansinoids and methods for the linkage of these new maytansinoids to cell-binding agents. The maytansinoid-cell-binding agent conjugates are useful as therapeutic agents, which are delivered specifically to target cells and are cytotoxic. These conjugates display vastly improved therapeutic efficacy in animal tumor models compared to the previously described agents.
    Type: Application
    Filed: May 20, 2004
    Publication date: November 25, 2004
    Applicant: IMMUNOGEN, INC.
    Inventors: Ravi V.J. Chari, Wayne C. Widdison
  • 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
  • Publication number: 20040109867
    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: October 27, 2003
    Publication date: June 10, 2004
    Applicant: IMMUNOGEN INC.
    Inventors: Robert Yongxin, Ravi V.J. Chari
  • Publication number: 20040087649
    Abstract: A cytotoxic agent comprising one or more taxanes linked to a cell binding agent. A therapeutic composition for killing selected cell populations comprising: (A) a cytotoxic amount of one or more taxanes covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier, diluent or excipient. A method for killing selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more taxanes linked to a cell binding agent. Novel sulfur-containing taxanes.
    Type: Application
    Filed: October 15, 2003
    Publication date: May 6, 2004
    Applicant: IMMUNOGEN INC.
    Inventors: Ravi V.J. Chari, Walter A. Blattler
  • 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
  • Patent number: 6706708
    Abstract: A cytotoxic agent comprising one or more taxanes linked to a cell binding agent. A therapeutic composition for killing selected cell populations comprising: (A) a cytotoxic amount of one or more taxanes covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier, diluent or excipient. A method for killing selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more taxanes linked to a cell binding agent. Novel sulfur-containing taxanes.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: March 16, 2004
    Assignee: Immunogen, Inc.
    Inventors: Ravi V. J. Chari, Walter A. Blättler
  • Publication number: 20040024049
    Abstract: Included within the scope of the present invention are potent taxanes containing a linking group. Also included is a cytotoxic agent comprising one or more taxanes linked to a cell binding agent. A therapeutic composition for inducing cell death in selected cell populations comprising: (A) a cytotoxic amount of one or more taxanes covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier, diluent or excipient is also included. A method for inducing cell death in selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more taxanes linked to a cell binding agent is included as well.
    Type: Application
    Filed: February 21, 2003
    Publication date: February 5, 2004
    Applicant: IMMUNOGEN INC.
    Inventors: Erkan Baloglu, Michael Miller, 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: 6630579
    Abstract: A cytotoxic agent comprising one or more modified doxorubicins/daunorubicin linked to a cell binding agent. A therapeutic composition for killing selected cell populations comprising: (A) a cytotoxic amount of one or more modified doxorubicins/daunorubicins covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier. A method for killing selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more modified doxorubicins/daunorubicins linked to a cell binding agent. Novel sulfur-containing modified doxorubicins/daunorubicins.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: October 7, 2003
    Assignee: Immunogen Inc.
    Inventors: Ravi V. J. Chari, Walter A. Blättler
  • Patent number: 6596757
    Abstract: A cytotoxic agent comprising one or more polyethylene glycol-containing taxanes linked to a cell binding agent. A therapeutic composition for killing selected cell populations comprising: (A) a cytotoxic amount of one or more polyethylene glycol-containing taxanes covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier, diluent or excipient. A method for killing selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more polyethylene glycol-containing taxanes linked to a cell binding agent.
    Type: Grant
    Filed: May 14, 2002
    Date of Patent: July 22, 2003
    Assignee: Immunogen Inc.
    Inventors: Ravi V. J. Chari, Michael Louis Miller
  • 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
  • Publication number: 20030055226
    Abstract: The present invention discloses a one-step process for the production of cytotoxic conjugates of maytansinoids and cell binding agents. Maytansinoids having a disulfide linker that bears a reactive moiety are linked to cell binding agents, such as antibodies, without prior modification of the cell binding agent. These conjugates are useful as therapeutic agents which are delivered specifically to target cells and are cytotoxic.
    Type: Application
    Filed: June 5, 2002
    Publication date: March 20, 2003
    Applicant: IMMUNOGEN, INC.
    Inventors: Ravi V. J. Chari, Wayne C. Widdison
  • Patent number: 6534660
    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: April 5, 2002
    Date of Patent: March 18, 2003
    Assignee: Immunogen, Inc.
    Inventors: Robert Yongxin, Ravi V. J. Chari
  • Publication number: 20030004210
    Abstract: A cytotoxic agent comprising one or more taxanes linked to a cell binding agent. A therapeutic composition for killing selected cell populations comprising: (A) a cytotoxic amount of one or more taxanes covalently bonded to a cell binding agent through a linking group, and (B) a pharmaceutically acceptable carrier, diluent or excipient. A method for killing selected cell populations comprising contacting target cells or tissue containing target cells with an effective amount of a cytotoxic agent comprising one or more taxanes linked to a cell binding agent. Novel sulfur-containing taxanes.
    Type: Application
    Filed: July 31, 2002
    Publication date: January 2, 2003
    Applicant: IMMUNOGEN INC.
    Inventors: Ravi V.J. Chari, Walter A. Blattler
  • Patent number: 6441163
    Abstract: The present invention discloses a one-step process for the production of cytotoxic conjugates of maytansinoids and cell binding agents. Maytansinoids having a disulfide linker that bears a reactive moiety are linked to cell binding agents, such as antibodies, without prior modification of the cell binding agent. These conjugates are useful as therapeutic agents which are delivered specifically to target cells and are cytotoxic.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: August 27, 2002
    Assignee: Immunogen, Inc.
    Inventors: Ravi V. J. Chari, Wayne C. Widdison