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).

  • Publication number: 20150030616
    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: June 26, 2014
    Publication date: January 29, 2015
    Inventors: Wei Li, Nathan Elliott Fishkin, Robert Yongxin Zhao, Michael Louis Miller, Ravi V.J. Chari
  • Patent number: 8889669
    Abstract: The invention relates to novel benzodiazepine derivatives with antiproliferative activity and more specifically to novel benzodiazepine compounds of formula (I)-(VII). The invention also provides conjugates of the benzodiazepine compounds linked to a cell-binding agent. 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.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: November 18, 2014
    Assignee: ImmunoGen, Inc.
    Inventors: Wei Li, Michael Louis Miller, Nathan Elliott Fishkin, Ravi V. J. Chari
  • Patent number: 8841425
    Abstract: New thiol and disulfide-containing maytansinoids bearing a mono or di-alkyl substitution on the ?-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: Grant
    Filed: March 9, 2011
    Date of Patent: September 23, 2014
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Wayne C. Widdison
  • Patent number: 8809320
    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: Grant
    Filed: February 22, 2013
    Date of Patent: August 19, 2014
    Assignee: ImmunoGen, Inc.
    Inventors: Wei Li, Nathan Elliott Fishkin, Robert Yongxin Zhao, Michael Louis Miller, Ravi V. J. Chari
  • Patent number: 8802667
    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: Grant
    Filed: March 14, 2013
    Date of Patent: August 12, 2014
    Assignee: ImmunoGen, Inc.
    Inventors: Wei Li, Nathan Elliott Fishkin, Robert Yongxin Zhao, Michael Louis Miller, Ravi V. J. Chari
  • Publication number: 20140212411
    Abstract: The application concerns methods of treatment using anti-ErbB receptor antibody-maytansinoid conjugates, and articles of manufacture suitable for use in such methods. In particular, the invention concerns ErbB receptor-directed cancer therapies, using anti-ErbB receptor antibody-maytansinoid conjugates.
    Type: Application
    Filed: September 19, 2013
    Publication date: July 31, 2014
    Applicants: GENENTECH, INC., IMMUNOGEN, INC.
    Inventors: Walter BLATTLER, Ralph SCHWALL, Mark SLIWKOWSKI, Sharon ERICKSON, Ravi V.J. CHARI
  • Patent number: 8765740
    Abstract: The invention relates to novel benzodiazepine derivatives with antiproliferative activity and more specifically to novel benzodiazepine compounds of formula (I)-(VII). The invention also provides conjugates of the benzodiazepine compounds linked to a cell-binding agent. 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.
    Type: Grant
    Filed: February 15, 2012
    Date of Patent: July 1, 2014
    Assignee: ImmunoGen, Inc.
    Inventors: Wei Li, Michael Miller, Nathan Fishkin, Ravi V. J. Chari
  • Publication number: 20140178416
    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: November 14, 2013
    Publication date: June 26, 2014
    Applicant: IMMUNOGEN, INC.
    Inventors: Ravi V.J. Chari, Robert Yongxin Zhao, Yelena Kovtun, Rajeeva Singh, Wayne C. Widdison
  • Publication number: 20140179906
    Abstract: This invention describes a method of conjugating a cell binding agent such as an antibody with an effector group (e.g., a cytotoxic agent) or a reporter group (e.g., a radionuclide), whereby the reporter or effector group is first reacted with a bifunctional linker and the mixture is then used without purification for the conjugation reaction with the cell binding agent. The method described in this invention is advantageous for preparation of stably-linked conjugates of cell binding agents, such as antibodies with effector or reporter groups.
    Type: Application
    Filed: December 3, 2013
    Publication date: June 26, 2014
    Applicant: ImmunoGen, Inc.
    Inventors: Brenda A. KELLOGG, Rajeeva SINGH, Ravi V. J. CHARI
  • Publication number: 20140154804
    Abstract: The present invention discloses a method for targeting maytansinoids to a selected cell population, the method comprising contacting a cell population or tissue suspected of containing the selected cell population with a cell-binding agent maytansinoid conjugate, wherein one or more maytansinoids is covalently linked to the cell-binding agent via a non-cleavable linker and the cell-binding agent binds to cells of the selected cell population.
    Type: Application
    Filed: February 4, 2014
    Publication date: June 5, 2014
    Applicant: IMMUNOGEN INC
    Inventors: Ravi V.J. CHARI, Walter A. BLATTLER
  • Patent number: 8685920
    Abstract: The present invention discloses a method for targeting maytansinoids to a selected cell population, the method comprising contacting a cell population or tissue suspected of containing the selected cell population with a cell-binding agent maytansinoid conjugate, wherein one or more maytansinoids is covalently linked to the cell-binding agent via a non-cleavable linker and the cell-binding agent binds to cells of the selected cell population.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: April 1, 2014
    Assignee: Immunogen Inc.
    Inventors: Ravi V. J. Chari, Wayne C. Widdison
  • Publication number: 20140088089
    Abstract: The invention relates to novel benzodiazepine derivatives with antiproliferative activity and more specifically to novel benzodiazepine compounds, such as those in formulas (V)-(VII). The invention also provides conjugates of the benzodiazepine compounds linked to a cell-binding agent. 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 present invention is further directed to methods of preparing a conjugate of a cell-binding agent and a cytotoxic compound. The methods comprise the use of an imine reactive compound to enable efficient conjugations of cytotoxic compounds with cell binding agents.
    Type: Application
    Filed: February 15, 2012
    Publication date: March 27, 2014
    Applicant: ImmunoGen, INC.
    Inventor: Ravi V.J. Chari
  • Patent number: 8624003
    Abstract: This invention describes a method of conjugating a cell binding agent such as an antibody with an effector group (e.g., a cytotoxic agent) or a reporter group (e.g., a radionuclide), whereby the reporter or effector group is first reacted with a bifunctional linker and the mixture is then used without purification for the conjugation reaction with the cell binding agent. The method described in this invention is advantageous for preparation of stably-linked conjugates of cell binding agents, such as antibodies with effector or reporter groups. This conjugation method provides in high yields conjugates of high purity and homogeneity that are without inter-chain cross-linking and inactivated linker residues.
    Type: Grant
    Filed: June 3, 2010
    Date of Patent: January 7, 2014
    Assignee: ImmunoGen, Inc.
    Inventors: Brenda A. Kellogg, Rajeeva Singh, Ravi V. J. Chari
  • Patent number: 8613930
    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: July 5, 2012
    Date of Patent: December 24, 2013
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Robert Yongxin Zhao, Yelena Kovtun, Rajeeva Singh, Wayne Charles Widdison
  • Publication number: 20130323268
    Abstract: New ansamitocin derivatives bearing a linking group are disclosed. Also disclosed are methods for the synthesis of these new ansamitocin derivatives and methods for their linkage to cell-binding agents. The ansamitocin derivative-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: November 3, 2011
    Publication date: December 5, 2013
    Applicant: IMMUNOGEN, INC.
    Inventors: Ravi V.J. Chari, Wayne C. Widdison, Sharon D. Wilhelm
  • Publication number: 20130302357
    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: March 14, 2013
    Publication date: November 14, 2013
    Inventors: Wei Li, Nathan Elliott Fishkin, Robert Yongxin Zhao, Michael Louis Miller, Ravi V.J. Chari
  • Publication number: 20130302359
    Abstract: The invention relates to novel benzodiazepine derivatives with antiproliferative activity and more specifically to novel benzodiazepine compounds of formula (I)-(VII). The invention also provides conjugates of the benzodiazepine compounds linked to a cell-binding agent. 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.
    Type: Application
    Filed: March 14, 2013
    Publication date: November 14, 2013
    Inventors: Wei Li, Michael Louis Miller, Nathan Elliott Fishkin, Ravi V.J. Chari
  • 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
  • Patent number: 8435528
    Abstract: New thiol and disulfide-containing maytansinoids bearing a mono or di-alkyl substitution on the ?-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: Grant
    Filed: July 16, 2007
    Date of Patent: May 7, 2013
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Wayne C. Widdison
  • Patent number: RE44704
    Abstract: The present invention is based on the discovery that the administration of at least one immunoconjugate and at least one chemotherapeutic agent provides an unexpectedly superior treatment for cancer. The present invention is directed to compositions comprising at least one immunoconjugate and at least one chemotherapeutic agent and to methods of treating cancer using at least one immunoconjugate and at least one chemotherapeutic agent. The present invention also provides methods of modulating the growth of selected cell populations, such as cancer cells, by administering a therapeutically effective amount of at least one chemotherapeutic agent and at least one immunoconjugate.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: January 14, 2014
    Assignee: Immunogen Inc.
    Inventors: Ravi V. J. Chari, Walter A. Blättler