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: 20160222013
    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: January 7, 2016
    Publication date: August 4, 2016
    Inventors: Wei Li, Nathan Elliott Fishkin, Robert Yongxin Zhao, Michael Louis Miller, Ravi V.J. Chari
  • Patent number: 9381256
    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: September 2, 2015
    Date of Patent: July 5, 2016
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Michael Louis Miller, Manami Shizuka
  • Patent number: 9376500
    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: December 3, 2013
    Date of Patent: June 28, 2016
    Assignee: ImmunoGen, Inc.
    Inventors: Brenda A. Kellogg, Rajeeva Singh, Ravi V. J. Chari
  • Publication number: 20160114052
    Abstract: Linkers for binding drugs to cell binding agents are modified to hydrophilic linkers by incorporating a polyethylene glycol spacer. The potency or the efficacy of the cell-binding agent-drug conjugates is surprisingly enhanced several folds in a variety of cancer cell types, including those expressing a low number of antigens on the cell surface or cancer cells that are resistant to treatment. A method for preparing maytansinoids bearing a thioether moiety and a reactive group which allows the maytansinoid to be linked to a cell-binding agent in essentially a single step is also provided.
    Type: Application
    Filed: August 25, 2015
    Publication date: April 28, 2016
    Applicant: IMMUNOGEN, INC.
    Inventors: Rajeeva Singh, Yelena Kovtun, Sharon D. Wilhelm, Ravi V.J. Chari
  • Publication number: 20160108129
    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: September 9, 2015
    Publication date: April 21, 2016
    Inventors: Wei Li, Michael Louis Miller, Nathan Elliott Fishkin, Ravi V.J. Chari
  • Publication number: 20160106863
    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: September 2, 2015
    Publication date: April 21, 2016
    Inventors: Ravi V.J. Chari, Michael Louis Miller, Manami Shizuka
  • Publication number: 20160095938
    Abstract: The invention relates to novel cell-binding agent-cytotoxic agent conjugates, wherein the cell-binding agent (CBA) is covalently linked to the cytotoxic agent through an aldehyde group obtained from oxidation of a 2-hydroxyethylamine moiety on the CBA. The invention also provides methods of preparing the conjugates of the present invention. The invention further provides composition and methods useful for inhibiting abnormal cell growth or treating a proliferative disorder in a mammal using the conjugates of the invention.
    Type: Application
    Filed: September 2, 2015
    Publication date: April 7, 2016
    Inventors: Nathan Elliott Fishkin, Daniel Tavares, Lingyun Rui, Luke B. Harris, Manami Shizuka, Michael Louis Miller, Ravi V.J. Chari
  • Publication number: 20160082114
    Abstract: The invention relates to novel benzodiazepine derivatives with antiproliferative activity and more specifically to novel benzodiazepine compounds of formula (I)-(VI). 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: September 2, 2015
    Publication date: March 24, 2016
    Inventors: Ravi V.J. Chari, Michael Louis Miller, Manami Shizuka
  • Publication number: 20160058882
    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: May 22, 2015
    Publication date: March 3, 2016
    Inventors: Ravi V.J. Chari, Wayne C. Widdison, Sharon D. Wilhelm
  • Patent number: 9265841
    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: June 26, 2014
    Date of Patent: February 23, 2016
    Assignee: ImmunoGen, Inc.
    Inventors: Wei Li, Nathan Elliott Fishkin, Robert Yongxin Zhao, Michael Louis Miller, Ravi V. J. Chari
  • Publication number: 20150352223
    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: May 15, 2015
    Publication date: December 10, 2015
    Inventors: Ravi V.J. Chari, Robert Yongxin Zhao, Yelena Kovtun, Rajeeva Singh, Wayne C. Widdison
  • Publication number: 20150315193
    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: February 13, 2015
    Publication date: November 5, 2015
    Inventors: Wei Li, Michael Louis Miller, Ravi V.J. Chari
  • Patent number: 9169272
    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: October 10, 2014
    Date of Patent: October 27, 2015
    Assignee: ImmunoGen, Inc.
    Inventors: Wei Li, Michael Louis Miller, Nathan Elliott Fishkin, Ravi V. J. Chari
  • Patent number: 9150649
    Abstract: Linkers for binding drugs to cell binding agents are modified to hydrophilic linkers by incorporating a polyethylene glycol spacer. The potency or the efficacy of the cell-binding agent-drug conjugates is surprisingly enhanced several folds in a variety of cancer cell types, including those expressing a low number of antigens on the cell surface or cancer cells that are resistant to treatment. A method for preparing maytansinoids bearing a thioether moiety and a reactive group which allows the maytansinoid to be linked to a cell-binding agent in essentially a single step is also provided.
    Type: Grant
    Filed: October 6, 2009
    Date of Patent: October 6, 2015
    Assignee: ImmunoGen, Inc.
    Inventors: Rajeeva Singh, Yelena Kovtun, Sharon D. Wilhelm, Ravi V. J. Chari
  • Publication number: 20150209444
    Abstract: Conjugates and compounds for making conjugates which are PBD molecules linked via the N10 position are disclosed, along with the use of the conjugates for treating proliferative diseases, including cancer.
    Type: Application
    Filed: November 20, 2014
    Publication date: July 30, 2015
    Applicant: ImmunoGen, Inc.
    Inventors: Ravi V.J. Chari, Michael Louis Miller
  • Patent number: 9090629
    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: Grant
    Filed: November 3, 2011
    Date of Patent: July 28, 2015
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Wayne C. Widdison, Sharon D. Wilhelm
  • Patent number: 9061995
    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: November 14, 2013
    Date of Patent: June 23, 2015
    Assignee: ImmunoGen, Inc.
    Inventors: Ravi V. J. Chari, Robert Yongxin Zhao, Yelena Kovtun, Rajeeva Singh, Wayne C. Widdison
  • Publication number: 20150110816
    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: June 4, 2014
    Publication date: April 23, 2015
    Applicants: GENENTECH, INC., IMMUNOGEN INC.
    Inventors: Walter BLATTLER, Ravi V.J. CHARI, Mark SLIWKOWSKI, Sharon ERICKSON, Ralph SCHWALL
  • Publication number: 20150099874
    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: October 10, 2014
    Publication date: April 9, 2015
    Inventors: Wei Li, Michael Louis Miller, Nathan Elliott Fishkin, Ravi V.J. Chari
  • Publication number: 20150071949
    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: Application
    Filed: August 14, 2014
    Publication date: March 12, 2015
    Inventors: Ravi V.J. Chari, Wayne C. Widdison