Patents by Inventor Samuel Zalipsky

Samuel Zalipsky 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: 6056973
    Abstract: Reagents for use in preparing a therapeutic liposome composition sensitized to a target cell are described. The reagents include a liposomal composition composed of pre-formed liposomes having an entrapped therapeutic agent and a plurality of targeting conjugates composed of a lipid, a hydrophilic polymer and a targeting ligand. The therapeutic, target-cell sensitized liposome composition is formed by incubating the liposomal composition with a selected conjugate.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: May 2, 2000
    Assignee: Sequus Pharmaceuticals, Inc.
    Inventors: Theresa M. Allen, Paul Uster, Francis J. Martin, Samuel Zalipsky
  • Patent number: 6051251
    Abstract: A method for loading a therapeutic compound having a cis diol moiety into pre-formed liposomes is described. The method includes adding to a suspension of liposomes (i) the compound to be loaded into the liposomes and (ii) a boronic acid compound, thereby achieving accumulation of the compound within the liposomes.
    Type: Grant
    Filed: November 19, 1998
    Date of Patent: April 18, 2000
    Assignee: Alza Corporation
    Inventors: Samuel Zalipsky, Paul S. Uster, George Z. Zhu
  • Patent number: 6043094
    Abstract: A method of liposome-based therapy for a mammalian subject is disclosed. The method uses liposomes with outer surfaces that contain an affinity moiety effective to bind specifically to a biological surface at which the therapy is aimed, and a hydrophilic polymer coating effective to shield the affinity moiety from interaction with the target surface. The hydrophilic polymer coating is made up of polymer chains covalently linked to surface lipid components in the liposomes through releasable linkages. After a desired liposome biodistribution is achieved, a releasing agent is administered to cause cleaving of a substantial portion of the releasable linkages in the liposomes, to expose the affinity agent to the target surface.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: March 28, 2000
    Assignee: Sequus Pharmaceuticals, Inc.
    Inventors: Francis J. Martin, Samuel Zalipsky, Shi Kun Huang
  • Patent number: 5972379
    Abstract: A liposome composition for treating a bacterial infection is described. The composition includes liposomes having a surface coating of hydrophilic polymer chains and an entrapped drug-conjugate composed of ciprofloxacin conjugated to an amino acid.
    Type: Grant
    Filed: April 2, 1998
    Date of Patent: October 26, 1999
    Assignee: Sequus Pharmaceuticals, Inc.
    Inventors: Luke S. S. Guo, Josh Gittelman, Samuel Zalipsky, Francis J. Martin
  • Patent number: 5891468
    Abstract: A fusogenic liposome composition for delivering a liposome-entrapped compound into the cytoplasm of a target cell is described. The liposomes have an outer surface coating of chemically releasable hydrophilic polymer chains which shield hydrophobic polymers on the liposome outer surface. Release of the hydrophilic polymer chains exposes the hydrophobic polymers for interaction with outer cell membranes of the target cells to promote fusion of the liposome with the target cells. Also disclosed is a method for using the composition to deliver a compound to target cells, and a method for selecting suitable hydrophobic polymers for use in the composition.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: April 6, 1999
    Assignee: SEQUUS Pharmaceuticals, Inc.
    Inventors: Francis J. Martin, Samuel Zalipsky
  • Patent number: 5631018
    Abstract: A lipid-polymer conjugate for use in forming long-circulating liposomes is disclosed. The conjugate includes a vesicle-forming lipid having covalently attached to its polar head group, one of the polymers: polyvinylpyrrolidone, polyvinylmethylether, polyhydroxypropyl methacrylate, polyhydroxypropylmethacrylamide, polyhydroxyethyl acrylate, polymethacrylamide, polydimethylacrylamide, polymethyloxazoline, polyethyloxazoline, polyhydroxyethyloxazoline, polyhydroxypropyloxazoline, or polyaspartamide. A method for preparing liposomes containing the lipid-polymer conjugate is also disclosed.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: May 20, 1997
    Assignee: Sequus Pharmaceuticals, Inc.
    Inventors: Samuel Zalipsky, Martin C. Woodle, Danilo D. Lasic, Francis J. Martin
  • Patent number: 5545698
    Abstract: The present invention pertains to polyethylene glycol (PEG) derivatized graft supports, to methods for making these supports and to methods of using the supports to synthesize peptides by solid-phase synthesis techniques. The PEG-graft supports of this invention comprise functionalized PEG derivatives which are covalently attached to solid supports, such as polystyrene.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: August 13, 1996
    Assignee: University of Minnesota
    Inventors: George Barany, Fernando Albericio, Nuria A. Sol e, Jane Chang, Samuel Zalipsky
  • Patent number: 5534259
    Abstract: A composition of polymer-coated particles, and a polymer compound used in forming the particles are disclosed. The polymer compound is composed of a hydrophilic polymer attached to a lipophilic moiety through a linking segment which contains chemical groups through which the compound can be crosslinked to other such compounds. The particles in the composition are prepared by forming lipid structures containing ordered arrays of the polymer compounds, and crosslinking the compounds through their chemical groups. The particles are used for parenteral administration of a pharmaceutical compound which is entrapped in the particles.
    Type: Grant
    Filed: July 8, 1993
    Date of Patent: July 9, 1996
    Assignee: Liposome Technology, Inc.
    Inventors: Samuel Zalipsky, Francis J. Martin
  • Patent number: 5455027
    Abstract: Copolymers of poly(alkylene oxides) and amino acids or peptide sequences are disclosed, which amino acids or peptide sequences have pendant functional groups that are capable of being conjugated with pharmaceutically active compounds for drug delivery systems and cross-linked to form polymer matrices functional as hydrogel membranes. The copolymers can also be formed into conductive materials. Methods are also disclosed for preparing the polymers and forming the drug conjugates, hydrogel membranes and conductive materials.
    Type: Grant
    Filed: February 25, 1993
    Date of Patent: October 3, 1995
    Assignee: Enzon, Inc.
    Inventors: Samuel Zalipsky, Durgadas Bolikal, Aruna Nathan, Joachim B. Kohn
  • Patent number: 5395619
    Abstract: A lipid-polymer conjugate for use in forming long-circulating liposomes is disclosed. The conjugate includes a vesicle-forming lipid having covalently attached to its polar head group, one of the polymers: polyvinylpyrrolidone, polyvinylmethylether, polyhydroxypropyl methacrylate, polyhydroxypropylmethacrylamide, polyhydroxyethyl acrylate, polymethacrylamide, polydimethylacrylamide, polymethyloxazoline, polyethyloxazoline, polyhydroxyethyloxazoline, polyhydroxypropyloxazoline, or polyaspartamide. A method for preparing liposomes containing the lipid-polymer conjugate is also disclosed.
    Type: Grant
    Filed: March 3, 1993
    Date of Patent: March 7, 1995
    Assignee: Liposome Technology, Inc.
    Inventors: Samuel Zalipsky, Martin C. Woodle, Danilo D. Lasic, Francis J. Martin
  • Patent number: 5235028
    Abstract: The present invention pertains to polyethylene glycol (PEG) derivatized graft supports, to methods for making these supports and to methods of using the supports to synthesize peptides by solid-phase synthesis techniques. The PEG-graft supports of this invention comprise functionalized PEG derivatives which are covalently attached to solid supports, such as polystyrene.
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: August 10, 1993
    Assignee: University of Minnesota
    Inventors: George Barany, Fernando Albericio, Jane Chang, Samuel Zalipsky, Nuria A. Sole
  • Patent number: 5219564
    Abstract: Copolymers of poly(alkylene oxides) and amino acids or peptide sequences are disclosed, which amino acids or peptide sequences have pendant functional groups that are capable of being conjugated with pharmaceutically active compounds for drug delivery systems and cross-linked to form polymer matrices functional as hydrogel membranes. The copolymers can also be formed into conductive materials. Methods are also disclosed for preparing the polymers and forming the drug conjugates, hydrogel membranes and conductive materials.
    Type: Grant
    Filed: July 5, 1991
    Date of Patent: June 15, 1993
    Assignee: Enzon, Inc.
    Inventors: Samuel Zalipsky, Durgadas Bolikal, Aruna Nathan, Joachim B. Kohn