Patents Assigned to QLT PhotoTherapeutics, Inc.
  • Patent number: 6107325
    Abstract: Green porphyrins act as antigen-specific immunomodulators in the active phase of an immune response to a particular antigen. This effect occurs at ambient light levels.
    Type: Grant
    Filed: May 18, 1998
    Date of Patent: August 22, 2000
    Assignees: QLT PhotoTherapeutics, Inc., The University of British Columbia
    Inventors: Agnes H. Chan, David W. C. Hunt, Julia G. Levy, Modestus O. K. Obochi, Anna M. Richter, Guillermo O. Simkin
  • Patent number: 6096776
    Abstract: Green porphyrins act as antigen-specific immunomodulators in the active phase of an immune response to a particular antigen, as well as to interfere with intercellular communication. These effects occur in the absence of radiation absorbed by the green porphyrin.
    Type: Grant
    Filed: October 1, 1998
    Date of Patent: August 1, 2000
    Assignees: QLT PhotoTherapeutics, Inc., The University of British Columbia
    Inventors: Agnes H. Chan, David W. C. Hunt, Julia G. Levy, Modestus O. K. Obochi, Anna M. Richter, Guillermo O. Simkin
  • Patent number: 6086558
    Abstract: The present invention provides improved balloon catheter apparatuses for use in therapies requiring delivery of uniform light to a treatment area. The improved apparatus comprises a balloon having a defined treatment window where the window is delineated using a reflective material. The apparatus may further comprise a fiber optic cable that terminates in a diffusion tip where the diffusion tip is longer than the treatment window. The present invention further provides improved therapeutic methods that use the improved balloon catheters of the present invention.
    Type: Grant
    Filed: December 29, 1998
    Date of Patent: July 11, 2000
    Assignee: QLT PhotoTherapeutics, Inc.
    Inventors: Robert David Bower, Michael David Leslie Stonefield, Joseph Yan
  • Patent number: 6074666
    Abstract: Liposomal pharmaceutical formulations incorporating porphyrin photosensitizers useful for photodynamic therapy or diagnosis of malignant cells. The liposomal formulations comprise a porphyrin photosensitizer, particularly the hydro-mono benzoporphyrins (BPD) having light absorption maxima in the range of 670-780 nanometers, a disaccharide or polysaccharide and one or more phospholipids.
    Type: Grant
    Filed: June 13, 1995
    Date of Patent: June 13, 2000
    Assignee: QLT Phototherapeutics, Inc.
    Inventors: Narendra Raghunathji Desai, Bushra J. Agha, Kalidas Madhavrao Kale
  • Patent number: 6043237
    Abstract: Photodynamic therapy to prevent secondary cataracts is effected using photosensitizers such as green porphyrins as photoactive agents to destroy remnant lens epithelial cells.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: March 28, 2000
    Assignees: QLT PhotoTherapeutics, Inc., The University of the British of Columbia, Ciba Vision Opthalmics
    Inventors: Howard E. Meadows, Danielle Wenkstern, David R. Mallek, Marcello Nick Bussanich, Anna M. Richter, Julia G. Levy, Claude A. A. Hariton, Gustav Huber, Jack Rootman
  • Patent number: 6008241
    Abstract: Green porphyrins act as antigen-specific immunomodulators in the active phase of an immune response to a particular antigen. This effect occurs at ambient light levels.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: December 28, 1999
    Assignee: QLT PhotoTherapeutics, Inc.
    Inventors: Agnes H. Chan, David W. C. Hunt, Julia G. Levy, Modestus O. K. Obochi, Anna M. Richter, Guillermo O. Simkin
  • Patent number: 5945439
    Abstract: This invention is a process for the use of a combination of ionizing radiation in conjunction with certain benzoporphyrin derivative compounds (BPD), preferably the compound benzoporphyrin derivative-monoacid ring-A (BPD-MA), to mediate the destruction of diseased or unwanted cells or tissues. Specifically, the invention is a method in which the sensitizer compounds are administered either systemically or locally to the diseased or unwanted tissue and irradiated with ionizing radiation (such as might be produced by a .sup.60 Co or x-ray source). The treatment with benzoporphyrin derivative compounds appears to sensitize the target cells or tissues in that those cells do not readily recover from irradiation exposure. In addition, the process may be used to lower the effective amount of radiation applied to a particular tissue target.
    Type: Grant
    Filed: July 2, 1997
    Date of Patent: August 31, 1999
    Assignee: QLT PhotoTherapeutics, Inc.
    Inventors: Anna Richter, Julia G. Levy, David Dolphin
  • Patent number: 5910510
    Abstract: Photodynamic therapy of conditions of the eye, especially those conditions characterized by unwanted neovasculature, such as age-related macular degeneration, results in enhanced visual acuity for treated subjects.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: June 8, 1999
    Assignee: QLT Phototherapeutics Inc
    Inventors: H. Andrew Strong, Julia Levy, Gustav Huber, Mario Fsadni
  • Patent number: 5882328
    Abstract: Donor tissue containing antigen-presenting cells (APCs) can be modified to reduce rejection when the donor tissue is used as an allograft by exposing the donor tissue which has been treated with a photosensitizing agent having an absorption maximum between 400-900 nm to a wavelength absorbed by the photosensitizing agent so as to attenuate the APCs in the donor tissue but wherein the light is not cytotoxic to the APCs.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: March 16, 1999
    Assignee: QLT Phototherapeutics, Inc.
    Inventors: Julia G. Levy, Modestus O. K. Obochi
  • Patent number: 5883246
    Abstract: A compound of Formula I: ##STR1## wherein: Q represents identical alkyl groups, cycloalkyl groups having from 5 to 7 ring atoms, or aryl or heteroaryl groups having from 5 to 12 ring atoms andR represents identical hydrogen, alkyl, alcohol or carbonyl-containing groups;or a composition containing from 5 to 100 mole % by weight of the compound of Formula I. A novel method for synthesizing the compound of Formula I comprises the steps of: (a) reacting a compound of the formula:Q--CHO or Q--CH(OS)(OS')wherein Q is as defined above andS and S' are independently lower alkyl, an aryl group containing from 5 to 14 ring atoms, and --(CH.sub.2).sub.n -- where n=2-4, with an excess amount of a pyrrole in the presence of a catalytic amount of a strong Lewis or Bronsted acid;(b) removing any unreacted pyrrole or other solvents used by evaporation;(c) removing polymeric materials and removing the corresponding dipyrromethane by-product, leaving the compound of Formula I.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: March 16, 1999
    Assignee: QLT PhotoTherapeutics, Inc.
    Inventors: Christian Bruckner, Ross W. Boyle, David Dolphin
  • Patent number: 5834503
    Abstract: A method to prevent or inhibit the development of arterial plaque, comprising the steps of:a. administering to a subject an amount of a green porphyrin compound effective to prevent or inhibit said development; andb. allowing the inhibition to occur in the absence of irradiation with light absorbed by the green porphyrin,or a pharmaceutical composition for preventing or inhibiting the development of arterial plaque. The composition comprises:a. an amount of a green porphyrin compound effective to prevent or inhibit the development when administered to a subject in need of such treatment, even in the absence of irradiation with light absorbed by said the green porphyrin; andb. a pharmaceutically acceptable excipient.The administration of the green porphyrin need not be accompanied by any purposeful irradiation with light.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: November 10, 1998
    Assignee: QLT Phototherapeutics, Inc.
    Inventors: Barbara Kelly, Julia Levy, Philippe Maria Clotaire Margaron
  • Patent number: 5808054
    Abstract: A compound of Formula I: ##STR1## wherein: Q represents identical alkyl groups, cycloalkyl groups having from 5 to 7 ring atoms, or aryl or heteroaryl groups having from 5 to 12 ring atoms andR represents identical hydrogen, alkyl, alcohol or carbonyl-containing groups;or a composition containing from 5 to 100 mole % by weight of the compound of Formula I. A novel method for synthesizing the compound of Formula I comprises the steps of:(a) reacting a compound of the formula:Q--CHO or Q--CH(OS)(OS')wherein Q is as defined above and S and S' are independently lower alkyl, an aryl group containing from 5 to 14 ring atoms, and --(CH.sub.2).sub.n -- where n=2-4, with an excess amount of a pyrrole in the presence of a catalytic amount of a strong Lewis or Bronsted acid;(b) removing any unreacted pyrrole or other solvents used by evaporation;(c) removing polymeric materials and removing the corresponding dipyrromethane by-product, leaving the compound of Formula I.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: September 15, 1998
    Assignee: QLT PhotoTherapeutics, Inc.
    Inventors: Christian Bruckner, Ross W. Boyle, David Dolphin
  • Patent number: 5756541
    Abstract: Photodynamic therapy of conditions of the eye, especially those conditions characterized by unwanted neovasculature, such as age-related macular degeneration, results in enhanced visual acuity for treated subjects,
    Type: Grant
    Filed: March 11, 1996
    Date of Patent: May 26, 1998
    Assignee: QLT Phototherapeutics Inc
    Inventors: H. Andrew Strong, Julia Levy, Gustav Huber, Mario Fsadni
  • Patent number: 5707608
    Abstract: Liposomal compositions containing green porphyrins as photosensitizers are improved by enhancing the ratio of phospholipid to photosensitizer and by conducting the hydration an sizing of the liposomes in the composition at low temperature.
    Type: Grant
    Filed: August 2, 1995
    Date of Patent: January 13, 1998
    Assignee: QLT PhotoTherapeutics, Inc.
    Inventor: Ron Liu