Patents by Inventor Ai-Zhi Piao

Ai-Zhi Piao 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: 9155722
    Abstract: Biodegradable and bioabsorbable block copolymers, which can be in the form of solid powder or powder wax compositions that can be easily reconstituted into an aqueous polymer solution and exhibit reverse thermal gellation properties upon exposure to elevated temperatures, are provided. Methods of making using these copolymers are also provided.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: October 13, 2015
    Assignee: PROTHERICS SALT LAKE CITY, INC.
    Inventors: Kirk D. Fowers, Ramesh C. Rathi, Ai-Zhi Piao
  • Patent number: 8753621
    Abstract: Improved biodegradable and bioabsorbable BAB-block copolymers exhibiting reverse thermal gellation properties, and aqueous polymer compositions including the BAB-block copolymers, are provided. Methods of making the improved BAB-block copolymers and compositions including the same are also provided.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: June 17, 2014
    Assignee: Protherics Salt Lake City, Inc.
    Inventors: Kirk D. Fowers, Ramesh C. Rathi, Ai-Zhi Piao
  • Publication number: 20110070188
    Abstract: Improved biodegradable and bioabsorbable BAB-block copolymers exhibiting reverse thermal gellation properties, and aqueous polymer compositions including the BAB-block copolymers, are provided. Methods of making the improved BAB-block copolymers and compositions including the same are also provided.
    Type: Application
    Filed: September 20, 2010
    Publication date: March 24, 2011
    Applicant: Protherics Salt Lake City, Inc.
    Inventors: Kirk D. FOWERS, Ramesh C. RATHI, Ai-Zhi PIAO
  • Publication number: 20110071216
    Abstract: Biodegradable and bioabsorbable block copolymers, which can be in the form of solid powder or powder wax compositions that can be easily reconstituted into an aqueous polymer solution and exhibit reverse thermal gellation properties upon exposure to elevated temperatures, are provided. Methods of making using these copolymers are also provided.
    Type: Application
    Filed: September 20, 2010
    Publication date: March 24, 2011
    Applicant: Protherics Salt Lake City, Inc.
    Inventors: Kirk D. FOWERS, Ramesh C. RATHI, Ai-Zhi PIAO
  • Patent number: 7135190
    Abstract: A water soluble, biodegradable reverse thermal gelation system comprising a mixture of at least two types of tri-block copolymer components is disclosed. The tri-block copolymer components are made of a hydrophobic biodegradable polyester A-polymer block and a hydrophilic polyethylene glycol B-polymer block. The drug release and gel matrix erosion rates of the biodegradable reverse thermal gelation system may be modulated by various parameters such as the hydrophobic/hydrophilic component contents, polymer block concentrations, molecular weights and gelation temperatures, and weight ratios of the tri-block copolymer components in the mixture.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: November 14, 2006
    Assignee: Macromed, Inc.
    Inventors: Ai-Zhi Piao, Chung Shih
  • Patent number: 7018645
    Abstract: A water soluble, biodegradable reverse thermal gelation system comprising a mixture of at least two types of tri-block copolymer components is disclosed. The tri-block copolymer components are made of a hydrophobic biodegradable polyester A-polymer block and a hydrophilic polyethylene glycol B-polymer block. The drug release and gel matrix erosion rates of the biodegradable reverse thermal gelation system may be modulated by various parameters such as the hydrophobic/hydrophilic component contents, polymer block concentrations, molecular weights and gelation temperatures, and weight ratios of the tri-block copolymer components in the mixture.
    Type: Grant
    Filed: April 27, 2000
    Date of Patent: March 28, 2006
    Assignee: Macromed, Inc.
    Inventors: Ai-Zhi Piao, Chung Shih
  • Publication number: 20060034889
    Abstract: A water soluble, biodegradable AB type diblock copolymer which comprises 61 to 85% by weight of a biodegradable, hydrophobic A block comprising a biodegradable polyester, and 15 to 39% by weight of a biocompatible, hydrophilic B block comprising a monofunctional polyethylene glycol(PEG) having a number average molecular weight less than 5000, and wherein said diblock copolymer has a number average molecular weight less than 15000 and possesses reverse thermal gelation properties.
    Type: Application
    Filed: August 16, 2004
    Publication date: February 16, 2006
    Inventors: Seongbong Jo, Ai-Zhi Piao
  • Patent number: 6998137
    Abstract: The present invention relates to compositions and methods for the modulated release of one or more proteins or peptides. The composition is comprised of a biocompatible polymeric matrix, a protein and/or peptide, and a sparingly water-soluble or essentially insoluble particle. The protein is deposited by adsorption or some other mechanism onto the sparingly water-soluble biocompatible particle wherein the protein-particle combination is dispersed within the polymeric matrix. The deposition of the protein onto the particle acts to modulate the release of the protein or peptide from dosage forms including long-acting dosage systems.
    Type: Grant
    Filed: April 5, 2001
    Date of Patent: February 14, 2006
    Assignee: MacroMed, Inc.
    Inventors: Chung Shih, Gaylen Zentner, Ai-Zhi Piao
  • Publication number: 20040185104
    Abstract: A water soluble, biodegradable reverse thermal gelation system comprising a mixture of at least two types of tri-block copolymer components is disclosed. The tri-block copolymer components are made of a hydrophobic biodegradable polyester A-polymer block and a hydrophilic polyethylene glycol B-polymer block. The drug release and gel matrix erosion rates of the biodegradable reverse thermal gelation system may be modulated by various parameters such as the hydrophobic/hydrophilic component contents, polymer block concentrations, molecular weights and gelation temperatures, and weight ratios of the tri-block copolymer components in the mixture.
    Type: Application
    Filed: January 29, 2004
    Publication date: September 23, 2004
    Applicant: MacroMed, Inc.
    Inventors: Ai-Zhi Piao, Chung Shih
  • Publication number: 20040185101
    Abstract: Biodegradable ABA-type or BAB-type triblock copolymers are disclosed that, at functional concentrations, are capable of solubilizing drugs, especially hydrophobic drugs, in a hydrophilic environment to form a solution at temperatures relevant for parenteral and particularly for intravenous administration as well as all other routes of administration benefiting from an aqueous drug solution. The copolymers are comprised of about 50.1 to 65% by weight of biodegradable hydrophobic A polymer block(s) comprising a biodegradable polyester, and about 35 to 49.9% by weight of a biodegradable hydrophilic B polymer block comprising a polyethylene glycol (PEG), and wherein the triblock copolymer has a weight-averaged molecular weight of between about 1500 to 3099 Daltons.
    Type: Application
    Filed: December 11, 2003
    Publication date: September 23, 2004
    Applicant: MacroMed, Incorporated.
    Inventors: Chung Shih, Gaylen Zentner, Ai-zhi Piao, Kirk Dee Fowers
  • Publication number: 20030228366
    Abstract: A composition having enhanced reconstitution properties and method of use is disclosed. The composition comprises one or more biodegradable block copolymer drug carriers; and a reconstitution enhancing and enabling agent comprising polyethylene glycol (PEG), a PEG derivative or a mixture of PEG and a PEG derivative; and wherein the biodegradable block copolymer drug carrier is soluble in an aqueous solution and in the liquid reconstitution enhancing and enabling agent.
    Type: Application
    Filed: June 11, 2002
    Publication date: December 11, 2003
    Inventors: Chung Shih, Gaylen M. Zentner, Ai-Zhi Piao
  • Patent number: 6592899
    Abstract: Polymeric compositions having improved capability of solubilizing a drug in a hydrophilic environment to form a solution, comprising: a biodegradable polyester oligomer; and biodegradable AB-type, ABA-type, or BAB-type block copolymers are disclosed. The copolymers are comprised of about 50.1 to 65% by weight of a biodegradable, hydrophobic A polymer block comprising a biodegradable polyester, and about 35 to 49.9% by weight of a hydrophilic B polymer block comprising a polyethylene glycol (PEG), and wherein the block copolymer has a weight averaged molecular weight of between 2400 to 4999. The biodegradable polyester oligomer of said composition is within a range of 0.01% to 30% by weight of the total polymer mixture, and the content of the biodegradable AB-type, ABA-type, or BAB-type block copolymer is within a range of 70% to 99.99% by weight of the total polymer mixture.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: July 15, 2003
    Assignee: Macromed Incorporated
    Inventors: Kirk Dee Fowers, Gaylen M. Zentner, Chung Shih, Ai-Zhi Piao
  • Publication number: 20030068377
    Abstract: Polymeric compositions having improved capability of solubilizing a drug in a hydrophilic environment to form a solution, comprising: a biodegradable polyester oligomer; and biodegradable AB-type, ABA-type, or BAB-type block copolymers are disclosed. The copolymers are comprised of about 50.1 to 65% by weight of a biodegradable, hydrophobic A polymer block comprising a biodegradable polyester, and about 35 to 49.9% by weight of a hydrophilic B polymer block comprising a polyethylene glycol (PEG), and wherein the block copolymer has a weight averaged molecular weight of between 2400 to 4999. The biodegradable polyester oligomer of said composition is within a range of 0.01% to 30% by weight of the total polymer mixture, and the content of the biodegradable AB-type, ABA-type, or BAB-type block copolymer is within a range of 70% to 99.99% by weight of the total polymer mixture.
    Type: Application
    Filed: October 3, 2001
    Publication date: April 10, 2003
    Applicant: Macromed, Incorporated
    Inventors: Kirk Dee Fowers, Gaylen M. Zentner, Chung Shih, Ai-Zhi Piao
  • Publication number: 20020192286
    Abstract: Biodegradable ABA-type or BAB-type triblock copolymers are disclosed that, at functional concentrations, are capable of solubilizing drugs, especially hydrophobic drugs, in a hydrophilic environment to form a solution at relevant temperatures for parenteral and particularly intravenous administration (temperatures of between at least 35 and 42° C.) as well as all other routes of administration benefiting from an aqueous drug solution. The copolymers are comprised of about 50.1 to 65% by weight of biodegradable hydrophobic A polymer block(s) comprising a biodegradable polyester, and about 35 to 49.9% by weight of a biodegradable hydrophilic B polymer block comprising a polyethylene glycol (PEG), and wherein the triblock copolymer has a weight-averaged molecular weight of between about 2400 to 4999.
    Type: Application
    Filed: October 3, 2001
    Publication date: December 19, 2002
    Applicant: Macromed, Incorporated
    Inventors: Chung Shih, Gaylen Zentner, Ai-zhi Piao, Kirk Dee Fowers
  • Publication number: 20020015737
    Abstract: The present invention relates to compositions and methods for the modulated release of one or more proteins or peptides. The composition is comprised of a biocompatible polymeric matrix, a protein and/or peptide, and a sparingly water-soluble or essentially insoluble particle. The protein is deposited by adsorption or some other mechanism onto the sparingly water-soluble biocompatible particle wherein the protein-particle combination is dispersed within the polymeric matrix. The deposition of the protein onto the particle acts to modulate the release of the protein or peptide from dosage forms including long-acting dosage systems.
    Type: Application
    Filed: April 5, 2001
    Publication date: February 7, 2002
    Applicant: MacroMed, Incorporated
    Inventors: Chung Shih, Gaylen Zentner, Ai-Zhi Piao