Patents Assigned to Shearwater Corporation
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Patent number: 6495659Abstract: The invention provides a sterically hindered polymer that comprises a water-soluble and non-peptidic polymer backbone having at least one terminus covalently bonded to an alkanoic acid or alkanoic acid derivative, wherein the carbon adjacent to the carbonyl group of the acid or acid derivative group has an alkyl or aryl group pendent thereto. The steric effects of the alkyl or aryl group allow greater control of the hydrolytic stability of polymer derivatives. The polymer backbone may be poly(ethylene glycol).Type: GrantFiled: December 20, 2000Date of Patent: December 17, 2002Assignee: Shearwater CorporationInventors: Michael David Bentley, Xuan Zhao, Xiaoming Shen, Lihong Guo
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Publication number: 20020182172Abstract: The present invention provides water-soluble polymer conjugates of triazine derivatives using water soluble and non-peptidic polymer backbones, such as poly(ethylene glycol). The invention includes conjugates made using mPEG, bifunctional PEG, branched or multi-arm PEG, and forked PEG. The invention further includes a method of forming such conjugates and a method of treating conditions responsive to triazine derivatives using the conjugates.Type: ApplicationFiled: November 30, 2001Publication date: December 5, 2002Applicant: Shearwater CorporationInventors: Michael David Bentley, Xuan Zhao, Robert Shorr
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Publication number: 20020156047Abstract: The invention provides multi-arm block copolymers useful as drug delivery vehicles comprising a central core molecule, such as a residue of a polyol, and at least three copolymer arms covalently attached to the central core molecule, each copolymer arm comprising an inner hydrophobic polymer segment covalently attached to the central core molecule and an outer hydrophilic polymer segment covalently attached to the hydrophobic polymer segment, wherein the central core molecule and the hydrophobic polymer segment define a hydrophobic core region. The solubility of hydrophobic biologically active agents can be improved by entrapment within the hydrophobic core region of the block copolymer. The invention further includes pharmaceutical compositions including such block copolymers, methods of making such copolymers and pharmaceutical compositions, and methods of using the block copolymers as drug delivery vehicles.Type: ApplicationFiled: January 22, 2002Publication date: October 24, 2002Applicant: Shearwater CorporationInventor: Xuan Zhao
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Patent number: 6461603Abstract: The present invention provides water-soluble polymer conjugates of the anti-malarial drug, artelinic acid, using water soluble and non-peptidic polymer backbones, such as poly(ethylene glycol). The invention includes conjugates made using mPEG, bifunctional PEG and multi-arm PEG. The invention further includes a method of forming such conjugates and a method of treating malaria using the conjugates.Type: GrantFiled: February 27, 2001Date of Patent: October 8, 2002Assignee: Shearwater CorporationInventors: Michael David Bentley, Xuan Zhao, Jeremy Lloyd Clark
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Patent number: 6461602Abstract: Poly(ethylene glycol) carbamate derivatives useful as water-soluble pro-drugs are disclosed. These degradable poly(ethylene glycol) carbamate derivatives also have potential applications in controlled hydrolytic degradation of hydrogels. In such degradable hydrogels, drugs may be either trapped in the gel and released by diffusion as the gel degrades, or they may be covalently bound through hydrolyzable carbamate linkages. Hydrolysis of these carbamate linkages releases the amine drug at a controllable rate as the gel degrades.Type: GrantFiled: April 26, 2001Date of Patent: October 8, 2002Assignee: Shearwater CorporationInventors: Michael David Bentley, Xuan Zhao
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Patent number: 6448369Abstract: This invention provides a method for preparing, in high purity and high yield, heterobifunctional derivatives of poly(ethylene glycol) or related polymers. A chromatographic purification step is not necessary in the method. In accordance with the method of the invention, an intermediate polymer having a formula of W-Poly-OH is provided bearing a removable group W at one terminus. The intermediate polymer W-Poly-OH is first altered by modifying the OH group to a first functional group X, followed by the removal of W to generate a second hydroxyl group. The latter hydroxyl group may then be further converted to a second functional group Y, thus providing the desired heterobifunctional derivative.Type: GrantFiled: November 5, 1998Date of Patent: September 10, 2002Assignee: Shearwater CorporationInventors: Michael David Bentley, J. Milton Harris, Antoni Kozlowski
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Patent number: 6437025Abstract: An activated, substantially water soluble poly(ethylene glycol) is provided having of a linear or branched poly(ethylene glycol) backbone and at least one terminus linked to the backbone through a hydrolytically stable linkage, wherein the terminus is branched and has proximal reactive groups. The free reactive groups are capable of reacting with active moieties in a biologically active agent such as a protein or peptide thus forming conjugates between the activated poly(ethylene glycol) and the biologically active agent.Type: GrantFiled: November 5, 2001Date of Patent: August 20, 2002Assignee: Shearwater CorporationInventors: J. Milton Harris, Antoni Kozlowski
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Patent number: 6436386Abstract: Isolatable, hydroxyapatite-targeting polymeric structures, and biologically active conjugates thereof, are provided. The polymeric structure includes a linear or branched water-soluble and non-peptidic polymer backbone, such as a PEG backbone, having at least two termini, a first terminus being covalently bonded to a hydroxyapatite-targeting moiety, such as a bisphosphonate, and a second terminus covalently bonded to a chemically reactive group, wherein said chemically reactive group is protected or unprotected. Methods of preparing and using hydroxyapatite-targeting polymeric structures, and biologically active conjugates thereof, are also provided.Type: GrantFiled: November 14, 2000Date of Patent: August 20, 2002Assignee: Shearwater CorporationInventors: Michael James Roberts, Antoni Kozlowski
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Publication number: 20020099133Abstract: The invention provides a method for preparing a 1-benzotriazolylcarbonate ester of a water-soluble and non-peptidic polymer by reacting a terminal hydroxyl group of a water-soluble and non-peptidic polymer with di(1-benzotriazolyl)carbonate in the presence of an amine base and an organic solvent. The polymer backbone can be poly(ethylene glycol). The 1-benzotriazolylcarbonate ester can then be reacted directly with a biologically active agent to form a biologically active polymer conjugate or reacted with an amino acid, such as lysine, to form an amino acid derivative.Type: ApplicationFiled: February 6, 2002Publication date: July 25, 2002Applicant: Shearwater CorporationInventor: Antoni Kozlowski
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Publication number: 20020086939Abstract: The invention provides a method for preparing a 1-benzotriazolylcarbonate ester of a water-soluble and non-peptidic polymer by reacting a terminal hydroxyl group of a water-soluble and non-peptidic polymer with di(1-benzotriazolyl)carbonate in the presence of an amine base and an organic solvent. The polymer backbone can be poly(ethylene glycol). The 1-benzotriazolylcarbonate ester can then be reacted directly with a biologically active agent to form a biologically active polymer conjugate or reacted with an amino acid, such as lysine, to form an amino acid derivative.Type: ApplicationFiled: February 6, 2002Publication date: July 4, 2002Applicant: Shearwater CorporationInventor: Antoni Kozlowski
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Patent number: 6413507Abstract: Poly(ethylene glycol) carbamate derivatives useful as water-soluble pro-drugs are disclosed. These degradable poly(ethylene glycol) carbamate derivatives also have potential applications in controlled hydrolytic degradation of hydrogels. In such degradable hydrogels, drugs may be either trapped in the gel and released by diffusion as the gel degrades, or they may be covalently bound through hydrolyzable carbamate linkages. Hydrolysis of these carbamate linkages releases the amine drug at a controllable rate as the gel degrades.Type: GrantFiled: December 23, 1999Date of Patent: July 2, 2002Assignee: Shearwater CorporationInventors: Michael David Bentley, Xuan Zhao
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Publication number: 20020082345Abstract: High molecular weight derivatives of activated poly(ethylene glycol) and the like polymers are prepared in high purity by conjugating a large PEG molecule to a small PEG molecule. Most of the reaction steps can be accomplished on the more readily purified small molecule to avoid laborious purification of the high molecular weight derivatives.Type: ApplicationFiled: December 18, 2001Publication date: June 27, 2002Applicant: Shearwater CorporationInventors: Antoni Kozlowski, Xiaoming Shen, Michael David Bentley, Zhihao Fang
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Publication number: 20020072573Abstract: This invention provides a method for preparing, in high purity and high yield, heterobifunctional derivatives of poly(ethylene glycol) or related polymers. A chromatographic purification step is not necessary in the method. In accordance with the method of the invention, an intermediate polymer having a formula of W-Poly-OH is provided bearing a removable group W at one terminus. The intermediate polymer W-Poly-OH is first altered by modifying the OH group to a first functional group X, followed by the removal of W to generate a second hydroxyl group. The latter hydroxyl group may then be further converted to a second functional group Y, thus providing the desired heterobifunctional derivative.Type: ApplicationFiled: February 8, 2002Publication date: June 13, 2002Applicant: Shearwater CorporationInventors: Michael David Bentley, J. Milton Harris, Antoni Kozlowski
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Publication number: 20020052430Abstract: An activated, substantially water soluble poly(ethylene glycol) is provided having of a linear or branched poly(ethylene glycol) backbone and at least one terminus linked to the backbone through a hydrolytically stable linkage, wherein the terminus is branched and has proximal reactive groups. The free reactive groups are capable of reacting with active moieties in a biologically active agent such as a protein or peptide thus forming conjugates between the activated poly(ethylene glycol) and the biologically active agent.Type: ApplicationFiled: November 5, 2001Publication date: May 2, 2002Applicant: Shearwater CorporationInventors: J. Milton Harris, Antoni Kozlowski
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Patent number: 6376604Abstract: The invention provides a method for preparing a 1-benzotriazolylcarbonate ester of a water-soluble and non-peptidic polymer by reacting a terminal hydroxyl group of a water-soluble and non-peptidic polymer with di(1-benzotriazolyl) carbonate in the presence of an amine base and an organic solvent. The polymer backbone can be poly(ethylene glycol). The 1-benzotriazolylcarbonate ester can then be reacted directly with a biologically active agent to form a biologically active polymer conjugate or reacted with an amino acid, such as lysine, to form an amino acid derivative.Type: GrantFiled: December 18, 2000Date of Patent: April 23, 2002Assignee: Shearwater CorporationInventor: Antoni Kozlowski
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Publication number: 20020040076Abstract: An activated, substantially water soluble poly(ethylene glycol) is provided having of a linear or branched poly(ethylene glycol) backbone and at least one terminus linked to the backbone through a hydrolytically stable linkage, wherein the terminus is branched and has proximal reactive groups. The free reactive groups are capable of reacting with active moieties in a biologically active agent such as a protein or peptide thus forming conjugates between the activated poly(ethylene glycol) and the biologically active agent.Type: ApplicationFiled: November 5, 2001Publication date: April 4, 2002Applicant: Shearwater CorporationInventors: J. Milton Harris, Antoni Kozlowski
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Publication number: 20020037949Abstract: An activated, substantially water soluble poly(ethylene glycol) is provided having of a linear or branched poly(ethylene glycol) backbone and at least one terminus linked to the backbone through a hydrolytically stable linkage, wherein the terminus is branched and has proximal reactive groups. The free reactive groups are capable of reacting with active moieties in a biologically active agent such as a protein or peptide thus forming conjugates between the activated poly(ethylene glycol) and the biologically active agent.Type: ApplicationFiled: November 5, 2001Publication date: March 28, 2002Applicant: Shearwater CorporationInventors: J. Milton Harris, Antoni Kozlowski
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Patent number: 6362254Abstract: An activated, substantially water soluble poly(ethylene glycol) is provided having of a linear or branched poly(ethylene glycol) backbone and at least one terminus linked to the backbone through a hydrolytically stable linkage, wherein the terminus is branched and has proximal reactive groups. The free reactive groups are capable of reacting with active moieties in a biologically active agent such as a protein or peptide thus forming conjugates between the activated poly(ethylene glycol) and the biologically active agent.Type: GrantFiled: March 11, 1999Date of Patent: March 26, 2002Assignee: Shearwater CorporationInventors: J. Milton Harris, Antoni Kozlowski
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Patent number: 6348558Abstract: A water soluble polymer is provided having two or more oligomers linked to each other by hydrolytically degradable carbonate linkages. The polymer can be hydrolytically degraded into oligomers (e.g., oligomers of ethylene oxide) under physiological conditions. The polymer can be conjugated to biologically active agents such as proteins or peptides to impart improved water solubility, reduced immunogenicity, reduced rate of renal clearance, and increased stability. The polymer is useful in making hydrolytically degradable hydrogels which can be used in drug delivery and related biomedical applications. One example of the polymer is a poly(ether carbonate) of the formula X—O—[(—CH2CH2—O—)n—CO2—]n—(CH2CH2))n-y where X and Y are independently H, alkyl, alkenyl, aryl, or a reactive moiety, and at least one of X and Y is a reactive moiety.Type: GrantFiled: December 10, 1999Date of Patent: February 19, 2002Assignee: Shearwater CorporationInventors: J. Milton Harris, Michael David Bentley, Xuan Zhoa, Xiaoming Shen
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Publication number: 20020013266Abstract: A substantially hydrophilic conjugate is provided having a peptide that is capable of passing the blood-brain barrier covalently linked to a water-soluble nonpeptidic polymer such as polyethylene glycol. The conjugate exhibits improved solubility and in vivo stability and is capable of passing the blood-brain barrier of an animal.Type: ApplicationFiled: September 19, 2001Publication date: January 31, 2002Applicant: Shearwater CorporationInventors: Michael David Bentley, Michael James Roberts