Abstract: A heterobifunctional poly(ethylene glycol) is provided having a hydrolytically degradable linkage, a first terminus comprising an acrylate group, and a second terminus comprising a target such as a protein or pharmaceutical agent or a reactive moiety capable of coupling to a target. Hydrogels can be prepared. The hydrogels can be used as a carrier for a protein or a pharmaceutical agent that can be readily released in a controlled fashion.

Abstract: 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 (polyethylene glycol) and the biologically active agent.

Abstract: Polymeric reagents are provided comprising a moiety of atoms arranged in a specific order, wherein the moiety is positioned between a water-soluble polymer and a reactive group. The polymeric reagents are useful for, among other things, forming polymer-active agent conjugates. Related methods, compositions, preparations, and so forth are also provided.

Abstract: The present invention provides a water soluble, nonpeptidic polymer comprising two or more alkylene oxide-based oligomers linked together by hydrolytically degradable linkages such as carbonates. Typically, the oligomer portion of the polymer is an amphiphilic triblock copolymer having a central propylene oxide block or butylene oxide block positioned between two ethylene oxide blocks. The polymer can be hydrolytically degraded into oligomers under physiological conditions. In aqueous media, the polymer preferably forms thermally reversible, hydrolytically degradable hydrogels that can be used, for example, for drug delivery and related biomedical applications.

Abstract: 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. On example of the polymer is a poly (ether carbonate) of the formula X—O—[(—CH2CH2-0-)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.

Abstract: 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.

Abstract: Methods for preparing water soluble, non-peptidic polymers carrying carboxyl functional groups, particularly carboxylic acid functionalized poly(ethylene glycol) (PEG) polymers, are disclosed, as are the products of these methods. In general, an ester reagent R(C?O)OR?, where R? is a tertiary group and R comprises a functional group X, is reacted with a water soluble, non-peptidic polymer POLY-Y, where Y is a functional group which reacts with X to form a covalent bond, to form a tertiary ester of the polymer, which is then treated with a strong base in aqueous solution, to form a carboxylate salt of the polymer. Typically, this carboxylate salt is then treated with an inorganic acid in aqueous solution, to convert the carboxylate salt to a carboxylic acid, thereby forming a carboxylic acid functionalized polymer.

Abstract: A poly(ethylene glycol) derivative is disclosed that is activated with a sulfone moiety for selective attachment to thiol moieties on molecules and surfaces. The activated PEG is water soluble, hydrolytically stable for extended periods, and forms hydrolytically stable linkages with thiol moieties. The linkages generally are not reversible in reducing environments. The PEG derivative is useful for modifying the characteristics of substances including modifying biologically active molecules and surfaces for biocompatibility. Methods for synthesizing the active PEG and for preparing conjugates of the active PEG and other substances, including biologically active substances, are also disclosed.

Abstract: 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.

Abstract: PEG and related polymer derivatives having weak, hydrolytically unstable linkages near the reactive end of the polymer are provided for conjugation to drugs, including proteins, enzymes, small molecules, and others. These derivatives provide a sufficient circulation period for a drug-PEG conjugate, followed by hydrolytic breakdown of the conjugate and release of the bound molecule. In some cases, drugs that demonstrate reduced activity when permanently coupled to PEG maintain a therapeutically suitable activity when coupled to a degradable PEG in accordance with the invention. The PEG derivatives of the invention can be used to impart improved water solubility, increased size, a slower rate of kidney clearance, and reduced immunogenicity to a conjugate formed by attachment thereto. Controlled hydrolytic release of the bound molecule into an aqueous environment can then enhance the drug's delivery profile by providing a delivery system which employs such polymers and utilizes the teachings provided herein.

Abstract: PEG and related polymer derivatives having weak, hydrolytically unstable linkages near the reactive end of the polymer are provided for conjugation to drugs, including proteins, enzymes, small molecules, and others. These derivatives provide a sufficient circulation period for a drug-PEG conjugate and then for hydrolytic breakdown of the conjugate and release of the bound molecule. In some cases, drugs that previously had reduced activity when permanently coupled to PEG can have therapeutically suitable activity when coupled to a degradable PEG in accordance with the invention. The PEG of the invention can be used to impart water solubility, size, slow rate of kidney clearance, and reduced immunogenicity to the conjugate. Controlled hydrolytic release of the bound molecule in the aqueous environment can then enhance the drug delivery system.

Abstract: The present invention provides active, hydrophilic polymer-modified derivatives of insulin. The insulin derivatives of the invention are, in one aspect, suitable for delivery to the lung and exhibit pharmakokinetic and/or pharmacodynamic properties that are significantly improved over native insulin.

Abstract: Multi-armed, monofunctional, and hydrolytically stable polymers are described having the structure wherein Z is a moiety that can be activated for attachment to biologically active molecules such as proteins and wherein P and Q represent linkage fragments that join polymer arms polya and polyb, respectively, to central carbon atom, C, by hydrolytically stable linkages in the absence of aromatic rings in the linkage fragments. R typically is hydrogen or methyl, but can be a linkage fragment that includes another polymer arm. A specific example is an mPEG disubstituted lysine having the structure where mPEGa and mPEGb have the structure CH3O—(CH2CH2O)nCH2CH2— wherein n may be the same or different for polya- and polyb- and can be from 1 to about 1,150 to provide molecular weights of from about 100 to 100,000.

Abstract: The present invention provides, among other things, methods for preparing functionalized and other polymers from polymer from polymer alcohols such as poly(ethylene glycol)s. In addition, polymer compositions, conjugates, polymeric reagents, are also provided.

Abstract: Polymeric reagents are provided comprising a moiety of atoms arranged in a specific order, wherein the moiety is positioned between a water-soluble polymer and a reactive group. The polymeric reagents are useful for, among other things, forming polymer-active agent conjugates. Related methods, compositions, preparations, and so forth are also provided.