Abstract: PEG-chitosan conjugates comprising chitosan and polyethylene glycol moieties or derivatives thereof which are bonded together and their use in medicine is described. In one embodiment, the conjugate comprises a chitosan moiety or a derivative thereof and a polyethylene glycol moiety or a derivative thereof which are bonded together via the amino function on the chitosan by the use of an activated chitosan species. In another embodiment, the conjugate comprises a chitosan moiety or a derivative thereof and a polyethylene glycol moiety or a derivative thereof which are bonded together, the chitosan portion of the conjugate having a molecular weight in the range of from 10 kilodaltons to 1000 kilodaltons.

Abstract: PEG-chitosan conjugates comprising chitosan and polyethylene glycol moieties or derivatives thereof which are bonded together and their use in medicine is described. In one embodiment, the conjugate comprises a chitosan moiety or a derivative thereof and a polyethylene glycol moiety or a derivative thereof which are bonded together via the amino function on the chitosan by the use of an activated chitosan species. In another embodiment, the conjugate comprises a chitosan moiety or a derivative thereof and a polyethylene glycol moiety or a derivative thereof which are bonded together, the chitosan portion of the conjugate having a molecular weight in the range of from 10 kilodaltons to 1000 kilodaltons.

Abstract: A process for attaching a polyethylene glycol compound to a macromolecule to prepare a conjugate or adduct between the polyethylene glycol compound and the macromolecule is described. The process comprises the steps of (1) preparing an activated PEG or an activated PEG derivative by incorporating an acrylic ester, an acrylic thioester or an acrylamido group into the PEG or PEG derivative; (2) reacting the activated PEG or PEG derivative with a macromolecular material comprising one or more sulphydryl groups, primary amino groups and/or secondary amino groups and (3) recovering the conjugate of the PEG or PEG derivative and the macromolecular material.

Abstract: Lamellar particles are provided comprising a biodegradable and biocompatible polymer and carrying a cationic charge on their surface. These particles are prepared by mixing a preformed negatively charged lamellar particle with a positively charged material. Compositions using these particles may include genetic material or antigens, for example, and may be used as a drug delivery system, such as a sustained release system.

Abstract: PEG-chitosan conjugates comprising chitosan and polyethylene glycol moieties or derivatives thereof which are bonded together and their use in medicine is described. In one embodiment, the conjugate comprises a chitosan moiety or a derivative thereof and a polyethylene glycol moiety or a derivative thereof which are bonded together via the amino function on the chitosan by the use of an activated chitosan species. In another embodiment, the conjugate comprises a chitosan moiety or a derivative thereof and a polyethylene glycol moiety or a derivative thereof which are bonded together, the chitosan portion of the conjugate having a molecular weight in the range of from 10 kilodaltons to 1000 kilodaltons.

Abstract: A composition for delivering a biologically active polyanionic molecule comprising a linear polymer with a backbone comprising amido and tertiary amino groups arranged regularly on the backbone and biologically active polyanionic molecule bound to the polymer. Preferably, the linear polymer comprises a poly(amidoamine). Preferably, the biologically active polyanionic molecule is a nucleic acid, more preferably a DNA. The compositions are useful for delivering nucleic acids to a cell in a cell transformation, transfection or gene therapy method.

Abstract: Lamellar particles are provided comprising a biodegradable and biocompatible polymer and carrying a cationic charge on their surface. These particles are prepared by mixing a preformed negatively charged lamellar particle with a positively charged material. Compositions using these particles may include genetic material or antigens, for example, and may be used as a drug delivery system, such as a sustained release system.

Abstract: There is provided a composition for the nasal delivery of a cannabinoid which comprises a cannabinoid in a biphasic delivery system or a cannabinoid in a microsphere delivery system.

Abstract: A composition is provided including: (a) a nucleic acid or an oligonucleotide; and (b) a block copolymer containing a hydrophilic block that carries functional groups that provide the block with a positive charge. These compositions may be used to deliver a nucleic acid or an oligonucleotide to a cell.

Abstract: The present invention provides a composition comprising an oil-in-water emulsion and a drug dissolved in the emulsion. The oil phase comprises a hydroxylated oil, particularly a hydroxylated vegetable oil. The preferred hydroxylated vegetable oil is castor oil.

Abstract: The invention provides a composition for delivery of an active agent comprising a plurality of lamellar particles of a biodegradable polymer which is at least in part crystalline, and an active agent adsorbed to at least most of the particles. Preferably the biodegradablepolymer is at least 5% by weight crystalline. Preferred biodegradable polymers are poly(L-lactide) (L.PLA) or copolymers or blends of L.PLA. The particles are especially useful for the immobilization of antigens or allergens for vaccines.

Abstract: The invention relates to microspheres which are suitable for biomedical uses which have a diameter in the range of 10 nm to 2 mm and which comprise a substantially spherical core particle of a non-water-soluble polymer and an outer surface layer consisting substantially of a water-soluble polymer. The water-soluble polymer is conjugated to polyethylene glycol and the non-water-soluble core particle is attached to the water-soluble polymer by the polyethylene glycol moiety. The microspheres are prepared by dissolving the non-water-soluble polymer in a suitable first solvent, dispersing the polymer solution in a solution of the PEG/water-soluble polymer conjugate and evaporating the first solvent to form microspheres in which the PEG anchors the water-soluble polymer to the core particle.

Abstract: Provided are biodegradable microparticles, which exhibit a linear release profile of active agent, and methods for making the microparticles. The microparticles include a mixture of a biodegradable polymer, a water soluble polymer, and an active agent. Preferred biodegradable polymers include lactide homopolymers or copolymers of lactide and glycolide, and preferred water soluble polymers include poly(ethylene glycol) (PEG) or PEG copolymers. The microparticles are made using an emulsion/solvent extraction method, in which the continuous phase of the secondary emulsion contains an organic solvent that is miscible with the organic solvent in the primary emulsion.