Abstract: A serum-stable mixture of lipids capable of encapsulating an active agent to form a liposome, said mixture comprising phosphatidylcholine and phosphatidylethanolamine in a ratio in the range of about 0.5 to about 8. The mixture may also include pH sensitive anionic and cationic amphiphiles, such that the mixture is amphoteric, being negatively charged or neutral at pH 7.4 and positively charged at pH 4. Amphoteric liposomes comprising such a mixture may be used for encapsulating nucleic acid therapeutics, such as oligonucleotides and DNA plasmids. The drug/lipid ratio may be adjusted to target the liposomes to particular organs or other sites in the body.

Abstract: The invention suggests amphoteric lipids wherein one or more amphoteric groups having an isoelectric point between 4 and 9 are substituted on a membranous or membrane-forming amphiphilic substance, as well as liposomes containing such compounds.

Abstract: A serum-stable mixture of lipids capable of encapsulating an active agent to form a liposome, said mixture comprising phosphatidylcholine and phosphatidylethanolamine in a ratio in the range of about 0.5 to about 8. The mixture may also include pH sensitive anionic and cationic amphiphiles, such that the mixture is amphoteric, being negatively charged or neutral at pH 7.4 and positively charged at pH 4. Amphoteric liposomes comprising such a mixture may be used for encapsulating nucleic acid therapeutics, such as oligonucleotides and DNA plasmids. The drug/lipid ratio may be adjusted to target the liposomes to particular organs or other sites in the body.

Abstract: A serum-stable mixture of lipids capable of encapsulating an active agent to form a liposome, said mixture comprising phosphatidylcholine and phosphatidylethanolamine in a ratio in the range of about 0.5 to about 8. The mixture may also include pH sensitive anionic and cationic amphiphiles, such that the mixture is amphoteric, being negatively charged or neutral at pH 7.4 and positively charged at pH 4. Amphoteric liposomes comprising such a mixture may be used for encapsulating nucleic acid therapeutics, such as oligonucleotides and DNA plasmids. The drug/lipid ratio may be adjusted to target the liposomes to particular organs or other sites in the body.

Abstract: The invention relates to compositions and methods to inhibit gene expression. In particular, the invention provides DNAi oligonucleotides sequestered by amphoteric liposomes for the treatment of cancer.

Abstract: The invention suggests amphoteric lipids wherein one or more amphoteric groups having an isoelectric point between 4 and 9 are substituted on a membranous or membrane-forming amphiphilic substance, as well as liposomes containing such compounds.

Abstract: A method for preparing amphoteric liposomes loaded with a polyanionic active agent as cargo, characterised by admixing an aqueous solution of said polyanionic active agent and an alcoholic solution of one or more amphiphiles and buffering said admixture to an acidic pH, said one or more amphiphiles being susceptible of forming amphoteric liposomes at said acidic pH, thereby to form such amphoteric liposomes in suspension encapsulating said active agent under conditions such that said liposomes form aggregates, and thereafter treating said suspension to dissociate said aggregates. Also disclosed are nucleic acid loaded amphoteric liposomes produced in accordance with the method, wherein said nucleic acids are oligonucleotides and said liposomes are multilamellar.

Abstract: The invention relates to compositions and methods to inhibit gene expression. In particular, the invention provides DNAi oligonucleotides sequestered by amphoteric liposomes for the treatment of cancer.

Abstract: The invention suggests amphoteric lipids wherein one or more amphoteric groups having an isoelectric point between 4 and 9 are substituted on a membranous or membrane-forming amphiphilic substance, as well as liposomes containing such compounds.

Abstract: The invention relates to compositions and methods to inhibit gene expression. In particular, the invention provides DNAi oligonucleotides sequestered by amphoteric liposomes for the treatment of cancer.

Abstract: The invention relates to amphoteric liposomal formulations which are provided with great serum stability and are suitable for the intracellular delivery of oligonucleotides.

Abstract: The invention suggests a pH-sensitive cationic lipid with a pKa value between 3.5 and 8, according to the general formula cation-spacer-Y-spacer-X-lipid, wherein Y and X represent linking groups. Furthermore, liposomes are described, which liposomes include said optionally cationic lipids.

Abstract: The invention suggests amphoteric lipids wherein one or more amphoteric groups having an isoelectric point between 4 and 9 are substituted on a membranous or membrane-forming amphiphilic substance, as well as liposomes containing such compounds.

Abstract: A method for preparing amphoteric liposomes loaded with polyanionic active agent as cargo, characterised by admixing an aqueous solution of said polyanionic active agent and an alcoholic solution of one or more amphiphiles and buffering said admixture to an acidic pH, said one or more amphiphiles being susceptible of forming amphoteric liposomes at said acidic pH, thereby to form such amphoteric liposomes in suspension encapsulating said active agent under conditions such that said liposomes form aggregates, and thereafter treating said suspension to dissociate said aggregates. Also disclosed are nucleic acid loaded amphoteric liposomes produced in accordance with the method, wherein said nucleic acids are oligonucleotides and said liposomes are multilamellar.

Abstract: Amphoteric liposomes are proposed, which comprise positive and negative membrane-based or membrane-forming charge carriers as well as the use of these liposomes.

Abstract: A serum-stable mixture of lipids capable of encapsulating an active agent to form a liposome, said mixture comprising phosphatidylcholine and phosphatidylethanolamine in a ratio in the range of about 0.5 to about 8. The mixture may also include pH sensitive anionic and cationic amphiphiles, such that the mixture is amphoteric, being negatively charged or neutral at pH 7.4 and positively charged at pH 4. Amphoteric liposomes comprising such a mixture may be used for encapsulating nucleic acid therapeutics, such as oligonucleotides and DNA plasmids. The drug/lipid ratio may be adjusted to target the liposomes to particular organs or other sites in the body.

Abstract: Amphoteric liposomes are proposed, which comprise positive and negative membrane-based or membrane-forming charge carriers as well as the use of these liposomes.

Abstract: Amphoteric liposomes are proposed, which comprise positive and negative membrane-based or membrane-forming charge carriers as well as the use of these liposomes.

Abstract: A method for the production of nano- or microcapsules having a diameter of from 20 nm to 40 ?m is suggested, wherein template particles are supplied in an aqueous medium, electrically recharged with a polyelectrolyte, re-recharged without separation or washing steps using a second polyelectrolyte having a complementary charge with respect to the first polyelectrolyte, and said process is optionally continued with alternately charged polyelectrolytes.

Abstract: The invention relates to compositions and methods to inhibit gene expression. In particular, the invention provides DNAi oligonucleotides sequestered by amphoteric liposomes for the treatment of cancer.