This invention provides for a compound of formula (I), or a pharmaceutically acceptable salt thereof, wherein R.sup.A, R.sup.B, R.sub.2 and R.sub.4 are defined herein. The compounds of formula (I) and pharmaceutically acceptable salts thereof are cationic lipids useful in the delivery of biologically active agents to cells and tissues.

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A lipid membrane structure encapsulating an siRNA inside thereof and containing a lipid compound of the formula (I) as a lipid component (R.sup.1 and R.sup.2 represent CH.sub.3—(CH.sub.2).sub.n—CH═CH—CH.sub.2—CH═CH—(CH.sub.2).sub.m—, n represents an integer of 3 to 5, m represents an integer of 6 to 10, p represents an integer of 2 to 7, and R.sup.3 and R.sup.4 represent a C.sub.1-4 alkyl group or a C.sub.2-4 alkenyl group.

The present invention provides, in part, a biodegradable compound of formula I, and sub-formulas thereof: Formula (I) or a pharmaceutically acceptable salt thereof, where each X independently is O or S, each Y independently is O or S, and each R.sup.1 independently is defined herein; and a liposome composition comprising the cationic lipid of formula I or a sub-formula thereof, and methods of delivering agents, such as nucleic acids including mRNA, in vivo, by administering to a subject the liposome comprising the cationic lipid of formula I or a sub-formula thereof, where the agent is encapsulated within the liposome.

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Various embodiments relate to the field of liposomal formulations for drug delivery, in particular, liposomal formulations for ocular drug delivery. More specifically, various embodiments relate to sustained timolol maleate delivery from liposomes for glaucoma therapy and ocular hypertension.

Compositions are described for direct protein delivery into multiple cell types in the mammalian inner ear. The compositions are used to deliver protein(s) (such as gene editing factors) editing of genetic mutations associated with deafness or associated disorders thereof. The delivery of genome editing proteins for gene editing and correction of genetic mutations protect or restore hearing from genetic deafness. Methods of treatment include the intracellular delivery of these molecules to a specific therapeutic target.

This invention provides a novel delivery means that enables efficient delivery of an active ingredient to a target cell. Such novel delivery means is a liposome for topical administration that consists of dioleylphosphatidylethanolamine (DOPE), phosphatidylcholine, and cationic lipid, that is not modified with PEG, and that is free of cholesterol.

The present invention provides liposomes loaded with chelating agents, pharmaceutical formulations including these liposomes and methods of making chelating agent liposomes. Because the chelating agents are loaded in the liposome with high efficiencies, the liposomes are of use in treatment of metal ion overload in subjects. The liposomes can also contain essential trace metals to compensate for the off target effect of removal of endogenous non-target trace metals by administration of the chelator. The liposomes can include two or more different chelating agents of different structures and affinities for metal ions.

The present invention relates in part to novel cationic lipids and their use, e.g., in delivering nucleic acids to cells.

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.

A method for treating, attenuating or inhibiting an infection and/or disease associated with a SARS virus in a subject is provided that includes administering a pharmaceutical composition to the subject. The composition includes an organosilicone carrier with one or more active substances that block and/or inhibit an ACE2 receptor in a host cell of the subject, the spike protein of a SARS virus and/or internal components of a virion of the SARS virus.