IL300676A - Lipid delivery systems for delivery of oxaliplatin palmitate acetate - Google Patents

Description

LIPID DELIVERY SYSTEMS FOR DELIVERY OF OXALIPLATIN PALMITATE ACETATE TECHNOLOGICAL FIELDThe present disclosure concerns lipid delivery systems for delivery of oxaliplatin palmitate acetate. BACKGROUND Cancers become more widespread as world population is aging [1] . However, marked progress in cancer therapies has been achieved in the last decades. This is mostly due to the development of immunotherapies combined with chemotherapy, and more particularly with platinum (Pt)-based drugs [2,3] , despite significant side effects due to nonspecific damage to normal cells [4] . In order to overcome at least one of the drawbacks associated with Pt-based therapeutics, new Pt-based drugs are explored. Following the clinical success of cisplatin, a Pt(II) drug approved by the FDA in 1979, development of Pt anticancer agents has attracted the attention of researchers. Cleare and Hoeschele [5] have shown that in order for Pt complexes to play an active role in cancer therapy, causing structural distortion of the double stranded DNA, thereby leading to apoptosis, they must be neutral square-planar Pt(II) complexes with two cis-oriented inert amine or chelating diamine ligands and two semi-labile cis-oriented ligands bound to the Pt oxygen donors. As reported by Gibson [6] , despite many years of intensive research, all approved Pt drugs conform to such structure-activity relationship. Although very few Pt agents have been used successfully as drugs, the clinical significance of Pt compounds in cancer therapy is well recognized. Currently, three Pt(II) anticancer drugs are clinically used worldwide in 50-70% of cancer patients [7-9] ; these are cisplatin, carboplatin (approved in 1989), and oxaliplatin (approved in 2002). Unfortunately, despite the resurgence in their use for cancer therapy since 2007 [10] , therapeutic outcomes of Pt(II) drugs are seriously affected owing to severe side effects attributed to the reactivity of the Pt(II) compounds with biological nucleophiles prior to reaching the cancerous tissues, as well as inherent or acquired resistance [11] . Pt(IV) complexes with two additional axial groups may have advantages over the reactive Pt(II) species. They are inert in plasma, may reach cancerous lesions in their Pt(IV) form and be activated into their Pt(II) analogs only inside the cancerous cells. Unfortunately, clinical evaluation of several Platinum(IV) complexes showed rapid elimination, less or equal efficacy than Pt (II) drugs and wide inter- and intra-variable oral bioavailability. Therefore, no Pt(IV) drug has yet reached the market. [12-15] . Oxaliplatin (OXA), a 1,2-diaminocyclohexane (DACH) derivative of cisplatin, is a third-generation Pt(II) drug, active against several lines of colon, ovarian and lung cancer cells. However, the use of Oxaliplatin is limited due to severe side effects such as neurotoxicity, hematologic and gastrointestinal toxicities, neutropenia and intrinsic or acquired resistance [10,16] . OPA (Oxaliplatin palmitate acetate), a Pt(IV) chemical entity derived from OXA and containing both lipophilic and hydrophilic axial ligands, demonstrated at least a 20-time better efficiency in killing cancer cells [17] . OPA showed significantly higher tumor growth inhibition compared to OXA in both orthotopic and xenograft mice tumor models. A detailed description of OPA synthesis has been previously reported [22] . PUBLICATIONS [1] E. Biskup et al., Ann. Palliat. Med. 2019, 9(3), 3.8.20 [2] D. Shaloam et al., Eur. J. Pharmacol. 2014, 740, 364–378 [3] S. Brown et al., Br. J. Cancer 2018, 118, 312–3 [4] C. Mohanty et al., Curr. Drug Deliv. 2011, 8(1), 45– [5] M. J. Cleare et al., Bioinorg. Chem. 1973, 2, 187–2 [6] D. Gibson, J. Inorg. Biochem. 2019, 191, 77- [7] E. Cvitkovic, Semin. Oncol. 1999, 26(6), 647–662 [8] P. J. O'Dwyer et al., Drugs 2000, 59 Suppl 4, 19- [9] V. Dieras et al., Ann. Oncol. 2002, 13(2), 258-2 [10] L. Kelland, Nat. Rev. Cancer 2007, 7(8), 573−5 [11] M. Galanski et al., Curr. Med. Chem. 2005, 12(18), 2075-2094 [12] S. Theiner et al., Dalton Trans. 2018, 47(15), 5252-5258 [13] A. Najjar et al., Curr. Pharm. Des. 2017, 23(16), 2366-23 [14] D. Gibson, Dalton Trans. 2016, 45(33), 12983-129 [15] T. C. Johnstone et al., Chem. Rev. 2016, 116(5), 3436-34 [16] I. Kostova, Anticancer Drug Discov. 2006, 1(1), 1-22 id="p-17" id="p-17" id="p-17" id="p-17" id="p-17" id="p-17" id="p-17" id="p-17" id="p-17" id="p-17" id="p-17" id="p-17"

[17] A. Abu Ammar et al., J. Med. Chem. 2016, 59(19), 9035–90 [18] E. Jerremalm et al., J. Pharm. Sci. 2009, 98(11), 3879-38 [19] P. Allain, Drug Metab Dispos. 2000, 28(11), 1379-13 [20] S. S. Shord et al., Anticancer Res. 2002, 22(4), 2301-23 [21] T. Alcindor et al., Curr Oncol. 2011, 18(1), 18-25 [22] PCT patent publication WO2015/166498 GENERAL DESCRIPTIONOxaliplatin palmitate acetate (OPA) has demonstrated significantly higher tumor growth inhibition compared to OXA in both orthotopic and xenograft mice tumor models of ovarian, pancreatic, lung and liver. However despite its demonstrated capabilities, OPA was prematurely eliminated before cellular uptake. Even when incorporated in a variety of acceptable nanoparticles, proper retention of OPA in the oil core was not observed. Thus, the inventors of the invention disclosed herein have embarked on the development of a suitable delivery system that would hold or contain OPA over long periods of time and efficiently deliver the drug to a patient. Unlike the nanoparticles proposed in the past, it was surprisingly found that only lipid-based nanocarriers could be loaded with significant amounts of OPA while maintaining their stability over time. OPA (Oxaliplatin palmitate acetate) is a Pt(IV) organic complex having the following structural formula: The delivery systems of the present disclosure are based on nanocarriers that comprise at least one lipid material. In the context of the present disclosure, lipids are organic molecules typically comprising a polar "head" and one or more nonpolar "tails", such that they can be arranged spontaneously into organized structures, typically with the polar heads (that are hydrophilic) oriented toward a water-based HN NH PtOOO OOO OO medium and their nonpolar tails (that are hydrophobic) shielded from the water. Such structures may be micelles, bilayers or liposomes. Thus, in one of its aspects, the present disclosure provides a lipid-based delivery system comprising OPA and a lipid-based material, wherein the delivery system is in a form of a nanocarrier. A depiction of the delivery system is provided in Scheme 1 below: Scheme 1 Without wishing to be bound by theory, as shown in Scheme 1 , the arrangement of OPA in the lipid-based structure is highly dependent on its nature. As an amphiphilic molecule, its hydrophilic moieties are located closer to the interface of the liposomes, and its lipophilic palmitic moieties strongly anchored in the bilayers by inter- and intra-molecular attraction forces. This interaction holds OPA in place, preventing its rapid unwanted release. This interaction is referred to herein as "intercalation" or "embedment" or "incorporation". Thus in another aspect, there is provided a lipid-based molecular assembly (herein assembly or nanocarrier) intercalating or incorporating a plurality of OPA molecules. The OPA molecules are intercalated between neighboring lipid molecules as depicted in Scheme 1 . The lipid-based assembly is a molecular assembly of lipid molecules (at least one lipid) selected from phospholipids, glycerolipids, glycerophospholipids, sphingolipids, and mixtures thereof.

In some embodiments, the at least one lipid is a phospholipid, which may be fully saturated, unsaturated or partially hydrogenated. The phospholipid may additionally or alternatively be derived from a natural source or may be partially or fully synthetic. Non-limiting examples of phospholipids include phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), as well as lipid derivatives thereof, such as dimyristoylphosphatidylcholine (DMPC), dipalmitoylphosphatidylcholine (DPPC), distearoylphosphatidylcholine (DSPC), hydrogenated soy phosphatidylcholine (HSPC), dipalmitoylphosphatidylglycerol (DPPG), and others. In dialiphatic phospholipids, the aliphatic chains can be of various chain lengths, comprising a number of carbon atoms ranging between 12 and 22 carbon atoms, e.g., having a C12 to C22 aliphatic chain(s). In some embodiments, the aliphatic chain has at least 18 carbon atoms. Thus, the at least one phospholipid, being fully saturated, unsaturated or partially hydrogenated may be distearoylphosphatidylcholine (DSPC) or hydrogenated soy phosphatidylcholine (HSPC) or mixtures thereof. In some embodiments, the at least one phospholipid is not dipalmitoylphosphatidylcholine (DPPC) or dimyristoylphosphatidylcholine (DMPC). Sphingolipids, by some embodiments, can include lipids having two fatty acid chains, one of which is the hydrocarbon chain of sphingosine. Such also include, for example, glycosphingolipids, which are sphingolipids with one or more sugar residues. Assemblies of the invention are nanocarriers, namely a particulate material that is biocompatible and sufficiently resistant to chemical and/or physical destruction, such that a sufficient amount of the nanocarriers remains substantially intact after administration to a human or an animal and for a time period sufficient to reach the desired target tissue (organ). Generally, the nanocarriers are spherical in shape, having an average diameter of up to 500 nm (nanometers). Where the shape of the nanocarrier is not spherical, the diameter refers to the longest dimension of the nanocarrier. In some embodiments, the nanocarriers have an average diameter of between about 20 nm and about 500 nm. In some embodiments, the average diameter of the nanocarrier is between about 100 and 200 nm. In other embodiments, the average diameter is between about 200 and 300 nm. In further embodiments, the average diameter is between about 300 and 400 nm, the average diameters between 400 and 500 nm. In other embodiments, the average diameter is between about 50 and 400 nm. In further embodiments, the average diameter is between about 50 and 300 nm. In further embodiments, the average diameter is between about 50 and 200 nm. In further embodiments, the average diameter is between about 50 and 100 nm. The nanocarriers may each be substantially of the same shape and/or size. In some embodiments, the nanocarriers have a narrow diameter distribution. In other words, no more than 0.01% to 10% of the particles have a diameter greater than 10% above or below the average diameter noted above, and in some embodiments, such that no more than 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 3, 4, 5, 6, 7, 8, or 9% of the nanocarriers have a diameter greater than 10% above or below the average diameters noted above. OPA may be intercalated or incorporated in the lipid shell of lipid assembly, as depicted in Scheme 1 and as will be further detailed below. Hence, by some embodiments, the assembly or nanocarrier may be in a form of a lipid bilayer assembly (e.g. a liposome), a lipid nanocapsule or a lipid nanosphere. According to some embodiments, the lipids are selected to form a nanocarrier having a lipid bilayer structure. The bilayer structure comprises two layers of lipids, typically arranged such that their hydrophilic heads are appositively directed (directed away from each other) to form external sheets of hydrophilic surfaces, while the hydrophobic tails of the lipids are sandwiched between the two surfaces of the bilayer. The bilayer may be formed or may be provided as a closed spherical bilayer assembly, i.e., as a liposome. Thus, in some embodiments, the molecular assembly or nanocarrier is in the form of a liposome. The liposome is a closed bilayer structure made of the at least one lipid, and OPA intercalated or incorporated between the lipid molecules in the assembly, as exemplified by the structure of Scheme 1 . Without wishing to be bound by theory, OPA is lipophilic in nature, and hence may be associated with the lipid bilayer, e.g. incorporated, intercalated or embedded within the lipid bilayer or partially dissolved therein (dispersed at the molecular level and/or partly dispersed as small molecule aggregates within the bilayer). Typically, the liposome is a unilamellar liposome, namely structured out of a single lipid bilayer. However, multilamellar liposomes, being liposomes constructed out of two or more concentric lipid bilayers, can also be used in the context of the present disclosure.

According to some embodiments, the bilayer structure (e.g. the liposome) comprises at least one phospholipid. According to other embodiments, the bilayer structure comprises at least one phospholipid and at least one sterol. Sterols are steroid alcohols and are typically considered a type of lipid. Sterols are derived from steroids, and have a fused rings core structure in which one of the hydrogen atoms is substituted with a hydroxyl group at the 3-position of the A-ring. Sterols are added to the lipids forming the lipid bilayer typically to decrease the bilayer permeability and hence increase its stability. The sterols may be selected from cholesterol, cholesteryl, cholesteryl hemisuccinate, cholesteryl sulfate and other derivatives of cholesterol and combinations thereof . According to some embodiments, the liposome comprises at least one lipid and at least one sterol, wherein the weight ratio between the lipids and the sterols in a nanocarrier is in the range of between about 1:0.05 and about 1:5. In other embodiments, the weight ratio between the lipids and the sterols in nanocarrier may be in the range of between about 1:0.1 and about 1:5, between about 1:0.2 and about 1:5, between about 1:0.3 and about 1:5, between about 1:0.4 and about 1:5, between about 1:0.5 and about 1:5, between about 1:0.6 and about 1:5, between about 1:0.7 and about 1:5, between about 1:0.8 and about 1:5, between about 1:0.9 and about 1:5, or even between about 1:1 and about 1:5. In some other embodiments, the weight ratio between the lipids and the sterols in nanocarrier may be in the range of between about 1:0.05 and about 1:4.5, between about 1:0.05 and about 1:4, between about 1:0.05 and about 1:3.5, between about 1:0.05 and about 1:3, between about 1:0.05 and about 1:2.5, between about 1:0.05 and about 1:2, between about 1:0.05 and about 1:1.5, or even between about 1:0.05 and about 1:1. In further embodiments, the weight ratio between the lipids and the sterols in nanocarrier may be in the range of between about 1:0.1 and about 1:4.5, between about 1:0.3 and about 1:4, between about 1:0.5 and about 1:3, or even between about 1:0.7 and about 1:2.5. The lipid composition of the bilayer may further comprise one or more surfactants. The surfactant(s) can be hydrophilic, hydrophobic, amphiphilic, cationic, anionic, or non-ionic, depending on the lipids used. According to some embodiments, the lipid composition comprises at least one non-ionic surfactant. According to some embodiments, the surfactant(s) may be selected from polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monooleate, and polyoxyeyhylene esters of saturated and unsaturated castor oil, ethoxylated monglycerol esters, ethoxylated fatty acids and ethoxylated fatty acids of short and medium and long chain fatty acids and others. The surfactant(s) may be at least one of the polyoxyethylenes, ethoxylated (20EO) sorbitan mono laurate (T20), ethoxylated (20EO) sorbitan monostearate/palmitate (T60), ethoxylated (20EO) sorbitan mono oleate/linoleate (T80), ethoxylated (20EO) sorbitan trioleate (T85), castor oil ethoxylated (20EO to 40EO); hydrogenated castor oil ethoxylated (20 to 40EO), ethoxylated (5-40 EO) monoglyceride stearate/plamitate, polyoxyl 35 and 40 EOs castor oil. According to other embodiments, the hydrophilic surfactant may be selected from polyoxyl castor oil, polysorbate 40 (Tween 40), polysorbate 60 (Tween 60), polysorbate (Tween 80), Mirj S40, oleoyl macrogolglycerides, polyglyceryl-3 dioleate, ethoxylated hydroxyl stearic acid (Solutol HS15), sugar esters such as sucrose monooleate, sucrose monolaurate, sucrose mono stearate, polyglycerol esters such as decaglycerol monooleate or monolaurate, hexaglycerol monolaurate or mono oleate, etc. In some embodiments, the surfactant may be at least one of polyethylene glycol 15-hydroxystearate (Solutol HS 15), polysorbate 40 (Tween 40), polysorbate (Tween 60), and polysorbate 80 (Tween 80). The lipid composition may further comprise, by some embodiments, at least one oil at a concentration which does not affect the bilayer structure of the nanocarrier. The at least one oil may be selected from mineral oil, paraffinic oils, vegetable oils, glycerides, fatty acids, esters of fatty acids, liquid hydrocarbons and alcohols thereof, and others. According to some embodiments, the oil may be selected from medium-chain triglycerides (MCT), long chain triglycerides such as fish oil, safflower oil, soybean oil, cottonseed oil, sesame oil, castor oil, olive oil, and others. Alternatively, the bilayered nanoparticles may be of a substantially uniform composition not featuring a distinct core/shell structure. These nanocarriers are herein referred to as lipid nanospheres, and comprise a lipid matrix into which OPA is embedded. The lipid matrix of such nanospheres can comprise one or more lipids as disclosed herein. The lipid matrix may also comprise small quantities of injectable oils, e.g. at a quantity between about 0.1 wt% and about 10 wt% of the lipid matrix total weight. Oils which can be used in parenteral formulations include petroleum, animal, vegetable, or synthetic oils. Specific examples of oils include peanut oil, soybean oil, sesame oil, cottonseed oil, corn oil, olive oil, fish oil, safflower oil, castor oil. Suitable fatty acids for use in parenteral formulations in small quantities are unsaturated fatty, oleic acid (18: 1), linoleic (18: 2) and linolenic acid (18:3), long- chain omega-3 fatty acids (e.g. docosahexaenoic acid (DHA) or eicosapentaenoic acid (EPA)) and others, as well as medium chain fatty acid from C8 to C12, octanoic acid, caprylic acid, etc. In some embodiments, the nanocarriers may be surface-associated with at least one non-active agent. The term surface-associated means a chemical or a physical association of a nanocarrier component(s) to a non-active agent(s) that extends outwards from the surface of the nanocarrier. The term refers to any association between the surface of the nanocarrier and the non-active agent, e.g. ionic bonding, electrostatic bonding, covalent bonding, dipole-dipole interaction, hydrophilic interaction, van der Waal's interaction, hydrogen bonding, physical anchoring, adsorption, or any other suitable attachment mechanism of the non-active agent to the surface of the nanocarrier. The non-active agent (non-therapeutic agent) may be selected to modulate at least one characteristic of the nanocarrier, such characteristic may for example be one or more of size, polarity, hydrophobicity/hydrophilicity, electrical charge, reactivity, chemical stability, clearance rate, distribution, targeting and others. In some embodiments, the non-active agent is a substantially linear carbon chain having at least 5 carbon atoms, and may or may not have one or more heteroatoms in the linear carbon chain. In other embodiments, the non-active agent is selected from polyethylene glycols (PEG) of varying chain lengths, fatty acids, amino acids, aliphatic or non-aliphatic molecules, aliphatic thiols, aliphatic amines, and others. The non-active agent may or may not be charged. According to some embodiments, the non-active agent is polyethylene glycol (PEG). In such embodiments, the PEG may have an average molecular weight in the range of between about 2,000 and 5,000 Da (Daltons). In other embodiments, the nanocarrier may be non-PEGylated, i.e. the non-active agent is different from PEG. By some embodiments, the nanocarrier is lyophilized.

At times, especially when lyophilization of the nanocarriers is desired, a cryo-protectant may be added to protect and improve the stability of the nanocarriers during the lyophilization process. According to some embodiments, the cryo-protectant may be selected from lactose, maltose, trehalose, sorbitol, mannitol, sulfobutyl-ether-β-cyclodextrin, polyvinyl alcohols, high molecular weight poloxamers, high molecular weight hyaluronic acid, etc. In some embodiments, in a system of the invention, the assembly constructed of lipid molecules comprises a phospholipid that is distearoylphosphatidylcholine (DSPC) or hydrogenated soy phosphatidylcholine (HSPC) or mixtures thereof. This system may be lyophilized. Thus, a liposome is provided that comprises at least one phospholipid and OPA, wherein said at least one phospholipid is distearoylphosphatidylcholine (DSPC) or hydrogenated soy phosphatidylcholine (HSPC) or mixtures thereof. In some embodiments, the liposome is surface decorated with a plurality of non-active materials, as defined, e.g., polyethylene glycol (PEG). In some embodiments, the liposome comprises 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol, OPA and N-(Carbonyl-methoxypolyethyl-eneglycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE-PEG2000), wherein optionally the molar ratio of DSPC:cholesterol:OPA:DSPE-PEG2000 is 5:3:2:0.5, or 5:3:1:0.5, 5:3:0.75:0.5, or 5:3:0.5:0.5 respectively. In some embodiments, the liposome comprises hydrogenated soy phosphatidylcholine (HSPC), Cholesterol, OPA and (N-(Carbonyl-methoxypolyethyl-eneglycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine) (DSPE-PEG2000), wherein optionally the molar ratio of HSPC:Cholesterol:OPA:DSPE-PEG2000 is 5:3:2:0.5, or 5:3:1:0.5, 5:3:0.75:0.5, or 5:3:0.5:0.5 respectively. The liposome may comprise hydrogenated soy phosphatidylcholine (HSPC), Cholesterol, OPA and dipalmitoylphosphatidylglycerol sodium salt (DPPG-Na), optionally at a molar ratio of 3:2:1:1. As exemplified herein the liposome may be prepared by thin-film hydration or by ethanol injection, as exemplified herein. By another one of its aspects, this disclosure provides oxaliplatin palmitate acetate (OPA) loaded lipid-based nanocarrier. According to another aspect, there is provided a lipid-based nanocarrier consisting of a lipid material and oxaliplatin palmitate acetate (OPA).

In some embodiments, the nanocarrier is in the form of a lipid bilayer or a liposome. In other embodiments, the nanocarrier is in the form of a uni-lamellar liposome. By some embodiments, the lipid is selected from at least one phospholipid, at least one sterol, and combinations thereof. According to some embodiments, the lipid formulation comprises at least one phospholipid and at least one sterol. By an embodiment, the weight ratio between the lipids and the sterol is in the range of between about 1:0.05 and about 1:5. According to other embodiments, the nanocarrier is surface-associated with at least one non-active agent, e.g. polyethylene glycols (PEG). In another one of its aspects, this disclosure provides a composition comprising a lipid-based delivery system or a lipid-based nanocarrier as described herein. Typically, the composition is a pharmaceutical composition. As used herein, pharmaceutical composition comprises a therapeutically effective amount of OPA, together with suitable diluents, preservatives, solubilizers, emulsifiers, adjuvant and/or carriers. Such compositions are liquids or lyophilized or otherwise dried formulations and include diluents of various buffer content (e.g. tris-HCL, acetate, phosphate), pH and ionic strength, additives such as albumin or gelatin to prevent absorption to surfaces, surfactants (e.g. Tween 20, Tween 80, Pluronic F68, bile acid salts), solubilizing agents (e.g. glycerol, polyethylene glycerol), anti-oxidants (e.g. ascorbic acid, sodium metabisulfite), preservatives (e.g. thimerosal, benzyl alcohol, parabens), bulking substances or tonicity modifiers (e.g. lactose, mannitol), etc. Such compositions will influence the physical state, solubility, stability, rate of in vivo release, and rate of in vivo clearance. Controlled or sustained release compositions include formulation in lipophilic depots (e.g. fatty acids, waxes, oils). Formulations suitable for parenteral administration include aqueous and non-aqueous formulations, isotonic sterile injection solutions, which can contain anti-oxidants, buffers, bacteriostats, and solutes that render the formulation isotonic with the blood of the intended recipient, and aqueous and non-aqueous sterile suspensions that include suspending agents, solubilizers, thickening agents, stabilizers, and preservatives. The compound can be administered in a physiologically acceptable diluent in a pharmaceutical carrier, such as a sterile liquid or mixture of liquids, including water, saline, aqueous dextrose and related sugar solutions, an alcohol, such as ethanol, isopropanol, or hexadecyl alcohol, glycols, such as propylene glycol or polyethylene glycol, glycerol ketals, such as 2,2-dimethyl-1,3-dioxolane-4-methanol, ethers, such as poly(ethyleneglycol) 400, an oil, a fatty acid, a fatty acid ester or glyceride, or an acetylated fatty acid glyceride with or without the addition of a pharmaceutically acceptable surfactant, such as a soap or a detergent, suspending agent, such as pectin, carbomers, methylcellulose, hydroxypropylmethylcellulose, or carboxymethylcellulose, or emulsifying agents and other pharmaceutical adjuvants. Oils, which can be used in parenteral formulations include petroleum, animal, vegetable, or synthetic oils. Specific examples of oils include peanut oil, soybean oil, sesame oil, cottonseed oil, corn oil, olive oil, petrolatum oil, and mineral oil. Suitable fatty acids for use in parenteral formulations include oleic acid, stearic acid, and isostearic acid. The lipid-based delivery systems of the present disclosure may be made into injectable formulations. The requirements for effective pharmaceutical carriers for injectable compositions are well known to those of ordinary skill in the art. See Pharmaceutics and Pharmacy Practice, J.B. Lippincott Co., Philadelphia, Pa., Banker and Chalmers, eds., pages 238-250 (1982), and ASHP Handbook on Injectable Drugs, Toissel, 4th ed., pages 622-630 (1986). In some embodiments, the composition is suitable for administration by injection. In some embodiments, the composition is suitable for intravenous administration. In other embodiments, the composition is suitable for topical administration, i.e. directly onto at least a portion of a subject's skin (human's or non-human's skin) so as to achieve a desired systemic or local effect. A topical composition comprising the delivery system or nanocarrier of this disclosure may be in any suitable form, e.g. a cream, a lotion, an ointment, an emulsion, a gel, a suspension, a solution, a liquid, an aerosol, a foam, etc. In further embodiments, the composition is suitable for ocular administration, e.g. administrated topically to the conjunctiva or the eyelid or administrated parenterally, e.g. intraocular injection to the anterior, posterior and vitreous chambers. The composition may be of any suitable topical delivery form, such as a solution, a suspension, a paste, a cream, a foam, a gel, an ointment, a spray, drops, etc.

By another aspect, there is provided a lipid-based delivery system, a lipid-based nanocarrier, or a composition as described herein, for use in delivery of OPA to a patient in need thereof. By a further aspect, there is provided a lipid-based delivery system, a nanocarrier or composition as described herein, for use in treating or delaying progression of a proliferative disorder. In yet another aspect, there is provided use of a lipid-based delivery system, a nanocarrier, or a composition as described herein, for the preparation of a medicament for treating or delaying progression of a proliferative disorder. By yet a further aspect of the disclosure provides a method for delivering OPA to a subject in need thereof, the method comprising administering an effective amount of a lipid-based delivery system, a nanocarrier, or a composition as described herein. A further aspect of the disclosure provides a method for treating or delaying or preventing the progression of a proliferative disorder, the method comprising administering an effective amount of a lipid-based delivery system, a nanocarrier, or a composition as described herein. The term proliferative disorders encompass diseases or disorders that effect a cellular growth, differentiation or proliferation processes. In some embodiments, the proliferation disorder is cancer. The term cancer as used herein encompasses any neoplastic disease which is characterized by abnormal and uncontrolled cell division causing malignant growth or tumor. Cancer may refer to either a solid tumor or tumor metastasis. Non-limiting examples of cancer are ovary cancer, and pancreatic cancer, squamous cell cancer (e.g. epithelial squamous cell cancer), lung cancer including small-cell lung cancer, non-small cell lung cancer, adenocarcinoma of the lung and squamous carcinoma of the lung, cancer of the peritoneum, hepatocellular cancer, gastric or stomach cancer including gastrointestinal cancer, pancreatic cancer, glioblastoma, cervical cancer, ovarian cancer, liver cancer, bladder cancer, hepatoma, breast cancer, colon cancer, rectal cancer, colorectal cancer, endometrial or uterine carcinoma, salivary gland carcinoma, kidney or renal cancer, prostate cancer, vulval cancer, thyroid cancer, hepatic carcinoma, anal carcinoma, penile carcinoma, as well as head and neck cancer. Solid cancers appear in many forms, for example, breast cancer, prostate cancer, sarcomas, and skin cancer. One form of skin cancer is melanoma.

In some embodiments, the cancer is selected from lung cancer, colon cancer, pancreatic cancer and ovarian cancer. The term treatment as used herein refers to the administering of a therapeutic amount of the composition of the present disclosure which is effective to ameliorate undesired symptoms associated with a disease, to prevent the manifestation of such symptoms before they occur, to slow down the progression of the disease (also referred to herein as "delaying the progression"), slow down the deterioration of symptoms, to enhance the onset of remission period, slow down the irreversible damage caused in the progressive chronic stage of the disease, to delay the onset of said progressive stage, to lessen the severity or cure the disease, to improve survival rate or more rapid recovery, or to prevent the disease from occurring or a combination of two or more of the above. The term effective amount as used herein is determined by such considerations as may be known in the art. The amount must be effective to achieve the desired therapeutic effect as described above, depending, inter alia, on the type and severity of the disease to be treated and the treatment regime. The effective amount is typically determined in appropriately designed clinical trials (dose range studies) and the person versed in the art will know how to properly conduct such trials in order to determine the effective amount. As generally known, an effective amount depends on a variety of factors including the affinity of the ligand to the receptor, its distribution profile within the body, a variety of pharmacological parameters such as half-life in the body, on undesired side effects, if any, on factors such as age and gender, etc. In some embodiments, the effective amount of the OPA is provided in the form of a lipid-based delivery system, a nanocarrier, or composition as disclosed herein, and administrated by one or more of the following routes: dermal, ocular, rectal, transmucosal, transnasal, intestinal, parenteral, intramuscular, subcutaneous, intramedullary injections, intrathecal, direct intraventricular, intravenous, intraperitoneal, intranasal, or intraocular injections. The term subject refers to a mammal, human or non-human. The phrases "ranging/ranges between" a first indicate number and a second indicate number and "ranging/ranges from" a first indicate number "to" a second indicate number are used herein interchangeably and are meant to include the first and second indicated numbers and all the fractional and integral numerals there between. It should be noted that where various embodiments are described by using a given range, the range is given as such merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all the possible sub-ranges as well as individual numerical values within that range. As used herein, the term about is meant to encompass deviation of ±10% from the specifically mentioned value of a parameter, such as temperature, pressure, concentration, etc. BRIEF DESCRIPTION OF THE DRAWINGSIn order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: Figs. 1A-1G are cryo-TEM images of Blank Lip.1 ( Figs. 1A-1C ) and OPA Lip.1. ( Figs. 1D-1G ). Lipid composition of DSPC:cholesterol:OPA:DSPE-PEG2000 at ratios 5:3:1:0.5. Figs. 2A-2D are TEM micrographs of uranyl acetate negatively stained non-PEGylated NCs at different areas of the grid: Freshly prepared samples NC7 ( Figs. 2A-2B ), NC7 nanocapsules ( Fig. 2C ), NE3 nanoemulsion ( Fig. 2D ) - after 3 months of lyophilization and reconstitution of the aqueous dispersion. Figs. 3A-3B are cryo-TEM micrographs of non-PEGylated liposomes containing OPA before ( Fig. 3A ) and after ( Fig. 3B ) lyophilization. Lipids composition was DSPC:Chol at ratio 2:1. Figs. 4A-4B are cryo-TEM micrographs of PEGylated liposomes containing OPA, before ( Fig. 4A ) and after ( Fig. 4B ) lyophilization. Lipids composition was HSPC:Chol:DSPE-PEG2000 at ratio 12:4:3. (scale bar = 100 nm). Figs. 5A-5B are cryo-TEM micrographs of non-PEGylated liposomes containing OPA before ( Fig. 5A ) and after ( Fig. 5B ) lyophilization. Lipids composition was DSPC:Chol at ratio 2:1. Figs. 6A-6B show mean plasma concentration of OPA ( Fig. 6A ) and OXA ( Fig. 6B ) following 1.25, 5 and 20 mg/kg IV administrations. Values are mean ± SD. N=3. Fig. 7A-7B show Pt distribution in the rat (N=4) in the rat (n=4) whole blood, plasma and hematocrit after applying OPA Solution IV dosage equivalent to 5 mg/kg OPA ( Fig.7A ) and OPA Liposomes PEGylated (OPA-LIP5 LYO) IV dosage equivalent to 5 mg/kg OPA ( Fig.7B ). Figs. 8A-8B show mean plasma concentration of OPA ( Fig. 8A ) and oxaliplatin as metabolite ( Fig. 8B ), following 7.5 mg/kg IV administrations of OPA-containing liposomes. Values are mean ± SD. N=3. Fig. 9 shows Pt (µg/ml) in rat (n=3) plasma after applying various formulations of OPA, IV dosage equivalent to 5 mg/kg OPA. Fig. 10 shows the mean whole blood and plasma Pt Concentration (µg/mL) following dual IV administrations of OPA-containing mPEG-liposomes (of OPA-LIP-(LYO), 5 mg/kg at t=0 and 72 hours). Dashed lines are estimated Pt levels base on previous data. Values are mean ± SD. N= Figs. 11A-11D show plasma concentrations (ng/mL) and organ bio-distribution (ng/g) of OPA ( Figs. 11A-11B ) and one of its metabolites, oxaliplatin ( Figs. 11C-11D ), 1 and 4 hours after a single IV administration of mPEG-liposomal formulation (60 mg/kg), Bare-liposomal formulation (60 mg/kg) and OPA solution (15 mg/kg) to BALB/c female mice. N=3, Values are mean ± SE. Fig. 12 shows mean body weights of mice in different groups during treatment. Fig. 13 shows mean body weight changes of mice in different groups during treatment. Fig. 14 shows mean body weights of mice in different groups during treatment. Fig. 15 shows mean body weight changes of mice in different groups during treatment. Fig. 16 shows tumor volumes of mice in different groups during treatment of Hep3B model in balb/c nude mice. Fig. 17 shows mean body weights of mice in different groups during treatment of Hep3B model in balb/c nude mice. Fig. 18 shows mean body weight changes of mice in different groups during treatment of Hep3B model in balb/c nude mice. Fig. 19 shows survival curves of mice in different groups during treatment in mouse liver cancer model Hep3B. Fig. 20 shows tumor volumes of mice in different groups during treatment in mouse liver cancer model Hep3B.

Fig. 21 shows mean body weights of mice in different groups during treatment in mouse liver cancer model Hep3B. Fig. 22 shows mean body weight changes of mice in different groups during treatment in mouse liver cancer model Hep3B. Fig. 23 shows survival curves of mice in different groups during treatment in mouse liver cancer model Hep3B. Figs. 24A-D show how OPA liposomes and Avastin combination arrest tumor growth and extends survival in ovarian cancer xenograft orthotopic mouse model. For tumor development, luciferase transfected SKOV3-luc cells (2 × 106 cells in 100 μL of PBS) were injected into intraperitoneal cavity of mice. The Tumor growth was measured and quantified by IVIS every week. ( Fig. 24A ) Longitudinal detection and quantification of tumor growth. Tumor size is expressed as luminescence intensity of the dorsal images, expressed in radiance units (photons/s/cm2/sr). Results are presented as mean ± S.E.M. ( Fig. 24B ) Body weight follow-up beginning from tumor inoculation (day 0) through the study period. Changes were recorded as a percentage of the initial body weight observed on the day of tumor cells injection (100% at day 0). ( Fig. 24C ) Kaplan-Meier survival curve from tumor cells injection day until death. ( Fig. 24D ) Bioluminescent monitoring of orthotopic ovarian SKOV3-luc cancer cells expressing the luciferase gene. Bioluminescent images were acquired 10 min after intraperitoneal injection with luciferin. Fig. 25 shows an illustration of the thin-film hydration method for the preparation of OPA Liposomes. Fig. 26is an illustration of the ethanol injection method for the preparation of OPA Liposomes. Figs. 27A-B provide Cryo-TEM images of Blank Lip.1. Fig. 27A ) image at 1 µm scale and Fig. 27B ) image at 100 nm scale. Figs. 28A-B provide Cryo-TEM images of OPA Lip.1. Fig. 28A ) image at µm scale and Fig. 28B ) image at 100 nm scale. DETAILED DESCRIPTION OF EMBODIMENTS MATERIALS AND METHODSIn the following experimental sections, various lipid components were utilized: Lipoid PC 14:0/14:0 (DMPC), Lipoid PC 16:0/16:0 (DPPC), Lipoid PC 18:0/18:0 (DSPC), Lipoid PE 18:0/18:0-PEG 2000 (DSPE-mPEG2000, sodium salt), Lipoid PG 16:0/16:0 (DPPG, sodium salt), Lipoid S PC-3 (HSPC) (all manufactured by Lipoid GmbH). Preparation of OPA liposomes using this-film hydration methodLipid film preparation using tert-butanol All the lipids of the OPA liposome preparation and OPA were weighed (see Results section below) and transferred to a round-bottom flask. Tert-butanol was added to the lipids' mixture and heated for few minutes at 50˚C until all ingredients were completely dissolved. Afterwards, the round-bottom flask was frozen under rotation in ice cold ethanol bath, followed by an overnight lyophilization. Consequently, a thin film of lipid cake was obtained and further hydrated, with an appropriate amount of 5% dextrose solution or water pre-heated to 60˚C, under rotation for 1 hour at 60˚C. After the rotation, large multilamellar vesicles (MLV) were obtained and further down-sized to small unilamellar vesicles (SUV) using tip-sonication homogenization (Ultrasonic processor, VCX 750, Sonics & Materials, Inc.) for 6 min, at 40% amplitude. Lipid film preparation using chloroform All the lipids of the OPA liposome preparation and OPA were weighed (see Results section below) and transferred to a round-bottom flask. Chloroform was added to the lipids' mixture. After a complete dissolution of all ingredients, chloroform was evaporated using a Rotary-evaporator instrument at 100 rpm without heating. Consequently, a thin lipid film was formed on the round-bottom flask and was further hydrated, with an appropriate amount of 5% dextrose solution or water pre-heated to 60˚C, under rotation for 1 hour at 60˚C. After the rotation, large multilamellar vesicles (MLV) were obtained and were further down-sized to small unilamellar vesicles (SUV) using tip-sonication homogenization (Ultrasonic processor, VCX 750, Sonics & Materials, Inc.) for 6 min, at 40% amplitude. Preparation of OPA liposomes by ethanolic injectionPEGylated and Non-PEGylated liposomes were prepared according to the well-established ethanolic injection method ( Table 1 ). The organic phase was 10 ml ethanol and the aqueous phase was 20 ml water. OPA, hydrogenated soy phosphatidylcholine (HSPC), N-(carbonyl-methoxypolyethylene glycol 2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine sodium salt (MPEG 2000-DSPE), and cholesterol were dissolved in 10 ml ethanol.

The aqueous phase and organic phase were heated to 60°C. The organic phase was added dropwise to the aqueous phase while stirring at 800 rpm on a magnetic stirrer. Immediately after addition the mixture was moved to a stirrer at room temperature and continuously stirred at 800 rpm for 30 minutes. Ethanol was evaporated using a rotary evaporator. Liposomes were stored at 4°C. Immediately after addition, the mixture was moved to a stirrer at room temperature and continuously stirred at 800 rpm for 30 minutes. Ethanol was evaporated using a rotary evaporator. Liposomes were stored at 4°C. Table 1:OPA liposome formulations (PEGylated and non-PEGylated) Formulation Organic phase – ethanol (10 ml) Aqueous phase (20 ml) Stability (h)OPA (mg) DSPC (mg) MPEG 2000-DSPE (mg) Cholesterol (mg) water OPA-LIP-NonPEG 20 120 - 60 20 OPA-LIP-PEGylated 50 90 30 40 20 Preparation of OPA nanocapsules PEGylated and Non-PEGylated OPA nanocapsules were prepared according to the well-established solvent interfacial deposition method ( Table 2 ). OPA or [Pt(DACH)(OAc)(OPal) (ox)], PLGA/PEG-PLA, Tween 80 and MCT were dissolved in 9 ml acetone. 50 mg/ml Lipoid E80 solution was prepared in methanol. 1 ml of this solution was mixed with 9 ml acetone with the dissolved ingredients and was stirred at 1000 rpm in a magnetic stirrer for 15 min. The organic phase was added dropwise into 20 ml of aqueous phase of Solutol®HS 15 by a needle with an inner diameter of 0.3 mm and was stirred at 1500 rpm for 30 minutes, followed by the evaporation of acetone using a Rota evaporator (Rotavapor, R300, BUCHI, Switzerland). Large aggregates in the suspension were precipitated by centrifugation at 4 °C, 4000 rpm for 10 min. the supernatant was collected and the pH of the formulation was adjusted to 7.4.

Table 2:OPA nanocapsule formulations (PEGylated and non-PEGylated) Formulation Organic phase – acetone (10 ml) Aqueous phase (20 ml) Stability (h) OPA (mg) Lipoid E(mg) MCT (mg) PEG-PLA 6 (mg) PLGA, 7-KDa (mg) Tween(mg) Solutol HS(mg) OPA-NC-nonPEG 50 100 - 15 100 50 OPA-NC-PEGylated 50 100 15 - 100 50 Lyophilization of formulations Lyophilization was carried out in Epsilon 2-6d Martin Christ lyophilizer (Gef., Germany) to obtain dry powder. Various sugars were investigated as possible cryo- protectant for the freeze-drying process of OPA NCs and liposomes e.g. Mannitol, sucrose, trehalose, dextrose, lactose, captisol and hydroxypropyl-β-cyclodextrin (HPβCD) at various concentrations of 2, 3, 4, 5, 6% w/w or at different weight ratios of 1:0.25, 1:0.5, 1:1, 1:2, 1:4 (liposome ingredients:cryoprotectant). The sugars were weighed and directly added to the formulation batches and stirred on magnetic stirrer for 10 min to mix or were added as a solution to the liposome formulation. At the end of the drying process, the vials were rapidly stoppered under vacuum and stored at room temperature. Determination of drug contentTo determine the OPA content in NCs and liposomes prepared by the ethanolic injection method, it was dissolved in ethanol and diluted with acetonitrile, and the OPA concentration was determined using analytical Dionex HPLC consisting of Dionex 3000 Ultimate auto sampler. Separation was performed on a reverse phase C18 column (5µm, 4.6×250 mm) from Agela Technologies, USA. The mobile phase consisted of water: acetonitrile (10:90 v/v), eluted at a flow rate of 1.0 ml/min. The effluent was monitored using a UV detector at 220 nm. To determine the OPA content in the liposomes prepared by the thin-film hydration method, liposome sample was diluted ×20 with methanol, and the OPA concentration was determined using analytical Thermo HPLC consisting of Thermo Scientific Dionex UltiMate 3000 Autosampler. Separation was performed on a reverse phase C18 column (5μm, 250×4.6mm, Xselect CSH, Waters, USA). The mobile phase consisted of acetonitrile (Eluent A) and water (Eluent B), at a gradient elution (from 60/40 A/B to 80/20 A/B), at a flow rate of 1mL/min. The effluent was monitored using a UV detector at 220 nm. Transmission electron microscopy (TEM) of non-PEGylated NCsMorphological images were recorded on a TEM system (CM12 TEM, Philips) with an acceleration voltage 100 kV after negative staining using 2% uranyl acetate. A diluted suspension of the formulation (1:10) in water was dropped on carbon-coated copper grids (300-mesh), dried and analyzed. Cryogenic TEM (cryo-TEM)Cryo-TEM enables direct imaging of nanostructures in their native, aqueous, environment. The samples were prepared by applying a 3 μL drop onto a glow-discharge TEM grid (300 mesh Cu Lacey substrate, Ted Pella, Ltd.). The excess liquid was blotted, and the specimens were vitrified by a rapid plunging into liquid ethane precooled with liquid nitrogen using Vitrobot Mark IV (FEI). The vitrified samples were examined at -177 °C using FEI Tecnai 12 G2 TWIN TEM operated at 120 kV and equipped with a Gatan model 626 cold stage. The images were recorded by a 4K × 4K FEI Eagle CCD camera in low-dose mode (to reduce radiation damage). TIA (Tecnai Imaging & Analysis) software was used to record the images. In vitro cytotoxicityThe in vitro cytotoxic effect of OPA, free and in liposomes formulation in comparison to the parent molecule OXA, was evaluated in four cancerous cell lines: BxPC-3 luc (human pancreatic cancer), Scl-1 (Human skin squamous cell cancer), SKOV-3 luc (Human ovarian cancer) and CNS-1 (Rat CNS glioblastoma). Experimental design Cytotoxicity was determined in the various cancer cell lines using the colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) assay. Briefly, cells of the different cell lines were seeded in a sterile 96-well plate (3000 cells/well) in the appropriate growth medium and allowed to attach overnight. Then, the cells were treated with the test drugs (OXA, OPA and OPA liposomes) at increasing drug concentrations (0-7 μM for OPA and OPA liposomes, and 0-25 μM for OXA) at 37°C under 5% CO2 for 72 hr. MTT assay Cytotoxicity was determined by the colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) assay. At the end of the 72 hr-long incubation, cells were incubated in MTT solution (0.5 mg/mL) in PBS for 1 hr at 37°C. The resulting precipitated formazan was extracted in dimethylsulfoxide (DMSO) and the absorbance was measured at 570 nm and at 690 nm. The difference (OD 570nm – OD 690nm) reflects cell viability. Results were normalized to the untreated samples defined as 100% and shown as mean ± S.D. In vitro determination of blood to plasma ratio of OPA test in humanExperimental design Fresh human blood was collected from at least two donors, and Spiked with test compound at 1 μM in triplicates. The blood-compound mixtures were incubated with gentle shaking for 60 minutes at 37°C, and after incubation, aliquots of blood and plasma were removed for determination of analytes. Relative concentrations of OPA and OXA in samples were assessed based on peak area ratio versus internal standard, and the ratio of compound concentrations in whole blood over plasma (KB/P), the respective drug concentrations in the erythrocytes to plasma (KE/P), and %Recovery in blood were calculated. Data analysis The ratio of compound concentrations in whole blood over plasma (KB/P), the respective drug concentrations in the erythrocytes to plasma (KE/P), and %Recovery in blood are calculated by the following equations:

Claims (50)

1.CLAIMS: 1. A lipid-based delivery system of oxaliplatin palmitate acetate (OPA), the delivery system comprising a lipid-based assembly and OPA.

2. The delivery system of claim 1, wherein said lipid-based assembly comprises at least one lipid selected from phospholipids, glycerolipids, glycerophospholipids, sphingolipids, and mixtures thereof.

3. The delivery system of claim 1 or 2, wherein the assembly is in the form of a lipid bilayer.

4. The delivery system of claim 3, wherein the assembly is a liposome.

5. The delivery system of claim 4, wherein the liposome is a unilamellar liposome.

6. The delivery system of any one of the preceding claims, wherein said OPA is intercalated in the assembly.

7. The delivery system of claim 3, wherein said OPA is intercalated in said lipid bilayer.

8. The delivery system of any one of claims 1 to 7, wherein said at least one lipid is at least one phospholipid.

9. The delivery system of any one of claims 1 to 8, wherein the assembly comprises at least one phospholipid and at least one sterol.

10. The delivery system of claim 9, wherein the weight ratio between the phospholipids and the sterols in assembly is in the range of between about 1:0.05 and about 1:5.

11. The delivery system of claim 1, wherein the assembly is a lipid nanosphere, said nanosphere comprising a lipid matrix and said OPA is embedded within said matrix.

12. The delivery system of claim 1, wherein the assembly is a nanocapsule having a shell composition comprising said at least one lipid, the shell incorporating said OPA, wherein said nanocapsule is free of a polymeric material.

13. The delivery system of claim 12, wherein said at least one polymeric material is selected from polylactic acid (PLA), polyglycolic acid (PGA), polyhydroxybutyrate, polycaprolactone, poly(orthoesters), polyanhydrides, polyamino acid, poly(alkyl cyanoacrylates), polyphophazenes, copolymers of (PLA/PGA) and asparate or polyethylene-oxide (PEO), and/or copolymers or mixtures thereof.

14. The delivery system of any one of claims 1 to 13, wherein said assembly being surface-associated with at least one non-active agent.

15. The delivery system of claim 14, wherein said at least one non-active agent is selected to modulate at least one characteristic of the nanocarrier, said characteristic being selected from size, polarity, hydrophobicity/hydrophilicity, electrical charge, reactivity, chemical stability, clearance rate, distribution and targeting.

16. The delivery system of claim 14 or 15, wherein the non-active agent is polyethylene glycols (PEG).

17. The delivery system of any one of claims 1 to 14, wherein said assembly is non-PEGylated.

18. The delivery system of any one of claims 1 to 17, wherein said assembly having a mean diameter of at most 500 nm.

19. The delivery system of claim 18, wherein said assembly having a mean diameter of between about 20 nm and about 500 nm.

20. The delivery system of any one of claims 1 to 19, further comprising at least one cryoprotectant.

21. The delivery system of any one of claims 1 to 20, wherein the assembly is lyophilized.

22. An oxaliplatin palmitate acetate (OPA) loaded lipid-based nanocarrier.

23. The nanocarrier of claim 22, wherein said lipid-based nanocarrier comprising at least one lipid selected from at least one phospholipid, at least one sterol, and combinations thereof.

24. The nanocarrier of claim 22 or 23, being in the form of a lipid bilayer or a liposome.

25. The nanocarrier of claim 24, wherein the nanocarrier is in the form of a uni-lamellar liposome.

26. The nanocarrier of any one of claims 22 to 25, wherein the nanocarrier is surface-associated with at least one non-active agent.

27. The nanocarrier of claim 26, wherein said non-active agent is polyethylene glycols (PEG).

28. A composition comprising a lipid-based delivery system according to any one of claims 1 to 21.

29. The composition of claim 28, being a pharmaceutical composition.

30. The composition of claim 28 or 29, configured for intravenous administration.

31. A lipid-based delivery system of any one of claims 1 to 21, for use in delivery of OPA to a patient in need thereof.

32. A lipid-based delivery system of any one of claims 1 to 21, for use in treating or delaying progression of a proliferative disorder.

33. Use of a lipid-based delivery system of any one of claims 1 to 21 in a method of treating a proliferative disorder, the method comprising administering an effective amount of the lipid-based delivery system, to a subject in need thereof.

34. The use of claim 33, wherein the proliferative disorder is cancer.

35. The use of claim 34, wherein said cancer is selected from ovary cancer, and pancreatic cancer, squamous cell cancer, lung cancer including small-cell lung cancer, non-small cell lung cancer, adenocarcinoma of the lung and squamous carcinoma of the lung, cancer of the peritoneum, hepatocellular cancer, gastric or stomach cancer including gastrointestinal cancer, pancreatic cancer, glioblastoma, cervical cancer, ovarian cancer, liver cancer, bladder cancer, hepatoma, breast cancer, colon cancer, rectal cancer, colorectal cancer, endometrial or uterine carcinoma, salivary gland carcinoma, kidney or renal cancer, prostate cancer, vulval cancer, thyroid cancer, hepatic carcinoma, anal carcinoma, penile carcinoma, and head and neck cancer.

36. The delivery system of claim 2, wherein the phospholipid is selected from phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), as well as lipid derivatives thereof, such as dimyristoylphosphatidylcholine (DMPC), dipalmitoylphosphatidylcholine (DPPC), distearoylphosphatidylcholine (DSPC), hydrogenated soy phosphatidylcholine (HSPC) and dipalmitoylphosphatidylglycerol (DPPG).

37. The delivery system of claim 2, wherein the phospholipid comprising an aliphatic chain having at least 18 carbon atoms.

38. The delivery system of claim 37, wherein the phospholipid is fully saturated, unsaturated or partially hydrogenated.

39. The delivery system according to claim 2 or 38, wherein the phospholipid is distearoylphosphatidylcholine (DSPC) or hydrogenated soy phosphatidylcholine (HSPC) or mixtures thereof.

40. The delivery system according to claim 1, in a lyophilized form.

41. A liposome comprising at least one phospholipid and OPA, wherein said at least one phospholipid is distearoylphosphatidylcholine (DSPC) or hydrogenated soy phosphatidylcholine (HSPC) or mixtures thereof.

42. The liposome according to claim 41, being surface decorated with a plurality of non-active materials.

43. The liposome according to claim 42, being surface decorated with polyethylene glycol (PEG).

44. The liposome according to any one of claims 41 to 43, comprising 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol, OPA and N-(Carbonyl-methoxypolyethyl-eneglycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE-PEG2000).

45. The liposome according to claim 44, wherein the molar ratio of is 5:3:2:0.5, or 5:3:1:0.5, 5:3:0.75:0.5, or 5:3:0.5:0.5 respectively.

46. The liposome according to any one of claims 41 to 43, comprising hydrogenated soy phosphatidylcholine (HSPC), Cholesterol, OPA and (N-(Carbonyl-methoxypolyethyl-eneglycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine) (DSPE-PEG2000).

47. The liposome according to claim 46, wherein the molar ratio is 5:3:2:0.5, or 5:3:1:0.5, 5:3:0.75:0.5, or 5:3:0.5:0.5 respectively.

48. The liposome according to claim 46 or 47, comprising hydrogenated soy phosphatidylcholine (HSPC), Cholesterol, OPA and dipalmitoylphosphatidylglycerol sodium salt (DPPG-Na).

49. The liposome according to claim 48, wherein the molar ratio is 3:2:1:1.

50. The liposome according to any one of claims 41 to 49, prepared by thin-film hydration or by ethanol injection.