GB2624638A

GB2624638A - Nano-Carriers for Drug Delivery and Methods of Preparing the Same

Info

Publication number: GB2624638A
Application number: GB2217477.5A
Authority: GB
Inventors: Abramovitch Sagi; AVIDOR Gal; Landa Benzion
Original assignee: Landa Labs 2012 Ltd
Current assignee: Landa Labs 2012 Ltd
Priority date: 2022-11-22
Filing date: 2022-11-22
Publication date: 2024-05-29
Also published as: GB202217477D0

Abstract

A pharmaceutical composition comprising nano-elements contains (a) at least one water-insoluble biodegradable compound (WIBC) having a molecular weight of more than 0.6 kDa; and b) at least one polar-carrier-insoluble active agent disposed therein; the nano-elements being dispersible in a polar carrier and having an average diameter of 200 nm or less, wherein the nano-elements contain less than 0.5 wt.% of a volatile organic compound (VOC) by weight of the nano-elements. Preferably, the WIBC is selected from (I) a group including aliphatic polyesters such as polylactic acid, and polycaprolactone; or (II) Coenzyme Q10. The polar carrier may be water. Preferably, the WIBC is plasticised by a non-volatile liquid, and a surfactant may be provided. The composition may be used in drug delivery.

Description

NANO-CARRIERS FOR DRUG DELIVERY

AND METHODS OF PREPARING THE SAME

FIELD

The present disclosure relates to compositions comprising nano-particles suitable for drug delivery. Methods of preparing these compositions are also disclosed.

BACKGROUND

Medications are taken to diagnose, prevent or treat illnesses. They exist in numerous pharmaceutical forms and can be administered to an animal or human subject by various routes. Typically, the active ingredients of such compositions, enabling their use for the diagnosis or treatment of a disease, are administered as an admixture with suitable pharmaceutically acceptable excipients which are selected according to the intended form and route of administration. Such medicaments can be introduced into the body by several routes (e.g., local or systemic including enteral and parenteral routes) each having its own advantages or disadvantages for a specific purpose and/or disease.

Nano-technology has been proven advantageous in drug development, in particular for drug formulation and delivery. The nano-particles produced by such technology, having a particle size generally between 10 nanometer (nm) and 1,000 nm, allow, among other things, site-specific and target-oriented delivery of medicines due to the ability of the nano-sized particles to, e.g., cross the blood brain barrier (BBB), enter the pulmonary system, or be absorbed through the tight junctions of endothelial cells of the skin, if small enough (e.g., having a particle size of up to 200 nm or even up to 100 nm). It has been argued that if the medicine is itself a small enough molecule having a molecular weight not exceeding about 1,000 g/mol, and being preferably smaller than 500 g/mol as known from Lipinski's "Rule of 5", it might even be capable of intracellular delivery. These nano-sized particles can be in the form of nano-spheres, nano-capsules, nano-crystals, nano-emulsions, nano-fibers, nano-tubes, polymeric micelles, polymersomes, dendrirners, liposomes, etc. Various compounds, such as polymers (biodegradable or not), are used in nano-medicine as nano-carriers of therapeutic agents, allowing the transfer of such agents into the target sites, while protecting the drug from premature degradation and/or reducing premature interaction of the drug with the biological environment. Such nano-carriers can also allow controlled or delayed release of medications at a target site. The polymers, whether homo-polymers, mixed polymers or copolymers, can either serve to form the envelop of a hollow vesicle, the drug being within the core of such polymersomes and/or intercalated in the surrounding membrane, or serve to embed the drug within the polymer matrix constituting the entire nano-carrier.

Various conventional methods for preparing these nano-carriers (e.g., polymeric) are described in the literature, mainly spontaneous formation and emulsification both suitable for hydrophobic compounds. Spontaneous formation techniques include phase separation (e.g., nano-precipitation and coacervation) and ionic gelation. The widely spread emulsification methods include oil-in-water (0/W) emulsification or W/O/W emulsification (double emulsion solvent evaporation technique), generally achievable by solvent evaporation or solvent displacement (e.g., performed by solvent diffusion or salting-out). Water-in-oil (W/O) emulsification is another technique, being suitable for hydrophilic polymers and drugs. All of these methods involve dissolving the compounds composing the nano-carriers in a suitable solvent, suitably agitating the mixture to form the particles of the desired size and separating the obtained nano-particles. Typically, residual solvents remain trapped within the nano-particles prepared by such methods.

When the solvent being used is a volatile organic compound (VOC), there is a number of drawbacks in its remaining within the nano-particles, especially considering their intended use in pharmaceuticals. Firstly, such pharmaceuticals must comply with the guidelines issued by The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), so that the amount of such residual VOCs should be limited accordingly in view of their toxicity. Secondly, such solvents, being volatile, may gradually evaporate over time, resulting in the alteration of the nano-particles' structure or properties, consequently affecting the efficacy of the drug carried thereby, such as the drug release profile.

Though the problems generated by the presence of residual VOCs are known and attempts have been made to address them, none of the solutions suggested so far seems to comprehensively resolve the challenge of their elimination. For illustration, some cumbersome methods which achieved relatively low amounts of VOCs, were limited to micro-particles (e.g., having a particle size of 2-100 micrometer (um)), whereas methods claiming to have achieved the incorporation of a drug in nano-particles often failed to load relatively large active compounds, and typically remained understandingly silent about their true VOC contents.

Despite the intensive research in the field of drug delivery via nano-carriers aimed to increase the stability of the carried drug, its loading, or its selective targeting and controlled release at a site of relevance, there remains a need for such nano-carriers. Advantageously, such carriers may display a low concentration of volatile organic solvents and pc it the delivery of water-insoluble drug molecules having a relatively high average molecular weight.

SUMMARY

Aspects of the invention relate to pharmaceutical compositions comprising a water-insoluble biodegradable compound (WIBC), such as a water-insoluble biodegradable polymer (WIBP), which can be dispersed as nano-particles or nano-droplets in a polar liquid carrier. Notably, the WIBC or WIBP molecules may have a molecular weight of 0.6 kDa or more, and the nano-particles or nano-droplets contain less than 2 wt.% of a volatile organic compound. The compositions, which typically include at least one surfactant with the WIBC, the liquid carrier, or both, further contain, in addition to the WIBCs or WIBPs, at least one active agent, such as specified herein-below. As these nano-particles or nano-droplets may serve for the delivery of the active agent, they may alternatively be referred to as nano-carriers or nano-elements. While the nano-elements are inter cilia characterized by their dispersibility in a polar liquid carrier, the nano-elements being for instance hydrophobic and the liquid aqueous, a pharmaceutical composition to be administered to a subject in need thereof, is not necessarily in liquid form. The nano-elements can be isolated from a polar liquid carrier in which they could be dispersed, so as to serve for the preparation of pharmaceutical compositions in dry forms.

These pharmaceutical compositions can be suitable for delivery by various routes, including local routes, for an effect substantially limited to the site of administration (e.g., topical, oral, rectal, etc.), and systemic routes, for a system-wide effect (i.e., enteral or parenteral, such as injection, sublingual, inhalation, transdermal etc.). Also disclosed are methods for preparing such pharmaceutical compositions.

In a first aspect of the disclosure, there is provided a pharmaceutical composition comprising nano-elements (i.e., nano-particles or nano-droplets) containing a) a water-insoluble biodegradable compound (WIBC) having a molecular weight of 0.6 kDa or more; and b) a polar-carrier-insoluble active agent; the nano-elements being dispersible in a polar carrier and having an average diameter (e.g.. Dv50) of 200 nm or less, wherein the nano-elements contain less than 2 wt.% of a volatile organic compound (VOC) by weight of the nano-elements.

In a second aspect of the disclosure, there is provided a pharmaceutical composition comprising nano-elements containing a WIBC and a polar-carrier-insoluble active agent, the WIBC being plasticized by a non-volatile liquid and having an average molecular weight of 0.6 lcDa or more, the nano-elements of plasticized WIBC including the active agent being dispersible in a polar carrier and having an average diameter (e.g., Dv50) of 200 run or less; wherein the nano-elements contain less than 2 wt.% of a VOC by weight of the nano-elements.

In some embodiments, the nano-elements of WIBC, whether plasticized or not, contain 5 less than 1.5 wt.%, or less than 1 wt.% of a VOC by weight of the nano-elements. In particular embodiments, the nano-elements contain less than 0.5 wt.%, less than 0.4 wt.%, less than 0.3 wt.%, less than 0.2 wt.%, or less than 0.1 wt.% of a VOC by weight of the nano-elements. In further particular embodiments, the nano-elements contain less than 0 09 wt.%, less than 0.08 wt.%, less than 0.07 wt.%, less than 0.06 wt.%, less than 0.05 wt.%, less than 0.04 wt.%, less 10 than 0.03 wt.%, or less than 0.02 wt.% of a VOC by weight of the nano-elements. While the nano-elements should advantageously be devoid of any VOC, amounts of up to 0.001 wt.% (which corresponds to 10 parts per million -ppm), up to 0.002 wt.% (20 ppm), up to 0.003 wt.% (30 ppm), up to 0.004 wt.% (40 ppm), up to 0.005 wt.% (50 ppm), up to 0.006 wt.% (60 ppm), up to 0.007 wt.% (70 ppm), up to 0.008 wt.% (80 ppm), up to 0.009 wt.% (90 ppm), or up to 15 0.01 wt.% (100 pm), VOC by weight of the nano-elements can be tolerated.

Though the amounts that may be present in the nano-elements are provided above in weight of an individual VOC by weight of the nano-elements, this does not preclude the presence of a blend of two or more VOCs. In such a case, the above rules should not only apply to each individual VOC of the blend but to their combined amount.

In some embodiments, the WIBC (and/or the plasticized WIBC) is characterized by at least one, at least two, or at least three of the following structural properties: i. the WIBC and/or the plasticized WIBC is insoluble in the polar carrier; ii. the WIBC and/or the plasticized WIBC has at least one of a melting temperature (Tm), a softening temperature (7's), or a glass transition temperature (Tg) of at most 300°C, at most 250°C, at most 200°C, at most 180°C, at most 150°C, or at most 120°C, said temperatures being either a first (i.e., native) Tm, Ts or Tg of the WIBC, or a second Tm, Ts or Tg of the WIBC if plasticized, or both; iii. the WIBC has a first and/or second Tm or Ts of at least 20°C, at least 30°C, at least 40°C, at least 50°C, or at least 60°C; iv. the WIBC has a first and/or second Tg of -75°C or more, -50°C or more, -25°C or more, 0°C or more, 20°C or more, 30°C or more, 40°C or more, 50°C or more, or 60°C or more; v. the WIBC has at least one of a first and/or second Tm, Ts and Tg between 20°C and 300°C, between 20°C and 250°C, between 20°C and 200°C, between 30°C and 180°C, between 40°C and 180°C, or between 50°C and 150°C; vi. the WIBC has a molecular weight of 0.7 kDa or more, 0.8 kDa or more, 0.9 kDa or more, 1 kDa or more, 2 kDa or more, or 5 kDa or more; vii. the WIBC has a molecular weight of 500 kDa or less, 300 kDa or less, 200 kDa or less, 100 kDa or less, 80 kDa or less, 50 kDa or less, 25 kDa or less, or 15 kDa or less; and viii. the WIBC has a molecular weight between 0.6 kDa and 500 kDa, between 0.7 kDa and 300 kDa, between 0.8 kDa and 200 kDa, between 1 kDa and 100 kDa, or between 2 kDa and 80 kDa.

In some embodiments, the at least one structural property fulfilled by at least one of the WIBC and the plasticized WIBC is: property i) as above listed, property ii) as above listed, property iii) as above listed, property iv) as above listed, property v) as above listed, property vi) as above listed, property vii) as above listed, or property viii) as above listed.

In some embodiments, the at least two structural properties fulfilled by at least one of the WIBC and the plasticized WIBC are: properties i) and v), properties i) and viii), or properties v) and viii), of the above-listed properties.

In some embodiments, the at least three structural properties fulfilled by at least one of the WIBC and the plasticized WIBC are: properties i), ii) and v); properties i), ii) and viii); properties i), iii) and viii); properties i), iv) and viii); properties i), v) and vi); properties i), v) and vii); or properties i), v) and viii), of the above-listed properties.

In particular embodiments, the water-insoluble biodegradable compound (WIBC) is a water-insoluble biodegradable polymer (WIBP), formed of repeating structural units, such monomers being either same (homopolymers) or different (random or block copolymers). In another particular embodiment, the polymer of the WIBP is a thermoplastic polymer. While non polymeric compounds typically have molecular weights of up to 2 kDa, generally not exceeding 1 kDa, WIBPs can be larger molecules of at least a few kDas.

As used herein, the term "nano-elements", as used with respect to the structures containing inter alia the WIBC (plasticized or not) and the polar-carrier-insoluble active agent, refers to relatively solid nano-particles or relatively liquid nano-droplets having an average diameter of 200 nm or less, 150 nm or less, 100 nm or less, 75 nm or less, or 50 nm or less, such structures being dispersed (e.g., as a result of nano-sizing) in a homogeneous medium, and forming therein a nano-suspension. Such nano-elements have typically an average diameter of 2 nm or more, 5 nm or more, 10 tun or more, 15 nm or more, or 20 urn or more. In some embodiments, the average diameter of the nano-elements of the compositions according to the present teachings is between 2 nm and 200 nm, between 5 nm and 150 nm, between 10 nm and 100 nm, between 15 nm and 75 nm, or between 20 nm and 50 nm The average diameter of the nano-elements can be determined by any suitable method and may refer to the hydrodynamic diameter of the elements as measured by Dynamic Light Scattering (DLS) and established for 50% of the nano-elements by volume (Dv50).

In view of their intended use and/or method of preparation, WIBCs suitable for the present invention are advantageously relatively solid at room temperature (circa 20°C) and up to body temperatures (e.g., circa 37°C for human subjects). Such preferences are extended to the plasticized WIBC, which further takes into account the non-volatile liquid and its relative amount, or the presence of any other material affecting the thermal behavior of the product. As can be appreciated by persons skilled in the art, as the WIBCs can be thermoplastic polymers, a "relative solidity" of such materials, or such materials being "relatively solid", at any particular temperature is referring to the fact that they are not necessarily solid but display a viscoelastic behavior. Without wishing to be bound by any particular theory, such feature of the WIBCs should ensure, to the extent necessary, that the nano-elements made therefrom are relatively non-sticky, facilitating their even distribution in a composition according to the present teachings.

In some embodiments, the first (native) viscosity of the WIBC is 107 millipascal-second (mPa-s) or less, 106 mPa-s or less, 105 mPa-s or less, 104 mPa-s or less, or 105 mPa-s or less, as measured at 50°C and a shear rate of 10 sec-1.

In other embodiments, the first (native) viscosity of the WIBC, typically a WIBP, is higher than 107 mPa-s under the aforesaid measuring conditions, being for instance of up to 1011 mPa-s, in which cases the WIBC can be combined with a non-volatile liquid, for the purpose of plasticizing the WIBC so as to reduce its viscosity and facilitate, for instance, its processing, its mixing with the active agent, and its incorporation as nano-elements into the present pharmaceutical composition. Hence, in such embodiments, the composition further contains a non-volatile liquid in an amount suitable to at least lower the first (native) viscosity of the WIBC to a second (plasticized) viscosity of no more than 107mPa-s, as measured at 50°C and a shear rate of 10 sec'.

As used herein, an active agent is deemed to be insoluble in a liquid polar carrier (referred to as a "polar-carrier-insoluble active agent" or a "carrier-insoluble active agent"), if having a solubility within the carrier it is immersed in of less than 5 wt.%, and more typically, less than 4 wt.%, less than 3 wt.%, less than 2 wt.%, less than 1 wt.%, or less than 0.5%, by weight of the polar carrier, at a temperature of 20°C.

In some embodiments, the WIBC having been plasticized by a non-volatile liquid (herein referred to as a "plasticized" WIBC) exhibits a "second" viscosity being reduced as compared to the first viscosity, the second viscosity of the WIBC being of 106 mPa-s or less, 105 mPa-s or less, 104 mPa s or less, or 103 mPa-s or less, as measured at a temperature of 50°C and a shear rate of 10 sec-1.

The pharmaceutical compositions of the present invention are in the form of a nano-suspension. Depending on the Tm or Ts of the WIBCs (either plasticized or having the desired viscosity in their native form), the composition can be at room temperature in the form of a nano-dispersion (i.e., if the Tm or Ts is above 20°C, e.g., between 25°C and 80°C), the nano-elements being relatively solid nano-particles, or alternatively be in the form of a nano-emulsion (i.e., if the Tm or Ts is below 20°C), the nano-elements being relatively liquid nano-droplets.

In some embodiments, the WIBC is plasticized and it exhibits (alone or in combination with any material added thereto as a mixture, in particular in presence of the active agents) at least one of a second Tm, Tk, or Tg, lower than the first respective Tm, Tk, or Tg of the unplasticized native WIBC, at least one of the second Tm, Ts, or Tg being 20°C or more, 30°C or more, 40°C or more, 50°C or more, or 60°C or more. In other embodiments, the at least one of a second Tm, IX, or Tg of the plasticized WIBC is at most 300°C, at most 250°C, at most 200°C, at most 190°C, at most 180°C, or at most 170°C. In some embodiments, the plasticized WIBC, and/or the mixture comprising it, has at least one of a second Tm, Ts, or Tg being in a range from 0°C to 290°C, from 10°C to 250°C, from 20°C to 200°C, from 30°C to 190°C, from 40°C to 180°C, or from 50°C to 170°C.

In some embodiments, the WIBC is a quinone, in particular ubidecarenone, also called 1,4-benzoquinone or coenzyme Q10 (CoQ10).

In other embodiments, the WIBC is a WIBP, the polymer being selected from a group of polymer families comprising: aliphatic polyesters, such as polycaprolactone (PCL), polylactic acid (PLA), poly(L-lactide) (PLLA), poly(D-lactide) (PDLA), poly(D,L-lactide) (PDLLA), polyglycolic acid (PGA), poly(p-dioxanone) (PPDO) and poly(lactic-co-glycolic acid) (PLGA); polyhydroxy-alkanoates, such as polyhydroxybutyrate (PUB), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxy-butyrate (P4HB), polyhydroxy-vaierate (PHV), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polyhydroxy-hexanoate (PHH) and polyhydroxyoctanoate (PI-10); poly(alkene dicarboxylates), such as poly(butylene succinate) (PBS), poly(butylene succinate-co-adipate) (PBSA) and poly(ethylene succinate) (PES); polycarbonates, such as poly-(trimethylene carbonate) (PTMC), poly(propylene carbonate) (PPC) and poly[oligo-(tetramethylene succinate)-co(tetramethylene carbonate); aliphatic-aromatic co-polyesters, such as poly(ethylene terephtalate) (PET) and poly(butylene adipateco-terephtalate) (PBAT); isomers thereof, copolymers thereof and combinations thereof In particular embodiments, the WIBC is CoQ10 or a WIBP being an aliphatic polyester.

In a further particular embodiment, the aliphatic polyester of the WIBP is selected from polycaprolactone, polylactic acid, isomers thereof, copolymers thereof and combinations thereof In some embodiments, the non-volatile liquid that may be added to the WIBC to lower at least one of its first (native) viscosity, Tm, Tg and Ts is selected from a group comprising: monofunctional and polyfunctional aliphatic esters, fatty esters, cyclic organic esters, fatty acids, terpenes, aromatic alcohols, aromatic ethers, aldehydes and combinations thereof. In particular embodiments, the non-volatile liquid is selected from: dibutyl adipate, Cu-Cis alkyl benzoate and dicaprylyl carbonate.

In some embodiments, the polar carrier in which the nano-elements comprising the WIBC and the carrier-insoluble active agent are dispersible (e.g., if the pharmaceutical composition is in dry form) or dispersed (e.g., if the pharmaceutical composition is in liquid form) comprise water, glycols (e.g., propylene glycol, 1,3-butanediol, 1,4-butanediol, 2-ethyl-1,3-hexanediol and 2-methyl-2-propy1-1,3-propanediol), glycerol, precursors and derivatives thereof, collectively termed herein "glycerols", (e.g., acrolein, dihydroxyacetone, glyceric acid, tartronic acid, epichlorohydrin, glycerol tertiary butyl ether, polyglycerol, glycerol ester and glycerol carbonate) and combinations thereof In a particular embodiment, the polar carrier comprises water, consists of water or is water.

In some embodiments, the pharmaceutical composition further comprises at least one surfactant, selected from an emulsifier and a hydrotrope. The surfactant(s) may be present in the nano-elements containing the WIBC (e.g., if being polar-carrier-insoluble surfactant(s)), in the liquid phase containing the polar carrier (e.g., if being polar-carrier-soluble surfactant(s)), or in both (e.g., if being intermediate emulsifiers).

In some embodiments, the at least one surfactant is an emulsifier selected from a group comprising alkyl sulfates, sulfosuccinates, alkyl benzene sulfonates, acyl methyl taurates, acyl sarcocinates, isethionates, propyl peptide condensates, monoglyceride sulfates, ether sulfonates, ester carboxylates, fatty acid salts, quaternary ammonium compounds, betaines, allcylampho-propionates, alkyliminopropionates, allcylamphoacetates, fatty alcohols, ethoxylated fatty alcohols, poly (ethylene glycol) block copolymers; ethylene oxide (E0)/propylene oxide (PO) copolymers, alkylphenol ethoxylates, alkyl glucosides and polyglucosides, fatty alkanolamides, ethoxylated alkanolamides, ethoxylated fatty acids, sorbitan derivatives, alkyl carbohydrate esters, amine oxides, ceteareths, oleths, alkyl amines, fatty esters esters, polyoxylglycerides, natural oil derivatives, ester carboxylate and urea.

In some embodiments, the at least one surfactant is a hydrotrope selected from a group comprising sodium dioctyl sulfosuccinate, urea, sodium tosylate, adenosine triphosphate, cumene sulfonate and salts (e.g., sodium, potassium, calcium, ammonium) of toluene sulfonic acid, xylene sulfonic acid and cumene sulfonic acid.

In some embodiments, the pharmaceutical composition further comprises at least one active agent within the liquid phase including the polar carrier, the active agent being soluble in the polar carrier.

An active agent is deemed to be soluble in a liquid carrier, being for instance a "polarcarrier-soluble active agent" (or a "carrier-soluble active agent"), if having a solubility within the carrier it is immersed in of 5 wt.% or more (and more typically, 6 wt.% or more, 7 wt.% or more, 8 wt.% or more, 9 wt.% or more, or 10 wt.% or more) by weight of the polar carrier, at a temperature of 20°C. As appreciated by a skilled person some materials having a sought activity can be polar-carrier-insoluble in one chemical form, and polar-carrier-soluble in another, salts of a material typically increasing its solubility.

In some embodiments, the pharmaceutical compositions comprise more than one active agent in addition to the one embedded in the WIBC nano-elements, the additional active agents being either in same or different phase. For illustration, a first additional active agent, being carrier-insoluble, is contained within the nano-elements and a second additional active agent, being carrier-soluble, can be contained within the polar carrier phase.

Advantageously, the pharmaceutical compositions of the present invention can have a) a relatively high concentration (e.g., 1 wt.% or more) of a WIBC (e.g., a WIBP) and/or of a carrier-insoluble active agent embedded therein, and/or b) the WIBC(s) and/or the active agent(s) embedded therein can have a relatively high molecular weight, as compared to conventional pharmaceutical compositions comprising such ingredients and delivering such active agents. Without wishing to be bound by theory, the relatively higher loading of the WIBC(s) in active agent(s), and/or the relatively higher potency of the nano-elements (when the efficacy also depends on the MW of the active agent(s) that may be delivered) are each expected to improve the pharmaceutic efficacy.

It is noted that nano-particles or nano-droplets of a WIBC having a particle size within the range of dimensions disclosed herein was found unexpectedly successful by the Inventors, as such forms of the WIBCs, in particular if being plasticized WIBPs, were expected to aggregate in view of their anticipated stickiness.

In a third aspect of the disclosure, there is provided a method for preparing a pharmaceutical composition comprising nano-elements consisting of a water-insoluble biodegradable compound (WIBC) and a polar-carrier-insoluble active agent, the method comprising the steps of a) providing a WIBC, wherein: i. the WIBC has a molecular weight of at least 0.6 kDa; ii. the WIBC has at least one of a first Tm, Ts, or Tg of 300°C or less; and iii. the WIBC has a first viscosity optionally higher than 107 mPa-s, as measured at 50°C and a shear rate of 10 sec-I; b) providing a polar-carrier-insoluble active agent; c) mixing the WIBC and the polar-carrier-insoluble active agent with a non-volatile liquid miscible therewith, and optionally with at least one surfactant, the mixing being at a mixing temperature equal to or higher than the at least one first Tm, Ts, or Tg of the WIBC, whereby a homogeneous mixture including the plasticized WIBC and polar-insoluble active agent is formed, the plasticized WIBC having a second Tm, Ts, or Tg lower than the respective first Tm, Ts, or Tg, and a second viscosity lower than the first viscosity, the second viscosity being of 107 mPa.s or less, as measured at 50°C and a shear rate of 10 se&; d) combining the plasticized WIBC and polar-carrier-insoluble active agent mixture (optionally containing at least one surfactant) with a polar carrier; and e) nano-sizing the combination of step d) by applying shear at a shearing temperature equal to or higher than at least one of the second Tm, Ts, or Tg of the plasticized WIBC, so as to obtain a nano-suspension, whereby nano-elements comprising the plasticized WIBC and the polar-carrier-insoluble active agent are dispersed in the polar carrier, the nano-elements being characterized by: i) having an average diameter (e.g., Dv50) of 200 nm or less; and ii) containing less than 2 wt.% of a volatile organic compound (VOC) by weight of the nano-elements.

In some embodiments of the third aspect, the mixing temperature in step c) is higher than the at least one first Tm, Ts, or Tg of the WIBC by 5°C or more, 10°C or more, 20°C or more, 30°C or more, or 40°C or more, as long as the mixing is performed at a temperature at which an insignificant part of the non-volatile liquid is boiled away. Assuming that the non-volatile liquid has a boiling temperature Tbr at the pressure of the mixing step, then in some embodiments the mixing temperature can additionally be lower than the boiling temperature Tbr of the non-volatile liquid. When the duration of mixing is sufficiently brief and/or the nonvolatile liquid in sufficient excess, the mixing temperature can alternatively be at boiling temperature Tbi or above.

In a fourth aspect of the disclosure, there is provided a method for preparing a pharmaceutical composition comprising nano-elements consisting of a WIBC and a polarcarrier-insoluble active agent, the method comprising the steps of: a) providing a WIBC, wherein: i. the WIBC has a molecular weight of at least 0.6 kDa; ii. the WIBC has at least one of a first Tin, Ts, or Tg of 300°C or less; and iii. the WIBC has a first viscosity of 107 mPa's or less, as measured at 50°C and a shear rate of 10 sec-I; b) providing a polar-carrier-insoluble active agent and mixing it with the WIBC; c) combining the WIBC and the polar-carrier-insoluble active agent mixture with a polar carrier, and optionally with at least one surfactant; and d) nano-sizing the combination of step c) by applying shear at a shearing temperature equal to or higher than the at least one first Tm, Ts, or Tg of the WIBC, so as to obtain a nano-suspension, whereby nano-elements comprising the WIBC and the polar-carrier-insoluble active agent are dispersed in the polar carrier, the nano-elements being characterized by: i) having an average diameter (e.g., Dv50) of 200 nm or less; and ii) containing less than 2 wt.% of a VOC by weight of the nano-elements.

In some embodiments of each of the third and fourth aspects, the shearing temperature is higher than the second Tin, Ts, or Tg of the plasticized WIBC (or higher than the first Tin, Ts, or Tg, in case of an un-plasticized WIBC) by 5°C or more, 10°C or more, 20°C or more, 30°C or more, or 40°C or more, as long as the nano-sizing is performed at a temperature at which an insignificant part of the polar carrier is boiled away. Assuming that the polar carrier has a boiling temperature Tbe at the pressure of the nano-sizing step, then in some embodiments, the shearing temperature can additionally be lower than the boiling point Tbi of the non-volatile liquid (if added) and/or lower than the boiling point Tb, of the polar carrier, under the pressure at which the nano-sizing step is performed, by 5°C or more, 10°C or more, 20°C or more, 30°C or more, or 40°C or more. When the duration of nano-sizing is sufficiently brief and/or the polar carrier in sufficient excess, the nano-sizing temperature can alternatively be at boiling temperature Tbe or above.

In some embodiments of each of the third and fourth aspects, the obtained nano-suspension is a nano-emulsion, and the method comprises an additional step, wherein the obtained nano-emulsion is cooled to a temperature lower than at least one of the first or second Tm, Ts, or Tg of the WIBC. While such cooling may passively occur upon termination of nano-sizing, the temperature of the nano-suspension naturally decreasing over time to room temperature, in some embodiments, the cooling is performed by actively lowering the temperature of the nano-emulsion by any suitable cooling method. Additionally, or alternatively, the cooling is performed under continued shearing or any other method maintaining the agitation of the composition. While the composition may remain a nano-emulsion following its active or passive cooling, in some embodiments, the composition can then be a nano-dispersion.

In some embodiments of each of the third and fourth aspects, the polar-carrier-insoluble active agent (or each such agent, if more than one) can be combined with the WIBC(s) either a) prior to heating the WIBC(s) and/or mixing with optional non-volatile liquid(s), surfactant(s) and/or any other desirable ingredient, or b) after any such heating and/or mixing, once the WIBC(s) are at least partially softened or plasticized by heat and/or ingredients mixed therewith.

In some embodiments of each of the third and fourth aspects, the method further comprises dissolving at least one polar-carrier-soluble active agent within the polar carrier. The dissolution of such active agents can be performed at various steps during the preparation of the composition, depending on the resistance of the active agent to temperatures, mixing or shearing conditions applied at the envisioned step. Relatively resistant active agents can be added i) whilst combining the WIBC (or the plasticized WIBC) with the polar carrier; or ii) whilst nano-sizing the compositions components so as to obtain the nano-elements including the WIBC and carrier-insoluble active agent(s). Alternatively, the active agent(s) which are soluble in the polar carrier, in particular if shear-sensitive, can be dissolved in the obtained nano-suspension, agents being relatively heat-sensitive being preferably dissolved in the polar carrier of the nano-emulsion or nano-dispersion after cooling.

In some embodiments, the nano-elements obtained by the afore-said methods relying on incorporation of active agents within a WIBC, plasticized or not, have a wt.% content of a VOC by weight of the nano-elements as detailed for the pharmaceutical compositions. In particular embodiments, the nano-elements obtained by the present methods contain between 0.001 wt.% and 0.5 wt.%, between 0.002 wt.% and 0.4 wt.%, between 0.003 wt.% and 0.3 wt.%, between 0.004 wt.% and 0.2 wt.%, between 0.005 wt.% and 0.1 wt.%, between 0.001 wt.% and 0.09 wt.%, between 0.002 wt.% and 0.08 wt.%, between 0.003 wt.% and 0.07 wt.%, between 0.004 wt.% and 0.06 wt.%, or between 0.005 wt.% and 0.05 wt.% of a VOC (or of a blend of VOCs) by weight of the nano-elements.

In some embodiments of each of the third and fourth aspects, the WIBC, the carrier-insoluble active agent, the polar carrier, and if desired for the preparation of the pharmaceutical composition, the non-volatile liquid, the surfactant, and the carrier-soluble active agent, are substantially as described above and herein detailed.

It is noted in this context that while compounds have been for simplicity categorized according to their main role in the present invention, in particular with respect to the preparation methods, such functions are not exclusive one of the other. For illustration, a non-volatile liquid typically serving to plasticize the WIBC may also serve as a surfactant for the nano-elements, and vice versa a surfactant may lower the characterizing temperatures of the WIBC (e.g., soften it or plasticize it). The predominance of one role over the other may depend upon a material inherent potency in the respective fields, but also on the relative presence of the material in the composition. For instance, a material deemed a carrier if constituting a significant enough part (e.g., more than 20 wt.%) of the liquid phase, may be considered to fulfil a distinct function if in a relatively lower amount, such amount being more adapted to its secondary roles.

In some embodiments of each of the third and fourth aspects, the method further comprises replacing the polar carrier that served during the nano-sizing step by any other liquid vehicle adapted to a liquid dosage form of the composition. In other embodiments, the method further comprises isolating the nano-elements out of the polar carrier. The isolated nano-elements may be further rinsed, dried or subjected to any other treatment rendering them suitable for the preparation of a dry dosage form of the composition.

In some embodiments, the pharmaceutical compositions of the present invention (whether 5 in liquid or dry form) include nano-elements that can be prepared according to the methods herein disclosed and may further contain any additive conventionally present in such compositions.

In a fifth aspect of the disclosure, there are provided uses for the present pharmaceutical compositions, for the diagnostic, prevention or treatment of any ailment according to the active agent(s) incorporated in the nano-elements according to the present teachings. As the active agents can be selected from a group comprising analgesics, anti-inflammatory agents, anti-addiction agents, anti-bacterials, anticonvulsants, antidementia agents, antidepressants, antiemetics, anesthetics, antifungals, antigout agents, antimigraine agents, antimyasthenic agents, antimycobacterials, antineoplastics, anti-obesity agents, antiparasitics, antiparkinson agents, antipsychotics, antispasticity agents, antivirals, anxiolytics, bipolar agents, blood glucose regulators, blood products, cardiovascular agents, central nervous system agents, contraceptives, dental and oral agents, dermatological agents, electrolytes, minerals, metals, vitamins, gastrointestinal agents, genitourinary agents, hormonal agents (adrenal), hormonal agents (pituitary), hormonal agents (prostaglandins), hormonal agents (sex hormones), hormonal agents (thyroid), hormone suppressant (adrenal), hormone suppressant (pituitary), hormone suppressant (thyroid), immunological agents, infertility agents, inflammatory bowel disease agents, metabolic bone disease agents, ophthalmic agents, otic agents, respiratory tract agents, sexual disorder agents, skeletal muscle relaxants and sleep disorder agents, the present compositions can accordingly be used to treat pain, inflammatory diseases, addictions, bacterial infections, and so on. Such uses of the pharmaceutical compositions are generally, but not necessarily, intended for a mammalian subject (e.g., a human person), and in accordance with the active agents being present in the nano-elements.

While for brevity the present compositions are being described as suitable for the diagnostic and treatment of animal subjects, as relevant for veterinary or human use, they might also serve for the delivery or controlled release of agents of relevance to the plant realm, such as fungicides, insecticides, herbicides, phytohormones or other fertilizers. All such agents, uses and subjects are encompassed, so that the term pharmaceutical composition is to be interpreted in an accordingly broad sense.

Additional objects, features and advantages of the disclosure will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from the description or recognized by practicing the disclosure as described in the written description and claims hereof, as well as the appended drawings. Various features and sub-combinations of embodiments of the disclosure may be employed without reference to other features and sub-combinations.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments of the disclosure will now be described further, by way of example, with reference to the accompanying figures, where like reference numerals or characters indicate corresponding or like components. The description, together with the figures, makes apparent to a person having ordinary skill in the art how some embodiments of the disclosure may be practiced. The figures are for the purpose of illustrative discussion and no attempt is made to show structural details of an embodiment in more detail than is necessary for a fundamental understanding of the disclosure. For the sake of clarity and convenience of presentation, some objects depicted in the figures are not necessarily shown to scale.

In the Figures: Figure 1 depicts a simplified schematic diagram of a method for preparing nano-elements suitable for a pharmaceutical composition according to an embodiment of the present teachings; Figure 2 shows the particle size distribution (PSD) of nano-particles of PCL in a nano-20 dispersion, as measured by DLS and presented per volume, the nano-particles being prepared according to the present method safe for the inclusion of a polar-carrier-insoluble active ingredient; and Figure 3 is a CryoTEM image of the nano-particles of PCL, the PSD of which was previously shown in Figure 2.

DETAILED DESCRIPTION

The present invention relates to pharmaceutical compositions comprising nano-elements, e.g., nano-particles or nano-droplets, containing a water-insoluble biodegradable compound or WIBC (in particular, a water-insoluble, biodegradable polymer or WIBP) and a polar-carrierinsoluble active agent miscible therewith, the nano-elements being dispersible or dispersed as a nano-suspension in a polar carrier. Advantageously, the WIBC may have a molecular weight of 0.6 IcDa or more and can be, if desired, plasticized by a non-volatile liquid, which can also be referred to as a plasticizing agent. The nano-elements are characterized by a low contents of volatile organic compounds (VOC(s)), such volatile compounds being present in an amount of less than 2 wt.% of VOC by weight of the nano-elements. The nano-elements comprising the optionally plasticized WIBC and the polar-carrier-insoluble active agent may further include a surfactant to enable or increase the dispersibility of the nano-elements in the composition.

Alternatively, or additionally, surfactant(s) or active agent(s) can be present in the polar carrier, if soluble therein. Methods for preparing such pharmaceutical compositions and uses thereof are also disclosed.

Before explaining at least one embodiment in detail, it is to be understood that the disclosure is not necessarily limited in its application to the details of construction and the arrangement of the components and/or methods set forth herein. The disclosure is capable of other embodiments or of being practiced or carried out in various ways. The phraseology and terminology employed herein are for descriptive purpose and should not be regarded as limiting.

It is to be understood that both the foregoing general description and the following detailed description, including the materials, methods and examples, are merely exemplary of the disclosure, and are intended to provide an overview or framework to understanding the nature and character of the invention as it is claimed, and are not intended to be necessarily limiting.

As used herein, and in the context of the compositions described in the present teachings, the term "pharmaceutical composition" relates to a composition comprising at least one pharmaceutical agent within nano-elements consisting of one or more WIBCs, the composition being adapted for administration to a living subject, or samples thereof, the living subjects being animals (e.g., humans) or plants. A pharmaceutical agent may include a drug intended for use in the diagnosis, cure, mitigation, treatment, therapy, or prevention of disease, and further includes nutraceuticals, vitamins or food supplements.

Biodegradability The water-insoluble biodegradable compounds (WIBCs) used in the present invention can be broken down by any suitable mechanism of biodegradation adapted to their structure and chemical identity. Upon the delivery of nano-elements in which they provide a matrix for an active agent to be carried thereby to a living subject, the WIBCs can be degraded by biological mechanisms. Suitable WIBCs are typically biocompatible with the physiological environment in which they are to biodegrade, such as found following their delivery in the form of nano-elements. Suitable WIBCs can also be termed bioresorbable or bioabsorbable in the general literature, depending on their in vivo fate and prospective elimination from the body, but for simplicity all such compounds will be generally referred to herein as "biodegradable". A WIBC is said to be biodegradable if breaking down relatively rapidly after fulfilling its purpose (e.g., by a bacterial decomposition process in the environment or by an in vivo enzymatic or metabolic process) to result in natural by-products. Biodegradable WIBCs are known, and new ones are being developed. Their relative biodegradability in various environments can be assessed by a number of methods, which depending on the conditions of interest can be procedures based on or modified from standards such as ASTM F1635.

Despite its propensity to naturally decompose under suitable physiological conditions, a biodegradable WIBC adapted to the present invention should be stable and durable enough for its intended use during storage and application, which can be particularly challenging if this use involves conditions that would enhance biodegradability. For example, compositions containing the WIBCs, formulated as a tablet and administered orally, are expected to endure the passage through the digestive system, and avoid the degradation of the WIBC before it is able to reach their target, hence, the selection of suitable WIBCs for the pharmaceutical compositions of the present invention should take these factors into consideration.

Insolubility Besides their biodegradability, the WIBCs are preferably substantially non-soluble in the liquid phase of the composition including the polar carrier (e.g., water), in which they are dispersible as nano-elements during their preparation. For similar reasons, they should be substantially insoluble in the liquid vehicle of a liquid dosage form (whether same or different than the polar carrier used during their preparation).

As used herein, the solubility of a material (e.g., a WIBC, a non-volatile liquid, or an active agent) refers to the amount of such component that can be introduced into the liquid (e.g., polar) carrier, while maintaining the clarity of the liquid medium. The solubilities of specific components of the composition within any particular liquid are typically assessed in the sole polar carrier in absence of any other possible components of the compositions but may be alternatively determined with respect to the final composition of the liquid phase including the carrier or with respect to the final composition of the liquid vehicle of a liquid dosage form.

WIBCs (or any other material of interest for the present invention) are deemed insoluble if their solubility in the polar carrier, or in the liquid phase containing it, or in the liquid vehicle of a dosage form, is 5 wt.% or less, 4 wt.% or less, 3 wt.% or less, 2 wt.% or less, 1 wt.% or less, 0.5 wt.% or less, or 0.1 wt.% or less by weight of the fluid being considered. For illustration, no more than 5 g of a material that is non-soluble in a polar carrier would dissolve in 100 g of the carrier. This substantial insolubility, while typically measured at room temperature, should preferably apply at any temperature at which these ingredients are combined and processed, i.e., even at relatively elevated temperatures, the solubility of these compounds in the polar carrier should remain within the required ranges. A material satisfying these conditions can be referred to as a "polar-carrier-insoluble" material.

Such insolubility of the material is expected to prevent leaching out into their surrounding media of one or more of the WIBC and of the carrier-insoluble active agents (or of any other one of the constituents of the nano-elements). Such leaching out, were the material soluble in the polar carrier, may affect the relative proportions of the constituents of the nano-elements, their size, or any other such parameter that may ultimately adversely affect the efficacy of the composition. Considering for illustration an active agent initially embedded in the nano-particles of WIBCs, if such agents were to leak out in an uncontrolled manner as a result of inappropriate solubility, such agents could be discharged from the nano-carriers in an untimely manner and/or possibly at an inadequate localization with respect to a desired target area.

Regardless of the composition of the polar liquid phase including the polar carrier in which the WIBC and carrier-insoluble active agent are to be dispersed as nano-elements, the WIBC can first be characterized as being water-insoluble (i.e., having a solubility of less than wt.% in water as typically established at room temperature).

Molecular weight WIBCs suitable for the present compositions, methods, and uses can have a molecular weight (MW) of 0.6 kDa or more, 0.7 kDa or more, 0.8 kDa or more, 0.9 kDa or more, 1 kDa or more, WIBPs also displaying MW of 2 kDa or more, 5 kDa or more, or 10 kDa or more. Typically, their molecular weight does not exceed 2 kDa if the compound is not a polymer, WIBPs reaching MWs of up to 500 kDa, and being generally of 300 kDa or less, 200 kDa or less, 100 kDa or less, 80 kDa or less, 50 kDa or less, 25 kDa or less, or of 15 kDa or less. In another embodiment, the molecular weight of the WIBCs is between 0.6 kDa and 500 kDa, between 0.7 kDa and 300 kDa, between 0.8 kDa and 200 kDa, between 1 kDa and 100 kDa, or between 2 kDa and 80 kDa.

As used herein, the term "molecular weight" (or "MW") refers either to the actual molecular weight as can be calculated for a non-polymeric WIBC or for any other compound having a known molecular structure, which can also be expressed in grams/mole, or to the weight average MW of WIBPs, which may be a blend of polymers each containing a slightly different number of repeating units, weight average MW of polymers being typically expressed in Daltons.

The molecular weight of the WIBCs can be provided by their suppliers and can be independently determined by standard methods including for instance gel permeation chromatography, high pressure liquid chromatography (HPLC), size-exclusion chromatography, light scattering or matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy MALDI-TOF MS, some of these methods are described in ASTM D4001 or ISO 16014-3.

Characterizing temperatures While the vast majority of non-polymeric compounds can be characterized by a melting temperature at which they change from a solid phase to a liquid one, polymeric compounds can additionally or alternatively be defined by a glass transition temperature if amorphous, pure amorphous polymers lacking a Tm. Pure crystalline polymers can be characterized by their Tm, semi-crystalline polymers often displaying two characterizing temperatures (e.g., Tg and Tm) reflecting the respective proportion of amorphous and crystalline parts in the molecule. Such polymers may also be defined by their softening temperature Ts midway the log step to melting. As the glass transition temperature describes the transition of a glass state into a rubbery state, and the softening temperature an intermediate inflection in the thermal analysis of a material, they typically relate to a range of temperatures or one at which the process will first be observed.

Therefore, depending on the chemical nature of the WIBC, the temperature that may characterize its thermal behavior can be at least one of a melting temperature (Tm), a softening temperature (Ts) and a glass transition temperature (Tg). Hence, when a WIBC is defined as suitably having at least one of a first and/or second Tm, Ts and Tg within a particular range, the temperature considered is as relevant to the material. Some compounds may be identified by two such characterizing temperatures, in which case performing a method step at a temperature above any of the two temperatures could be above the lowest of the two (which would prolong the step) or the highest of the two (which would accelerate the step). Conversely, performing a method step at a temperature below any of the two temperatures could be below the highest of the two or the lowest of the two. Taking for illustration a semi-crystalline polymer that can be characterized by all three temperatures, Tm, Ts, and Tg in order of decreasing values, heating above Tg (i.e., above at least one), might be insufficient to reach Ts or Tm, while heating above Ts (i.e., above at least two), might be insufficient to reach Tm. Only heating above Tm would ensure that the temperature of heating is higher than all three temperatures that may characterize such exemplary polymer.

In some embodiments, the WIBCs suitable for the present compositions are characterized by at least one of a melting temperature (Tm), softening temperature (Ts) or glass transition temperature (Tg) being of at least 20°C, at least 30°C, at least 40°C, at least 50°C, or at least 60°C. In other embodiments, at least one of the Tm, Ts and Tg of the WIBCs is at most 300°C, at most 250°C, at most 200°C, at most 180°C, at most 150°C, or at most 120°C. In some embodiments, at least one of the Tm, Ts and Tg of the WIBCs is between 20°C and 300°C, between 20°C and 250°C, between 20°C and 200°C, between 30°C and 180°C, between 40°C and 150°C, or between 50°C and 120°C. Such thermal characteristics of a WIBC can be provided by its manufacturer or independently determined by standard methods, for instance, thermal analysis methods, e.g., Differential Scanning Calorimetry (DSC), such as described in ASTM 3418, ISO 3146, ASTM D1525, ISO 11357-3, or ASTM E1356. The characterizing temperatures (Tm, Ts or Tg) of a WIBC may be referred to as a "first" Tm, Ts or Tg, when relating to the native / unmodified compound, and may be referred to as a "second" Tm, Ts or Tg, when relating to the WIBC as modified, e.g., by its mixing with a non-volatile liquid yielding a plasticized WIBC.

Polymeric and non-polymeric WIBCs In some embodiments, the water-insoluble biodegradable compounds (WIBCs) used in the present compositions, methods and uses are water-insoluble biodegradable polymers (WIBPs), such polymers also including their fragmented / shorter versions known oligomers.

As the WIBPs are desirably adapted for biodegradation once delivered into the physiological environment of the living subject, such polymers generally contain hydrolysable functional groups.

Suitable WIBPs, which can be of natural or synthetic origin, are thermoplastic in nature, their shapes being capable of reversible modifications upon suitable heating and cooling.

Appropriate WIBPs can also be plasticized with a suitable non-volatile liquid, such optional treatment of the WIBPs facilitating their nano-sizing to an extent expediting the delivery of the nano-elements and the active agents contained therein.

Synthetic WIBPs can be selected from aliphatic polyesters, polyhydroxy-alkanoates, poly(alkene dicarboxylates), polycarbonates, aliphatic-aromatic co-polyesters, enantiomers thereof, copolymers thereof and combinations thereof.

To the extent that the monomers forming the WIBPs have chiral centers, all enantiomers and stereoisomers are encompassed. For illustration, lactic acid (2-hydroxypropionic acid, LA), exists as two enantiomers, L-and D-lactic acid, so that PLA has stereoisomers, such as poly(Llactide) (PLLA), poly(D-lactide) (PDLA), and poly(DL-lactide) (PDLLA). A WIBP may therefore be a mixture of isomers of a same molecule or a specific stereoisomer (or a stereo copolymer).

In some embodiments, the WIBP is selected from a group comprising: aliphatic polyesters, such as poly-caprolactone (PCL), polylactic acid (PLA), poly(L-lactide) (PLLA), poly(D-lactide) (PDLA), poly(D,L-lactide) (PDLLA), polyglycolic acid (PGA), poly(lactic-coglycolic acid) (PLGA), and poly(p-dioxanone) (PPD0); polyhydroxy-alkanoates (PHA), including polyhydroxybutyrate (PHB) (such as poly-3-hydroxy-butyrate (P3HB), poly-4- hydroxy-butyrate (P4HB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), and polyhydroxyoctanoate (PHO); poly(alkene dicarboxylates), such as poly(butylene succinate) (PBS), poly(butylene succinateco-adipate) (PBSA) and poly(ethylene succinate) (PES); polycarbonates, such as poly(trimethylene carbonate) (PTMC), poly(propylene carbonate) (PPC) and poly- [oligo(tetramethylene succinate)-co(tetramethylene carbonate); aliphatic-aromatic co-polyesters, such as poly(ethylene terephtalate) (PET) and poly(butylene adipate-coterephtalate) (PBAT); their isomers, copolymers and combinations thereof.

In a particular embodiment, the WIBP is or includes an aliphatic polyester, isomers, copolymers and combinations thereof In a further particular embodiment, the WIBP is PCL. In 25 another further particular embodiment, the WIBP is PLA.

Such polymers may be identified according to their respective characteristic functional groups as detectable by standard methods known to the skilled persons, for instance, by Fourier-transform infrared (FTIR) spectroscopy.

Non-polymeric WIBCs suitable for the compositions, methods and uses of the present 30 invention include quinones. In a particular embodiment, the non-polymeric WIBC is coenzyme Q10 (CoQ10).

Additionally, a WIBC, can be a blend of different compounds, whether polymeric or not, the properties of the mixture (e.g., a characterizing temperature, a viscosity, etc.) satisfying the ranges set for a suitable individual compound. For instance, a WIBC or WIBP having a Tm, Ts or Tg out of a range previously deemed suitable (e.g., being lower than 20°C or higher than 300°C) may be combined with a WIBC or WIBP having a Tm, ix, or Tg adapted to "correct" the characterizing temperature of the obtained mixture to be suitable for the purpose of the present invention. For illustration, a WIBC can be a blend of polymers or a copolymer including at least one of the aforementioned WIBPs, such copolymers may contribute to the biocompatibility, biodegradability and mechanical and optical properties of the nano-elements.

Viscosity WIBCs can alternatively (or additionally) be selected for their viscosity to be adapted to their shearing in the present methods for preparing the nano-elements to be part of the pharmaceutical compositions. WIBCs suitable for the present methods, compositions and uses can typically have a viscosity which does not exceed of 1011 millipascal-second (mPa-s, being equivalent to a centipoise), and which is often of 5x1010mPa s or less, 1016 mPa-s or less, 5x109 mPa-s or less, 109 mPa-s or less, 5x108 mPa-s or less, 108 mPa-s or less, 5x107 mPa-s or less, 107 mPa-s or less, or of 5x106mPa-s or less, as determined at a temperature of 50°C and a shear rate of 10 sec-1.

For efficient shearing to take place, the viscosity of the WIBCs should preferably be of 107 mPa-s or less at a temperature of 50°C and a shear rate of 10 sec-1. Such viscosity can relate to the native property of the isolated unmodified WIBC, in which case it can be referred to as a "first viscosity", or it may refer to the viscosity of the WIBC as modified by its mixing with materials miscible therewith, in which case it can be referred to as the "second viscosity" of the WIBC. For illustration, the second viscosity can be of a WIBP plasticized with a suitable non-volatile liquid. The viscosity of a material (whether modified or not by the presence of others) at any temperature of interest (or in a range thereof) can be determined by routine thermorheological analysis, such as described in ASTM D3835 or ASTM D440.

While a non-volatile liquid can be added to the WIBC or WIBP regardless of their native viscosity, such materials are typically used in the present compositions or methods when the WIBC has a relatively high first viscosity, such as higher than 107 mPa-s, at 50°C and a shear rate of 10 sec1. The non-volatile liquid (which may also be referred to as a plasticizing liquid) is contained in the nano-elements including the plasticized WIBC, the liquid being typically adsorbed or otherwise retained by the WIBC.

Such "plasticizing" typically results in weight gain and/or a volume gain relative to the WIBC own mass or volume in its native form. Such plasticizing of the WIBC renders the plasticized WIBC softer and more malleable, as demonstrated by its reduced viscosity (Le., the second viscosity being smaller than the first), facilitating their later nano-sizing to an extent expediting the delivery of the resulting nano-elements and active agents contained therein from the pharmaceutical compositions to the leaving subject treated thereby.

Advantageously, the reduced viscosity should be adapted to the shearing process (e.g., shearing equipment, shearing temperature, etc.) being elected to nano-size the plasticized WIBC (e.g., a plasticized WIBP). For instance, the non-volatile liquid and its proportion relative to the WIBC can be selected to lower the viscosity of the WIBC by at least half-a-log, or at least one log, and so on, as might be required. For illustration, if the WIBC has a first viscosity of 108 mPa-s, a plasticizing agent and its amount would enable a reduction of half-a-log if the WIBC so plasticized has a second viscosity of 5x107 mPa-s, or (if in a higher amount or if alternatively selected to be a more potent agent) would enable a reduction of one log if the WIBC so plasticized has a second viscosity of 107 rnPa-s, as measured at a temperature of 50°C and a shear rate of 10 sec* In some embodiments, the second viscosity of a WIBC plasticized with the non-volatile liquid is between 102 mPa-s and 107 mPa-s, between 5x107 mPa-s and 106 mPa-s, between 5x102 mPa-s and 105 mPa s, between 103 mPa-s and 5x104 mPa.-s, or between 103 mPa-s and 104 mPa-s, as measured at 50°C and at a shear rate of 10 sec-1. Viscosity can be measured with any suitable rheometer equipped with a spindle adapted to the intended range of viscosities at the appropriate shear rate.

Plasticization While mentioned above for their effects on the viscosity of the WIBCs, to the extent reducing it would be desired, the non-volatile liquids that may be incorporated with the WIBC in the nano-elements may fulfil additional functions. Plasticizing, in particular of WIBPs, can be visually observed, as the polymer appears to be swollen at a temperature below melting. At higher temperatures, the effect of the non-volatile liquid can be detected via its plasticizing activity, which includes its ability to lower at least one of the temperatures characterizing the native WIBCs.

Decreasing a characterizing temperature of the WIBC, allows accordingly lowering processing temperatures at which the nano-elements of the pharmaceutical compositions can be prepared. For illustration, while the WIBC can have a first (native) Tm, Ts or Tg of 200°C or less in absence of a suitable non-volatile liquid, the addition of such plasticizing agents may yield a plasticized WIBC having a second (modified) Tm, Ts or Tg, lower than the first, the second temperature being for instance of 95°C or less. The drop in temperature afforded by the presence of the non-volatile liquid need not be as dramatic as illustrated, obviously depending on the value of the first Tm, Ts or Tg of the native WIBC, on the second Tm, Ts or Tg as may be desired to facilitate the preparation of the nano-elements and/or their later delivery, preferably on the boiling temperatures (Tb) of liquids which are to remain present in the composition (but not necessarily if the steps are brief enough and/or the liquids in excess in case some are boiled away), and/or on the concentration of the plasticizing agent with respect to the compound being plasticized.

If the mixture of WIBC(s), the carrier-insoluble active agent(s) and non-volatile liquid(s) further comprises ingredients (e.g., rheological modifiers, surfactants, preservatives, or any like material which may have a plasticizing effect) that may impact the softening property of the resulting combination due to form, or be within, the nano-elements, then additionally and alternatively, the thermal characteristics deemed suitable for the present invention would apply to the entire mixture.

Hence, in some embodiments, the plasticized WIBC, or a mixture of components including it, has at least one of a Tm, Ts and Tg being in a range of 0°C to 290°C, 10°C to 250°C, 20°C to 200°C, 30°C to 180°C, 40°C to 150°C, or 50°C to 120°C. Such thermal behavior and characterizing temperatures can be assessed while preparing the plasticized WIBC or mixtures including the same, or upon completion of the preparation method of the composition.

Non-volatile plasticizing liquids While the role that the presence of non-volatile liquids may have in the efficacy of the nano-elements including the WIBC delivering the carrier-insoluble active agent is not ignored, the selection of such materials is mainly considered with a view of improving the processability of the W1BP, so as to facilitate the preparation and dispersion of the nano-elements within the polar carrier phase from which they might be later isolated (e.g., to transfer them to a different liquid vehicle adapted to a particular liquid dosage form or to prepare a dry dosage form).

Particularly suitable non-volatile liquids can both lower the viscosity of the WIBC and lower at least one of its Tm, Ts and Tg, as previously separately discussed. Advantageously, suitable non-volatile liquids improve the processability of the WIBC under conditions suitable for its shearing into nano-particles, the shearing temperature causing initially the formation of nano-droplets.

First, as implied by their names, agents adapted to plasticize a WIBC according to the present teachings are liquid at the temperature at which the WIBC is to be processed, namely 5 at least at one of the temperatures of mixing with the WIBC and of shearing. Such liquid agents can also be liquid at room temperature.

To ensure that their effect would perdure, the plasticizing liquids are preferably nonvolatile. As used herein, the term "non-volatile", as can be used with regards to a liquid that may plasticize the WIBC, refers to liquids exhibiting a low vapor pressure, such as less than 40 Pascal (Newton per square meter) at a temperature of about 20°C. Such vapor pressure values are typically provided by the manufacturer of the liquid, but can be independently determined by standard methods, such as described in ASTM D2879, E1194, or E1782 according to the range of the vapor pressure. The low or substantially null volatility of the non-volatile liquids that may be used to plasticize a WIBC, if so desired, should be maintained at the highest temperature at which the plasticized WIBC is processed. The use of such non-volatile liquids allows the WIBCs to remain in their plasticized state, without the risk of evaporation or elimination of the liquids, even at high temperatures of preparing the nano-elements for the pharmaceutical compositions according to the present methods.

Suitable non-volatile liquids are also characterized by having a boiling point that is higher than room temperature, higher than body temperature, and higher than an elevated temperature as may be desired for the preparation of the composition, as it is preferred that the liquids selected for plasticizing the WIBCs of the present invention do not substantially evaporate during or after the preparation of the pharmaceutical compositions. That having been said, some boiling away may be tolerated if the mixing step at which the non-volatile liquids plasticize the WIBC is brief enough to ensure a residual presence as desired, and/or if the non-volatile liquids are added in sufficient excess to compensate for any partial boiling away that may take place.

For similar reasons of being desirably maintained with the WIBC to be plasticized therewith, and retained in the nano-elements comprising it, the non-polar liquid should preferably be unable to migrate to the polar carrier phase. Hence, suitable non-volatile liquids are essentially not miscible in such polar carriers (e g., water), their solubility in the pure polar carrier or in the liquid phase containing it being as previously detailed for the WIBC, namely being of 5 wt.% or less, 4 wt.% or less, 3 wt.% or less, 2 wt.% or less, 1 wt.% or less, of 0.5 wt.% or less, or of 0.1 wt.% or less by weight of the carrier or the phase containing it.

Such non-volatile liquids need to be compatible with the WIBC of the composition (i.e., able to plasticize it: e.g., decreasing its Tm, Ts or Tg, and/or decreasing its viscosity). A nonvolatile liquid adapted for a particular WIBC can be selected accordingly by routine experimentation. For instance, given a particular WIBC, various non-volatile liquids can be mixed with it, at one or more relative concentrations, and their effects on the WIBC being plasticized monitored by thermo-rheology (for their ability to decrease viscosity as a function of temperature) and by thermal analysis (e.g., by DSC, for their ability to decrease the Tm, Ts or Tg of the native WIBC). The non-volatile liquids most potent with respect to the particular WIBC can be selected accordingly.

Fundamentally, a material or a chemical composition is compatible with another if it does not prevent its activity or does not reduce it to an extent that would significantly affect the intended purpose. Such compatibility may be from a chemical standpoint, for instance, sharing similar functional chemical groups or each material having respective moieties that may desirably interact with one another. This kind of compatibility can be demonstrated by the combined materials forming a homogeneous mixture, rather than separate into different phases. Materials should also be compatible with the methods used for the preparation of the composition, not being adversely affected by any of the steps the material would be subjected to in the process, nor being volatile (or otherwise eliminated) at the temperature(s) they are incorporated in the compositions. Understandingly, the materials need also be compatible with their intended use, which in the present case may include for illustration being biocompatible, non-irritating, non-immunogenic, and having any such characteristic providing for their regulatory approval at a concentration adapted for efficacious pharmaceutic compositions as herein-disclosed.

Non-volatile liquids suitable for the present invention can be selected from: monofunctional or polyfunctional aliphatic esters (such as butyl lactate, dimethyl glutarate, dimethyl maleate, dimethyl methyl glutarate and lactic acid isoamyl ester); fatty esters (such as 2-ethylhexyl lactate, acetyl tributyl citrate, acetyl triethyl citrate, acetyl triethyl hexyl citrate, allyl hexanoate, benzyl benzoate, butyl butyryl lactate, Cu-Cis alkyl benzoate, a mixture of caprylyl caprate and caprylyl caprylate, decyl oleate, dibutyl adipate, dicaprylyl carbonate, dibutyl maleate, dibutyl sebacate, diethyl succinate, ethyl oleate, glyceryl monooleate, glyceryl monocaprate, glyceryl tricaprylate, glyceryl trioctanoate, isopropyl myristate, isopropyl palmitate, L-menthyl lactate, lauryl lactate, n-pentyl benzoate, PEG-6 caprylic/capric glycerides, propylene glycol monolaurate, propylene glycol monocaprylate, triacetin, triethyl citrate, triethyl o-acetylcitrate, tris(2-ethylhexyl) o-acetyl-citrate, tributyl o-acetylcitrate and tributyl citrate); cyclic organic esters (such as decanoic lactone, gamma decalactone, menthalactone and undecanoic lactone); fatty acids (such as caprylic acid, cyclohexane carboxylic acid, isostearic acid, lauric acid, linoleic acid, linolenic acid, myristic acid, oleic acid, palmitic acid and stearic acid); terpenes (such as citronellol, eugenol, farnesol, hinokitiol, D-limonene, linalool, menthol, menthone, neridol, terpineol and thymol); aromatic alcohols (such as benzyl alcohol); aromatic ethers (such as methoxy benzene); aldehydes (such as cinnamaldehyde); and combinations thereof In a particular embodiment, the non-volatile liquid that may be used to plasticize a WIBC as herein-disclosed is a polyfunctional aliphatic ester (PFAE), being a diester derivative of common dicarboxylic acids: namely adipic (C6), azelaic (C9) and sebacic (Cio) acids, the alcohol portion of the diesters generally falling in the Ci-C29 carbon number range, including linear and branched, even and odd numbered alcohols. Dibutyl adipate (e.g., commercially available as Cetiol® B) is an example of a PFAE suitable to plasticize a WIBC, in particular a WIBP, according to one embodiment. Alternative suitable examples are Cu-Cis alkyl benzoate (e.g., commercially available as Pelemol® 256) and dicaprylyl carbonate (e.g., commercially available as Cetiol® CC).

Polar medium The liquid medium forming the continuous phase in which the nano-elements including the WIBC and the carrier-insoluble active agent are dispersible is polar. In some embodiments, the liquid phase consists essentially of a polar carrier, whereas in other cases additional components can be present within the polar carrier. Such additional components can be, for illustration, surfactants, carrier-soluble active agents, or any other additives conventionally present in pharmaceutical compositions. A polar carrier suitable for the present invention can be selected from a group comprising water, glycols (e.g., propylene glycol, dipropylene glycol, and 1,2-butanediol 1,3-butanediol, 1,4-butanediol, 2-ethyl-1,3-hexanediol and 2-methy1-2-propy1-1,3-propanediol), glycerols including glycerol, precursors and derivatives thereof (e.g., acrolein, dihydroxyacetone, glyceric acid, tartronic acid, epichlorohydrin, glycerol tertiary butyl ether, polyglycerol, glycerol ester and glycerol carbonate) and combinations thereof.

A polar medium may be formed of one or more suitable polar carriers, the resulting liquid being often referred as an aqueous solution (or an aqueous phase) when water is the preponderant polar carrier. In some cases, a liquid deemed not sufficiently polar by itself (such as a fatty alcohol) can be present in the liquid phase in addition to the polar carrier(s), provided that the liquid insufficiently polar to form the entire liquid polar phase is a) soluble in the main polar carrier (e.g., having a water-solubility of 5 wt.% or more) so as to form a unique liquid phase therewith; and b) the overall polarity of the liquid phase is maintained. The polarity index of the resulting liquid phase may be of 3 or more, 4 or more, or 5 or more, water having for reference a polarity index of 9-10.

As the polarity index of a solvent refers to its relative ability to dissolve in test solutes, a liquid may additionally or alternatively be classified as polar or non-polar in view of its dielectric constant (Er). Liquids having a dielectric constant of less than 15 are generally considered non-polar, while liquids having a higher dielectric constant are considered polar, the relative polarity of a liquid increasing with the value of the dielectric constant. Preferably, the polar carrier suitable for the present compositions has a dielectric constant of 20 or more, 30 or more, 40 or more, 50 or more, or 60 or more, as established at room temperature. For illustration, the dielectric constant of propylene glycol is 32, the dielectric constant of glycerol is 46, and the dielectric constant of water is 80. While for simplicity, this guidance is provided for a neat polar carrier, this in fact should preferably apply to the entire polar liquid phase prepared therefrom (e.g., including additional polar-soluble materials and/or consisting of a mixture of liquid carriers). Noticeably, a liquid polar phase can be constituted of a mix of formally polar solvents (e.g., having Er? 15) with formally non-polar ones (e.g., having se< 15), as long as their respective volume allows for the entire liquid phase to be polar (e.g., having Er 15). The dielectric constant of a liquid is typically provided by the manufacturer but can be independently determined by any suitable method, such as described in ASTM-D924.

As discussed, the composition of the polar liquid phase should be such that the nano-elements including the WIBC and carrier-insoluble active agent can remain essentially non-soluble and stably dispersed therein, with no significant leaching of the contents of the nano-25 elements into their surrounding medium.

As the polar medium may comprise additional liquids and/or materials dissolved therein, the polar carrier can constitute at least 50 wt.%, at least 60 wt.%, at least 70 wt.%, at least 80 wt.%, or at least 90 wt.%, by weight of the liquid phase.

In a particular embodiment, the polar carrier comprises water (e.g., 45 wt.% water, 45 wt.% propylene glycol, and 10% of a fatty alcohol), consists of water (e.g., including between 51 wt.% and 80 wt.% of water), consists essentially of water (e.g., including between 81 wt.% and 99 wt..% of water), or is water.

As mentioned, the principles above detailed with respect to the polar carrier in which the nano-elements can be prepared may similarly apply to any other liquid vehicle to which the nano-elements might be transferred for the preparation of a liquid dosage form of a pharmaceutical composition.

Surfactants Some nano-elements may remain nano-dispersed in a liquid medium in view of their inherent chemical properties, the nano-elements for instance having a charge sufficient to ensure repulsion of the particles, consequently ensuring their stable dispersion. Other nano-elements may alternatively or additionally remain nano-dispersed if the WIBC has been plasticized with a non-volatile-liquid additionally serving as a surfactant to a sufficient extent.

However, in some embodiments, the composition may further comprise at least one surfactant, for the nano-elements to remain dispersed (hence also in their intended size range).

Surfactants suitable for the purpose of the present invention lower the surface tension between the nano-elements containing the WIBCs and the active agents, and the environment in which they are immersed. Depending on their chemical formula (and on the WIBC, active agent and polar carrier being considered), the surfactants can be miscible with the WIBCs or with the polar carrier wherein the nano-suspension is formed.

Surfactants suitable for the present compositions and methods are generally amphiphilic, containing a polar or hydrophilic part and a non-polar or hydrophobic part. Such surfactants may be characterized by Hydrophilic-Lipophilic Balance (HLB) values within the range of 1 to 35, wherein the HLB values, which generally imply compatibility with water systems, are typically provided on Griffin scale.

Suitable surfactants for the purpose of the present invention can be anionic, cationic, amphoteric or non-ionic surfactants.

Anionic surfactants can be selected from the group including: alkyl sulfates (e.g., sodium lauryl sulfate, ammonium lauryl sulfate and ammonium laureth sulfate); sulfosuccinates (e.g., disodium lauryl sulfosuccinate, disodium laureth sulfosuccinate, sodium dioctyl sulfosuccinate and their mixtures with sulfonic acids and lauramidopropyl betaine; alkyl benzene sulfonates (e.g., sodium tosylate, cumene sulfonate, toluene sulfonic acid, xylene sulfonic acid, cumene sulfonic acid and salts (e.g., sodium, potassium, calcium, ammonium) thereof); acyl methyl taurates (e.g., sodium methyl lauroyl taurate and sodium methyl cocoyl taurate); acyl sarcocinates (e.g., sodium lauroyl sarcosinate, sodium cocoyl sarcosinate and sodium myristoyl sarcosinate); isethionates (e.g., sodium butyl isethionate, sodium capryloyl isethionate and sodium lauroyl isethionate); propyl peptide condensates; monoglyceride sulfates; ether sulfonates and fatty acid salts (e.g., sodium stearoyl lactylate).

Cationic surfactants can be selected from the group including: quaternary ammonium 5 compounds (e.g., benzalkonium chloride, stearalkonium chloride, centrimonium chloride, and trimethyl ammonium methyl sulfates).

Amphoteric surfactants can be selected from the group including: betaines (e.g., cocamidopropyl betaine); alkylamphopropionates (e.g., cocoamphopropionate); alkyliminopropionates (e.g., sodium laurarninopropionate); and allcylamphoacetates (e.g., cocoampho-carboxyglycinate.

Non-ionic surfactants can be selected from the group including: fatty alcohols (e.g., cetearyl alcohol); ethoxylated fatty alcohols (e.g., Cs-C18 alcohol polyglycol, polyoxyl 6 stearate and polyoxyl 32 stearate); poly (ethylene glycol) block copolymers (e.g.; poloxamer); ethylene oxide (E0)/propylene oxide (PO) copolymers; alkylphenol ethoxylates (e.g., octylphenol polyglycol ether and nonylphenol polyglycol ether); alkyl glucosides and polyglucosides (e.g., lauryl glucoside); fatty alkanolamides (e.g., lauramide diethanolamine and cocamide diethanolamine); ethoxylated alkanolamides; ethoxylated fatty acids; sorbitan derivatives (e.g., polysorbates, sorbitan laurate, sorbitol, 1,4-sorbitan, iso-sorbide and 1,4sorbitan triester, PEG-80); alkyl carbohydrate esters (e.g., saccharose fatty acid monoester); amine oxides; ceteareths; oleths; alkyl amines; fatty acid esters (e.g., ascorbyl palmitate, ethylene glycol stearate, polyglycery1-6 esters, polyglycery1-6 pentaoleate, polyglyceryl-10 pentaoleate and polyglyceryl-10 pentaisostearate); polyoxylglycerides (e.g., oleoyl polyoxyl-6 glycerides); natural oil derivatives; ester carboxylate (e.g.. D-a-tocopherol polyethylene glycol succinate (vitamin E TPGS)); and urea.

These surfactants may be categorized into emulsifiers and hydrotropes, according to their mechanism of action. Emulsifiers readily form micelles (thus being characterized by a critical micelle concentration (CMC) value) and are believed to increase the dispersibility of the WIBC (or plasticized WIBC) when later combined with a polar carrier to yield a nano-suspension. As a rule, emulsifiers typically relate to surfactants ensuring the dispersion of one liquid into another, the liquids having opposite polarity, whereas dispersants relate to surfactants ensuring the dispersion of a solid into a liquid. As the present method may provide for nano-emulsions and nano-dispersions, surfactants referred to as emulsifiers at a step the nano-suspension is an emulsion, may in fact become dispersants, to the extent that an initial nano-emulsion later yields a nano-dispersion at a lower temperature. Hence, as used herein, the term "emulsifier(s)" also includes surfactants otherwise known as dispersants.

Emulsifiers that are lipophilic in nature, i.e., include a relatively large hydrophobic part, are more suitable to be combined with the WIBC (and any other material not miscible in the polar carrier, e.g., a non-volatile liquid), and may therefore be referred to as polar-carrier-insoluble emulsifiers (or surfactants, in general). Hence, such relatively hydrophobic emulsifiers are expected to be within the nano-elements of the composition. These relatively hydrophobic emulsifiers generally have HLB values of 9 or less, 8 or less, 7 or less, or 6 or less, on Griffin scale.

Emulsifiers that are more hydrophilic in nature have a relatively large hydrophilic part and would be more compatible with the polar phase of the composition, and may therefore be referred to as polar-carrier-soluble emulsifiers (or surfactants, in general). Such relatively hydrophilic emulsifiers generally have HLB values of 11 or more, 13 or more, 15 or more, 17 or more, or 20 or more.

Emulsifiers having HLB values within the range of 9 and 11 are considered "intermediate", the hydrophobic and hydrophilic parts of such emulsifiers being fairly well-balanced. Such intermediate emulsifiers can be added in the present methods either to the WIBC and carrier-insoluble active agent or to the polar carrier and may accordingly be found in the nano-elements or in their medium, the ability of a portion of such surfactants to migrate between the two phases being also envisioned.

In a particular embodiment, the surfactant serving as an emulsifier is selected from: vitamin E TPGS, poly (ethylene glycol) block copolymer, a mixture of polyoxyl 6 stearate type I, ethylene glycol stearates and polyoxyl 32 stearate type I (such as commercially available as Tefose® 63 from Gattefosse, France), mixtures comprising olive oil-derived extracts (such as commercially available under the brand Olivatis® from Medolla Iberia, Spain), ascorbyl palmitate, polyglyceryl-10 pentaoleate, polyglyceryl-10 pentaisostearate, oleoyl polyoxyl-6 glycerides (such as commercially available as Labrafil® M 1944 CS from Gattefosse, France), disodium laureth sulfosuccinate, disodium lauryl sulfosuccinate, a mixture of disodium lauryl sulfosuccinate, sodium C14-C16 olefin sulfonate and lauramidopropyl betaine (such as commercially available as Cola®Det EQ-154 from Colonial Chemical, USA) and a mixture of olive oil and glutamic acid (such as commercially available as Olivoil® glutamate from Kalichem, Italy).

While surfactants acting as emulsifiers are generally sufficient to stabilize nano-elements of the present compositions, the Inventors have found that when WIBCs are present at a relatively high concentration, as enabled by the invention, the addition of another type of surfactants, namely hydrotropes, assisted in achieving a satisfactory stability.

Hydrotropes are also amphiphilic molecules, but contrary to emulsifiers, they contain a relatively shorter lipophilic chain. As the lipophilic portion of the hydrotropes is generally too short to allow micelle formation, the hydrotropes alternatively solubilize hydrophobic compounds in the polar carrier and permit co-emulsification, together with the emulsifier. Generally, hydrotropes are miscible mainly in the polar carrier phase (e.g., aqueous phase) of the nano-suspension, and are characterized by having HLB values of 10 or more, 12 or more, 15 or more or 18 or more.

Suitable hydrotropes can be selected from the group including: sodium dioctyl sulfosuccinate, urea, sodium tosylate, adenosine triphosphate, cumene sulfonate, toluene sulfonic acid, xylene sulfonic acid, cumene sulfonic acid and salts thereof In a particular embodiment, the hydrotrope is selected from: sodium dioctyl sulfosuccinate, urea and a salt of xylene sulfonic acid, such as ammonium xylenesulfonate.

Active agents The nano-elements made of the WIBC further comprise one or more polar-carrierinsoluble active agent(s) within their matrix. Such carrier-insoluble active agent(s) are generally miscible with the components included therein, i.e., with the WIBCs, and the optional nonvolatile liquid and emulsifier. The constituents of the nano-elements are miscible one with the other when forming a unique phase.

In some embodiments, the carrier-insoluble active agent has a molecular weight of no more than 1,000 g/mol, or no more than 500 g/mol, in particular if passive cell permeability is expected at the site of delivery. However, as an active agent may be effective for the diagnosis or treatment of a disease in a living subject without having to penetrate particular target cells, the carrier-insoluble active agents that can be incorporated into the nano-elements of WIBCs need not be limited to such MW.

Thus, advantageously, the carrier-insoluble active agent can also have a MW of more than 1,000 g/mol, being for instance of at least 1,200 g/mol, at least 1,400 g/mol, at least 1,600 g/mol, or at least 1,800 g/mol. Typically, the MW of a carrier-insoluble active agent that can be incorporated into nano-elements having an average diameter of 200 nm or less does not exceed 500 kDa. In some embodiments, the MW of the carrier-insoluble active agent is 400 kDa or less, 300 kDa or less, 200 kDa or less, or 100 kDa or less. In particular embodiments, the carrier-insoluble active agent has a molecular weight not exceeding 50 lcDa, not exceeding 40 kDa, not exceeding 30 kDa, not exceeding 20 kDa, not exceeding 10 kDa, or not exceeding 5 kDa.

In some embodiments, and similar to the WIBC and non-volatile liquid described above, the carrier-insoluble active agent should have a solubility of 5 wt.% or less, 4 wt.% or less, 3 wt.% or less, 2 wt.% or less, 1 wt.% or less, 0.5 wt.% or less, or 0.1 wt.% or less by weight of the polar carrier or the liquid phase including it.

While the present invention is mainly concerned by the ability of its nano-elements consisting of WIBCs to deliver the carrier-insoluble active agents contained therein, so as to provide efficacious pharmaceutical compositions, such drugs need not be the only ones present in a final dosage form. Other active agents could be included in pharmaceutical compositions according to the present teachings, the additional active agents being external to the nano-elements. For illustration, the composition can be adapted for administration as a liquid dosage form, in which case the additional active agents can be dispersed or dissolved in the liquid vehicle in which the nano-elements are dispersed.

Volatile organic compounds The presence of volatile organic compounds, having a high vapor pressure and low boiling point at room temperature, is unwanted, especially in materials to be used in the pharmaceutical industries. As used herein, the term -volatile organic compound" ("VOC") refers to an organic compound having a vapor pressure of 0.1 kPa or more, as measured at a temperature of 20°C.

Specific agents that may be considered as VOCs for the purpose of the present teachings, are solvents that are capable of dissolving the WIBCs used to prepare the nano-elements. Such agents include, but are not limited to: acetone, acetonitrile, aniline, benzene, carbon tetrachloride, chloroform, cyclohexanone, dichloromethane, dioxane, dimethylesulfoxide, ethyl acetate, hexafluoroisopropyl alcohol, methylene chloride, N,N-dimethylformamide, 2-nitropropane, 1,1,2,2-tetrachloroethane, tetrahydofuran, 1,1,2-trichloroethane and toluene.

As opposed to commonly used methods for preparing nano-carriers, the present invention does not utilize an emulsification technique, and hence, the WIBC (specifically WIBP) is not dissolved in a solvent (such as a VOC) that will later need to be removed.

In some embodiments, the nano-elements of WIBC contain less than 2 wt.%, less than 1.5 wt.%, or less than 1 wt.%, less than 0.5 wt.%, less than 0.4 wt.%, less than 0.3 wt.%, less than 0.2 wt.%, or less than 0 1 wt.%, less than 0.09 wt.%, less than 0 08 wt.%, less than 0.07 wt.%, less than 0.06 wt.%, less than 0.05 wt.%, less than 0.04 wt.%, less than 0.03 wt.%, or less than 0.02 wt.% of a VOC by weight of the nano-elements. In some embodiments, the nano-elements are devoid of any VOC, but may contain up to 0.001 wt.%, up to 0.002 wt.%, up to 0.003 wt.%, up to 0.004 wt.%, up to 0.005 wt.%, up to 0.006 wt.%, up to 0.007 wt.%, up to 0.008 wt.%, up to 0.009 wt.%, or up to 0.01 wt.% of a VOC by weight of the nano-elements. The above-mentioned amounts are cumulative in case of more than one VOC being present in the nano-elements.

In particular embodiments, the nano-elements contain between 0.001 wt.% and 0.5 wt.%, between 0.002 wt.% and 0.4 wt.%, between 0.003 wt.% and 0.3 wt.%, between 0.004 wt.% and 0.2 wt.%, between 0.005 wt.% and 0 1 wt.%, between 0.001 wt.% and 0.09 wt.%, between 0.002 wt.% and 0.08 wt.%, between 0.003 wt.% and 0.07 wt.%, between 0.004 wt.% and 0.06 wt.%, or between 0.005 wt.% and 0 05 wt.% of a VOC by weight of the nano-elements.

The nature and amount of potential VOCs in nano-elements can be determined by routine 20 analysis, e.g., by Gas Chromatogaphy, using standard methods such as described in ASTM D4526 or VDA 277.

Compositions Having reviewed the various components that may be used in the present pharmaceutical compositions, suitable concentrations or respective proportions shall be provided below. It is to be noted that some of the components according to the present teachings can serve in more than one role. Thus, when referring to the concentration of a certain component in a pharmaceutical composition, the information refers only to dedicated compounds intentionally added to serve this role, excluding compounds having a different primary role in the composition.

In some embodiments, the concentration of the WIBC (or combination thereof) in the 30 nano-elements is within the range of 0.1 wt.% to 100 wt.% by total weight of the nano-elements, (wherein 100 wt.% refers to nano-elements comprising only WIBC(s) for which the presence of a plasticizing liquid or of a surfactant is not required). In some embodiments, the concentration of the WIBC(s) is within the range of 1 wt.% to 90 wt.%, 5 wt.% to 80 wt.%, 10 wt.% to 50 wt.%, or 15 wt.% to 40 wt.% by total weight of the nano-elements.

In some embodiments, the concentration of the WIBC(s) in the pharmaceutical composition is within the range of 0.1 wt.% to 30 wt.% by total weight of the composition, preferably in the range of 0.5 wt.% to 13 wt.%, 1 wt.% to 10 wt.%, 2 wt.% to 10 wt.%, 3 wt.% to 10 wt.%, 4 wt.% to 10 wt.%, or of 4 wt.% to 8 wt.%. In other embodiments, the WIBC(s) concentration is at least 0.1 wt.%, at least 0.5 wt.%, at least 1 wt.%, at least 2 wt.%, at least 3 wt.%, or at least 4 wt.% by total weight of the composition. In other embodiments, the concentration of the WIBC(s) is at most 30 wt.%, at most 25 wt.%, at most 20 wt.%, at most 15 wt.%, at most 13 wt.%, at most 10 wt.% or at most 8 wt.% by total weight of the composition.

In some embodiments, the concentration of the carrier-insoluble active agent in the nano-elements, is within the range of 0.1 wt.% to 99.9 wt.%, within the range of 1 wt.% to 85 wt.%, within the range of 2 wt.% to 70 wt.%, within the range of 3 wt.% to 55 wt.%, within the range of 5 wt.% to 45 wt.%, within the range of 5 wt.% to 35 wt.%, within the range of 10 wt.% to 30 wt.%, or within the range of 15 wt.% to 25 wt.% by total weight of the nano-elements.

In some embodiments, the concentration of the carrier-insoluble active agent in the pharmaceutical composition is within the range of 0.01 wt.% to 30 wt.% by total weight of the composition, preferably in the range of 0.05 wt.% to 25 wt.%, 0.1 wt.% to 20 wt.%, 0.5 wt.% to 15 wt.%, 1 wt.% to 12.5 wt.%, 2 wt.% to 10 wt.%, 3 wt.% to 10 wt.%, or of 5 wt.% to 10 wt.%. In some embodiments, the concentration of any one of the active agents is at least 0.01 wt.%, at least 0.05 wt.%, at least 0.1 wt.%, at least 0.5 wt.%, at least 1 wt.%, at least 2 wt.%, at least 3 wt.%, or at least 5 wt.% by total weight of the composition. In other embodiments, the concentration of all the active agents or the sole one is at most 30 wt.%, at most 25 wt.%, at most 20 wt.%, at most 15 wt.%, at most 12.5 wt.%, or at most 10 wt.% by total weight of the composition.

In some embodiments, the polar carrier (e.g., water) is present in the pharmaceutical composition being a liquid dosage form within the range of 30 wt.% to 90 wt.%, 30 wt.% to 80 wt.%, 40 wt.% to 70 wt.%, or 30 wt.% to 60 wt.% by total weight of the composition. As mentioned, the nano-elements may alternatively be isolated to form a pharmaceutical composition being a dry dosage form, hence substantially devoid of any liquid vehicle, whether polar or not.

In some embodiments, the concentration of the non-volatile liquid(s), if present in the nano-elements, is at most 99 wt.%, at most 90 wt.%, at most 80 wt.%, at most 70 wt.%, or at most 60 wt.% by total weight of the nano-elements.

In some embodiments, the concentration of the non-volatile liquid(s), if present in the pharmaceutical composition, is within the range of 0.1 wt.% to 50 wt.% by total weight of the composition, preferably in the range of 0.1 wt.% to 45 wt.%, 0.1 wt.% to 40 wt.%, 0.5 wt.% to 35 wt.%, 0.5 wt.% to 30 wt.%, 0.5 wt.% to 25 wt.%, 1 wt.% to 22.5 wt.%, or of 5 wt.% to 20 wt.%. In some embodiments, the concentration of the non-volatile liquid(s) is at least 0.1 wt.%, at least 0.5 wt.%, at least 1 wt.%, or at least 5 wt.% by weight of the pharmaceutical composition.

In other embodiments, the concentration of the non-volatile liquid(s) is at most 50 wt.%, at most 45 wt.%, at most 40 wt.%, at most 35 wt.%, at most 30 wt.%, at most 25 wt.%, at most 22.5 wt.%, or at most 20 wt.% by weight of the pharmaceutical composition. The non-volatile liquid(s) (or a combination thereof) can be included for plasticizing at a weight ratio of at least 1:200, at least 1:20, at least 1:10, at least 1:5, or at least 1:3, at least 1:1, at least 2:1, or at least 3:1, with respect to the weight of the WIBC(s) to be plasticized. In some embodiments, the weight ratio of the non-volatile liquid(s) to the WIBC(s) is of at most 100:1, at most 50:1, at most 20:1, at most 10:1, or at most 5:1.

In some embodiments, the concentration of the surfactant(s), if present in the nano-elements, is within the range of 0.1 wt.% to 50 wt.%, within the range of 1 wt.% to 50 wt.%, within the range of 5 wt.% to 50 wt.%, within the range of 10 wt.% to 50 wt.%, within the range of 15 wt.% to 45 wt.%, or within the range of 20 wt.% to 40 wt.% by total weight of the nano-elements.

In some embodiments, the combined concentration of the surfactants (including, for instance, the emulsifiers and/or hydrotropes), if present in the pharmaceutical composition, is within the range of 0.1 wt.% to 60 wt%, within the range of 0.5 wt.% to 60 wt.%, within the range of 1 wt.% to 60 wt.%, 5 wt.% to 40 wt.%, 6 wt.% to 30 wt.%, 7 wt.% to 25 wt.%, 8 wt.% to 20 wt.%, or 5 wt.% to 15 wt.% by total weight of the composition. In some embodiments, the combined concentration of the surfactants is at least 5 wt.%, at least 6 wt.%, at least 7 wt.%, or at least 8 wt.% by total weight of the composition. In other embodiments, the combined concentration of the surfactants is at most 40 wt.%, at most 35 wt.%, at most 30 wt.%, at most 25 wt.%, at most 20 wt.% or at most 15 wt.% by total weight of the composition.

In some embodiments, the concentration of the emulsifier(s), if present in the pharmaceutical composition, is within the range of 0.01 wt.% to 60 wt.%, 0.1 wt.% to 50 wt.%, 0.5 wt.% to 40 wt.%, 1 wt.% to 30 wt.%, 3 wt.% to 25 wt.%, or 5 wt.% to 20 wt.% by total weight of the composition. In some embodiments, the concentration of the emulsifier(s) in the composition is at least 0.01 wt.%, at least 0.1 wt.%, at least 0.5 wt.%, at least 1 wt.%, at least 3 wt.%, or at least 5 wt.% by total weight of the composition. In other embodiments, the concentration of the emulsifier(s) in the composition is at most 60 wt.%, at most 50 wt.%, at most 40 wt.%, at most 30 wt.%, at most 25 wt.%, or at most 20 wt.% by total weight of the composition.

In some embodiments, the concentration of the hydrotrope(s), if present in the pharmaceutical composition, is within the range of 0.01 wt% to 60 wt.%, 0.05 wt.% to 50 wt.%, 0.1 wt.% to 40 wt.%, 0.1 wt.% to 30 wt.%, 0.5 wt.% to 25 wt.%, 1 wt.% to 20 wt.%, or 1 wt.% to 10 wt.% by total weight of the composition. In some embodiments, the hydrotrope(s) concentration in the composition is at least 0.01 wt.%, at least 0.05 wt.%, at least 0.1 wt.%, at least 0.5 wt.%, or at least 1 wt.% by total weight of the composition. In other embodiments, the hydrotrope(s) concentration in the composition is at most 60 wt.%, at most 50 wt.%, at most 40 wt.%, at most 30 wt.%, at most 25 wt.%, at most 20 wt.%, at most 15 wt.%, or at most 10 wt.% by total weight of the composition.

Preferably, the aforesaid ingredients are approved for use at the envisioned concentrations for the diagnostic or treatment of ailments in living subjects. For instance, they do not lead to allergic reactions, or any other acute or chronic adverse effect, whether administered to an animal subject or to an edible plant that may be consumed by the animals. Moreover, all ingredients need be compatible one with another, such compatibility being as described above. As readily understood, this principle of compatibility, which can be affected not only by the chemical identity of the materials, but by their relative proportions according to the intended use, should preferably guide the selection of all materials necessary for the compositions disclosed herein.

Method of preparation In another aspect of the present invention, there is provided a method for preparing a nano-elements of a water-insoluble biodegradable compound (WIBC), in particular of a water-insoluble biodegradable polymer (WIBP), the nano-elements further including a polar-carrierinsoluble active agent, and being dispersible as a nano-suspension in a polar liquid. The nano-elements that can be prepared by the present methods are adapted for the pharmaceutical compositions herein described, so that the properties and characteristics of the materials used in the present method are as described above for each of the materials. Notably, the nano-elements including the WIBCs and the active agents are substantially free of VOC compounds and contain less than 2 wt.% of VOCs per weight of the nano-elements.

The steps of the present method are briefly displayed in Figure 1 and further detailed hereinbelow, a step having a dashed contour being optional.

In a first step (S01) of the method, at least one WIBC (e.g., at least one WIBP) is provided.

In a second step (S02) of the method, at least one polar-carrier-insoluble active agent is provided and combined with the WIBC(s).

In a third step (S03) of the method, the WIBC(s) and the polar-carrier-insoluble active agent(s) can be mixed with one or more non-volatile liquid(s), whereby the WIBC(s) undergo(es) plasticizing by the liquid. This step is optional as the viscosity of the WIBC(s) provided in SO1 can be sufficiently low for further processing (e.g., 10 mPa-s or less, as measured at a temperature of 50°C and a shear rate of 10 sec-1), the polar-carrier-insoluble active agent(s) optionally also plasticizing the WIBC(s).

If intentional plasticizing of the WIBC(s) is desired, the mixing with the non-volatile liquid(s) can be performed at any mixing temperature and/or mixing pressure suitable for such compounding.

The temperature at which the plasticizing is performed is typically selected according to temperatures characterizing the substances involved in the process, for instance, by taking into account a Ts, Tm and/or Tg characterizing the WIBC(s) and, optionally, a Tb of the non-volatile liquid(s) (referred to as Tbi). As previously detailed, a mixing temperature would suitably be higher than at least one of the characterizing temperatures of the WIBC(s) and lower than the boiling temperature of the plasticizing liquid at a pressure the mixing step is performed, though this upper limit is not essential as long as the selected mixing temperature does not significantly boil away the plasticizing liquid. Hence, in some cases, the mixing temperature can even be at Tbr if the step is brief enough and/or the non-volatile liquid in sufficient excess and/or the mixing performed in a chamber sufficiently sealed to limit its evaporation / favor its condensation back to the mixture.

One can readily appreciate that a change in the properties of the substance reflected by these temperatures dropping from first to second values can alternatively take place at a lower mixing temperature or a higher mixing temperature, if the pressure in a sealed chamber hosting the mixing process ensuring plasticization of the WIBC(s) were to be accordingly reduced or increased. Therefore, while in the description of a method suitable for the preparation of a composition according to the present teachings, reference can be made to specific temperatures and duration of times assuming the process is carried out under standard atmospheric pressure, such guidance should not be viewed as limiting, and all temperatures and durations achieving a similar outcome with respect to the behavior of the plasticized WIBC(s) are encompassed.

It is noted in this context, when the WIBC is a WIBP, that while the Tm and/or Tg of a polymer may set relatively clear temperatures below and above which a polymer may display a distinct behavior, this typically does not apply to the Ts. In view of their viscoelastic properties, a polymer or a plasticized polymer may remain "sufficiently solid" even at a temperature moderately higher than its formal softening point.

The plasticizing can be performed under a variety of conditions, such as elevated temperatures (i.e., 30°C or more, e.g., at 40°C or more, at 50°C or more, at 60°C or more, at 75°C or more, or at 90°C or more) and/or elevated pressure (i.e., 100 kPa or more, e.g., at 125 kPa or more, 150 kPa or more, 175 kPa or more, 200 kPa or more, 250 kPa or more, or 300 kPa or more), typically accelerating the plasticizing process (Le., shortening the duration of the plasticizing period) or enabling a desired modification of a boiling temperature Tbi at which the non-volatile liquid might evaporate. As mixing at elevated pressure increases Tbr, the range of temperatures at which plasticizing could be performed can be accordingly widened. Conversely, plasticizing the WIBC using the non-volatile liquid under conditions less favorable than arbitrarily set to assess the ability of a WIBC to be plasticized by a specific agent, such as at a temperature of less than 50°C and/or a reduced pressure of less than 100 kPa, may prolong the plasticizing process, if desired. The ability of a WIBC to be plasticized by a particular nonvolatile liquid may be assessed under any one of the above temperature or pressure conditions.

Mixing of the WIBC(s) with or within the non-volatile liquid(s) by agitating the mixture can also shorten the plasticizing period, such agitating additionally ensuring that all parts of the WIBC(s) are plasticized in a relatively uniform manner, the plasticized WIBC behaving reasonably homogeneously with respect to subsequent steps of the method and results expected therefrom. If excess of the non-volatile liquid is used during the plasticizing process, it can be optionally removed before proceeding to following step(s). When the materials to be plasticized have a relatively high viscosity, the mixing step can also be referred to as compounding, and the mixing equipment can be accordingly selected.

The duration of plasticizing will inter alia depend on the WIBC(s) being plasticized, the non-volatile liquid(s) being used, the plasticizing conditions (e.g., temperature, pressure, and/or agitation), and the desired extent of plasticizing. The plasticizing period can be of at least 1 minute and at most 4 days. The plasticizing conditions and its duration need also be suitable to the active agent(s) to be incorporated into the WIBC(s) being plasticized.

In some embodiments, additional materials may be incorporated within the WIBC(s) being plasticized and added during the mixing step S03. These materials, which are typically insoluble in the polar carrier, can be at least one polar-carrier-insoluble surfactant, the surfactant(s) possibly serving as an emulsifier, or any other desirable additive. The plasticizing conditions may be adapted to the presence of such additional constituents.

The mixing may be performed by any method known to the skilled artisan, such as: sonication, using a double jacket planetary mixer or extruder, etc. When the materials being mixed have a relatively high viscosity, the mixing step can be performed with a two-roll mill, a three-roll mill and such type of equipment. In a particular embodiment, the mixing is performed by sonication.

In a fourth step (SO4) of the method, the mixture of the polar carrier-insoluble active agent(s) and the WIBC(s) (optionally plasticized, and further optionally, containing at least one surfactant) is combined with at least one polar carrier. At least one surfactant can be added, if desired, at this step, the surfactant being a relatively polar emulsifier or a hydrotrope. Additional materials which are soluble in the polar carrier could also be added at this step but may equally be introduced after the following nano-sizing step.

The mixture is nano-sized in a fifth step (SOS) to form a nano-suspension, whereby nano-elements of WIBC(s) containing the polar-carrier-insoluble active agent(s), and optionally other polar-carrier-insoluble materials, are dispersed in a polar liquid including the polar carrier optionally combined with other polar materials.

As the nano-sizing is typically performed by applying shear at a relatively elevated temperature, the nano-elements including the WIBC(s) and the polar-carrier-insoluble active agent(s) are generally nano-droplets during that step and the resulting nano-suspension is a nano-emulsion.

The nano-emulsion can be obtained by nano-sizing the mixture of desired materials by any method capable of shearing the WIBC (whether plasticized or not, or including additional compounds), the shearing method being selected from the group comprising: sonication, milling, attrition, high pressure homogenization, high shear mixing and high shear microfluidization. In a particular embodiment, the nano-sizing is performed by sonication.

The nano-sizing is performed at a shearing temperature that is at least equal to at least one of the first Ts, Tm and Tg of the WIBC, at least equal to at least one of the second Ts, Tm and Tg of the WIBC if plasticized, and can be, in some embodiments, at least 5°C higher, at least 10°C higher, or at least 15°C higher than the highest characterizing temperature of the WIBC mix being sheared. However, while this is not essential if the shearing step is brief enough and/or the polar liquid in sufficient excess, the shearing temperature should preferably prevent significant amounts of the liquid phase being boiled away. In some embodiments, the nano-sizing temperature at which shearing is performed does not exceed the boiling temperature of the liquid phase in which the shearing is being performed or of any other liquid the evaporation of which should be prevented. Thus, the shearing temperature is generally lower than the lowest of the Tb of the polar carrier(s) (referred to as The) at a pressure the nano-sizing step is performed. For instance, when the polar carrier is water, the shearing temperature can be selected to be lower than 95°C, lower than 90°C, lower than 85°C, or lower than 80°C, assuming the nano-sizing is performed at atmospheric pressure. However, if the nano-sizing were to be performed at an elevated pressure, the Tb e of the polar carrier would be raised and the shearing temperature could be accordingly increased. Still illustrating with water, while its Tb is 100°C at about 100 kPa, this boiling temperature raises to 120°C at about 200 kPa, in which case the nanosizing temperature not to be exceeded could be of up to 115°C. As mentioned, these upper limits while preferred are not essential, as a part of the polar carrier being boiled away could be prevented at even higher temperatures if the step is brief enough, and/or the polar carrier in sufficient excess and/or the nano-sizing is performed in a chamber sufficiently sealed to limit its evaporation / favor its condensation back to the nano-suspension.

At shearing temperatures in this range of higher than Ts, Tm or Tg and optionally lower than Tb, the WIBC(s), and in particular the WIBP(s), can completely melt and the nano-sizing process can be considered as "melt nano-emulsification".

In some embodiments, at least 50% of the total number (DN50) or volume (Dv50) of the nano-elements (e.g., nano-droplets or nano-particles) formed in this nano-sizing step have a hydrodynamic diameter of up to 200 run, up to 150 run, up to 100 nm, up to 90 nm, up to 80 nm, or up to 70 nm. In some embodiments, the median diameter of the nano-elements is at least 5 rim, at least 10 rim, at least 15 nm, or at least 20 nm Advantageously, such values are applicable as determined by the volume of the nano-elements, the values determined by number being typically lower, and generally measured at room temperature.

As readily appreciated, depending on the temperatures characterizing the materials of the nano-elements and/or on the temperature at which measurements may be performed, the nano-elements can either be relatively liquid nano-droplets or relatively solid nano-particles, as the temperature is reduced. The size of the nano-particles at room temperature is commensurate with the size of the nano-droplets or slightly more compact, their median diameter not exceeding 200 nm.

In some embodiments, the size of the nano-particles or nano-droplets is determined by microscopy techniques, as known in the art (e.g., by Cryo TEM). In some embodiments, the size of the nano-elements is determined by Dynamic Light Scattering (DLS). In DLS techniques the particles are approximated to spheres of equivalent behavior and the size can be provided in term of hydrodynamic diameter. DLS also allows assessing the size distribution of a population of nano-elements.

Distribution results can be expressed in terms of the hydrodynamic diameter for a given percentage of the cumulative particle size distribution, either in terms of numbers of particles or volumes, and are typically provided for 10%, 50% and 90% of the cumulative particle size distribution. For instance, D50 refers to the maximum hydrodynamic diameter below which 50% of the sample volume or number of particles, as the case may be, exists and is interchangeably termed the median diameter per volume (Dv50) or per number (DN50), respectively, and often more simply the average diameter.

In some embodiments, the nano-elements of the disclosure have a cumulative particle size distribution of D90 of 500 nm or less, or a D95 of 500 rim or less, or a D97.5 of 500 nm or less or a D99 of 500 rim or less, i.e., 90%, 95%, 97.5% or 99% of the sample volume or number of 25 particles respectively, have a hydrodynamic diameter of no greater than 500 rim In some embodiments, the cumulative particle size distribution of the population of nano-elements (e.g., nano-particles) is assessed in term of number of particles (denoted DN) or in term of volume of the sample (denoted Dv) comprising particles having a given hydrodynamic diameter.

Any hydrodynamic diameter having a cumulative particle size distribution of 90% or 95% or 97.5% or 99% of the particles population, whether in terms of number of particles or volume of sample, may be referred to hereinafter as the "maximum diameter", i.e., the maximum hydrodynamic diameter of particles present in the population at the respective cumulative size distribution.

It is to be understood that the term "maximum diameter" is not intended to limit the scope of the present teachings to nano-particles having a perfect spherical shape. This term as used herein encompasses any representative dimension of the particles at cumulative particle size distribution of at least 90%, e.g., 90%, 95%, 97.5% or 99%, or any other intermediate value, of the distribution of the population.

The nano-particles or nano-droplets may, in some embodiments, be uniformly shaped and/or within a symmetrical distribution relative to a median value of the population and/or within a relatively narrow size distribution.

A particle size distribution is said to be relatively narrow if at least one of the following conditions applies: A) the difference between the hydrodynamic diameter of 90% of the nano-elements and the hydrodynamic diameter of 10% of the nano-elements is equal to or less than 200 nm, equal to or less than 150 rim, or equal to or less than 100 rim, or equal to or less than 50 nit, which can be mathematically expressed by: (D90 -D10) < 200 nm and so on; B) the ratio between a) the difference between the hydrodynamic diameter of 90% of the nano-elements and the hydrodynamic diameter of 10% of the nano-elements; and b) the hydrodynamic diameter of 50% of the nano-elements, is no more than 2.0, or no more than 1.5, or even no more than 1.0, which can be mathematically expressed by: (D90 -D10)/D50 < 20 and so on; and C) the polydispersity index of the nano-elements is equal to or less than 0.4, or equal to or less than 0.3, or equal to or less than 0.2, which can be mathematically expressed by: PDI = cr2/d2 <0.4 and so on, wherein a is the standard deviation of the particles distribution and d is the mean size of the particles, the PDI optionally being equal to 0.01 or more, 0.05 or more, or 0.1 or more.

In a sixth step (506) of the method, the nano-emulsion may be optionally actively cooled down to a temperature below the Tm, Ts or Tg of the WIBC (or plasticized WIBC), to accelerate the relative solidification of the nano-elements, if desired in manufacturing. Such active cooling can be achieved by refrigerating the nano-suspension (e.g., placing in a coolant having a desired low temperature), by subjecting the nano-suspension to ongoing agitation to accelerate heat dissipation (and incidentally maintain proper dispersion of the nano-droplets as they cool down), or by combining both approaches. This cooling step is optional, as the nano-emulsions may be allowed to passively cool down without any agitation upon termination of nano-sizing.

In a further optional seventh step (507) of the method, a polar-carrier-soluble active agent can be added and dissolved by stirring in the polar carrier. While depicted in the figure as a separate step following cooling of the nano-suspension whether active (506) or passive, the addition of any polar-carrier-soluble material might alternatively be performed prior to or during cooling.

In yet another optional eighth step (SOS) of the method, the nano-elements can be isolated from the polar carrier. This step allows the isolated nano-elements to be later combined with suitable excipients, depending on the type of dosage form they are to be incorporated within. For instance, if the dosage form is in a dry form, the isolated nano-elements can be mixed with the adequate excipient to form a dry dosage form (e.g., a tablet or capsule). If, the dosage form is in a liquid form (e.g., to be administered intravenously), such a step may serve to transfer the isolated nano-elements from the polar carrier to a different liquid vehicle adapted to the desired liquid dosage form.

While in the method detailed above, some ingredients have been described as being introduced (or optionally introduced) in the composition at a particular step, this should not be construed as limiting. For instance, the polar-carrier-insoluble active agents may, depending on the material they are selected from, be added to the WIBC after step SO! (as a separate step 802), or during step 503, together with the non-volatile liquid, if added.

Thus, the above-described steps can be modified, omitted (e.g., S03, SO6, S07 or S08) and additional steps may be included. For instance, the composition may comprise any additive customary to pharmaceutical compositions, such as diluents, extenders, binders, lubricants, disintegrating agents, coloring agents, flavoring agents, moisturizers, emollients, humectants, UV-protective agents, thickeners, preservatives, antioxidants, bactericides, fungicides, chelating agents, vitamins and fragrances, the nature and concentration of which need not be further detailed herein. The additives may be added during steps of the method already described or via new steps. Furthermore, the composition may be further treated (e.g., sterilized, filtered, etc.) in accordance with health regulations, to make it suitable for pharmaceutical uses.

Advantageously, the present method does not seek to chemically modify its active ingredients. The absence of such modifications in the present compositions is expected to prevent formation of large particles, having difficulties reaching their target sites due to their size, and/or is believed to prevent an undesirable decrease in the biological activity these ingredients might provide in their native (unmodified) form, assuming they are successfully delivered to their target site.

In other aspects, there are provided therapeutic uses of the present compositions, as enabled by the delivery of efficacious amounts of the polar-carrier-insoluble active agents, contained within the nano-elements. The pharmaceutical compositions can be used as analgesics, anesthetics, anti-addiction agents, antibacterials, anticonvulsants, antidementia agents, antidepressants, antiemetics, antifungals, antigout agents, anti-inflatnmatories, antimigraine agents, antimyasthenic agents, antimycobacterials, antineoplastics, anti-obesity agents, antiparasitics, antiparkinson agents, antipsychotics, antispasticity agents, antivirals, anxiolytics, bipolar agents, blood glucose regulators, blood products, cardiovascular agents, central nervous system agents, contraceptives, dental and oral agents, dermatological agents, electrolytes, minerals, metals, vitamins, gastrointestinal agents, genitourinary agents, hormonal agents (adrenal), hormonal agents (pituitary), hormonal agents (prostaglandins), hormonal agents (sex hormones), hormonal agents (thyroid), hormone suppressant (adrenal), hormone suppressant (pituitary), hormone suppressant (thyroid), immunological agents, infertility agents, inflammatory bowel disease agents, metabolic bone disease agents, ophthalmic agents, otic agents, respiratory tract agents, sexual disorder agents, skeletal muscle relaxants and sleep disorder agents. The compositions may also be used for diagnostic purposes in animal subject or for the treatment of plants. Preparation of the pharmaceutical compositions for such uses and their mode of application can be conventionally conducted and implemented, and need not be detailed herein.

EXAMPLES 25 Materials The materials used in the following examples are listed in Table 1 below. The reported properties were retrieved from the product data sheets provided by the respective suppliers or estimated by standard methods. Unless otherwise stated, all materials were purchased at highest available purity level. N/A means that a particular information is not available.

Table 1

Chemical name Commercial name MW Supplier CAS No. Water-insoluble biodegradable compound (WIBC) Polycaprolactone (PCL) Polycaprolactone (PCL-14) 14 kDa Sigma- 24980-41-4 Aldrich®, USA Polycaprolactone (PCL-25) 25 kDa Polysciences Inc., USA Polycaprolactone (PCL-37) 37 kDa Polycaprolactone (PCL-45) 45 kDa Sigma-Aldrich®, USA Polycaprolactone (PCL-80) 80 kDa Polylactic acid (PLA) Ecosoft® 608XF N/A Micro Powders inc., USA 9051-89-2 Coenzyme Q10 Coenzyme Q10 863.3 Thermo Fisher Scientific, USA 303-98-0 Non-volatile liquids Dibutyl adipate Cetiol® B 258.36 g/mol BASF®, Germany 105-99-7 Ct2-Cis alkyl benzoate Pelemol® 256 N/A Phoenix 68411-27-8 Chemical, Inc., USA Dicaprylyl carbonate Cetiol® CC 286.4 g/mol BASF®, Germany 1680-31-5 Surfactants (emulsifiers) D-a-tocopherol polyethylene glycol 1000 succinate Vitamin E TPGS -1,513 g/mol Antares Health Products, USA 9002-96-4 Poloxamer (poly(ethylene glycol)-block-poly(propylene glycol)-blockpoly(ethylene glycol)) Kolliphor® P407 9,840 to BASF®, Germany 691397-13-4 14,600 g/mol Mixture of: Tefose® 63 N/A Gattefosse, France 9004-99-3 polyoxyl 6 stearate type I, 111-60-4 ethylene glycol stearates and Chemical name Commercial name MW Supplier CAS No. polyoxyl 32 stearate type I Mixture of: Olivatis® 12C N/A Medolla Iberia, Spain N/A olive oil polyglycery1-6 esters and polyglycery1-6 pentaoleate Olive oil PEG-8 esters Olivatis® 15C 103819-46-1 Mixture of: olive oil polyglycery1-6 esters, Olivatis® 18C 85711-62-2 sodium stearoyl lactylate and cetearyl alcohol 25383-99 67762-27-0 Mixture of: Olivatis® 20C 85711-62-2 olive oil 110615-47-9 polyglycery1-6 esters and lauryl glucoside Mixture of: olive oil PEG-6 esters and olive oil polyglycery1-6 esters Olivatis® 21C N/A Ascorbyl palmitate Ascorbyl palmitate 414.5 g/mol Spec-Chem Industry, China 137-66-6 Polyglyceryl-10 pentaoleate Nikko! Decaglyn 5-0V N/A NIKKO Chemicals, Japan 86637-84-5 Polyglyceryl-10 pentaisostearate Nikko! Decaglyn 5-ISV N/A 126449-40-9 Oleoyl polyoxy1-6 glycerides Labrafil® M 1944 CS N/A Gattefosse, France 69071-70-1 Disodium laureth sulfosuccinate Texapon® SB 3 KC 410.4 g/mol BASF®, Germany 68815-56-5 Miconate LES(B) N/A Miwon Specialty Chemicals, Korea 39354-45-5 Disodium lauryl sulfosuccinate Miconate DLS(P) 454.5 g/mol 13192-12-6 Chemical name Commercial name MW Supplier CAS No. Mixture of: disodium lauryl sulfosuccinate, sodium C14-C16 Cola®Det EQ-154 N/A Colonial Chemical, USA 26838-05-1 olefin sulfonate and lauramidopropyl betaine 68439-57-6 4292-10-8 Mixture of: olive oil and glutamic acid Olivoil® glutamate N/A Kalichem, Italy 67762-27-0 8005-44-5 31566-31-1 Surfactants (hydrotropes) Sodium dioctyl sulfosuccinate Sodium dioctyl sulfosuccinate (AOT) 444.56 g/mol Sigma- 577-11-7 Aldrich®, USA Adenosine Adenosine triphosphate 507.18 g/mol Antai Fine Chemical Technology, China 56-65-5 triphosphate (ATP) Ammonium xylenesulfonate Ammonium xylenesulfonate 203.36 g/mol Stepan, USA 26447-10-9 Carbamide Urea 60.06 g/mol Chen Slunuel Chemicals, Israel 57-13-6 Polar carrier Propylene glycol Propylene glycol 76.09 g/mol Chen Shrnuel Chemicals, Israel 57-55-6 Active agents Retinol palmitate Retinal palmitate 524.86 g/mol Xiamen 79-81-2 Kingdomway Vitamin, China Low molecular weight sodium hyaluronate LMW HA 3 kDa Xi' an Lyphar Biotech, China 9067-32-7 Equipment Cryo-TEM: Transmission Electron Microscope (TEM), Tabs 200C by Thermo Fisher ScientificTM, USA, with a Lacey grid DSC: Differential Scanning Calorimeter DSC Q2000 (TA Instruments, USA) 5 Oven: DF0-240, by MRC, Israel Particle Size Analyzer (Dynamic Light Scattering): Zen 3600 Zetasizer (by Malvern Instruments®, United Kingdom) Sonicator: VCX 750, by Sonics & Materials, USA Thermo-rheometer: Thermo Scientific (Germany) Haake Mars III, with a C20/1° spindle, a gap of 0.052 mm, and a shear rate of 10 sec-I.

Example 1: Screening of non-volatile liquids adapted to plasticize nolvcaprolactone In the present study, various candidates for non-volatile liquids (also referred to as plasticizers agents) were tested for their suitability to plasticize a water-insoluble biodegradable compound (WIBC), and specifically, a water-insoluble biodegradable polymer (WIBP).

Each one of the various liquids was incubated for 1 hour at 80°C at a weight per weight ratio of 1:1 with PCL having a molecular weight of 14 kDa (PCL-14), namely 2 g of a nonvolatile liquid were added to 2 g of PCL-14 in a glass vial, and the sealed vials were placed in an oven, pre-heated to the plasticizing temperature. Following incubation, the contents of the vials were mixed by hand for about 30 seconds, until clear solutions were obtained. The samples of plasticized polymers were allowed to cool down overnight (Le., at least 12 hours) at room temperature so as to solidify. None of the liquids so tested displayed leaching out of the plasticized PCL-14, suggesting that they might be used satisfactorily at even higher weight per weight ratio.

Solid samples were then transferred to a rheometer where their viscosity was measured as a function of temperature between 20°C and 80°C at a ramping up temperature of 10°C/min. A reference made of unplasticized PCL-14 was included in the study, this control displaying a viscosity gradually decreasing with raising temperature from about 2x105 mPa.s (as measured at 50°C) to about 2x104 mPa.s (as measured at 80°C). For comparison, unplasticized PCL having higher molecular weights, PCL-37, PCL-45 and PCL-80 to be later detailed, provided viscosities of up to about 6.2x106 mPa.s, as measured at 50°C within the range of ramping up temperatures.

In additional measurements of viscosities in this range of temperatures for samples similarly prepared at a 1:1 weight ratio, the following non-volatile liquids were found to decrease viscosity. In the case of PCL-14, all provided for a second viscosity of less than 104 mPa. s (as measured at 50°C) as compared to the first viscosity of 2x105 mPa s for this WIBC, hence affording a decrease of at least 1.5 log. These non-volatile liquids included caprylic acid, dicaprylyl carbonate, Cu-Cis alkyl benzoate, triethyl citrate, citronellol, cyclohexane-carboxylic acid, dibutyl adipate, hinokitiol, linalool, menthol, propylene carbonate, terpinol, tert-butyl acetate, and thymol, available for instance from Sigma-Aldrich, BASF®, or Phoenix Chemical.

Based on the above-screening results, a first pair of WIBP and non-volatile liquid, namely a PCL having a molecular weight of about 14 kDa (PCL-14) and dibutyl adipate, was selected. Additional combinations of WIBCs and non-volatile liquids were similarly tested and found adapted for the preparation of nano-elements that can be combined with active agents, as suited for pharmaceutical compositions.

Example 2: Nano-suspensions of WIBCs in an aqueous polar phase An aqueous solution containing a surfactant mixture (comprising an emulsifier and hydrotropes) was prepared as follows: 6.6 g of distilled water, 0.3 g of ammonium xylenesulfonate, 0.1 g of adenosine triphosphate and 1 g of vitamin E TPGS were placed in a 20 ml glass vial and sonicated for 10 minutes (at 40% power, operated in pulses of 7 seconds, followed by 1 second breaks), until a clear aqueous solution intended to serve as liquid polar phase for the nano-elements of WIBC was obtained.

A WIBC premix was prepared as follows: in a separate 20 ml glass vial, 3 g of PCL-14 having a native melting temperature of about 62°C (as determined by DSC), were combined with 7 g of Cetiol® B, and the vial was placed in an oven at a temperature of 70°C-80°C for 1 hour until the PCL-14 was completely melted. The vial was then mixed by hand for about 30 seconds, until a clear, homogenized solution of 30 wt.% melted PCL plasticized by 70 wt.% Cetiol® B was obtained. The melting temperature of the plasticized polymer was then determined by DSC, and was found to be about 50°C, plasticizing with Cetiol® B having effectively reduced the Tm of the polymer by more than 10°C.

2 g of the WIBC premix containing the melted solution of plasticized polymer were added 25 to the vial containing the 8 g of aqueous solution including the surfactants, and sonicated for 20 minutes (as previously described), at a shearing temperature of about 70°C, whereby a nano-emulsion containing nano-droplets of liquid polymer in an aqueous solution was obtained.

This composition is reported in Table 2A as Composition 2.1. Additional compositions were prepared according to similar procedures, each composition containing different components in different amounts, and prepared under different conditions, as specified in Tables 2A-2E. Sonication, when performed, was done as described above. The values reported in the table correspond to the concentration of each component in weight percent (wt.%) by total weight of the composition, except for the values in the WIBC premix section, which correspond to the weight percentage of each component in that particular premix. The nano-emulsions so produced were allowed to passively cool down to room temperature for 1 hour, allowing for the nano-droplet to relatively solidify and the formation of a nano-dispersion. The size of the nano-particles so produced was measured by Dynamic Light Scattering (DLS) on samples of the compositions, diluted to 1:100 in water, and the measured median diameter per volume (Dv50) and per number (DN50), as well as polydispersity indices (PDI), are also presented in the tables below.

Table 2A

Component Composition 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 WIBC premix PCL-14 30 30 30 20 20 20 20 20 Cetiol® B 70 70 50 60 60 60 60 60 Tefose® 63 20 Olivatis® 12C 20 20 Olivatis® 18C 20 Olivatis® 20C 20 Olivatis® 21C 20 Premix 1 hr @80°C 2 min @80°C by sonication preparation in oven Nano-dispersion PCL-14 6 6 6 4 4 4 4 4 Cetiol® B 14 14 10 12 12 12 12 12 Vitamin E TPGS 10 15 Ammonium xylenesulfonate 3 3.6 ATP 1 Tefose® 63 4 Sodium dioctyl sulfosuccinate 4 5 5 5 5 Olivatis® 12C 4 4 Olivatis® 15C 20 Olivatis® 18C 4 Component Composition 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Olivatis® 20C 4 Olivatis® 21C 4 Propylene glycol 10 Water 66 51.4 76 75 60 75 75 75 Nano-sizing 20 min 1 mm @80°C @,70-c, Dv50 [nm] 125 39 44.3 125 109 108 130 136 DN50 [nm] 54 54.1 23.5 51.5 68.1 59 43.2 62.3 PDI 0.403 0.196 0.340 N/A 0.259 N/A 0.309 N/A

Table 2B

Component Composition 2.9 2.10 2.11 2.12 2.13 2.14 WIBC premix PCL-14 20 30 30 20 20 20 Cetiol® B 60 50 50 60 60 60 Tefose® 63 20 20 20 Ascorbyl plamitate 20 Nikkol Decaglyn 5-0V 20 Nikkol Decaglyn 5-ISV 20 Premix 2 mm @80°C by 4 mm @80°C by sonication preparation sonication Nano-dispersion PCL-14 4 6 6 4 4 4 Cetiol® B 12 10 10 12 12 12 Tefose® 63 4 4 4 Sodium dioctyl sulfosuccinate 20 4 4 Ascorbyl plamitate 4 Nikkol Decaglyn 5-0V 4 Component Composition 2.9 2.10 2.11 2.12 2.13 2.14 Nikkol Decaglyn 5-ISV 4 Texapon® SB 3 KC 5 Miconate DLS(P) 5 Miconate LES(B) 5 Olivatis® 21C Water 60 76 76 75 75 75 Nano-sizing 1 min @80°C Dv50 Inm] 116 75.1 64 105 164 85.9 Dr150 hint] 536 42.2 36.1 32.1 33.7 22.3 PDI 0.273 0.350 0.242 0.389 0.368 0.311

Table 2C

Component Composition 2.15 2.16 2.18 2.19 2.20 2.21 2.22 2.23 WIBC premix PCL-14 20 20 20 20 20 30 20 70 Celia® B 60 60 60 60 60 40 60 30 Tefose® 63 10 20 20 20 13.3 20 13.3 Olivatis® 21C 10 Labratil® M 1944 CS 6.7 10 6.7 Premix 1 min @80°C by sonication 4 min preparation @80°C by sonication Nano-dispersion PCL-14 4 4 4 4 4 6 4 28 Cetiol® B 12 12 12 12 12 8 12 12 Tefose® 63 2 4 4 4 2.7 4 2.7 Sodium dioctyl sulfosuccinate 1 1.3 1 1.3 1.3 1 Olivatis® 15C 19 18.7 Olivatis® 21C 2 Component Composition 2.15 2.16 2.18 2.19 2.20 2.21 2.22 2.23 Olivoil® glutamate 20 19 18.7 18.7 18 Labrafile M 1944 CS 1.3 2 1.3 Urea 1 Vitamin E TPGS 15 Ammonium xylenesulfonate 25 Water 60 60 60 60 60 60 60 20 Nano-sizing 1 min @80°C 2 min @80°C Dv50 [nut] 118 86.9 136 89.6 67.7 37.7 77.1 N/A IMO [mu] 71.5 50.9 41.2 55.6 43.3 34.2 46.9 109 PDI 0.176 0.277 0.429 0.249 0.190 0.220 0.232 N/A Additional compositions were similarly prepared, in which PCL-14 was replaced by various WIBPs, such as polylactic acid and polycaprolactone of higher molecular weights, specifically, 25 IcDa, 37 IcDa, 45 kDa and 80 lcDa. A non-polymeric WIBC, namely, Coenzyme Q10, was also used, without any plasticizing. These compositions are reported in Table 2D, as previously described.

Table 211

Component Composition 2.24 2.25 2.26 2.27 2.28 2.29 2.30 2.31 WIBC premix PLA 10 PCL-25 20 20 PCL-37 30 PCL-45 10 PCL-80 20 30 Coenzyme Q10 50 Cetiole B 70 70 60 60 60 40 40 Tefose® 63 20 20 20 20 20 20 20 50 Component Composition 2.24 2.25 2.26 2.27 2.28 2.29 2.30 2.31 Labrafil® M 1944 CS 10 10 Premix 4 min @80°C by sonication 1 mm @80°C by sonication 12 min preparation @70°C in oven Nano-dispersion PLA 1 PCL-25 4 4 PCL-37 6 PCL-45 2 PCL-80 4 6 Coenzyme Q10 2.5 Cetiol® B 7 14 12 12 12 8 8 Tefose® 63 2 4 4 4 4 4 4 2.5 Sodium dioctyl sulfosuccinate 5 5 1.3 1.3 1.3 Cola®Det EQ-154 5 Olivatis® 15C 18.7 Olivoil® glutamate 20 18.7 18.7 20 Labrafil® M 1944 CS 2 2 Water 85 75 75 75 60 60 60 75 Nano-sizing 1 min @80°C Dv50 [nm] 121 157 106 124 74.2 35.1 64.8 61.3 Dsr50 [nm] 38.2 34.5 33.6 101 35.8 18.2 49.1 45.9 PDI 0.224 0.262 0.371 0.048 0.239 0.214 0.156 0.595 More compositions were prepared using other non-volatile liquids instead of Cetiol® B, namely, Pelemol® 256 and Cetiol® CC. These compositions are reported in Table 2E, as previously described.

Table 2E

Component Composition 2.32 2.33 WIBC premix PCL-14 10 10 Pelemol® 256 60 Cetiol® CC 60 Olivatis® 21C 30 Vitamin E TPGS 30 Premix preparation 1 mm @80°C by sonication Nano-dispersion PCL-14 1 1 Pelemol® 256 6 Cetiol® CC 6 Olivatis® 21C 3 Vitamin E TPGS 3 Olivoil® glutamate 20 20 Water 70 70 Nano-sizing 1 min @80°C Dv50 [nm] 86.4 125 DN50 [nm] 54.8 55.5 PM 0.245 0.358 As can be seen in Tables 2A-2E, the present method is suitable to prepare nano-suspensions of nano-elements containing a WIBC, the nano-elements having Dv50 and Dr.r50 not exceeding 200 rim, these values being even lower than 100 rim for some of the compositions above reported. The PDI of the populations of nano-particles was at most about 0.4.

Samples corresponding to the above-described premixes were additionally tested for their viscosity at the end of the mixing step, when the WIBCs were at least homogeneously blended with the polar-carrier-insoluble materials, and in most case plasticized by the non-volatile liquids if present. Viscosity was determined as previously described at a shear rate of 10 secl over a range of temperatures between 20°C and 80°C, and for all samples so tested the viscosity as measured at 50°C was typically found to be of less than 106 mPa-s, being generally between 103 mPa-s and 105 mPa-s, often not exceeding 5x104 mPa-s, and many samples even having a viscosity of less 104 mPa-s.

Example 3: Nano-suspension of polycaprolactone including a polar-carrier-insoluble active agent In the present example, an active agent was added to the WIBC. Water-insoluble retinol palmitate having a molecular weight of about 525 g/mol was used to exemplify the incorporation of a polar-carrier-insoluble active agent into nano-elements including the WIBC. Retinal palmitate can also be considered as an exemplary vitamin, as may be suited for the preparation of nutraceuticals.

A WIBC/retinol premix was prepared in a 20 ml glass vial by combining 2 g of PCL-14, 1 g of retinol palmitate, 1 g of Olivatis® 12C as a surfactant and 6 g of Cetiol® B as a plasticizing non-volatile liquid. The vial was sonicated for 2 minutes (as previously described) at a temperature of about 80°C, to obtain a clear homogenized solution of plasticized WIBC. The WIBC/retinol premix was maintained in an oven at a temperature of 80°C until mixed with the aqueous phase.

In a separate 20 ml glass vial, 7.5 g of distilled water and 0.5 g of sodium dioctyl sulfosuccinate, as an additional surfactant being a hydrotrope, were placed and sonicated for 1 minute at a temperature of about 60°C, until a clear aqueous solution intended to serve as liquid polar phase was obtained.

2 g of the hot WIBC/retinol premix were then added to the vial containing the 8 g of aqueous solution and sonicated for 1 minute at a shearing temperature of about 70-80°C, whereby a nano-emulsion containing nano-droplets of liquid PCL and retinol palmitate were dispersed in an aqueous polar phase.

This composition is reported in Table 3 as Composition 3.1. Other compositions were prepared according to similar procedures, containing different components in different amounts, as specified in the table. The values reported in the table correspond to the concentration of each component in weight percent (wt.%) by total weight of the composition, except for the values in the WIBC/retinol premix section, which correspond to the weight percentage of each component in that particular premix. The nano-emulsions so produced were allowed to passively cool down to room temperature for 1 hour, allowing for the nano-droplet to relatively solidify and the formation of a nano-dispersion. The size and PDI values of the nano-particles so produced, measured by DLS as previously described, are also presented in Table 3.

Table 3

Composition 3.1 3.2 3.3 3.4 3.5 PCL/retinol premix PCL 20 33 20 20 20 Cetiols B 60 47 60 60 60 Tefose® 63 13.45 10 Olivatis® 12C 10 Olivatiss 21C 5 Retinol palmitate 20 6.55 20 10 5 Premix preparation 2 min @80°C by sonication 1 min @80°C by sonication Nano-dispersion PCL 6 9.9 4 4 4 Cetiol® B 18 14.1 12 12 12 Vitamin E TPGS 10 Ammonium xylenesulfonate 20 Tefose® 63 4 2 Sodium dioctyl sulfosuccinate 5 5 5 2 Olivatis® 12C 2 Olivatis® 15C 18 Olivatis® 20C 1 Retinol palmitate 6 2 4 2 1 Water 40 65 75 75 60 Nano-sizing 2 min @80°C 1 rrin @80°C Dv50 [nm] 171 58.6 138 82.1 96.3 DN50 [nm] 78.5 21 68.9 34.1 60.4 PDI 0.27 0.179 0.259 0.314 0.184 As can be seen in Table 3, the present method is suitable to prepare nano-suspensions of 5 nano-elements containing a WIBC and a carrier-insoluble active agent, the nano-elements having Dv50 and DN50 not exceeding 200 nm, these values being even lower than 100 rim for some of the compositions above reported. The PDI of the populations of nano-particles was at most about 0.3.

Example 4: Nano-suspensions of polvcaprolactone in a liquid polar phase including a 5 polar-carrier-soluble active agent An aqueous solution containing a surfactant mixture (comprising an emulsifier and a hydrotrope) was prepared as follows: 4.4 g of distilled water, 0.6 g of ammonium xylenesulfonate and 1 g of vitamin E TPGS were placed in a 20 ml glass vial, and sonicated for 10 minutes (as previously described), until a clear aqueous solution including the surfactants and intended to serve as liquid polar phase was obtained.

In a separate 20 ml glass vial, a WIBC premix was prepared as follows: 3 g of PCL-14 and 7 g of Cetiol® B were combined, and the vial was placed in an oven at a temperature of 80°C for 1 hour until the PCL was plasticized and completely melted. The vial was then mixed by hand for about 30 seconds, until a clear, homogenized solution of 30 wt.% melted PCL, plasticized with 70 wt.% Cetiol® B was obtained 2 g of the melted solution of plasticized polymer were added to the vial containing 6 g of the aqueous solution with the surfactants and sonicated for 20 minutes (as described above) at a shearing temperature of about 70°C, whereby a nano-emulsion containing nano-droplets of liquid polymer in an aqueous polar phase was obtained.

The nano-emulsion was allowed to passively cool down to room temperature for a cooling period of 1 hour, at which time 1 g of propylene glycol was added, and the contents of the vial were mixed by hand for 10 seconds. Subsequently, 1 g of LMW hyaluronic acid, as the polarcarrier-soluble active agent, was added, and the vial contents were again mixed by hand for about 10 seconds until complete dissolution of the HA in the liquid polar phase.

This composition is reported in Table 4 as Composition 4.1. An additional composition was similarly prepared, containing different components in different amounts. The values reported in the table correspond to the concentration of each ingredient in weight percent (wt.%) by total weight of the composition, except for the values in the WIBC premix section, which correspond to the weight percentage of each component in that particular premix. The size and PDI values of the nano-particles so produced, as measured by DLS as previously described, are also presented in Table 4.

Table 4

Component Composition 4.1 4.2 4.3 WIBC premix PCL-14 30 30 30 Cetiol® B 70 70 40 Tefose® 63 20 Labrafil® M 1944 CS 10 Premix preparation 10 min @80°C by sonication 5 min @80°C by sonication Nano-dispersion PCL-14 6 5 6 Cetiol® B 14 11.7 8 Vitamin E TPGS 10 Kolliphor® P 407 8.3 Ammonium xylenesulfonate 6 16.7 ATP 8.3 Tefose® 63 4 Labrafil® M 1944 CS 2 Sodium dioctyl sulfosuccinate 1.3 Olivoil® glutamate 18.7 Propylene glycol 10 4.2 Water 44 37.5 Nano-sizing 20 min @70°C by sonication 1 min @80°C by sonication Cooling period 1 hour 12 hours LMW HA 10 8.3 0.1 Dv50 [nm] 56.3 141 74.9 DN50 [nm] 41 96.7 52.3 PD! 0.195 0.212 0.210 As can be seen in Table 4, the present method is suitable to prepare nano-suspensions of nano-elements containing a WIBC and a carrier-soluble active agent, the nano-elements having Dv50 and DN50 not exceeding 200 nm, the PDI of the populations of nano-particles being of at most about 0.2.

Representative results of particle size distribution in a sample of Composition 4.1, showing the percentage (per volume) of nano-particles having hydrodynamic diameters in the range of 10-1,000 nm, are presented in Figure 2.

The size of the nano-particles of Composition 4.1 was further confirmed by microscopic TEM measurement of an image taken on a cryogenic cut of the nano-dispersion, the frozen nano-particles observed in the image having sizes in agreement with the measurements obtained by DLS. An exemplary image is shown in Figure 3 where the nano-particles appear on the background as darker greyish globules.

It is believed that the methods of Examples 3 and 4 can be combined, when a nano-dispersion is to include nano-elements of WIBC(s), the dispersion including two types of active agents, the carrier-insoluble ones being disposed within the WIBC(s) matrix in the nano-element and the carrier-soluble ones being disposed in the surrounding polar carrier.

It is appreciated that certain features of the disclosure, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the disclosure, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination or as suitable in any other described embodiment of the disclosure. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

Although the present disclosure has been described with respect to various specific embodiments presented thereof for the sake of illustration only, such specifically disclosed embodiments should not be considered limiting. Many other alternatives, modifications and variations of such embodiments will occur to those skilled in the art based upon Applicant's disclosure herein. Accordingly, it is intended to embrace all such alternatives, modifications and variations and to be bound only by the spirit and scope of the disclosure and any change which come within their meaning and range of equivalency.

In the description and claims of the present disclosure, each of the verbs "comprise", "include" and "have", and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of features, members, steps, components, elements or parts of the subject or subjects of the verb. Yet, it is contemplated that the compositions of the present teachings also consist essentially of, or consist of, the recited components, and that the methods of the present teachings also consist essentially of, or consist of, the recited process steps.

As used herein, the singular form "a", "an" and "the" include plural references and mean "at least one" or "one or more" unless the context clearly dictates otherwise. At least one of A and B is intended to mean either A or B, and may mean, in some embodiments, A and B. A "material" that may be present in the composition alone or in combination with other materials of the same type can be referred to as "material(s)"; WIBC(s), WIBP(s), polar carrier(s), non-volatile liquid(s), surfactant(s), active agent(s) and the like, respectively indicating that at least one WIBC, at least one WIBP, at least one polar carrier, at least one non-volatile liquid, at least one surfactant, at least one active agent, and so on, can be used in the present methods or be included in the composition or satisfy the recited parameter or suitable range thereof Unless otherwise stated, the use of the expression "and/or" between the last two members of a list of options for selection indicates that a selection of one or more of the listed options is appropriate and may be made.

Unless otherwise stated, when the outer bounds of a range with respect to a feature of an embodiment of the present technology are noted in the disclosure, it should be understood that 20 in the embodiment, the possible values of the feature may include the noted outer bounds as well as values in between the noted outer bounds.

As used herein, unless otherwise stated, adjectives such as "substantially", "approximately" and "about" that modify a condition or relationship characteristic of a feature or features of an embodiment of the present technology, are to be understood to mean that the condition or characteristic is defined to within tolerances that are acceptable for operation of the embodiment for an application for which it is intended, or within variations expected from the measurement being performed and/or from the measuring instrument being used. When the term "about" and "approximately" precedes a numerical value, it is intended to indicate +115%, or +/-10%, or even only +/-5%, and in some instances the precise value. Furthermore, unless otherwise stated, the terms (e.g., numbers) used in this disclosure, even without such adjectives, should be construed as having tolerances which may depart from the precise meaning of the relevant term but would enable the invention or the relevant portion thereof to operate and function as described, and as understood by a person skilled in the art.

While this disclosure has been described in terms of certain embodiments and generally associated methods, alterations and permutations of the embodiments and methods will be apparent to those skilled in the art. The present disclosure is to be understood as not limited by the specific embodiments described herein.

Certain marks referenced herein may be common law or registered trademarks of third parties. Use of these marks is by way of example and shall not be construed as descriptive or limit the scope of this disclosure to material associated only with such marks.

Claims

CLAIMS1. A pharmaceutical composition comprising nano-elements containing: a) a water-insoluble biodegradable compound (WIBC) having a molecular weight of 0.6 kiloDalton (Ma) or more; and b) a polar-carrier-insoluble active agent disposed therein; wherein the nano-elements i) are dispersible in a polar carrier; ii) have an average diameter Dv50 of 200 nm or less; and iii) contain less than 0.5 wt.% of a volatile organic compound (VOC) by weight of the nano-elements.
2. The pharmaceutical composition as claimed in claim 1, wherein the WIBC is characterized by at least one, at least two, or at least three of the following properties: i. the WIBC is insoluble in the polar carrier; the WIBC has at least one of a first melting temperature (Tm), a first softening temperature (Ts) and a first glass transition temperature (Tg) of at most 300°C, at most 250°C, at most 200°C, at most 180°C, at most 150°C, or at most 120°C; iii. the WIBC has a first Tm or Ti of at least 20°C, at least 30°C, at least 40°C, at least 50°C, or at least 60°C; iv. the WIBC has a first Tg of -75°C or more, -50°C or more, -25°C or more, 0°C or more, 25°C or more, or 50°C or more; v. the WIBC has at least one of a first Tm, Ts and Tg between 20°C and 300°C, between 20°C and 250°C, between 20°C and 200°C, between 30°C and 180°C, between 40°C arid 180°C, or between 50°C and 150°C; vi. the WIBC has a molecular weight of 0.7 kDa or more, 0.8 kDa or more, 0.9 kDa or more, 1 kDa or more, 2 kDa or more, or 5 kDa or more; vii. the WIBC has a molecular weight of 500 kDa or less, 300 kDa or less, 200 kDa or less, 100 kDa or less, 80 kDa or less, 50 kDa or less, 25 kDa or less, or 15 kDa or less; and viii. the WIBC has a molecular weight between 0.6 kDa and 500 Ma, between 0.7 kDa and 300 kDa, between 0.8 kDa and 200 lcDa, between 1 kDa and 100 kDa, or between 2 kDa and 80 kDa.
3. The pharmaceutical composition as claimed in claim 1 or claim 2, wherein the WIBC is selected from: (I) a polymer selected from a group of polymer families comprising aliphatic polyesters, polyhydroxy-alkanoates, poly(alkene dicarboxylates), polycarbonates, aliphatic-aromatic copolyesters, isomers thereof, copolymers thereof and combinations thereof; and (II) a quinone selected from a group including Coenzyme Q10.
4. The pharmaceutical composition as claimed in any one of claim I to claim 3, wherein the polar carrier includes at least one polar material selected from a group consisting of water, glycols and glycerols.
5. The pharmaceutical composition as claimed in any one of claim 1 to claim 4, wherein the WIBC is plasticized by a non-volatile liquid.
6. The pharmaceutical composition as claimed in claim 5, wherein the non-volatile liquid is selected from a group comprising monofunctional or polyfunctional aliphatic esters, fatty esters, cyclic organic esters, fatty acids, terpenes, aromatic alcohols, aromatic ethers, aldehydes and combinations thereof.
7. The pharmaceutical composition as claimed in any one of claim 1 to claim 6, further comprising at least one surfactant being an emulsifier or an hydrotrope.
8. The pharmaceutical composition as claimed in any one of claim 1 to claim 7, wherein the nano-elements contain between 0.001 wt.% and 0.5 wt.%, between 0.002 wt.% and 0.4 wt.%, between 0.003 wt.% and 0.3 wt.%, between 0.004 wt.% and 0.2 wt.%, between 0.005 wt.% and 0.1 wt.%, between 0.001 wt.% and 009 wt.%, between 0.002 wt.% and 0.08 wt.%, between 0.003 wt.% and 0.07 wt.%, between 0.004 wt.% and 0.06 wt.%, or between 0.005 wt.% and 0.05 wt.% of a VOC by weight of the nano-elements.
9. The pharmaceutical composition as claimed in any one of claim 1 to claim 8, wherein the polar-carrier-insoluble active agent has a molecular weight of up to 500 kDa, up to 400 kDa, up to 300 kDa, up to 200 kDa, up to100 kDa, up to 50 kDa, up to 40 kDa, up to 30 kDa, up to 20 kDa, up to 10 kDa, or up to 5 kDa.
10. A method for preparing nano-elements adapted for a pharmaceutical composition, the nano-elements consisting of a water-insoluble biodegradable compound (WIBC) and a polarcarrier-insoluble active agent, the method comprising the steps of: a) providing a WIBC, wherein: i. the WIBC has a molecular weight of at least 0.6 kDa; ii. the WIBC has at least one of a first melting temperature (Tm), a first softening temperature (Ts), and a first glass transition temperature (Tg) of 300°C or less; and iii. the WIBC has a first viscosity optionally higher than 107 mPa.s, as measured at 50°C and a shear rate of 10 see; b) providing a polar-carrier-insoluble active agent; c) mixing the WIBC and the polar-carrier-insoluble active agent optionally with a nonvolatile liquid miscible therewith, the mixing being at a mixing temperature equal to or higher than at least one of the first Tm, Ts, and Tg of the WIBC, whereby a homogeneous mixture of an optionally plasticized WIBC and polar-carrier-insoluble active agent is formed, the optionally plasticized WIBC having a second Tm, Ts, or Tg lower than the respective first Tm, Ts, or Tg, and a second viscosity lower than the first viscosity, at least one of the first and the second viscosity being of 107 mPa.s or less, as measured at 50°C and a shear rate of 10 sec-1; d) combining a polar carrier with the mixture containing the polar-carrier-insoluble active agent and the WIBC, or the optionally plasticized WIBC; and e) nano-sizing the combination of step d) by applying shear at a shearing temperature equal to or higher than at least one of the first Tm, l's, and Tg of the WIBC or at least one of the second Tm, Ts, and Tg of the optionally plasticized WIBC, so as to obtain a nano-suspension, whereby nano-elements comprising (optionally plasticized) WIBC and the polar-carrier-insoluble active agent are dispersed in the polar carrier, the nano-elements being characterized by: i) having an average diameter Dv50 of 200 nm or less; and ii) containing less than 0 5 wt.% of a volatile organic compound (VOC) by weight of the nano-elements.
11. The method as claimed in claim 10, wherein the WIBC is further characterized by at least one, at least two, or at least three of the following properties: i. the WIBC is insoluble in the polar carrier; ii. the WIBC has at least one of a first Tm, Ts, or Tg of at most 250°C, at most 200°C, at most 180°C, at most 150°C, or at most 120°C; iii. the WIBC has a first Tm or 7's of at least 20°C, at least 30°C, at least 40°C, at least 50°C, or at least 60°C; iv. the WIBC has a first Tg of -75°C or more, -50°C or more, -25°C or more, 0°C or more, 25°C or more, or 50°C or more; v. the WIBC has at least one of a first Tm, Ts and Tg between 20°C and 300°C, between 20°C and 250°C, between 20°C and 200°C, between 30°C and 180°C, between 40°C and 180°C, or between 50°C and 150°C; vi. the WIBC has a molecular weight of 0.7 kDa or more, 0.8 kDa or more, 0.9 kDa or more, 1 kDa or more, 2 kDa or more, or 5 kDa or more; vii. the WIBC has a molecular weight of 500 kDa or less, 300 kDa or less, 200 kDa or less, 100 kDa or less, 80 kDa or less, 50 kDa or less, 25 IcDa or less, or 15 kDa or less; and viii. the WIBC has a molecular weight between 0.6 kDa and 500 kDa, between 0.7 kDa and 300 kDa, between 0.8 kDa and 200 kDa, between 1 kDa and 100 kDa or between 5 kDa and 80 kDa.
12. The method as claimed in claim 10 or claim 11, wherein a non-volatile liquid is provided in step c), the non-volatile liquid being mixed with the WIBC and the polar-carrier insoluble active agent at a weight ratio of at least 1:200, at least 1:20, at least 1:5, at least 1:1, at least 2:1, or at least 3:1, by combined weight of the WIBC and the active agent.
13. The method as claimed in any one of claim 10 to claim 12, wherein at least one of the second Tm, Ts, or Tg of the homogeneous mixture of an optionally plasticized WIBC with the polar-carrier-insoluble active agent is in a range from 0°C to 290°C, 10°C to 250°C, from 20°C to 200°C, from 30°C to 190°C, from 40°C to 180°C, or from 50°C to 170°C.
14. The method as claimed in any one of claim 10 to claim 13, wherein at least one of the first viscosity of the WIBC and the second viscosity of the plasticized WIBC, when a nonvolatile liquid is provided in step c), is 5x106 mPa-s or less, 106 mPa-s or less, 5x103 mPa-s or less, 105 mPa-s or less, 104 mPa-s or less, or 103 mPa-s or less, as measured at 50°C and a shear rate of 10 see.
15. The method as claimed in any one of claim 10 to claim 14, wherein the polar carrier has a boiling temperature Tbc at a pressure of nano-sizing and the optional non-volatile liquid has a boiling temperature Tbi at a pressure of mixing, the temperature of nano-sizing being lower than Tb, and the temperature of optional mixing being lower than Tbi.
16. The method as claimed in any one of claim 10 to claim 15, wherein the nano-elements contain between 0.001 wt.% and 0.5 wt.%, between 0.002 wt.% and 0.4 wt.%, between 0.003 wt.% and 0.3 wt.%, between 0.004 wt.% and 0.2 wt.%, between 0.005 wt.% and 0 1 wt.%, between 0.001 wt.% and 0.09 wt.%, between 0.002 wt.% and 0.08 wt.%, between 0.003 wt.% and 0.07 wt.%, between 0.004 wt.% and 0.06 wt.%, or between 0.005 wt.% and 0.05 wt.% of a VOC by weight of the nano-elements.
17. The method as claimed in any one of claim 10 to claim 16, wherein the polar-carrierinsoluble active agent has a molecular weight of up to 500 kDa, up to 400 kDa, up to 300 kDa, up to 200 kDa, up to100 kDa, up to 50 kDa, up to 40 kDa, up to 30 kDa, up to 20 kDa, up to 10 kDa, or up to 5 lcDa.
18. The method as claimed in any one of claim 10 to claim 17, further comprising isolating the nano-elements and preparing therewith a pharmaceutical composition in dry dosage form or in liquid dosage form.
19. A pharmaceutical composition comprising nano-elements containing: a) a water-insoluble biodegradable compound (W1BC) having a molecular weight of 0.6 kiloDalton (ma) or more; and b) a polar-carrier-insoluble active agent disposed therein; wherein the nano-elements i) are dispersible in a polar carrier; ii) have an average diameter Dv50 of 200 nm or less; and iii) contain less than 0.5 wt.% of a volatile organic compound (VOC) by weight of the nano-elements; wherein the pharmaceutical composition is for the diagnostic, prevention or treatment of any ailment in accordance with the active agent(s) disposed in the nano-elements, the active agents being in an amount sufficient for its efficacious diagnostic, preventive or treating use.
20. The composition for use as claimed in claim 19, wherein the pharmaceutical composition is a pharmaceutical composition as claimed in any one of claim 1 to claim 9.