The present invention relates to solid dispersions comprising Coenzyme Qio and phospholipids, to a process for their preparation and to pharmaceutical, nutraceutical and cosmetic compositions containing them.

Coenzyme Qio, also known as ubidecarenone or ubiquinone, is a lipophilic endogenous substance present in most eukaryotic cells, primarily concentrated in mitochondria. Coenzyme Qio participates to the mitochondrial oxido-reductive reactions of electron transport chain for the generation of energy, in the form of Adenosine Triphosphate (ATP). Coenzyme Qio can exist in three oxidation states: (1) the fully reduced form (ubiquinol), (2) the radical intermediate form (semiquinone), and (3) the fully oxidized form (ubiquinone). Coenzyme Qio exists in our body in all these forms and a physiological equilibrium between the oxidized and the reduced form is maintained.

Ubiquinone (CoQ)

The name ubidecarenone or ubiquinone (or ubiquinol for the reduced form) is related to the fact that Coenzyme Qio is ubiquitously distributed in the organs of the human body, but it is primarily concentrated in organs with a higher energy requirement, like heart, liver and kidney.

The name ubiquinone also refers to its quinone structure, while the number 10 is the number of isoprenyl units in its tail.

Coenzyme Qio can also be introduced in human body with the diet, even if the contribution of endogenous Coenzyme Qio to its physiological plasma levels has not been clarified. The richer sources of dietary Coenzyme Qio include meat, poultry and fish, while fruits, vegetables and eggs are limited sources of Coenzyme Qio.

As Coenzyme Qio deficiency is a rare, oral coenzyme Qio supplementation is mainly used to maintain homeostasis of the body, to promote heart health, as energy booster and also to treat different diseases like ageing, periodontal disease, impaired memory, fatigue, coronary disease, high blood pressure, immune system impairment.

Coenzyme Qio supplementation can be particularly useful for elderly people, as the tissue and plasma physiological levels of Coenzyme Qio are reported to decline with age.

Coenzyme QIO is a yellow-orange crystalline powder, with a low melting point (about 50°C).

The activity of Coenzyme Qio supplementation can be strongly limited by its poor pharmacokinetic properties and, in particular, by its very low oral bioavailability, due to the fact that Coenzyme Qio is commercialized in a totally crystalline form and it is characterized by high lipophilicity and relatively high molecular weight.

Several formulation approaches have been applied to promote CoQio bioavailability, including self-emulsifying delivery systems, inclusion in cyclodextrins, solid dispersion, lipophilic formulations, microspheres, nanoparticles, etc., but absorption of Coenzyme Qio into the systemic circulation still remains a challenge.

It has now been found that preparing a solid dispersion of Coenzyme Qio and phospholipids, in the presence of other ingredients such as cellulose derivatives (methylcellulose, hydroxypropylcellulose, hydroxypropylmethyl cellulose, microcrystalline cellulose, and the like) and/or other polymeric materials including but not limited to polyvinylpyrrolidone, polyvinyl acetate, poly (methacrylic acid, methyl methacrylate), poloxamers and the like , allows a high degree of amorphization of Coenzyme Qio, determining an increased solubility, a faster dissolution rate and hence a better oral bioavailability.

The above mentioned cellulosic derivatives and other polymeric materials can contribute to stabilize the amorphous form of Coenzyme Qio in order to avoid its re-crystallization in the less bioavailable crystalline form.

The role of phospholipids may not be limited to facilitate the dispersion of Coenzyme Qio in the gastro-intestinal fluids, but can also have the effect of enhancing the capacity of Coenzyme Qio to cross the lipid-rich biomembranes and to reach the circulation.

These solid dispersions are also characterized by suitable technological properties to be easily incorporated in different dosage forms to allow an easy administration.

The present invention relates to a solid dispersion comprising:

a) Coenzyme QIO

b) a phospholipid,

c) one or more a cellulosic derivative selected from the group consisting of carboxymethyl cellulose, methylcellulose, ethyl cellulose, hydroxypropylcellulose, hydroxyethyl cellulose, hydroxypropylmethyl cellulose, microcrystalline cellulose, cellulose acetate phthalate, hydroxypropylmethyl cellulose phthalate; and/or d) a polymeric material selected from the group consisting of polyvinylpyrrolidone, polyvinyl acetate, poly (methacrylic acid, methyl methacrylate), poloxamers, chitosan, alginates, hyaluronic acid, pectin, pullulan, cyclodextrins, starch polymers, D-alpha- tocopheryl polyethylene glycol 1000 succinate. The phospholipid may be selected from the group consisting of lecithins from soy, sunflower or egg, phosphatidyl choline, phosphatidyl serine, phosphatidyl ethanolamine, in which the acyl groups may be the same or different are mostly derived from palmitic, stearic, oleic, linoleic, linolenic acids.

In the present invention, all ratios are weight ratios.

The Coenzyme Qio /phospholipid ratio is preferably 0.2 to 2, most preferably 0.5 to 1.

The Coenzyme Qio to cellulosic derivative ratio is preferably 0.2 to 2, most preferably 0.5 to 1.

The Coenzyme Qio to polymeric material ratio is 0.2 to 10, most preferably

0.5 to 5.

The solid dispersions of the invention provide Coenzyme Qio with an increased degree of amorphization and a reduced tendency to recrystallize in a less bioavailable form. The solid dispersions have improved the technological properties facilitating the incorporation of the complex in different pharmaceutical, nutraceutical and cosmetic formulations.

The solid dispersions, according to the present invention, are prepared by a method comprising the steps of:

i) preparing a suspension of the one or more cellulosic derivative, the phospholipid and/or the polymeric material in an organic solvent;

ii) preparing a solution of coenzyme Q10 in an organic solvent;

iii) mixing the solution obtained in step ii) with the suspension obtained in step i);

iv) stirring the suspension obtained in step iii) at a temperature between 40°C and 70°C;

v) removing the solvent preferably under reduced pressure from the suspension obtained in step iv).

The organic solvent is preferably ethanol, acetone and ethyl acetate, most preferably ethyl acetate.

The obtained powder is then calibrated and eventually grinded to obtain the desired particle size distribution.

The obtained solid dispersions were analyzed for HPLC content of Coenzyme Qio, for water content and for residual solvent.

A calorimetric analysis by Differential Scanning Calorimetry (DSC) was also performed to calculate, on the basis of the reduction of the enthalpy of fusion (J/g), the degree of amorphization of Coenzyme Qio in the solid dispersion, in comparison with the totally crystalline Coenzyme Qio.

It has been found that the phospholipids dispersions disclosed in the present invention are characterized by a high level of amorphization of Coenzyme Qio. The amorphization of Coenzyme QIO combined with the positive effect of phospholipids to enhance the capacity of molecules to cross the lipid-rich biomembranes, can play a synergistic effect providing a higher oral bioavailability.

Another object of the invention are formulations for oral administration containing the solid dispersions of the invention and pharmaceutically and food acceptable materials such as an excipient, disintegrant, lubricant, binder, coating agent, colorant, absorption promoter, solubilizing agent, stabilizer, flavor, sweetener, antiseptic, preservative, antioxidant and the like.

Examples of dosage forms of the formulations of the invention include, without limitation, chewable tablets, capsules, soft gelatin capsules, hard gelatin capsules, caplets, lozenges, chewable lozenges, health bars, confections, animal feeds, cereals, cereal coatings, and combinations thereof. The preparation of the above dosage forms are well known to persons of ordinary skill in the art.

The composition for oral administration of the present invention can be used for a variety of purposes for improving the quality of life (QOL) of humans, including the prevention and treatment for various diseases, reduction of side reactions, promotion of recovery from disease and the like, and can also be used for the purpose of maintaining and promoting daily health and the like. The dosage of the composition for oral administration of the present invention is not subject to limitation, and is preferably 1 to 1200 mg per day for a human, based on the amount of Coenzyme Qio, more preferably 10 to 800 mg, and from the viewpoint of routine ingestion and onset of effects, it is particularly preferably 30 to 500 mg. The above- described daily amount can be taken at one time or in several divided portions. Duration of ingestion is not subject to limitation.

The oral bioavailability of the solid dispersion of Coenzyme Qio was evaluated in rats in comparison with Coenzyme Qio administered as crystalline powder. The preliminary results show an improved oral bioavailability of the solid dispersion of Coenzyme Qio with phospholipids in comparison with unformulated Coenzyme Qio.

EXAMPLES

Example 1 - Preparation of the solid dispersion

1.5 Kg of microcrystalline cellulose, 2.0 Kg of sunflower lecithin and 0.5 Kg of cellulose ethers (methyl cellulose and hydroxypropylmethyl cellulose) were suspended in 50 liters of ethyl acetate and refluxed for one hour. The resulting suspension was cooled to 40°C.

1 Kg of Coenzyme Qio was dissolved in 30 liters of ethyl acetate at 20-25°C in the dark. The obtained solution was filtered and added to the suspension of microcrystalline cellulose, sunflower lecithin and cellulose ethers. The obtained suspension was stirred at 40°C for about one hour.

The solvent was then removed under reduced pressure until a soft mass was obtained. The latter was dried at 50°C under vacuum for 16 hours, until a residual of Ethyl acetate lower than 5000 ppm.

The resulting solid was calibrated through a 2 mm screen to obtain a yellow- orange solid

Example 2 - Characterization of the solid dispersion; Differential Scanning Calorimetry

The solid dispersion of Coenzyme Q10 with phospholipid was analyzed by Differential Scanning Calorimetry (DSC) in comparison with crystalline Coenzyme The analyses were performed using a Mettler DSC1 System. Heat flow was recorded from 30 to 300°C with linear heating rate (10°C/min), using closed aluminium crucibles (40 μΐ volume) with a pinhole, under a 50 ml/min nitrogen flow.

About 5-10 mg of powder were used for each measurement. The thermal profiles were acquired and elaborated by a dedicated software.

The degree of amorphization of Coenzyme Qio in the solid dispersion was in the range 30-40% and it was calculated on the basis of the reduction of the enthalpy of fusion.

Example 3 - Pharmacokinetic study in rats

Pharmacokinetic parameters (T max, ^max, absolute bioavailability) were determined in rats after the oral administration of a single dose of Coenzyme Qio as crystalline powder and as solid dispersion with phospholipids.

Male Sprague-Dawley rats, weighting 300-350 g were used for the pharmacokinetic experiment. Rats were fasted 16 hours before administration with free access to water.

Coenzyme Qio as crystalline powder and as solid dispersion with phospholipids were suspended in 1% carboxymethyl cellulose water suspension and administered by intragastric gavage as a single dose of 50 mg of Coenzyme Qio/Kg.

Blood samples were collected from tail vein after 0.5 - 1.0 - 2.0 - 4.0 - 8.0 - 12.0 and 24 hours after administration.

Plasma was obtained from blood samples by centrifugation at 5.000 x g for

15 minutes and kept frozen (-20°C) until analysis. After protein sedimentation, Coenzyme Qio was extracted by plasma samples with n-hexane; the extraction step with hexane was repeated for three times. The hexane phases, separated by centrifugation, were collected and the solvent was removed by evaporation under nitrogen. The residue was dissolved in 2-propanol for HPLC/MS analysis at 275 nm, using internal standard method for Coenzyme Qio quantification.

The following pharmacokinetic parameters were calculated:

Example 4 - Formulations containing the solid dispersion of Coenzyme C o with phospholipid (film-coated tablets)

Coenzyme Qio solid dispersion 400.0 mg

Microcrystalline cellulose 200.0 mg

Dicalcium phosphate anhydrous 146.0 mg

Sodium croscarmellose 30.0 mg

Silicon dioxide 8.0 mg

Talc 8.0 mg

Magnesium stearate 8.0 mg

Film-coating 20.0 mg

Example 5 - Formulation containing the solid dispersion of Coenzyme C o with phospholipids (soft gelatin capsules)

Coenzyme Qio solid dispersion 250.0 mg

Flaxseed oil 384.0 mg

Glyceryl monostearate 10.0 mg

Lecithin 6.0 mg