The invention relates to an emulsion and a use of the emulsion as a parenteral preparation.

The triglyceride 2-eicosapentaenoyl-l,3-dioctanoyl glycerol is described in US 4,407,052 and S. E. Boustani et al. , Lipids, 22, 711-14 (1987). Also, an emulsion for enteral use of this triglyceride is described. Eicosapentaenoic acid is abbreviated EPA.

As the above triglyceride is important as a nutrient, especially ^" for diseased humans, there is a need for an emulsion of 2-eicosapentaenoyl-l,3-dioctanoyl glycerol, which can be used for parenteral nutrition, and which exhibits a better bioavailability than hitherto known parenteral emulsions used as a source for EPA. A very important clinical aspect in regard to the bioavailability is the slower metabolism in comparison to emulsions containing MCT, which are known to cause metabolic acidosis when infused intravenously.

The emulsion according to the invention with an aqueous continuous phase and containing as the discontinous phase the triglyceride 2-eicosapentaenoyl-l,3-dioctanoyl glycerol, is characterized by the fact that it is formulated for parenteral use. Any worker skilled in the art will know in principle how to compose such formulation. Surprisingly it has been found that the emulsion according to the invention exhibits a better bioavailability than hitherto known parenteral emulsions used as a source for EPA. Moreover, the above-mentioned triglycerides turn out, surprisingly, to be very efficient sources of energy in when applied in parenteral nutrition - the EPA acid moiety of the triglycerides being in an optimal position in the molecule in respect to their cleavage by lipoprotein lipase.

Surprisingly, the above triglycerides appear to exhibit physical properties which allow facile formulation of the compounds in liquid products as well as in powdered products exhibiting excellent wetability properties. In the

liquid form the products of the invention possess excellent stabilities making sterilization of e.g. parenteral products containing the above-mentioned triglycerides reliable, easy and safe. The above-mentioned triglycerides are advantageously applied in such emulsions due to their fast conversion by lipoprotein lipase and endothelial lipase and the consequential avoidance of the discomfort and side effects of lipolipaedemia. Arachidonic acid applied in above triglycerides is thus cleared quickly and efficiently thereby providing the essential fatty acid concomitantly with short chain acids useful as energy substrates.

The use of the above-mentioned triglycerides in parenteral nutritional products is further particularly advantageous since the relatively high polarity of the triglycerides favour the stability of their emulsions which are subjected to severe heat treatments during their manufacturing. Use of such emulsion is particularly advantageous for nutrition of severely ill patients e.g. post-operatively.

Another advantage of the products of the invention has to do with the stability of the EPA towards oxidation and thus the avoidance of problems associated with oxidation of polyunsaturated fatty acids. It thus turns out that products according to the invention allows preparation of EPA containing lipids with an improved quality of EPA as compared to other sources of the essential fatty acid. Detrimental processes of polyunsaturated fats and oils leading to negative nutritional forms are thus commonly associated with gastric and intestinal problems due to oxidation and polymerisation products of the polyunsaturated fatty acid. Such oxidized forms of EPA can interfere with nitrogen uptake by interacting with sensitive amino acids. These highly undesired effects are diminished or even avoided by applying triglycerides according to the invention.

A preferred embodiment of the emulsion according to the invention is characterized by the fact that the average

diameter of the triglyceride globules is between 5 and 1000 nm, and that less than 5% of the triglyceride globules exhibits a diameter above 5000 nm. This emulsion is well suited as a parenteral emulsion and shows a good bioavailability.

A preferred embodiment of the emulsion according to the invention is characterized by the fact that the average diameter of the triglyceride globules is between 5 and 1000 nm, that less than 5% of the triglyceride globules exhibits a diameter above 5000 nm, that the amount of the triglyceride in relation to the amount of the entire emulsion is between 2 and 30% by weight, and that the emulsion contains glycerol to isotonicity and 0.2 - 10% by weight of an emulsifier. This emulsion is very well suited as a parenteral emulsion and shows a superior absorption ability. A preferred emulsifier is a phospholipid.

A preferred embodiment of the emulsion according to the invention is characterized by the fact that the triglyceride has a purity of at least 10%, preferably at least 30%, more preferably at least 50%, even more preferably at least 75%, and most preferably at least 90%. The higher the purity of the triglyceride, the more efficient the absorption of the triglyceride in the intestines.

Also the invention comprises a use of the emulsion according to the invention as a parenteral preparation.

EXAMPLE 1

A parenteral feeding product was prepared according to the following formula:

Composition for 1000 ml I Lipid 100.0 g

II Egg yolk phospholipids (Lipoid E80) 12.0 g

III Glycerol 22.5 g

IV Water for injection to 1000 ml

Production Procedure

II was dispersed in 500 ml of IV by a high shear mixer (Ultra turrax) followed by the addition of I and III. Fianlly water (IV) was added to a total volume of 1000 ml. The whole mixture was further prehomogenized for another 2-3 minutes (ultra turrax) . The pre-emulsion was homogenized in a high pressure homogenizer (MHO Microfluidizer, Microfluidics Corporation, Newton, Mass.). The product was processed 5 times through the Microfluidizer. In order to keep the product temperature below 20°C the product was passed through an ice slurry by each cycle. The oxidation of lipids was prevented by running the process under Argon and by using liquids saturated with Argon.

The product was filled in a suitable package and sterilized in an autoclave at 120°C for 20 minutes.

Analytical data

pH = 6.1

Osmolality = 304 mOsm/kg water Particle size (d ₂ ) = 285 nm Limulus test = < 0.5 EU/ml