Hydrophilic pharmaceutical composition containing ketoprofen lysine salt for topical use

Abstract

A hydrophile pharmaceutical composition in the form of foam is described which contains as active ingredient Ketoprofen lysine salt having a concentration between 10 and 20% p/volume of solution which allows, for topic treatment, the maximum absorption of the active principle.The foam is applied for the local treatment in painful and phlogistic conditions, of rheumatic or traumatic nature, of the articulations, of the musles, of the tendons and of the ligaments.

Description

The object of the present invention relates to a topical pharmaceutical composition in the form of foam containing as active ingredient a compound having anti inflammatory activity which belongs to the class of the arylpropionic acids.

More particularly the arylpropionic acid contained in the composition which is the object of the invention is represented by the lysine salt of 2-(8-benzoylphenyl) propionic acid, known also as ketoprofen lysine salt, a compound which forms the object of Italian Patent n.degree.1.104.556, in the name of the instant Applicant, issued on 21st Oct. 1986.

The 2-(3-benzoylphenyl) propionic acid or ketoprofen, as which the majority of the non-steroid antiinflammatories or FANS, derives its mechanism of action essentially from the inhibition of the biosynthesis of prostaglandins, prostacyclines and tromboxane. Compared to the ketoprofen, the ketoprofen lysine salt, even presenting a parallel pharmaceutical profile and a similar antiinflammatory-analgesic potency, offers the advantage of a considerably higher solubility in water and a greater gastric tolerability. The muscle-skeleton apparatus is particularly subject to possible physical trauma with a consequent formation of local inflammatory processes and therefore it is convenient to have at disposal compositions containing topical non-steroid antiinflammtory (FANS) drugs. The topical administration route is certainly the elective one for non-steroids antiinflammatory drugs, in case of local inflammatory processes because it minimizes the appearance of collateral effects, especially the gastric and renal ones, which appear during the therapy with the majority of such drugs.

With the exception of the drugs used for their surface topical effects, those which are applied on the skin have to penetrate the appropriate cutaneous layer to produce the therapeutical desired effect. The FANS, to work their action, therefore have to go through corneous layer and the vital part of the epidermis. The corneous layer, being a keratinized tissue, behaves like an artificial semipermeable membrane and the molecules of the drug penetrate by passive diffusion therethrough according to the gradient of concentration. Therefore the speed of penetration through this cutaneous layer depends on the concentration of the drug in the carrier, on its solubility in water and its coefficient of distribution between the corneous layer and the carrier.

Therefrom it derives that in order that an antiinflammatory drug may have the desired effect it has to be administrated in elevated concentrations, thus it has to be contained in high concentrations in the pharmaceutical form for topical administration.

The topical pharmaceutical composition in the form of foam which is one of the objects of the present invention, allows to concentrations between 10 and 20%, of the ketoprofen lysine salt, to be obtained concentrations. Such are concentrations not otherwise obtainable with other formulations, for example with a gel. A further advantage provided by the topical pharmaceutical composition of the invention is represented by the very low quantity of excipients contained therein which may, to some extent, interact with the skin. In particular said excipients, in the pharmaceutical composition in the form of a foam, totally amount to a percentage ranging from 5% to 10% p/volume of solution, with a very low con Lent of alcoholic excipients, i.e. lower than 5%, while in the traditional pharmaceutical forms for topical use, such as gel or cream containing FANS, the percentages of alcoholic excipients are much higher and they may even reach 40% p/volume of solution.

The pharmaceutical composition in the form of foam contains 10-20% of a ketoprofen lysine salt solution, preferably 15% of ketoprofen lysine salt solution, and is emulsified, when delivered, by means of a suitable gas, for example, a mixture of butane, propane and isobutane gases, commonly denominated butane-propane, preferably mixed in the ratio of butane: propane: isobutane=4: 4: 2, in a quantity from 3 up to 7% by weight of the solution.

The quantity of a gaseous mixture corresponding to 5% by weight the solution is particularly preferred. In the pharmaceutical composition in the form of foam other components, such as a surfactant or an ionic or non-ionic emulsifier, an emollient substance, a thickener and optionally small quantities of a scent and of a bacteriostatic substance are also included. As ionic emulsifier potassium laurylsulphate may be used and as non-ionic emulsifier non-ethoxylated derivatives such as sorbitan esters or ethers (SPAN) or ethoxylated derivatives such as, for example, polyoxyethylenesorbitan ethers or esters and polyoxymethylene ethers and esters (Cremophor, myrj) may be used. The quantity of the emulsifier is between 2 and 8% by volume of solution. The quantity particularly preferred for ionic emulsifiers is between 2 and 3% by volume of solution while for the non-ionic emulsifiers said quantity is between 3 and 5% by volume of solution.

As an emollient substance propylene glycol, glycerin or polyethyleneglycols having a molecular weight between 300 and 3.000 (Carbowax of Polywax 300-1.500-3.000) may be used. The quantity of emollient varies from 2 to 6% by volume of solution; quantities between 3 and 4% by volume of solution are particularly preferred.

As a thickening substance, substituted amides of saturated or unsaturated fatty acids of vegetable origin (Comprelan Henkel); substituted and/or salified celluloses such as, for example, methylethylcellulose, sodium carhoxymethylcellulose, methylcellulose, isopropylmethylcellulose; substituted vinyl pyrrolidone polymers having different molecular weights such as, for example, polyvinylpyrrolidone K 30; carboxypolymethylene (Carbopol) may be used. The quantity of the thickener varies from 0.2 to 3% by volume of solution. The scent optionally present may be constituted by netolin lavender in a quantity from 0.05% to 0.2% by volume of solution.

The bacteriostatic substance which, although not strictly necessary, can be present to assure the microbiological purity as time passes, may be constituted by benzoic acid and by its esters (Nipagin-Nipasol) or by benzilic alcohol and is added in a quantity from 0.1 to 0.5% by volume of solution. The topical antiinflammatory pharmaceutical composition in the form of foam, the object of the present invention, is of simple application and it is suitable for the local treatment of painful and phlogistic conditions, of rheumatic or traumatic nature, of the articulations of the muscles, of the tendons and of the ligaments. A suitable posology foresees that, according to the area that has to be treated and of the entity of the inflammation, the foam can be applied 2-3 times a day on the effected parts and made to penetrate by lightly rubbing.

The examples which follow are given only to illistrate, without limiting, the object of the invention.

EXAMPLE 1

Ketoprofen lysine salt (1.5 kg) is dissolved under stirring in depurated water (6.5 1).

In another container are placed:

Polysorbate 80 (0.4 kg); propylene glycol (0.4 kg); PVP K25 (polyvinylpyrrolidone) (0.3 kg); nerolin lavender (0.02 kg); benzilic alcohol (0.03 kg) and water q.s. to 1 liter.

The second solution is added, under stirring, to the first one and then, it is brought to volume (10/1) with water.

is controlled (range limits: 7-8.0). It is filtered under pressure and it is divided in small bottles. The valve is installed and secured to the small bottle. It is pressurized by loading butane-propane gas (5% by weight).

The final composition of tile solution for 100 ml is the following:

______________________________________Ketoprofen lysine salt 15.0 gPolysorbate 80 4.0 gPropylene glycol 4.0 gPolyvinylpyrrolidone (PVP K25) 3.0 gNerolin lavender 0.2 gBenzilic alcohol 0.3 gDepurated water q.s. to 100 ml______________________________________

EXAMPLE 2

Operation is carried out similarly to what was described in Example 1 suitably varying the excipients and the following final composition is obtained:

______________________________________Ketoprofen lysine salt 15.00 gSodium Laurylsulphate 2.00 gPolyethyleneglycole (Carbowax 300) 5.00 gSodium Carboxymethylcellulose l.v. 0.25 gNerolin lavender 0.20 gNipagin 0.10 gNipasol 0.02 gDepurated water q.s. to 100 ml______________________________________

EXAMPLE 3

Operation is carried out similarly to what was described in Example 1 suitably varying the excipients and the following final composition is obtained:

______________________________________Ketoprofen lysine salt 15.00 gSpan 20 5.50 gGlycerin 3.00 gHydroxypropylmethylcellulose E 3 0.35 gNerolin lavender 0.20 gBenzoic acid 0.12 gDepurated water q.s. to 100 ml______________________________________

EXAMPLE 4

Operation is carried out similarly to what was described in Example 1 suitably varying the excipients and the following final composition is obtained:

______________________________________Ketoprofen lysine salt 15.00 gCremophor EL 4.00 gPropylene glycol 4.00 gMethylethylcellulose 0.30 gNerolin lavender 0.20 gNipagin 0.12 gDepurated water q.s. to 100 ml______________________________________

EXAMPLE 5

Operation is carried out similarly to what was described in Example 1 suitably varying the excipients and the following final composition is obtained:

______________________________________Ketoprofen lysine salt 15.00 gMyrj 52 5.00 gGlycerin 3.00 gPolyvinylpyrrolidone K 30 4.00 gNerolin lavender 0.15 gBenzilic alcohol 0.30 gDepurated water q.s. to 100 ml______________________________________

The absorption of the hydrophilic solution of ketoprofen lysine salt was studied on Female rabbits (New Zealand, 9-11 weeks) after topical administration of the composition in the form of foam at different concentrations (5%, 10%, 15% and 20%) which all had the excipient composition as described in Example 1. The foam was applied to 4 groups of rabbits (n=3) on the back, previously depilated (24 hours before the treatment), in an area of 100 cm.sup.2 (10 cm .times.10 cm), at a dose role of 10 mg/kg (average weight of animals 2000 g .+-.200 g).

The animals, immediately after the treatment, were put in metab obolic cages. 2 ml of blood were taken at the following times: 0 (pre-dose), 15, 30, 60, 120, 240 and 360 minutes and urines were collected during the periods; 0-6 h, 6-12 h and 12-24 h after administration.

The determination of ketoprofen acid level in the plasma and urine was made by the HPLC method using as internal standard (IS) the Suprofen acid.

The samples of plasma, after adding IS adding were acidified with 1M potassium phosphate, pH=2.0 and extracted with ethyl ether. The urines, after adding IS underwent alkaline hydrolysis by 1N NaOH for 30 minutes, were then neutralized by adding 1N HCl, finally acidified to pH=2.0 with 1M potassium phosphate, and then extracted with ethyl ether. The ether phases of plasma and urine were evaporated to dryness under nitrogen. The residues of the plasma and urine extracts were taken up in 0.2M NH.sub.4 -formiate (pH=6.5) and injected in HPLC (volume of injection 20 .mu.l ).

The chromatography conditions are as follows:

Column: Merck Lichrospher 10RP-18 5 .mu.m 125.times.4 mm with mobile phase pre-column: NH.sub.4 -formiate 0.2M pH (35% CH.sub.3 CN) Flow rate: 1 ml/min Detection: UV to 258 nm

The applied method is linear within the tested range 0.020-2 .mu.g/ml (r.sup.2 0.99 ) for plasma and of 0.05-25 .mu.g/ml (r.sup.2 0.99) for urines. The limit of the method is 0.01 .mu.g/ml and the minimum concentration detectable is 0.05 .mu.g/ml for both plasma and urine.

The administration in the rabbit of the hydrophilic solution of ketoprofen lysine salt in the form of foam at 5%, 10%, 15% and 20% at a dose rate of 10 mg/kg does not result levels higher in the plasma than the detectable limit of the method, while dosable levels of ketoprofen have been found in urines.

In Table 1 are shown the values of total excretion in each animal and the relative average (.+-.DS). The FIG. 1 shows how after the application of the 5%, 10%, 15%, and 20% solutions there is an increase of the levels of ketoprofen in the urines which is proportional to the concentration of the active principle present in the composition.

The direct comparison between the concentrations of ketoprofen found in each period of urine collection and the concentrations of the active principle in the compositions was made with the Duncan test. The obtained results show that the formulations containing 5%, 10% and 15% of ketoprofen lysine salt are statistically different (p 0.05) from each other, while a statistical difference did not exist between the 15% formulation and the 20% one.

TABLE 1______________________________________Cumulative levels of ketoprofen acid after theapplication on the skin of a rabbit of 10 mg/kg of ketoprofenlysine salt foam at 5%, 10%, 15% and 20%. Ketoprofen lysine salt foam at 5%Collecting Cumulative urine excretion (.mu.g)time 1 2 3 Average .+-. SD______________________________________0-6 h 50 48 43 47 .+-. 46-12 h 130 123 113 122 .+-. 912-24 h 153 146 143 147 .+-. 5______________________________________ Ketoprofen lysine salt foam 10%Collecting Cumulative urine excretion (.mu.g)time 4 5 6 Average .+-. SD______________________________________0-6 h 126 122 121 123 .+-. 136-12 h 261 268 256 262 .+-. 612-24 h 286 296 275 286 .+-. 11______________________________________ Ketoprofen lysine salt foam 15%Collecting Cumulative urine excretion (.mu.g)time 7 8 9 Average .+-. SD______________________________________0-6 h 195 205 196 199 .+-. 66-12 h 387 359 386 377 .+-. 1612-24 h 473 473 456 467 .+-. 10______________________________________ Ketoprofen lysine salt foam 20%Collecting Cumulative urine excretion (.mu.g)time 10 11 12 Average .+-. SD______________________________________0-6 h 198 205 208 204 .+-. 56-12 h 381 390 406 392 .+-. 1312-24 h 471 490 487 483 .+-. 10______________________________________

Claims

1. A topically applicable, transdermally deliverable anti-inflammatory foam-form composition which, upon topical application, penetrates through skin into effective contact with an inflamed area beneath the skin comprising, based on the total volume of the composition:

at least about 67% water as a main constituent;

less than 15 percent by volume of a liquid excipient, comprising:

less than 5% volume alcohol, and

2 to 8% by volume of at least one emulsifier, which quantity of excipient is insufficient to produce adverse effects;

0.2 to 3 percent by volume of a thickening agent; and

12 to 18 percent by volume, which is sufficient to transdermally transport an amount, which is sufficient to inhibit the substantial sub-cutaneous biosynthesis of prostaglandines, prostacyclines and tromboxane related to said inflamed area beneath the skin, of a transdermally penetrating anti-inflammatory material consisting essentially of a lysine salt of ketoprofen;

wherein said composition has been foamed by the action of about 3 to 7% by weight, based on the weight of the entire admixture, of a propellant comprising at least one member selected from the group consisting of propane, butane and isobutane which has been admixed with said composition under sufficient pressure to prevent foaming thereof and

wherein said pressure has been reduced a sufficient amount to form said foam.

2. A foam composition as claimed in claim 1, which contains an addition, at least one emollient.

3. A foam composition as claimed in claim 2 comprising 2 to 8 volume percent of said emulsifier.

4. A foam composition as claimed in claim 2 wherein said emulsifier is a non-ionic emulsifier.

5. A foam composition as claimed in claim 2 wherein said emulsifier is an ionic emulsifier.

6. A foam composition as claimed in claim 2 comprising 3 to 4 volume percent of said emollient.

7. A foam composition as claimed in claim 2 comprising in addition, 0.05 to 0.2 volume percent of a scent.

8. A foam composition as claimed in claim 2 comprising in addition, 0.1 to 0.5 volume percent of a bacteriostat.

9. A foam composition as claimed in claim 4 wherein said non-ionic emulsifier is at least one member selected from the group consisting of sorbitan esters, sorbitan ethers, polyoxymethylene esters, polyoxymethylene ethers, polyoxymethylene sorbitan esters, and polyoxymethylene sorbitan ethers.

10. A foam composition as claimed in claim 5 wherein said ionic emulsifier is a lauryl sulfate.

11. A foam composition as claimed in claim 2 wherein said emollient is at least one member selected from the group consisting of glycerine, propylene glycol, and polyethylene glycol.

12. A foam composition as claimed in claim 2 wherein said thickener is at least one member selected from the group consisting of amides, cellulose, vinyl pyrrolidone polymers, and carboxypolymethylene.

13. A foam composition as claimed in claim 2 wherein said bacteriostat is at least one member selected from the group consisting of benzoic acid, benzoic acid esters, and benzylic acid.

14. A foam composition as claimed in claim 1 comprising 15 volume percent of said ketoprofen lysine salt.

15. A foam composition as claimed in claim 1 wherein said propellant gas comprises said butane, propane and isobutane in volumetric proportions relative to each other of 4:4:2.

16. A foam composition as claimed in claim 15 wherein said propellant comprises 5 volume percent of said composition.

17. A foamable composition comprising, based on the entire weight and volume of said composition, respectively;

an active ingredient composition comprising an aqueous solution comprising:

at least 67 volume percent water;

12 to 18 volume ketoprofen lysine salt; and

less than 15 volume percent of an excipient including:

less than 5 volume percent alcohol;

2 to 8 volume percent of at least one ionic or non-ionic emulsifier; and

0. 2 to 3 volume percent of a thickening agent;

and

a propellant comprising about 3 to 7% by weight, based on the weight of the entire foamable composition, of at least one member selected from the group consisting of propane, butane and isobutane;

wherein the proportion of ingredients is such that said ketoprofen lysine salt is present in said foamable composition in a proportion which is sufficient to cause sufficient ketoprofen lysine salt to penetrate transdermally into effective contact with a subcutaneous inflammation and to thereby exhibit an antiinflammatory effect on said inflammation; and

the ingredients of said excipient are present in said foam in proportions which are insufficient to cause the substantial subcutaneous biosynthesis of prostaglandines, prostacyclines and tromboxane related to said inflamed area beneath the skin.

18. A topically applicable, transdermally delivered pharmaceutical, antiinflammatory composition consisting essentially of a foam resulting from the foaming of the composition claim in claim 17.

19. A topically applied composition as claimed in claim 18 wherein:

the proportion of ingredients is such that said ketoprofen lysine salt is present in said foam in proportion which is sufficient to cause sufficient ketoprofen lysine salt to penetrate transdermally into effective contact with a subcutaneous inflammation and to thereby exhibit an antiinflammatory effect on said inflammation; and

the ingredients of said excipient are present in said foam in proportions which are insufficient to cause the substantial sub-cutaneous biosynthesis of prostaglandines, prostacyclines and tromboxane related to said inflamed area beneath the skin.