AU645366B2 - Aerosol composition and a process preparing same - Google Patents

Description

P/00/011 20/5101 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990 6"*'-453

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT S On 00 Application; Number: Lodged: OS*eCe

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0eS* 95 *5 0

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*0ee 05

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*5 S S *0 Invention Title: AEROSOL COM~POSITION AND A PROCESS PREPARING SAME The following statement is a full descriptlon of this invention, including the best method of performing It known to us AEROSOL COMPOSITION AND A PROCESS FOR PREPARING SAME The ihvention relates to a new aerosol composition in suspended form and a process for preparing same.

The process according to the invention is carried out by mixing a dispersing medium, an active agent insoluble in the dispersing medium, surfactant(s) and/or dispersing agent(s).

The composition according to the invention can be used *0 *e S. mainly as pharmaceutical composition for inhalation, or 10 intranasally or externally.

The aerosol composition according to the invention contains the suspension of the liquid lispersing medium ("propellant") and the active agent of appropriate particle size, wherein the active agent is insoluble in the propellant and the suspension is formed by the use of surfactants and/or 0 dispersing agents.

When using the compositions the dispersing medium evaporates and the surfactant(s) and the active agent(s) distributed in its vapour penetrate to the place of 20 application (lungs, nasal. mycoderm etc.).

The surfactants and/or dispersing agents to be used have to fulfil the following requirements: a) they have to be inert against the active agent and the dispersing medium; they should be biologically degradable and should be no toxic; they should irritate contacting parts and organs of the body at the lowest degree possible; further they should have appropriate odour and taste; b) they shoul. provide appropriate grade of dispersion in the A4784-62-PT 2 "propellant gas", further stability for the suspension (characterized by the following features: volume of settling, ability for being redispersed, amount of material adhering to the valve or the walls of the bottle, particle size distribution); c) they should not inhibit (rather enhance) the dissolution of the active agent in the body fluids.

The appropriate choice of the type and amount of surfactant(s) and/or dispersing agent(s) meeting the above 10 requirements is a rather difficult task.

The prior art teaches first of all the use of the following surfactants and/or dispersing agents for preparing aerosol compositions in suspended form: oleyl alcohol, oleyl acid and esters thereof formed with se** 15 polyvalent alcohols such as sorbitan monooleate e S" sorbitan trioleate (Span-85R), soya lecithin, etc. [Aerosol :Age, August 1985; Canadian Patent No. 1,120,441].

Now we have surprisingly found that the use of compounds of the general formula influences the properties of the composition very advantageously both in a hydrophobic medium (in the suspension used) and in a hydrophilic medium (in body fluids).

On the one hand, the properties characterizing the stability of the composition (suspension) can thereby significantly be improved, so in some cases the amount of surfactant(s) in the composition can be reduced or even eliminated. On the other hand, the active agents are dissolved by the body fluids from compositions containing a compound of 3 the general formula as dispersing agent at a higher rate than from compositions containing the above-mentioned known surfactants and/or dispersing agents.

Accordingly the invention is a process for preparing an aerosol composition in suspended form by mixing a dispersing medium, an active agent insoluble in the dispersing medium, surfactant(s) and/or dispersing agent(s), in which a compound of the general formula (I)

CH

3 -(CH9 )-CH=CH-(CH 2 -COO-CH-(CH )-CH=CH-(C)-CH3 1 I s* is used as the dispersing agent, wherein x, y, v and z are integers having the value of 6, 7 or 8.

Among the different structural isomers of the compounds of 15 the general formula the cis,cis derivatives can be used most preferably.

From among the compounds of the general formula the use of oleyl oleate has been proved to be especially advantageous y, v and z each have the value of 7).

The oleyl oleate as dispersing agent is a component of emulsion systems for use as cosmetics and pharmaceutical compositions. Its use in aerosols in suspended form still has not been known.

Advantageous compositions may contain 0,001 to 20 by mass, preferably 0.5 to 10 by mass, of an active agent, 0.01 to 5 by mass, preferably 0.3 to 2 by mass, of a compound of the general formula wherein x, y, v aid z are integers having the value of 6, 7 or 8, 0 to 5.0 by mass, 4 preferably 0.01 to 1 by mass, of an other surfactant, and 66 to 99 by mass, preferably 85 to 98 by mass, of a dispersing medium.

In the compositions according to the invention a wide variety of ;Lctive agents can be used.

The compositions according to the invention can be used in a wide field of effect, first of all for inhalation, further ,B for nasal and eventually for external use.

0 In the following a list of fields of effect where the 10 compositions according to the invention can be used and some representatives thereof are given. This list is only illustrative and serves as a guide for a person skilled in the art. Thus, the compositions according to the invention can contain as active agents sympathomimetics adrenalin, 15 isoprenaline, orciprenaline, terbutaline, salbutamol, phenoterol, rimiterol); anticholinergic bronchial wideners ipratropinum); corticosteroids heclomethasone dipropionate, betamethasone valerate, triamcinolone acetonide, budesonide); other hormones oxytocin, insulin, sex hormones, glucagon) or desmopresin as antidiabetics; vasopressin as antidiuretic hormone; mucolytica N-acetyl cysteine, sodium mercaptoethane sulfonate); calcium antagonists nifedipin); antibiotics carbenicillin, gentamicin); methyl xanthines theophyllin, aminophyllin); antihistamines (tripelennamine, chloropheniramine maleate, diphenyl hydramine hydrochloride); antiviral agents (e.g.

Ribamicin); cardiovascular agents nitroglycerine); antimigraine agents ergotamine); and mixtures thereof.

5 The application of antiasthmatic compositions according to the invention for inhalation or intranasal use have been found to be especially preferable.

Sodium chromoglycate can be very advantageously used as the active agent of antiasthmatic compositions, wherein this agent can be preferably used without drying (with a water content of about 9 by mass) for preparing compositions according to the invention. This is surprising because according to the Canadian patent specification No. 1,120,441 10 only an active agent with a water content of less than 5 by mass is appropriate for preparing aerosol compositions in suspended form of suitable quality.

Bromine hexinium chloride can be preferably used as active agent as well.

15 The particle size of the active agents used is an important aspect. It is a requirement relating to aerosol compositions that their active agent be microcrystalline or micronised, i.e. of appropriate particle size.

The necessary particle size depends on the field of j application. Generally the particle size necessary for the given field of application is used. So in case of compositions for inhalation the size of 90 of the particles should be less than 10 im, preferably less than 5 jm, in case of compositions for nasal use the size of 30 of the particles should be less than 20 im, while in case of compositions for external use the size of the particles is determined by the features of the spraying nozzle system.

The active agent of necessary particle size can be 6prepared by appropriate crystallization or any known method of pulverization.

The concentration of the active agent(s) generally amounts to 0.001 to 20 by mass, preferably 0.5 to 10 by mass, and most preferably 1 to 5 by mass.

Optionally furtber surfactants and/or dispersing agents can be used beside the compounds of general formula Mixtures of oleyl oleate and different sorbitan oleates can preferably be used. In such a case the amount of scrbitan 10 oleate(s) is only a fraction of that necessary to provide the desired properties of a composition without oleyl oleate.

The quantity of further surfactants and/or dispersing .agents in the composition generally amounts to 0 to 5 by mass, preferably 0.001 to 1 by mass and most preferably 0.01 S 15 to 0.1 by mass.

As a dispersing medium ("propellant") non-toxic compounds being volatile at room temperature and atmospheric pressure, various alkane derivatives, first of all various chlorofluoroalkanes, can be used. A mixture of the mentioned propellants and nitrogen is applicable as well. Thus e.g. monofluorotrichloromethane (propellant gas 11), difluorodichloromethane (propellant gas 12), trifluorotrichloroethane (propellant gas 113) and tetrafluorodichloroethane (propellant gas 114) can be used. The quantity of the propellant gas generally amounts to 66 to 99 by mass, preferably 85 to 98 by mass.

The compositions according to the invention, especially those for nasal or external use, may contain further auxiliary agents and carriers, for example a buffer to adjust the pH 7 value a phosp.,ate buffer), antioxidants (ascorbic acid, bisulfites), conserving agents benzalkonium chloride), and water.

The aerosol compositions can be prepared by known methods, i.e. after mixing the ingredients the mixture is filled into bottles by the so-called "cold" method or under pressure (eventually using a combination of the two methods).

The ingredients are advantageously mixed in the following sequence: the surfactant(s) and/or dispersing agent(s) are 10 dissolved in the (optionally precooled) liquid dispersing medium followed by the addition of the active agent(s).

*S

For mixing a stirrer conventionally used for preparing suspensions is applied at a higher revolution per minute (at least 1000 revolutions per minute).

15 The bottles have to be equipped with a dosing apparatus providing the appropriate dose. For example the dose of active agent in case of sodium chromoglycate can preferably be fixed at a level of 1 to 5 mg. In clinical tests the composition according to Example 3 with a dose of 1 mg proved to have the *a same effect as a capsule with the usual dose of 20 mg.

The preparations containing the following amount of ingredients (given in by mass) have been found to be especially preferable: sodium chromoglycate 1 to 2 oleyl oleate 0.3 to 2 sorbitan trioleate 0 to 0.2 propellant gas (dispersing medium) up to 100 As mixed propellant gases mixtures of the following 8 composition (given in by mass) can preferably be used: propellant gas 11 35 to propellant gas 12 10 to propellant gas 114 10 to The properties of the compositions according to the invention are compared to those of known compositions as follows.

g. A) The absorption of the active agent from compositions according to the invention A.nd from known compositions, resp., 10 was determined in vitro with a MUhlemann-type dialysis apparatus shown in Fig. 1. The explanation of the symbols used in Fig. 1 is as follows: 1 sample addition 2 glass tube 15 3 receptor phase (pH 7.4; phosphate buffer) 4 from the thermostat 5 double-wall vessel for dialysis 6 to the thermostat 7 dialyse-membrane 8 magnetic stirrer 9 magnetic stirrer equipment (IKAMAG RCT) As membrane a so-called membrane for renal dialysis (from HOECHST, Germany) was used. The membrane was pre-treated for 17-18 hours in a phosphate buffer having the pH-value of 7.4 prior to measurements.

ml of buffer solution was filled into the apparatus for the measurement. The temperature of the measuring system was held at the value of 37 the stirrer was operated at 9 S0 06 0 0 0 *0 100 revolutions/minute.

Each of the different aerosol compositions were investigated using 3 parallel "doses" contacted with the membrane. (1 "dose" relates to the amount of composition released from the bottle by operating the dosing valve once after shaking the bottle; it contains about 1 mg of sodium chromoglycate.) The amount of the active agent was determined by precisely weighing the bottle prior and after releasing a dose, using an analytical balance.

After given periods of time specimens were taken from the receptor phase of the system and the amount of sodium chromoglycate transported from the donor phase was measured using a spectrophotometer.

The results of the analytical measurements are given in 15 Table 1.

Table 1 Change of concentration of the diffused active agent (in by mass) against time (in hours) T i m e, hours Example 1 2 3 4 5 6

S

0

II

III

IV

1 3A 22.62 15.4+2 3.5±1.5 5.6±1.5 44.9±2 51.6±2 32.0+2 36.6±3 27.1±2 10.2±1 10.8±1 57.2±2 62.9±3 50.2±3 48.3±6 36.3±2 46.8±2 42.3±2 58. ±4 70.1±4 56.4±4 54.7±5 42.9±4 58.3±4 46.8±2 59.1±4 73.3±3 58.7±3.5 58.1±7 46.9±5 61.9±6 47.8±5 59.9±5 74.3±6 60.9±5 60.9±6 48.8±6 64.0±6 48.5±6 61.6±5 74.7±6 62.8±5 10 (The compositions were prepared according to the given Examples.) It can be seen from the above test results that the active agent dissolves at a substantially higher rate from compositions containing oleyl oleate (compositions prepared according to Examples 1, 3A and 5) than from the comparative compositions I to IV compo:ti.ons containing oleyl oleate exert a faster effect).

B) Table 2 summarizes the physical properties characterizing the different compositions (the symbols of the 10 examined compositions are identical with those in Table 1).

The investigated parameters and the symbols thereof used in Table 2 are as follows: volume of settling v/v) VSE ability for being redispersed (and the number of S 15 shaking necessary for being redispersed, resp.; shaking refers to a change of the position by 1800 ABR amount of sediment ASE material adhering on the aerosol bottle (mg) MAB material adhering on the valve of the aerosol bottle (mg) MAV mean particle size, particle size distribution (determined using a HIAC CP-420 type apparatus).

Table 2 Mean particle size based on Example VSE ABR PSE MAV MAB number volume I 2.9 30* low 22.3 9.50 3.20 9.41 III 2.6 25* low 23.6 7.70 3.38 9.77 11 00 OS B. S w 0 0 0 Bl, .6 .5 00 *r 0

I

Table 2 continued IV 2.5 22* low 22.9 9.32 3.92 10.73 35 2 high 23.5 7.20 3.33 7.40 1 30 3 high 26.2 6.40 2.70 5.46 3A 18.5 2 medium 16.2 6.20 3.13 5.74 The compact sediment Is separated from the surface of the bottle but it is not dispersed in the liquid.

The invention is further illustrated by the following nonlimiting examples.

LO Example 1 Composition: by mass Disodium chromoglycate (with a water content of 9% by mass) 1.7 Oleyl oleate 1.3 Monofluorotrichloromethane 70.7 Difluorodichloromethane 13.15 Tetrafluorodichloroethane 13.15 100.00 The monofluorotrichloron.ethane is cooled to a temperature of 10+1 OC. Oleyl oleate is dissolved in the cooled monofluorotrichloromethane and small portions of disodium chromoglycate as active agent are added to the mixture under continuous stirring (at about 1400 revolutions/minute). The mixture is stirred during a period of 45 minutes (at about 2800 revolutions/minute). The thus-obtained suspension is filled into aerosol bottles under continuous stirring (at about 1400 revolutions/minute) and cooling. The bottles axe closed using appropriate dosing valves, then both of the further gas 12 components, mixed or separately, are filled under pressure into the bottles via the valve.

Example 2 Composition: Disodium chromoglycate (with a water content of by mass

BO

6 6 S. .6

S

0 a.

6 em.

0O 6er 0SS 6* 0

SS

6

S

*r 9% by mass) 3.3 Oleyl oleate 0.6 Polyoxyethylene sorbitan monooleate 0.1 10 Monofluorotrichloromethane 67.0 Difluorodichloromethane 14.5 Tetrafluorodichloroethane 14.5 100.00 The monofluorotrichloromethane is cooled to a temperature 15 of 5+1 OC. Oleyl oleate and then polyoxyethylene sorbitan monooleate are dissolved in the cooled monofluorotrichloromethane. The thus-obtained solution is added to the mixture of difluorodichloromethane and tetrafluorodichloroethane cooled to oC. At this temperature the disodium chromoglycate as active agent is added in portions to the mixture under steady stirring (at about 2500 revolutions/minute). After a subsequent stirring period of 20 to 30 minutes the suspension is filled into aerosol bottles under continuous stirring and cooling, and the bottles are closed using appropriate dosing valves.

'I 13 Example 3 composition containing a dose of 1 mg (3A) 5 mg (3B)

V.S

0 S composition: by mass Sodium chromoglycate 1.7 3.3 Oleyl oleate 0.66 0.53 Sorbitan trioleate 0.05 0.05 Propellant gas 11 68.64 69.82 Propellant gas 12 14.475 13.15 10 Propellant gas 114 14.475 13.15 The composition is prepared in accordance with the process described in Example 1 with the difference that the sorbitan trioleate is dissolved after dissolution of the oleyl oluate.

4505 Example 4 Composition: %by mass Bromine hexinium chloride 2.040 Oleyl oleate 0.680 Sorbitan trioleats 0.170 Trifluorotrichloroethane 3 5.742 Dif luorodichloromethane 30.650 Tetraf luorodichioroethane 30.650 Aroma 0.068 100 D The trifluorotrichioroethane is cooled to the temperature of !0+1 0 C. Oleyl oleate and then sorbitan trioleate are, dissolved in the cooled trifluorotrichloroethane and small 14 amounts of bromine hexinium chloride are added to the mixture under steady stirring (at about 1500 revolutions/minute). The mixture is stirred during a period of 50 minutes (at about 2500 revolutions/minute). The thus-obtained suspension is filled into aerosol bo,tles under continuous stirring (at about 1400 revolutions/minute) and cooling. The bottles are closed using appropriate dosing valves and both of the further gas components, mixed or separately, are filled under pressure into the bottles via the valve.

10 Example Composition: by mass Sodium chromoglycate 1.7 Oleyl oleate 0.66 Propellant gas 11 69.74 P *op 15 Propellant gas 12 14.45 Propellant gas 114 14.45 The composition is prepared in accordance with the process described in Example 1.

Compositions I to IV Compositions according to the prior art (II to IV) and a comparative composition are prepared in accordance with the process described in Example 1 with the difference that the sorbitan trioleate is dissolved in the cooled monofluDrotrichloromethane, instead of oleyl oleate. The amounts of the components are given in Table 3.

A I I 15 Table 3 Name of ingredients Disodium chromoglycate Sorbitan trioleate Monof luorotrichioromethane Dif luorodichioromethane Tetrafluorodichloroethane Amount in 1.7 1.7 0.1 70.0 69.9 14.15 14.15 14.15 14.15 by mass III IV 1.7 1.7 0.5 69.5 68.5 14.15 14.15 14.15 14.15 Sb SB B B

S

so Ba U

B

Ba

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B U*B

B'

0 ae~ S 05 04 4 O B&

S

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0 5504 Sb 0 a a

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*0Sd~hV B B a 46 U 00

Claims (4)

1. A process for preparing an aerosol composition in suspended form by mixing a dispersing medium, an active agent insc'able in the dispersing medium, surfactant(s) and/or dispersing agent(s), in which a compound of the general formula (I) S CH 3 H2)x-CH=CH-(CH2)y-COO-CH 2 -(CH 2 )v-CH=CH-(CH)z-CH 3 S 10 (I is used as the dispersing agent, wherein x, y, v and z are integers having the value of 6, 7 or 8.

2. The process as claimed in claim 1, in which a compound of the general formula is used in an amount of 0.01 to 5 S* 15 by mass, preferably 0.3 to 2 by mass, wherein x, y, v and z are as defined in claim 1. a. 3. The process as claimed in claim 1 or 2, in which oleyl oleate is used as the compound of the general formula wherein x, y, v and z have the value of 7.

4. The process as claimed in any of the preceding claims, in which 0.001 to 20 by mass, preferably 0.5 to 10 by mass, of an active agent, 0.01 to 5 by mass, preferably 0.3 to 2 by mass, of a compound of the general formula wherein x, y, v and z are as defined in claim 1, 0 to 5.0 by mass, preferably 0.01 to 1 by mass, of an other surfactant, and 66 to 99 by mass, preferably 85 to 98 by mass, of a dispersing medium are used. -17 The process as claimed in any of the preceding claims, ini which an antiasthmatic active agent, preferably sodium chromoglycate, is used.

6. The process as claimed in any of tY- preceding claims, in which bromine hexinium chloride is u~ad as the active agent. S. DATED this 7th day of November 1991. EGIS GYOGYSZERGYAR 0 WATERM4ARK PATENT TRADEM4ARK ATTORNEYS "TIHE ATRIUM" 290 BURWOOD ROAD HAWTHORN. VIC. 3122. a t AEROSOL COMPOSITION AND A PROCESS FOR PREPARING SAME ABSTRACT The invention relates to a new aerosol composition in suspended form and a process for preparing same. The process according to the invention is carried out by mixing a dispersing medium, an active agent insoluble in the dispersing medium, surfactant(s) and/or dispersing agent(s), in which a compound of the general formula (I) CH 3 -(CH 2 )-CH=CH-(CH 2 COO-CH 2 (CH 2 )CH=CH-(C )z-CH3 a S(I) is used as the dispersing agent, wherein x, y, v and z are independently integers having the value of 6, 7 or 8. The composition according to the invention can be used as pharmaceutical composition for inhalation, or intranasally L or externally. I l S 4 .0