MXPA00008726A - Valve for aerosol container - Google Patents

Abstract

The invention provides a valve for an aerosol container suitable for use in dispensing a quantity of the contents thereof. The valve components comprise a fluorinated polymer and/or a fluorinated coating which have been found to reduce drug deposition in the valve.

Description

VALVE FOR AN AEROSOL CONTAINER The invention provides a valve for an aerosol container suitable for use in the distribution of a dose of the same content and which can be used in the treatment of asthma and other diseases. In particular, the invention provides a valve for suitably inhaling a metered dose for the use of distributed metered doses of medicaments.

Containers for aerosol formulations commonly comprise a small bottle body (cylindrical container) attached to the valve. The valve comprises a valve stem with which the formulations are distributed. The valve generally includes a rubber valve seal that is intended to allow reciprocating movement of the valve stem which prevents the propellant from escaping from the container. Metered dose inhalers include a valve which is designed to release a measured amount of an aerosol formulation to the container by activation. Such metering valve generally comprises a metering chamber which is of a volume REF .: 122362 established which directs or points to the administrator by activation a predetermined and precise dose.

Valves suitable for use in the invention are available from manufacturers well known in the aerosol industry, for example, from Valois, France (for example DF10, DF30, DF60), Bespa pie, United Kingdom (for example BK300, BK356 , BK357) and 3M-Neotechnic Limited, United Kingdom (for example Spraymiser ™). Dosing valves are used in association with commercially available containers such as aluminum containers, suitable for delivering pharmaceutical aerosol formulations.

Aerosol formulations which are generally used comprise a suspension of a medicament, one or more liquid propellants, optionally with a co-propellant, and optionally an adjuvant such as a solvent or a surfactant, although the invention may be applicable for dispersion. of any aerosol formulation. The aerosol formulations are under pressure in the container.

It has been found that conventional aerosols, particularly metered dose inhalers, suffer a deterioration in their performance due to the deposition of the medicament particles in the valve component, particularly in the metering chamber. This leads to a high occurrence of inconsistency in the doses of the medication that is administered which becomes particularly acute on the increase in the number of activations. The problem of medicament deposits in conventional aerosols is particularly exacerbated when excipient-free aerosol formulations are used based on the hydrofluoro alkane (HFA) 134a and 227 propellants. It has also been found that the drug reservoir is increased. with the storage of the aerosol, particularly when the aerosol is stored at high temperature and / or high humidity.

The invention provides a valve for an aerosol in which there is a significantly reduced drug reservoir compared to conventionally available valves when the valve is used in aerosols comprising aerosol formulations for inhalation. In particular, the invention provides a metering valve having a metering chamber in which there is a significantly reduced medication reservoir.

According to the present invention this discloses a valve for an aerosol container for distributing a suspension or solution of a substance in a liquid propellant contained herein, wherein the valve comprises a valve body defining a chamber, a transfer passage in the which a dose of substance that is distributed can pass from the container to the chamber, and the distributing means which allow the substance to be distributed, wherein the chamber comprises a fluorinated polymer.

The invention further provides an aerosol container which comprises a valve according to the invention, and an inhalation device, preferably a metered dose inhaler, which comprises the aerosol container.

The invention further provides a method for reducing the drug reservoir in a metering chamber for use in a metered dose inhaler by the use of a fluorinated polymer according to the invention.

The invention further provides a valve for an aerosol container as described above wherein the surface of the chamber, eg, the dosing chamber, in contact with the substance to be dispensed is coated with a fluorinated material including fluoride coatings, plastic materials comprising fluorinated materials etc.

The fluorinated coatings are preferably a plasma coating, for example, a CF4 plasma coating. Preferably the fluorinated plasma coating CF4 is applied to the dosing chamber of a metering valve which can be made of any conventionally used plastic material such as acetal, polyester, etc. The plasma coating may consist of a fluoropolymer placed below the surface of the valve component, preferably the chamber, by polymerization or direct modification of the surface of the material by exchange of hydrogen ions in the material with fluorinated ions. The coating process typically takes place at room temperature. The components to be coated are placed inside the chamber where they are evacuated. The fluorine monomer or fluorine source is introduced to the chamber with a controlled proportion. The plasma is ignited inside the chamber and maintained for a given time at a selected adjusted power. At the end of the treatment the plasma is extinguished, the chamber is washed abundantly and the products collected. In the polymerization process, a thin layer of the plasma polymer will be attached to the surface of the chamber, preferably a metering chamber, or any other surface of the valve to be coated.

The fluorinated polymers can be selected from any conventionally used fluorinated polymer / copolymer or mixtures thereof or mixtures of the fluorinated polymers in combination with non-fluorinated polymers conventionally used in the manufacture of valves, such as acetal, polyester (PBT) as well as mixtures of polymers with, for example, stainless steel (for example a mixture of PBT / stainless steel (PDX O96082)), etc. Examples of suitable fluorinated polymers include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), polyvinyldienofluoride (PVDF), perfluoroalkoxyalkane (PFA), polyvinyl fluoride (PVF), polychlorotrifluoroethylene (PCTFE), fluorinated ethylenepropylene (FEP), etc. Suitable copolymers include tetrafluoroethylene (TFE) with PFA, TFE with hexafluoropropylene (HFP) (available as FEP 6107 and FEP 100 from DYNEON), VDF with HFP (commercially available as Viton A), TFE with perfluoro (propyl vinyl ether) ) available as PFA 6515N from DYNEON), a mixture of TFE, • hexafluoropropylene and vinylidene fluoride (commercially available with DYNEON THV 200G), etc.

It could be noted, however, that any conventionally available polymer, copolymer or mixture thereof which comprises a fluorinated polymer and that can be used to manufacture the valve for use in an inhaler according to the invention will be suitable. Examples of mixtures of polymers and / or copolymers comprise, for example, above 80% by weight of the fluorinated polymer, optionally above 40% by weight of the fluorinated polymer, optionally above 20% by weight of the fluorinated polymer or optionally above the fluorinated polymer. 5% by weight of the fluorinated polymer. Preferably, the fluorinated polymers selected from PTFE, PVF and PCTFE are used as mixtures with non-fluorinated polymers. For example a suitable material is the HOSTAFORM X329 ™ (Hoechst) which is a mixture of PTFE / acetal 5%, the HOSTAFORM C9021TF which is a mixture of PTFE / Acetal 20%, mixtures of PTFE / PBT (for example, LNP WL4040), mixtures of PTFE / PBT / silicone (for example, LNP WL4540).

The fluorinated polymers and mixtures thereof used in the invention can be molded in any conventional manner, for example, by injection molding, plastic molding etc.

According to a preferred aspect of the invention, the valve is a metering valve which comprises a metering chamber, a transfer passage through which a dose of substance to be dispersed can be passed from the container to the metering chamber, where the first position of the distribution passage is isolated from the dosing chamber and the dosing chamber is in communication with the container via the transfer passage, and in the second position the distribution passage is in communication with the dosing chamber and the transfer passage It is isolated from the dosing chamber.

The medicaments which can be administered in the aerosol formulations, suitably suspended in a liquid propellant, include any medicament useful in inhalation therapy which may be present in a form that is complete and substantially insoluble in the selected propellant system. The aerosol formulation, if desired, may comprise one or more active ingredients. Aerosols comprising two active ingredients in a conventional propellant system are known for the treatment of respiratory disorders such as asthma. The appropriate medicaments can thus be selected from, for example, analgesics, for example codeine, dihydromorphine, ergotamine, fentanyl or morphine; anginal preparations, for example dilithiazem; antiallergics, for example, cromolyn, cromoglycate or nedocromil; antibiotics, for example, cephalosporins, penicillins, strepomycin, sulfonamides or tetracyclines; antihistamines, for example metapyrylene; anti-inflammatories, for example beclomethasone, flunisolide, fluticasone, tipredane, budesonide, triamcinolone acetonide, antitussives, for example, noscapine; bronchodilators, for example ephedrine, epinephrine, fenoterol, formoterol, isoprenaline, isoproterenol, metaproternol, phenylephrine, phenylpropanolamine, pirbuterol, reporterol, rimiterol, salbutamol, salmeterol, terbutaline or (-) -4-amino-3,4-dichloro-at [ [6- [2- (2-pyridinyl) ethoxy] hexyl] amino] methyl] benzenemethanol; diuretics, for example, amiloride; anticloinergic, for example, ipratropium bromide; hormones, for example cortisone, hydrocortisone or prednisolone; and therapeutic proteins and peptides, for example glucagon or insulin. It will be clear to a person skilled in the art that, where appropriate, the medicaments will be used in the form of salts (eg, amine salts or alkali metals or acid addition salts) or as esters (eg, lower alkyl esters) ) or as solvates (for example hydrates) to optimize the activity and / or stability of the medicament and / or to minimize the solubility of the medicament in the propellant.

Preferably the medicament is selected from bronchodilators and anti-inflammatory steroids for use in the treatment of asthma by inhalation therapy, which include salbutamol (for example as sulfate), salmeterol (for example as the hydroxynaphthoate known as salmeterol xinafoate), beclomethasone dipropianate or a solvate thereof, fluticasone propionate or (-) -4-amino-3,5-dichloro-a- [[[6- [2- (pyrimidine) ethoxy] hexyl] amino] methyl] benzenemethanol and mixtures of the same.

The particle size of a particulate medicament can be such that it allows substantially all of the medicament to be inhaled upon administration to the lungs in the aerosol formulation and thus it will be desirable to be less than 20 microns, preferably in the range from 1 to 10 microns, for example from 1 to 5 microns. The particle size of the medicament or the medicament together with the excipient can be reduced by conventional means, for example by grinding, micronisation, spray drying or controlled recrystallization.

The final desirable aerosol formulation contains 0.0005-10% w / w / preferably 0.0005-5% w / w, especially 0.01-1.0% w / w, of drug relative to the total weight of the formulation.

Examples of aerosol propellants for aerosol formulations include CC12F2 (propellant 11) in admixture with CCL2F2 (propellant 12) CF2C1CF2C1 (propellant 14), however, due to the ozone depletion effects that are believed to be associated with such propellants, the valve for an aerosol container of the invention is more suitable if it is used with aerosol formulations which also comprise so-called "ozone-friendly" propellants.

Preferably, the propellants are selected from chlorofluorocarbons containing hydrogen and fluorocarbons and a number of medicinal aerosol formulations using such propellant systems have been described in, for example, EP 0372777, WO91 / 04011, W091 / 11173, W091 / 11495, W091 / 14422, WO92 / 00061, WO92 / 00062 and WO92 / 00107.

Suitable propellants include, for example, chlorofluorocarbons containing C hidrógeno _ hydrogen such as CH2C1F, CC1F2CHC1F, CF3CHCIF, CHF2CC1F2, CHC1FCHF2, CF3CH2C1 and CC1F2CH3; fluorocarbons containing C1-4 hydrogen such as CHF2CHF2, CF3CH2F, CHF2CH3 and CF3CHFCF3 and C1-4 perfluorocarbons such as CF3CF3 and.CF3CF2CF3.

Where the mixtures of fluorocarbons or chlorofluorocarbons containing hydrogen that are employed can be mixtures of the above-identified compounds or mixtures, preferably binary mixtures with other fluorocarbons or chlorofluorocarbons containing hydrogen for example A simple fluorocarbon or chlorofluorocarbon containing hydrogen can be used as a propellant. Particularly preferred as propellants are fluorocarbons containing hydrogen, especially 1, 1, 1,2, -tetrafluoroethane (CFCH2F) (propellant 134a) and 1, 1, 2, 3, 3, 3-heptafluoro-n-propane (CF3CHFCF3) (propellant 227) or a mixture thereof. The propellants are preferably used in the absence of excipients and adjuvants, such as solvents and surfactants. As used herein, "substantially free" refers to formulations which do not contain significant amounts of surfactants, for example, less than 0.0001% based on weight on the weight of the medicament. However, the invention also applies to formulations which include any conventionally used excipients, such as surfactants etc.

The formulations can be prepared by any conventionally known process, for example, by dispersing the medicament in the selected propellant in an appropriate container, for example, with the aid of sonication.

Preferably minimizing and avoiding the use of the formulation excipients for example, surfactants, co-solvents and so on in the aerosol formulations is advantageous since the formulations can be substantially tested and free of fragrance, less irritating and less toxic than conventional formulations.

However, such formulations are associated with a high degree of drug deposition in the valve components. The fluorinated valve according to the invention, particularly the valve having a fluorinated metering chamber, is preferably used to administer formulations. substantially free of excipients which have been found to substantially reduce the drug reservoir in the valve.

The formulations can be filled into suitable containers to release the pharmaceutical aerosol formulations. The containers generally comprise a container capable of withstanding the vapor pressure of the used propellant such as a plastic bottle or glass bottle coated with plastic or preferably a metallic cylindrical container, for example, an aluminum cylindrical container which can optionally be anodized , coated with a polymer or varnish and / or coated with plastic, wherein the container is closed with a valve according to the invention.

Conventional volume manufacturing methods and machinery are well known to those skilled in the art of manufacturing. pharmaceutical aerosol and can be used for the preparation of large-scale batches for the commercial production of filled containers. Thus, for example, in a volume manufacturing method a metering valve is molded into a cylindrical aluminum shaped container to form an empty container. The medication is added to the cargo container and the liquefied propellant is filled by pressure through the container into a container of manufacture. The suspension of the medicament is mixed before recirculation to a filling machine and an aliquot of the medicament suspension is then filled through the dosing valve into the container. Typically, in batches prepared for pharmaceutical use, each filled container is of appropriate weight, specified with a batch number and packaged in a tray for storage prior to the discharge test.

Each filled container should be conveniently placed in an appropriate piping device before being used to form a metered dose inhaler for administration of the drug into the lungs or nasal cavities of a patient. Suitable channeling devices comprise for example a valve activator and a passage in a conical or cylindrical shape through which the medicament can be released from the filled container via the metering valve to the nose or mouth of a patient, for example a nozzle activator. A separator can be placed between the passage and the nozzle. The metered dose inhalers are designed to deliver a fixed unit dose of medication by activation or "puff", for example in the range of 10 to 5000 micrograms of medication per breath.

According to a further aspect of the invention, other parts of the inhaler which are also susceptible to the drug reservoir may comprise the fluoropolymer of the invention and / or be coated with a fluorinated material according to the invention, for example, the activator in which the filled container comprises the valve is placed for application by the patient. All or part of the activator, for example, the valve activator, the nozzle activator and so on, may comprise the fluorinated polymer / copolymer or mixtures thereof and / or be coated with the fluorinated material.

The administration of the drug may be indicated by the treatment of moderate, severe or severe acute or chronic symptoms or for prophylactic treatment. It will be appreciated that the administration of the precise dose will depend on the age and condition of the patient, the particulate medication used and the frequency of administration will ultimately be at the discretion of the physician's assistant. When drug combinations are used, the dose of each component of the combination will generally be that used by each component when used alone. Typically, the administration can be one or more times, for example 1 to 8 times per day, giving for example 1,2, 3 or 4 puffs each time.

Each activation of the valve, for example, can release 25 μg, 50 μg, 100 μg, 200 μg or 250 μg of a medicine. Typically each filled container for use in a metered dose inhaler contains 60, 100, 120 or 200 measured doses of medication puffs.

The invention now further will be described with reference to the appended drawings wherein Figure 1 is a section of a metering valve according to the invention and which for the following Examples will serve to illustrate the invention but is not intended to be limiting.

A valve according to the invention is shown in Figure 1 and comprises a valve body 1 sealed in a bushing 2 by means of a hook, the bushing itself is placed on the neck of a container (not shown) with interposition of a package 3 in a well-known manner.

The body of the valve 1 is formed in its lower part with a metering chamber 4, and in its upper part with a sampling chamber 5 which also acts as a housing for a return spring 6. The metering chamber is made at least in part of a fluorinated polymer and / or a fluorinated coating according to the invention. The words "upper" and "lower" are used for the container when it is in an orientation of use with the neck of the container and the valve at the lower end of the container corresponding to the orientation of the valve as shown in Figure 1 Inside the valve body 1 is placed a valve stem 7, a part 8 in which it extends outwards from the valve through the seal of the lower stem 9 and the bushing 2. The part of the rod 8 is formed with an internal longitudinal or axial channel 10 open at its outer end of the rod and in communication with the radial passage 11. The upper portion of the rod 7 has a diameter such that it can slide through an opening of a seal of the upper rod and it will fit in the periphery of the opening enough to provide a seal. The seal of the upper rod 12 is held in position against a passage 13 formed in the body of the valve 1 between said upper and lower parts by a sleeve 14 which defines the metering chamber 4 between the seal of the lower rod and a seal of the upper stem 12. The stem of the valve 7 has a passage 15, which, when the rod is in the inoperative position shown, provides a communication between the metering chamber 4 and the sampling chamber 5, which communicates with the inside the vessel via a hole 26 formed in the side of the valve body 1.

The stem of the valve 7 is sloped down to the inoperative position by a return spring 6 and is provided with an edge 17 which butts against the seal of the lower rod 9 and the radial passage 11 opens downward the seal of the lower rod 9 so that the metering chamber 4 is isolated from the channel 10 and the inner suspension can not escape.

A ring 18 having a "U" shaped cross section extending in a radial direction is disposed about the valve body below the orifice 26 to form a conduit 19 around the valve body. As seen in Figure 1 the ring is formed as a separate component having an inner annular contact edge of a suitable diameter to provide proper friction on the upper part of the valve body 1, the ring seated against the passage 13 below the orifice 26. However, the ring 18 can alternatively be formed as an integrally molded part of the valve body 1.

To use the device the container is first agitated to homogenize the suspension within the container. The user then tightens the stem of the valve 7 against the force of the spring 6. When the valve stem is tightened - both ends of the passage 15 come to lie on the side of the seal of the upper rod 12 remote from the dosing chamber 4. this way a dose is measured inside the fluorinated metering chamber. Continuous depression of the valve stem will move the radial passage 11 in the metering chamber 4 while the seal of the upper rod 12 will seal against the body of the valve stem. In this way, the measured dose can exit through the radial passage 11 and the exit channel 10.

The release of the valve stem causes it to return to the illustrated position under the force of the spring 6. The passage 15 then provides a communication between the metering chamber 4 and the sampling chamber. Accordingly, this step of liquid state under pressure of the container through the orifice 26, through the passage 15 and from there to the metering chamber 4 to fill it.

In the following examples each aerosol contains a medicament suspension in an excipient-free propellant formulation. In each case the aerosols having conventionally available valves made of acetal or polyester are compared to the aerosols having valves according to the invention where either the dosing chamber is made of a fluorinated ethylene or polyester polymer which is plasma coated with CF4. In each case, the deposit of the medication generated through the use is measured and where the "Use through dose" collection regimens are carried out to analyze the doses administered during the life of the inhaler. The formulation tested in each case is an excipient-free propellant formulation comprising comprising fluticasone propionate and propellant 134a.

Method of reserving the medication in the valve.

- The amount of medication deposited in the valve is measured. The internal components of the valve include the dosing chamber, the upper stem seal and the upper and lower stem parts, which are on the dosing chamber. The deposit made at the beginning of the use of the inhaler (BOU), the manual and fire test 2 activations are taken down valve are followed by the manual activation 1 valve above to evacuate the dosing chamber. The deposit made in the inhalers at the end of the use (EOU) has used 120 activations of inhalers. Before the deposit made in these inhalers, the annual activation 1 valve below is taken followed by the manual activation 1 valve above to evacuate the dosing chamber.

The preparation of the samples to measure the valve reservoir is the same for both the BOU and EOU inhalers. First, the valve stem is washed with acetonitrile. Then, the inhaler is cooled for five minutes in a bath of dry ice and methanol. The valve is removed from the inhaler and the internal components of the valve are washed quantitatively with acetonitrile in a 50 ml volumetric flask containing 25 ml of water. The medicine solution is prepared by volume and the resulting solution tested by fluticasone propyanate by HPLC.

Dosing method The following method is used to evaluate the dosage for the different valve variants for each experiment. The dose is collected as pairs of activations in the BOU and EOU of the inhaler.

Before collection of the dose with BOU, manual activations and fire tests 2 are activated to drain the valve below. Activators 1 and 2 are activated in a dose trap. The dose trap is washed quantitatively with acetonitrile in a 100 ml volumetric flask containing 50 ml of water. The medicine solution is prepared by volume and the resulting solution tested by fluticasone propyanate by HPLC.

After the BOU collections, the inhalers have another 116 activations to spend. The inhalers are in EOU. Activations 119 and 120 are activated in a dose trap. The dose trap is washed quantitatively with acetonitrile in a 100 ml volumetric flask with 50 ml of water. The drug solution is prepared by volume and the resulting solution tested by propylate fluticasone by HPLC.

Example 1 The EOU inner valve reservoir and the dosing profile in the valves is investigated with different polymer metering chambers. The fluticasone / propellant propionate inhaler HFA134a, 50 micrograms, activation 120 is manufactured using the DF60 valve (acetal components, different polymer metering chambers and nylon ring). Inhalers are stored for a minimum of 2 weeks before the analysis of the valve medication reservoir. The deposit and dosing data are presented in Tables 1 and 2.

Table 1: Drug storage in the dosing chamber Table 2: Dosing data in activations 1 + 2/119 + 120 (for a 120 dose product) SD = standard deviation Table 2 demonstrates the improvement in the consistency of each dose administered and a reduction in the dose increase throughout the life of the inhaler using inhalers according to the invention.

Example 2 The reservoir of the EOU inner valve and the dosing profile in the valves is investigated with PTFE / acetal polymer dosing chambers. Fluticasone propylene / propellant inhalers HFA134a, 50 micrograms, activation 120 is manufactured using valve DF60 and valve DF60 modified with 5% PTFE / acetal in the dosing chamber. The inhalers "'are stored for a minimum of 2 weeks before the analysis." The deposit and dosing data are presented in Tables 3 and 4.

Table 3: Drug reservoir in the inner valve EOU The valve according to the invention shows a deposit of the inner valve significantly lower than that observed in the standard valves. This is due to the dosing chamber of the 5% PTFE / acetal polymer that has fluoride on the surface.

Table 4: Dosing data.

Several experiments are conducted to investigate the dose of the drug deposited in different types of polymer blocks.

The following method is used to analyze the dose of the drug deposited in the polymer blocks for each experiment. First, the propionate suspension of fluticasone is rapidly evacuated by penetration of the MDI cylindrical vessel. The valve is then cut from the MDI and the polymer block is carefully removed to be washed. The polymer block is washed quantitatively with acetonitrile in a 50 ml volumetric flask containing 25 ml of water. The medicine solution is prepared by volume and the resulting solution tested by fluticasone propyanate by HPLC.

Example 3 The effect of different polymers on the drug depot dose is investigated. The polymer blocks used have a standard injection molding finish. Polymer blocks are cut to an appropriate size to fill an 8 ml cylindrical inhaler container. The polymer blocks are then placed in the MDI containing a suspension of fluticasone propionate 0.35% w / w in 12 g of propellant HFA134a. The inhalers are stored for a minimum of 2 weeks before the analysis of the medication deposited in the polymer blocks. The results are presented in Tables 5 and 6.

Table 5: Effect of the polymer used in the drug reservoir Polymer used Amount of fluticasone propionate deposited Acetal 0.23 Hostaform C9021TF 0.15 (20% PTFE / acetal mixture) THV200G 0.14 (TFE, HFP, vinylidene fluoride) THV500G 0.09 (TFE, HFP, vilidene fluoride) PFA6515N 0.05 (perfluoroalkyl) FEP6107 0.04 Fluorinated ethylenepropylene) ETFE ET6125 0.04 (ethylenetetrafluoroethylene) Table 6: Effect of the polymer used in the drug reservoir The addition of PTFE to polyester reduces the deposit of fluticasone significantly compared to pure polyester.

The lowest levels of drug deposition are observed with the polymers with the highest levels of fluorination (PFA, ETFE, and FEP).

Example 4 The effect of the fluorine coating on the polymer and the dose of the drug deposited is investigated. The acetal is the polymer coated with fluorine. The coating processes are conventionally known plasma coating processes.

The polymer blocks are cut to an appropriate size to fill an 8 ml cylindrical inhaler container. The polymer blocks are then placed in an MDI containing a suspension of fluticasone propionate 0.34% w / w in 12 g of propellant HFA134a. The inhalers are stored for a minimum of 2 weeks before the analysis of the medication deposited in the polymer blocks. The results are presented in Table 7.

Table 7: Effect of the fluoride coating on the drug reservoir The fluorination of the surface of the acetal by the coating has reduced the drug reservoir significantly compared to the acetal which does not have a fluorinated coating.

It is understood that the present disclosure is for purposes of illustration only and the invention extends to modifications, variations and improvements for this which will be within the ordinary skills of the person skilled in the art.

It is noted that in relation to this date that in relation to this date, the best method known by the applicant to implement the aforementioned invention, is that which is clear from the manufacture of the objects to which the same refer. Having described the invention as above, being claimed as property contained in the following:

Claims (10)

1. The valve for an aerosol container for distributing a suspension or solution characterized in that it comprises a substance in a liquid propellant contained therein further optionally comprises conventionally used excipients, wherein the valve comprises a valve body defining a chamber, a transfer passage wherein a dose of substance to be dispersed can pass from the container to the chamber, and the distribution medium which enables the substance to be dispersed, wherein the chamber comprises a fluorinated polymer.

2. The valve according to claim 1 characterized in that the chamber is a metering chamber for use in an aerosol container which a metered dose inhaler.

3. The valve according to claim 1 or 2 characterized in that the chamber is made of a plastic material which comprises at least 5% of the fluorinated polymer.

4. The valve according to claim 1 or 2 characterized in that a part of the entire surface of said chamber which is in contact with the substance to be distributed is coated with a fluorinated material.

5. The valve according to claim 4 characterized in that the coating is a coating of CF4 coated with plasma.

6. The valve according to any of claims 1 to 5 characterized in that the substance to be delivered is a medicament suspended in propellants selected from liquefied HFA 134a, 227 or a mixture thereof.

7. The valve according to claim 6 characterized in that the propellants are substantially free of adjuvants.

8. The valve according to claim 6 or 7 characterized in that the medicament is selected from fluticasone propionate, salbutamol, beclomethasone dipropianate, salmeterol, pharmaceutically acceptable salts, solvents or esters thereof and mixtures thereof.

9. The aerosol container characterized in that it comprises a valve according to any of claims 1 to 8.

10. The inhalation device characterized in that it comprises an aerosol container according to the ss? indication 9.