MXPA00003103A - Stabilized preparations for use in nebulizers - Google Patents

Abstract

Stabilized dispersions are provided for the delivery of a bioactive agent to the respiratory tract of a patient. The dispersions preferably comprise a stabilized colloidal system which may comprise a fluorochemical component. In particularly preferred embodiments, the stabilized dispersions comprises perforated microstructures dispersed in a fluorochemical suspension medium. As density variations between the suspended particles and suspension medium are minimized and attractive forces between microstructures are attenuated, the disclosed dispersions are particularly resistant to degradation, such as by settling or flocculation. In particularly preferred embodiments, the stabilized dispersions may be administered to the lung of a patient using a nebulizer.

Description

PREPARATIONS STABILIZED FOR USE IN NEBULIZERS Field of the Invention The present invention generally relates to formulations and methods for the administration to a patient, via the respiratory apparatus, of bioactive agents. More particularly, the present invention relates to methods, systems and compositions comprising relatively stable dispersions, which are preferably administered via nebulization, both in the form of topical delivery to the lung and in the form of delivery to the circulatory system through the lung.

Background of the Invention The means of scheduled administration of the drug are particularly desirable where the toxicity or bioavailability of the pharmaceutical compound is a problem. Delivery methods and specific drug compositions that effectively deposit the compound at the site of action potentially serve to minimize toxic side effects, decreasing dosage requirements and lowering therapeutic costs. The development of such systems for the supply of pulmonary drugs has been a goal for the pharmaceutical industry. They are dry powder inhalers (DPIs), metered dose inhalers (MDIs) and nebulizers. IDMs, the most popular method of administration by inhalation, can be used to administer medications in soluble form or as a dispersion. Normally the IDMs comprise a Freon or other relatively high vapor pressure propellant, which reinforces the aerosolized medication inside the respiratory device at the moment of the activation of the device. Unlike IDMs, IPSs generally depend on the patient's inspiratory efforts to introduce a drug in the form of a dry powder to the lungs. Finally, the nebulizers form an aerosol of medication to be inhaled, imparting energy to a liquid solution. More recently, drug administration has also been explored directly to the lungs, using a fluorochemical medium, during liquid ventilation or lavage of the lungs. Although each of these methods and associated systems can prove their effectiveness in selected situations, the inherent disadvantages, including limitations in the formulation, may limit their use. The need for new drugs for the lungs derived from biotechnology (for example, peptides, proteins, oligonucleotides and plasmas), has been a key development, which has raised the importance of drug delivery systems to the lungs. The systemic administration of these biopolymers has demonstrated the difficulty of their large molecular size, superior surface change, poor chemical and enzymatic stability, low penetration through various body absorption barriers. Due to their low bioavailability through oral and transdermal administration routes, drugs such as peptides are currently administered mainly by infusions or frequent injections. The development of less invasive methods for administering peptides and other polymers represents a major focus for current drug administration research and a large number of administration sites, including oral, nasal and pulmonary administration, are still being explored. . As indicated above, nebulizers are frequently used to administer drugs in human lungs and are particularly useful for the treatment of inpatients or outpatients. There are two main types of apparatus: air jet nebulizers and ultrasonic nebulizers. In air jet nebulizers, compressed air is pushed through a hole. Subsequently a liquid can be isolated from a perpendicular nozzle (The Bernoulli effect) to mix it with the air jet to form droplets. A deflector (or series of deflectors) is used inside the nebulizer, in order to facilitate the formation of the aerosol cloud, in contrast, the ultrasonic nebulizers depend on the generation of ultrasonic waves in an ultrasonic nebulizer chamber, through a ceramic piezoelectric crystal that vibrates at a precise frequency when it is electrically agitated. The ultrasonic energy prepares the high energy waves in the nebulizer solution, facilitating the generation of an aerosol cloud. Typically, the formulations for nebulization comprise water-based solutions. Assuming that the solubility and stability of the active drug is adequate, when the estimated minimum effective dose exceeds approximately 200 μg, administration via nebulization of a water-based formulation is reasonable. For a long time, continuous nebulization has been an option for topical administration of pulmonary therapy, for the treatment of various lung diseases, such as asthma, chronic lung obstructive diseases, episema and bronchitis. More recently, proteins such as DNSA, have been administered through conventional jet nebulizers, for their local effect in the lung. Unfortunately, continuous nebulization is an intrinsically deficient way to administer medications in the form of an aerosol. This is underlined by the fact that the doses of bronchodilators administered using nebulizers are of a magnitude three times greater than a bioequivalent dose administered by means of an IDM generator or dry powder. In addition to concerns regarding the efficiency of the apparatus, there are also concerns regarding changes in formulation during the nebulization process. For example, over time the concentration of drug in the solution of the container of an air jet nebulizer often increases. In addition, a change in drug concentration may involve a change in the osmolarity of the aqueous solution and it has been shown that hyperosmolar nebulizing solutions cause bronchoconstriction. In terms of pulmonary administration of bioactive agents to the systemic circulation via nebulization, most of the investigations are focused on the use of portable ultrasonic nebulizers, also referred to as nebulizers of measured solution. These devices should not be confused with portable nebulizers that require several minutes per treatment. These devices, generally known as simple bolus nebulizers, aerosolize a bolus of simple medication in an aqueous solution with an efficient particle size to be administered, in one or two breaths, deep in the lungs. These devices fall into three well-defined categories. The first category comprises pure piezoelectric simple bolus nebulizers, such as those described by Müitterlein, and associates, (J. Aerosol Med. 1988; 1: 231). In another category, the desired aerosol cloud can be generated by simple microchannel extrusion bolus nebulizers, such as those described in US Patent No. 3,812,854. Finally, a third category comprises apparatuses exemplified by Robertson, and associates, (W092 / 11050), wherein simple bolus nebulizers are described by cyclic pressurization. Each of the references mentioned above is incorporated in its entirety in the present invention as a reference. Although such devices are an improvement for conventional portable nebulizers that require a treatment time of several minutes, they are limited by the fact that they employ multiple dose containers. This is problematic for protein administration applications, where the product must remain sterile through the therapy program. The use of at least these multiple dose containers, would require the use of preservatives and it is still probable that this method is not satisfactory in all the use scenarios of the products. In order to overcome some of these limitations, Schuster, et al. (Pharm. Res. 1997: 14: 354, which is incorporated herein by reference) recently described a unit dosage system. However, even with such unit dosing systems the problems remain. For example, a difficulty with the apparatuses for the administration of bioactive agents to the systemic circulation, is that the bioactive agent must have a great thermal stability in an aqueous phase. This is possible only to select some peptides and proteins. Therefore, it is an object of the present invention to provide methods, compositions and systems for the effective pulmonary administration of bioactive agents using nebulizers.

Additionally it is an object of the present invention to provide methods and compositions for the stabilization of bioactive agents that will be administered using a nebulizer. It is still an object of the present invention to provide methods and preparations that allow to administer with advantages, bioactive agents to the systemic circulation of a patient who needs them.

Summary of the Invention These and other objects are provided by means of the description and claims of the present invention. For this purpose, the methods and associated compositions of the present invention provide, in a broad sense, the improved administration of bioactive agents using stabilized preparations. Preferably, the bioactive agents of a patient through the respiratory system. More particularly, the present invention provides for the formation and use of stabilized dispersions (also referred to as stabilized respiratory dispersions) and inhalation systems, including nebulizers comprising said dispersions, as well as individual components thereof. Unlike the form of use in nebulizers of the formulations of the prior art, the present invention preferably employs new techniques to reduce the attractive forces between the dispersed constituents and, in order to reduce density fluctuations in the stabilized dispersion, where the degradation of the preparations described by flocculation, sedimentation or cremation. In addition, the stabilized preparations of the present invention preferably comprise a suspension medium which further serves to reduce the degradation range with respect to the incorporated bioactive agent. In particularly preferred embodiments, the suspension medium will comprise a fluorocarbon or fluorocarbon compound. Those skilled in the art will appreciate that, the stable preparations described and the systems comprising such preparations, act to reduce the inadequate dosage, thereby facilitating a uniform drug administration, allowing more concentrated dispersions and, retarding the degradation of any of the labile biopolymers incorporated in the present invention. In a broad sense, the stabilized dispersions of the present invention incorporate colloidal preparations comprising a non-aqueous continuous phase, wherein the stabilized dispersions have the ability to be nebulized or aerozolized to provide effective dosing to a patient in need thereof. For example, the stabilized dispersions may comprise any inverted emulsion or particulate dispersion that allows for the effective administration of a bioactive agent for the passage of air to the lungs of a mammal. Those skilled in the art will appreciate that, the dispersion phase of said preparations may comprise liquid particles in the case of inverse emulsions or non-liquid particles in the case of stabilized suspensions. Therefore, for the purposes of the present application, the term "stabilized dispersion" should be maintained to include colloidal systems comprising inverse emulsions and particulate suspensions, unless otherwise indicated by contextual constraints. With respect to each of these cases, the stabilized dispersion can be administered with a nebulizer, to provide the aerosolized medicament during pulmonary administration.

With respect to the particularly preferred embodiments, the stabilized preparations of the present invention provide these and other advantages through the use of particulate suspensions comprising hollow and / or porous perforated microstructures, which substantially reduce molecular attractive forces, such as van del Waals forces, which dominate the dispersal preparations of prior art. More particularly, the use of perforated (or porous) microstructures or microparticles that are penetrated or filled with the medium of the surrounding fluid or, suspension medium, significantly reduces the breakdown of attractive forces between the particles. Additionally, the components of the dispersions can be selected to minimize differences in polarity (e.g., reduced constant Hamaker differences) and additionally stabilize the preparation. The relatively homogeneous nature of these particulate dispersions or suspensions inhibits deterioration, thereby allowing the preparations to have improved stability. In addition to the advantages not hitherto appreciated, associated with the formation of stabilized particulate dispersions, the perforated configuration and the corresponding large surface area, makes the microstructures more easily transported through the gas flow during inhalation, than the particles unperforated of comparable size. This in turn, makes it possible for the perforated micro-structures or microparticles of the present invention to be transported more efficiently in the lungs of a patient, than non-perforated structures, such as micronized particles or relatively non-porous microspheres. In view of these advantages, the dispersions comprising perforated microstructures are particularly compatible with inhalation therapies comprising the administration to at least a part of the pulmonary air duct, of the bioactive preparation. For the purposes of the present application, these stabilized dispersions directed to the administration of pulmonary drug may be conditioned respiratory dispersions. In particular, preferred embodiments such as respiratory dispersions, are used in conjunction with nebulizers, to effectively deliver a bioactive agent to the pulmonary air passages or nasal passages of a patient. For those embodiments that comprise perforated microstructures, those skilled in the art will appreciate that they may be formed of any biocompatible material that provides the desired physical or morphological characteristics, enabling the preparation of stabilized dispersions. With respect to this, the perforated microstructures comprise pores, voids, defects or other interstitial spaces that allow the fluid suspension means to freely penetrate or introduce the particulate boundaries, thereby reducing or minimizing the density differences between the components of dispersion. Even given these restrictions, it will be appreciated that any material or configuration can be used to form the matrix of the microstructure. With respect to the selected materials, it is desirable that the microstructure incorporates at least one surfactant. Preferably, this surfactant will comprise a phospholipid or other surfactant approved for use in the lungs. As the configuration, the particularly preferred embodiments of the present invention incorporate hollow sprinkle-dried microspheres, which have a relatively thin, porous wall defining a large internal void, although another contained void or perforated structures is also contemplated. Therefore, the selected embodiments of the present invention provide stable respiratory dispersions for use in a nebulizer, comprising a suspension medium that substantially penetrates said perforated microstructures. Although preferred embodiments of the present invention comprise perforated microstructures, relatively non-porous or solid particulates may also be used to prepare dispersions that are compatible with the teachings of the present invention. That is, respiratory dispersions comprising suspensions of relatively non-porous particulates or solids in a non-aqueous suspension medium, are also contemplated to be within the scope of the present invention. Therefore, the term "particulate", as used in the present invention, should be broadly construed to mean any non-liquid particle comprising the discontinuous phase of a dispersion or suspension. More specifically, it will be appreciated that the term "particulate" should be maintained to contain particles of any porosity, including both perforated microstructures and relatively non-porous particles. It should be further appreciated that the non-aqueous continuous phase or suspension medium can be any liquid or compound that is in liquid form, under suitable thermodynamic conditions, for the formation of a compatible particulate dispersion or inverse emulsion. Unless otherwise indicated by the contextual constraints, the terms "means of suspension", "means of suspension" and "non-aqueous continuous phase" are maintained to be equivalent for the purposes of the present application and may be used. indistinctly. For embodiments wherein the stabilized dispersion is to be used in conjunction with a nebulizer, the suspension medium preferably comprises hydrocarbons or fluorocarbons having a vapor pressure of less than about one atmosphere. That is, it will be preferable that it be a liquid under standard conditions of one atmosphere and at a temperature of 25 ° C. In accordance with the teachings contained in the present invention, the particularly preferred non-aqueous suspension means or suspension phases comprise fluorochemicals (eg, perfluorocarbons or fluorocarbons) which are liquid at room temperature. It is well established that many fluorochemicals have a proven history or safety and biocompatibility in the lung. Additionally, in contrast to aqueous solutions, fluorochemicals do not adversely affect gas exchange. In addition, because of their unique moisture characteristics, fluorochemicals may have the ability to transport an aerosolized stream of particles to a greater depth in the lung, thus improving systemic administration. Finally, many fluorochemicals are also bacteriostatic, thus decreasing the potential for microbial growth in compatible nebulizer devices. Therefore, the present invention provides the use of a fluorochemical liquid in the manufacture of a medicament for the pulmonary administration of a bioactive agent, wherein the medicament comprises a stabilized dispersion having a continuous fluorochemical phase, which is nebulized using a nebulizer, to form an aerosolized medicament comprising said bioactive agent, whereby said aerosolized medicament is administered to at least a portion of the pulmonary air passages of a patient in need thereof. Additionally it will be appreciated that, in the selected embodiments, the present invention comprises methods for the formation of dispersions comprising the combination of a plurality of particulates comprising at least one bioactive agent with a predetermined volume of the suspension medium, to provide a mixture respiratory Subsequently, the respiratory mixture can be mixed or stirred to provide a substantially homogeneous dispersion. Again, in the preferred embodiments, the particulates will comprise perforated microstructures which allow the introduction or penetration of the selected suspension medium. Of course, in other embodiments the dispersion may comprise an inverse emulsion. Therefore, the preferred embodiments of the present invention provide for the formation of stabilized respiratory dispersions, comprising the steps of: combining a plurality of perforated microstructures comprising at least one bioactive agent with a predetermined volume of a suspension medium not watery, to provide a respiratory mixture, wherein said suspension medium penetrates said perforated microstructures; and mixing process of said mixture to provide a substantially homogeneous respiratory dispersion. Together with the aforementioned advantages, the stability of the formed particulate dispersions can additionally be decreased by reducing, or minimizing, the Hamaker constant differential between incorporated particulates or perforated microstructures and the suspension medium. Those skilled in the art will appreciate that the Hamaker constants tend to rise with the indices. With respect to this, the present invention further provides methods for stabilizing a respiratory dispersion, reducing the van der Waals attractive forces, comprising the steps of: providing a plurality of perforated microstructures; combining the perforated microstructures with a suspension medium comprising at least one fluorochemical, wherein the suspension medium and the perforated microstructures are selected to provide a differential value of the refractive index of less than about 0.5. In accordance with the teachings of the present invention, the particulates preferably comprise perforated microstructures and, in the particularly preferred embodiments, the particulates will comprise hollow, porous microspheres. With respect to the administration of the stabilized preparations, another aspect of the present invention is directed to liquid inhalation systems for administering to the patient one or more bioactive agents. Therefore, the present invention provides inhalation systems for the pulmonary administration to a patient of a bioactive agent, comprising: a container for fluid; a stable respiratory dispersion in said fluid container, wherein said stabilized dispersion comprises a continuous fluorochemical phase and at least one bioactive agent; and a nebulizer operably associated with said fluid container, wherein the nebulizer has the ability to aerosolize and discharge stable respiratory dispersion. The respiratory dispersion may comprise an inverse emulsion, micro-emulsion or particulate suspension. Preferably, the dispersion comprises a suspension medium having dispersed therein a plurality of perforated microstructures, which comprise at least one bioactive agent and are substantially penetrated by the suspension medium. Those skilled in the art will appreciate that the nebulizer may comprise an ultrasonic nebulizer, an air jet nebulizer and, more preferably, a simple bolus nebulizer. In any case, the systems described in the present invention allow the reproducible administration of bioactive agents having aerosolized particles, of small enough size to travel deep into the lung. More specifically, the aerosolized medicament will preferably exhibit a fraction of fine particles greater than about 20% w / w. Yet another associated advantage of the present invention is the effective pulmonary administration of bioactive agents. As used in the present invention, the term "bioactive agent" refers to a substance which is used with an application that is therapeutic or diagnostic in nature, such as methods for diagnosing the presence or absence of a disease in a patient and / or methods for the treatment of a patient's disease. In the same way as compatible bioactive agents, those skilled in the art will appreciate that any therapeutic or diagnostic agent can be incorporated into the stabilized dispersions of the present invention. For example, the bioactive agent must be selected from the group consisting of anti-allergens, bronchodilators, bronchoconstrictors, pulmonary surfactants, analgesics, antibiotics, leukotriene inhibitors or antagonists, anticholinergics, mast cell inhibitors, antistamines., anti-inflammatories, antineoplastic, anesthetics, anti-tuberculosis, imaging agents, cardiovascular agents, enzymes, steroids, genetic material, viral vectors, anti-perception agents, proteins, peptides and combinations thereof. Particularly preferred bioactive agents comprise compounds that are to be administered systemically (eg, to the systemic circulation of a patient), such as peptides, proteins and polynucleotides. As will be described in more detail below, the bioactive agent can be incorporated, mixed, coated or otherwise associated with the perforated microstructure. In other embodiments, the bioactive agent may be associated with the dispersion phase (eg, aqueous phase) of an inverse emulsion. For any form of stabilized dispersion that is employed, the present invention provides methods for the pulmonary administration of one or more bioactive agents comprising the steps of: providing a stabilized respiratory dispersion comprising one or more bioactive agents wherein the respiratory dispersion comprises a continuous fluorochemical phase; misting said respiratory dispersion with a nebulizer, to provide an aerosolized medicament; and administering a therapeutically effective amount of said aerosolized medicament to at least a portion of the pulmonary conduits of a patient in need thereof. When the stabilized dispersion comprises an inverse emulsion, the bioactive agent will preferably be substantially associated with the dispersed drops. With respect to the particulate dispersions, the selected bioactive agent or agents can be used as the only structural component of the particulate or perforated microstructures. On the contrary, the particulate or perforated microstructures may comprise one or more components (for example, structural materials, surfactants, excipients, etc.), in addition to the incorporated bioactive agents. In the particularly preferred embodiments, the suspended or perforated particulate microstructures will comprise relatively high concentrations of surfactant (greater than about 10% w / w) together with the incorporated bioactive agent (s). Finally, it should be appreciated that the particulate or perforated microstructures may be covered, linked or otherwise associated with the bioactive agent in non-integral form. In any configuration that is selected, it will be appreciated that the associated bioactive agent can be used in its natural form, or in the form of one or more salts known in the art. In addition to the inverse emulsions and suspensions of perforated microstructures, it should be emphasized that the present invention provides nebulization and pulmonary administration of relatively stable particulate dispersions. Those skilled in the art will appreciate that, due to other physiochemical characteristics, the morphology of the incorporated particulates can vary without destabilizing the dispersion. Therefore, the stabilized dispersions can be formed with compatible paratylates even if they exhibit relatively low porosity, or if they are substantially solid. Therefore, while the particularly preferred embodiments of the present invention will comprise perforated microstructures or microspheres, acceptable dispersions can be formed using particulates of relatively low porosity, such as nanocrystals or micronized drugs. With respect to this, said embodiments are specifically contemplated to be within the scope of the present invention. The stabilized dispersions of the present invention may optionally comprise one or more additives to further improve stability or increase biocompatibility. For example, various surfactants, co-solvents, osmotic agents, stabilizers, chelators, buffers, viscosity modulators, solubility modifiers and salts may be associated with the perforated microstructure, suspension medium or both. The use of such additives will be understood by those of ordinary skill in the art and, the specific amounts, proportions and types of agents, can be determined empirically without undue experimentation. Other objects, features and advantages of the present invention will be apparent to those skilled in the art, from a consideration of the following detailed description of the preferred exemplary embodiments thereof.Brief Description of the Drawings Figures 1A1 through 1 F2 illustrate changes in particle morphology as a function of variation in the ratio of a fluorocarbon blowing agent to the phospholipid (PFC / CP) that is present in the spray dried food. Micrographs produced using an electron scanning microscope and microscopic electron transmission techniques, show that in the absence of FCs, or in low proportions of PFC / PC, the resulting spray-dried microstructures comprising gentamicin sulfate, are neither hollow nor porous. On the contrary, in high proportions of PFC / PC, the particles containing numerous pores are substantially hollow with thin walls. Figure 2 is a microscopic electron scanning image of the perforated microstructures, which comprise cromolyn sodium illustrating a preferred hollow / porous morphology. Figure 3 shows the results of in-vitro studies of the Adersen cascade impactor, comparing the same hollow porous cromolyn sodium formulation, administered via MDI in HFA-134a, or from a long-chain fluorocarbon (perfluorooctyl ethane) ), via nebulization. It is observed that the nebulized particles deposited on the previous stages in the impactor correspond to the improved in-vivo systemic administration.

Detailed Description of the Preferred Modes Although the present invention can be embodied in different forms, what is described herein are specific illustrative embodiments thereof, which exemplify the principles of the present invention. It should be emphasized that the present invention is not limited to the specific embodiments illustrated. As stated above, the present invention provides systems, methods and compositions that allow the formation and administration of stabilized suspensions or dispersions, having a non-aqueous continuous phase, which can be advantageously used during the pulmonary administration of bioactive agents, in set with a nebulizer. With respect to this, it will be appreciated that the stabilized dispersants can comprise any colloidal system, including, inverse emulsions, microemulsions or particulate dispersions (eg, non-liquid particles), which can be nebulized to effectively deliver, to the air ducts pulmonary of a patient, a bioactive agent. Particularly preferred embodiments comprise stabilized dispersions that incorporate a liquid fluorochemical continuous phase or a suspension medium. In any case, the stabilized dispersion will be administered to the pulmonary air passages of a patient, preferably using a nebulizer (for example a simple bolus nebulizer). Traditional fogging preparations of the prior art usually comprise aqueous solutions of the pharmaceutically selected compound. It has been established for a long time that with such prior art nebulizing preparations, the corruption of the incorporated therapeutic compound can severely reduce the efficiency. For example, with conventional multi-dose aqueous mist preparations, bacterial contamination is a constant problem. In addition, the solubilized medicament may precipitate out or degrade over time, adversely affecting the administration profile. This is particularly true in larger and labile polymers, such as enzymes or other types of proteins. The precipitation of the incorporated bioactive agent can lead to the growth of the particle, which results in a substantial reduction in the penetration of the lung and a corresponding decrease in bioavailability. This incongruent dosage significantly reduces the effectiveness of any treatment. The present invention overcomes these and other difficulties, providing stabilized dispersions with a non-aqueous continuous phase, preferably comprising a fluorinated compound (eg, fluorochemical, fluorocarbon or perfluorocarbon). Particularly preferred embodiments of the present invention comprise fluorochemicals which are liquid at room temperature. As indicated above, the use of such compounds, either as a continuous phase or as a suspension medium, provide some advantages over the liquid inhalation preparations of the prior art. With respect to this, it is well established that many fluorochemicals have a proven safety and biocompatibility history in the lung. Additionally, in contrast to aqueous solutions, fluorochemicals do not negatively affect gas exchange, following pulmonary administration. On the contrary, they may currently have the ability to improve gas exchange and, because of their unique moisture characteristics, may have the ability to transport more deeply a stream of aerosolized particles to the lung, thereby improving the systemic administration of the desired pharmaceutical compounds. In addition, the relatively non-reactive nature of the fluorochemicals acts to retard any degradation of an incorporated bioactive agent. Finally, many fluorochemicals are also bacteriostatic, thus decreasing the potential for microbial growth in compatible nebulizer devices. As previously indicated, the present invention may comprise any number of colloidal systems including, but not limited to, inverse emulsions, microemulsions and particulate dispersions. For purposes of application, the terms shall be used in accordance with their common meanings, unless otherwise indicated in the contextual restrictions. Therefore, those skilled in the art will appreciate that emulsions (whether micro or inverse (oil in water)), will comprise a dispersion of liquid particulates in a liquid continuous phase. In contrast, a particulate suspension or dispersion should, as used in the present invention, be maintained to comprise a distribution of non-liquid particles in a liquid continuous phase or suspension medium. Although inhalation preparations compatible with the present invention may comprise any colloidal system, which has the ability to nebulize or aerosolize, the following commentary, for purposes of explanation, will be directed in large part to the particularly recited embodiments of the present invention, which they comprise stabilized particulate dispersions. It should be emphasized that the scope and content of the present invention is not limited to these specific illustrative modalities and, in particular, is not limited to those embodiments comprising particulate dispersions. Although such dispersions are particularly effective in terms of stability and lung distribution, nebulized inverse emulsions may also be provided during the efficient pulmonary delivery of bioactive compounds. Therefore, its use is specifically contemplated to be within the scope of the present invention. With respect to the particulate dispersions, the improved stability provided by the suspensions of the present invention can be improved by decreasing the van der Waals attractive forces between the suspended particles and by reducing the differences in density between the suspension medium and the particles. According to the teachings described herein, the increases in suspension stability can be imparted by engineering perforated microstructures, which are then dispersed in a compatible suspension medium. In this regard, the perforated microstructures comprise pores, voids, voids, defects or other interstitial spaces that allow the fluid suspension medium to penetrate or freely enter the particulate boundaries. Particularly preferred embodiments comprise perforated microstructures that are both hollow and porous, almost honeycomb-like or sponge-like in appearance. In the especially preferred embodiments, the perforated microstructures comprise hollow and porous spray dried microspheres. When the perforated microstructures are placed in the suspension means, the suspension means has the ability to penetrate the particles, so they create a "homodispersion", where both the continuous and dispersed phases are essentially indistinct. Because the defined or "virtual" particles (for example comprising the volume circumscribed by the matrix of the microstructure), are incorporated almost in all the medium in which they are suspended, the driving forces of particle aggregation are minimized ( flocculation). Additionally, the differences in density between the defined or virtual particles and the continuous phase are minimized, with the microstructures full of the medium, so that the cremation or sedimentation of particles is effectively reduced. Therefore, the stabilized suspensions of the present invention are particularly compatible with inhalation therapies and can be used in conjunction with metered dose inhalers (MDIs), dry powder inhalers and nebulizers. More specifically, the particulate suspensions of the present invention can be designed to decrease the attractive forces between the particles. Flocculation driving the main forces in non-aqueous media are attractive forces van der Waals. The van der Waals forces are of quantum mechanical origin and can be visualized as attractions between fluctuation dipoles (for example induced dipole-induced dipole interactions). The dispersion forces are extremely short range and rise as the sixth power of the distance between the atoms. When two macroscopic bodies reach each other, scatter attractions between the atoms are added together. The resulting force is of considerably longer range and it depends on the geometry of the interaction bodies. More specifically, for two spherical particles, the magnitude of the van der Walls potential, VA, can be approximated by, where Aeff is the effective Hamaker constant which counts the nature of the particles and the medium, Ho is the distance between the particles and R- \ and R2, is the radius of the spherical particles 1 and 2. The effective Hamaker constant is proportional to the difference in the polarities of the particles dispersed in the suspension medium: AtSf =. { ^ A ^ - ArA? T) ', where ASM and APART are the Hamaker constants for the suspension medium and the particles respectively. Since the suspended particles and the dispersion medium become similar in nature, ASM and APARt become closer in their magnitude and Aeff and VA, become smaller. That is, by reducing the differences between the Hamaker constant associated with the suspension medium and the Hamaker constant associated with the scattered particles, the effective Hamaker constant (and corresponding to the van der Waals attractive forces) can be reduced. As noted above, one way to minimize differences in Hamaker constants is to create a "homodispersion," which is both the continuous and the scattered essentially indistinct phases. In addition to exploiting the morphology of the particles to reduce the effective Hamaker constant, the components of the structural matrix (which defines the perforated microstructures) will preferably be chosen to exhibit a Hamaker constant relatively close to that of the selected suspension medium. With respect to this, one of the components can use the actual values of the Hamaker constants of the suspension medium and the particulate components, to determine the compatibility of the dispersion ingredients and to provide a good indication for the stability of the preparation. Alternatively, one of these components could select the relatively compatible perforated microstructure components and the suspension means, using rapidly distinguishable characteristic physical values that match the Hamaker measurement constants.

With respect to this, it has been found that the refractive index values of many compounds tend to rise with the corresponding Hamaker constant. Therefore, easily measurable refractive index values can be used, to provide a fairly good indication, for such a combination of the suspension medium and particulate excipients, to provide a dispersion having a relatively low effective Hamaker constant and an associated stability . It will be appreciated that, because the refractive indices of the compounds are widely available or are easily derived, the use of such values allows the formation of stabilized dispersions according to the present invention, without undue experimentation. For illustrative purposes only, in Table 1 below, the refractive indices of various compounds compatible with the dispersions described are shown, Table 1 Refractive index compound HFA-134a 1,172 HFA-227 1,223 CFC-12 1,287 CFC-114 1,288 PFOB 1,305 Mannitol 1,333 Ethanol 1,361 n-octane 1,397 DMPC 1.43 F-68 Pluronic 1.43 Sucrose 1,538 Hydroxyethyl starch 1.54 Sodium chloride 1,544 Consistent with the compatible dispersion components set forth above, those skilled in the art will appreciate that dispersions are formed where the components have a refractive index differential of less than about 0.5. That is, the refractive index of the suspension medium will preferably be within about 0.5 of the refractive index associated with the suspended particles or perforated microstructures. Additionally it will be appreciated that, the refractive index of the suspension medium and the particles can be measured directly or roughly, using the refractive indices of the main component in each respective phase. For perforated particles or microstructures, the main component can be determined by a weight percentage basis. For the suspension medium, the main component will normally be derived from a volume percentage basis. In the selected embodiments of the present invention, the differential value of the refractive index will preferably be less than about 0.45, about 0.4, about 0.35 or even less than 0.3. Given the lower refractive index differentials involving greater dispersion stability, the particularly preferred embodiments comprise index differentials less than about 0.28, about 0.35, about 0.2, about 0.15, or even less than about 0.1. It is pointed out that an expert in the art will have the ability to determine which of the dispersion components are particularly compatible without undue experimentation. The last choice of preferred components will also be influenced by other factors, including biocompatibility, regulatory status, ease of manufacture and cost. In contrast to prior art attempts to provide stabilized suspensions requiring surfactants that are soluble in the suspension medium, the present invention can provide stabilized dispersions, at least in part, by immobilizing the bioactive agent (s) within the matrix of hollow, porous microstructures. Therefore, the preferred useful excipients in the present invention are substantially insoluble in the suspension medium. Under such conditions, even surfactant-like ones, such as for example lecithin, can not be considered to have surfactant properties in the present invention, since the performance of a surfactant requires amphiphilic to be reasonably soluble in the suspension medium. The use of insoluble excipients also reduces the potential for particle growth by Ostwald maturation. As noted above, the minimization of density differences between the particles and the continuous phase, can be improved by the perforated and / or hollow nature of the incorporated microstructures, so that the suspension medium constitutes the bulk of the volume of the particle. As used in the present invention, the term "particle volume" corresponds to the volume of the suspension medium that would be displaced by the incorporated hollow / porous particles, if these were solid, for example the volume defined by the limit of the particle. For purposes of explanation, these particulate volumes filled with fluid can be referred to as "virtual particles". Preferably, the average volume of the bioactive agent and / or layer or matrix of the excipient (eg, the volume of the medium actually displaced by the perforated microstructures), comprises at least 70% of the volume of the average particle (or less than 70). % of the virtual particle). More preferably, the volume of the microparticulate matrix comprises less than about 50%, 40%, 30% or even less than 20% of the volume of the average particle. Even more preferably, the average volume of the layer / matrix comprises less than about 10%, 5% or 3% of the volume of the average particle. Those skilled in the art will appreciate that typically such matrix or layer volumes contribute somewhat to the density of the virtual particle that is dictated overwhelmingly by the suspension medium discovered in the present invention. Of course, in the selected embodiments, the excipients or bioactive agents used to form the perforated microstructure can be chosen, so that the density of the resulting matrix or layers, approximates the density of the surrounding suspension medium. It will be appreciated that, the use of said microstructures will allow the apparent density of the virtual particles to approach that of the suspension medium. Furthermore, as previously indicated, the components of the microparticulate matrix are preferably selected, taking into account as far as possible other considerations, to approximate the density of the suspension medium. Therefore, in the preferred embodiments of the present invention, the virtual particles and the suspension medium will have a differential density less than about 0.6 g / cm 3. That is, the average density of the virtual particles (as defined by the boundary of the matrix) will be within approximately 0.6 g / cm3 of the suspension medium. More preferably, the average density of the virtual particles will be within 0.5, 0.4, 0.3 or 0.2 g / cm3 of the selected suspension medium. Even in more preferred embodiments, the density differential will be less than about 0.1, 0.05, 0.01, or even less than 0.005 g / cm3. In addition to the aforementioned advantages, the use of hollow, porous particles allows the formation of free-flowing dispersions comprising fractions of larger volume particles in the suspension. It should be appreciated that, the formulation of prior art dispersions in volume fractions approaching close packing results in dramatic increases in the viscoelastic behavior of the dispersion. The rheological behavior of this type is not appropriate for inhalation applications. Those skilled in the art will appreciate that, the volume fraction of the particles, can be defined as the ratio of the apparent volume of the particles (e.g., the volume of the particle) to the total volume of the system. Each system has a maximum volume fraction or package fraction. For example, the particles in the simple cubic distribution reach a maximum packing fraction of 0.52, while those in a closed cubic / hexagonal centered packing configuration reach a maximum packing fraction of about 0.74. The derived values are different for non-spherical particles or polydispersion systems. Therefore, the maximum packaging fraction is often considered as an empirical parameter for a given system. In the present invention it was surprisingly discovered that the use of porous structures in the present invention did not introduce undesirable viscoelastic behavior even in high volume fractions approaching the package. On the contrary, said microstructures remain as free-flowing low viscous suspensions, which have little or no stress when compared to analogous suspensions comprising solid particulates. It is thought that the low viscosity of the described preferred suspensions is due, at least in large part, to the relatively low van der Waals attractive force between the porous, hollow, liquid filled particles. Therefore, in the selected embodiments, the volume fraction of the dispersions described is greater than about 0.3. Other modalities may have packing values in the order of 0.3 to 0.5, or in the order of 0.5 to 0.8, with the highest values approaching a closed package condition. In addition, since the sedimentation of the particle tends to decrease naturally when the volume fraction approaches the closed package, the formation of relatively concentrated dispersions can further increase the stability of the formulation. Although the methods and compositions of the present invention can be used to form relatively concentrated suspensions, the stabilization factors work equally well in smaller package volumes and, said dispersions are contemplated to be within the scope of the present disclosure. With respect to this, it will be appreciated that dispersions comprising low volume fractions, are extremely difficult to stabilize, using prior art techniques. Conversely, dispersions incorporating micructures comprising a bioactive agent such as that described in the present invention are particularly stable even in low volume fractions. Therefore, the present invention allows the stabilized dispersions and particularly, the respiratory dispersions that will be formed and used in fractions of volume less than 0.3. In some preferred embodiments, the volume fraction is from about 0.0001-0.3, or more preferably from 0.001-0.01. Still other preferred embodiments comprise stabilized suspensions having volume fractions from about 0.01 to about 0.1. In other preferred embodiments, the perforated micructures can be used to stabilize dilute suspensions or micronized bioactive agents. In such embodiments the perforated micructures can be added to the volume fraction of the particles in the suspension, thereby increasing the stability of the suspension with respect to cremation or sedimentation. Additionally in these modalities, the incorporated micructures can also act to avoid the close approximation (aggregation) of micronized drug particles. It should be noted that the perforated micructures incorporated in said modalities do not necessarily comprise a bioactive agent. Rather, they may be formed exclusively from various excipients including surfactants. Of course, it will also be appreciated that the stabilized dispersions of the present invention may comprise relatively solid or non-perforated particulates, without the addition of perforated micructures. That is, depending on the size, composition and density of the suspended microparticulates, as well as the selection of the suspension medium, the effective particulate dispersions for nebulization can be formed using relatively non-porous or micronized particulates. In a preferred embodiment, the suspended particulates may comprise nanocrystals such as those described in U.S. Patent No. 5,667,809 which is incorporated herein by reference. As in the embodiments comprising perforated micructures, said preparations preferably comprise a fluorochemical suspension medium. Therefore, in a broad sense, the present invention provides the formation and pulmonary administration of stabilized dispersions comprising relatively non-porous particulates (e.g. micronized particles), porous particulates (e.g., porous, hollow, or perforated micructured microspheres) and combinations from the same. Although the stabilized dispersions may comprise particulates exhibiting various morphologies, the particularly preferred embodiments of the present invention comprise a plurality of perforated micructures or microparticles that are dispersed or suspended in the suspension medium. In such embodiments, the perforated micructures comprise a structural matrix that exhibits, defines or comprises voids, pores, defects, voids, spaces, interstisial spaces, openings, perforations and holes that allow the surrounding suspension medium to penetrate, fill or soak freely the micructure. The absolute shape (opposite to the morphology) of the perforated micructure is generally not critical and, any general configuration that provides the desired stabilization characteristics, is contemplated to be within the scope of the present invention. Therefore, although preferred embodiments incorporate perforated micructures, they may comprise approximately microspherical, collapsed, deformed or fractured particulates, they are also compatible. With this observation, it will be appreciated that the particularly preferred embodiments of the present invention comprise spray dried, hollow and porous microspheres. In order to maximize the stability of the dispersion and optimize the distribution in the administration, the average geometric particle size of the perforated microstructures is preferably approximately 05.50 m, more preferably 1.30 m. It will be appreciated that large particles (e.g. greater than 50 m) should not be used as large particles that may tend to aggregate or separate from the suspension and not be effectively nebulized. In the especially preferred embodiments, the average geometric size of the particle (or diameter) of the perforated microstructures is less than 20 m or less than 10 m. More preferably, the average geometric diameter is less than 5 m. In especially preferred embodiments, the perforated microstructures will comprise a powder of dry, hollow, porous microspherical layers of approximately 1 to 10 m in diameter, with a layer thickness of from about 0.1 m to about 0.5 m. It is a particular advantage of the present invention that the particulate concentration of the components of the dispersions and of the structural matrix can be adjusted to optimize the delivery characteristics of the selected particle size. As indicated by the above specification, the dispersions of the present invention are preferably stabilized. In a broad sense, the term "stabilized dispersion" will be maintained, as the meaning of any dispersion that resists aggregation, flocculation or cremation to the extent required to provide effective administration of a biochemical agent. Although those skilled in the art will appreciate that there are some methods that can be used to evaluate the stability of a given dispersion, a preferred method for the purposes of the present invention comprises determining the time of cremation or settling. With regard to this, the time of cremation should be defined as the time in which the suspended drug particulates, skim up to 1 / z, the volume of the suspension medium. Similarly, the sedimentation time can be defined as the time it takes for the particulates to settle within Vz, the volume of the liquid medium. A relatively simple way to determine the time of cremation of a preparation is to provide the particulate suspension in a sealed glass jar. The bottles are agitated or moved to provide relatively homogeneous dispersions which are subsequently placed apart and observed, using the appropriate instruments or by visual inspection. Subsequently, the necessary time is observed for the suspended particulates to disintegrate up to Vz the volume of the suspension medium (for example, to rise to the upper half of the suspension medium), or to settle within the! of the volume (for example, they settle in V of the middle of the middle). Suspension formulations having a cremation time greater than 1 minute e are preferred, indicating adequate stability. More preferably, the stabilized dispersions comprise cremation times greater than about 2, 5, 10, 15, 20 or 30 minutes. In the particularly preferred embodiments, the stabilized dispersions exhibit cremation times greater than about 1, 15, 2, 2.5, 3, 4 or even 5 hours. Substantially equivalent periods for settling times are indicative of compatible dispersions. With respect to the preparations of the present invention, the porosity of the incorporated microstructures can contribute significantly to establishing the stability of the dispersion. With respect to this, the average porosity of the perforated microstructures can be determined through an electron microscope coupled with modern imaging techniques. More specifically, the electron micrographs of the representative samples of the perforated microstructures can be obtained and digitally analyzed to quantify the porosity of the preparation. Said methodology is well known in the art and can be committed without undue experimentation. For the purposes of the present invention, the average porosity (e.g. the percentage of the surface area of the particle that is open in the interior and / or a central void) of the perforated microstructures may be in the range of from about 0.5% up to approximately 80%. In the most preferred embodiments, the average porosity will be within the range of from about 2% to about 40%. Based on the selected production parameters, the average porosity can be greater than approximately 2%, 5%, 10%, 15%, 20%, 25% or 30% of the surface area of the microstructure. In other embodiments, the average porosity of the microstructures may be greater than about 40%, 50%, 60%, 70% or even 80%. As regards the pores, they are usually within the size range of from about 5 nm to about 400 nm, with average pore sizes preferably within the range of from about 20 nm to about 200 nm In the particularly preferred embodiments, the average pore size will be within the range of from about 50 nm to about 100 nm. As can be seen in the Figures from 1A1 to 1F2 and as will be discussed in more detail below, it is a significant advantage of the present invention that the pore size and porosity can be closely controlled by the careful selection of the built-in components and the production parameters. Along with the geometrical configuration, the design of perforated or porous and / or hollow microstructures can also play an important role in the properties of the resulting aerosol during nebulization. In this regard, the perforated structure and relatively high surface area of the dispersed microparticles make it possible to transport them along the aerosol cloud during inhalation more easily and over longer distances than non-perforated particles. of comparable size. Due to its high porosity, the density of the particles is significantly less than 1.0 g / cm3, normally less than 0.5 g / cm3, more often of the order of 0.1 g / cm3 and, as low as 0.01 g / cm3. Unlike the geometric size of the particle, the aerodynamic size of the particle, d aer of the perforated microstructures depends substantially on the density of the particle, p: d aer = d geop, where d is the geometrical diameter. For a particle density of 0.1 g / cm3, d aer will be rigorously three times smaller than d geo, leading to an increased particle deposit in the peripheral regions of the lung and a correspondingly smaller deposit in the throat. In this respect, the average aerodynamic diameter of the perforated microstructures is preferably less than about 5 μm, more preferably less than about 3 μm, and in particularly preferred embodiments less than about 2 μm. Said particle distributions will act to increase the depth of deposit in the lung of the agent administered. As will be shown subsequently in the Examples, the particle size distribution of the aerosol formulations of the present invention are measurable by conventional techniques such as cascade impaction or, through analytical methods of time of flight. The determination of the dose emitted in the nebulized inhalations was carried out according to the Pharmacopeia U.S. proposed (Pharmacopeial Previews, 22 (1996) 3065), which is incorporated in the present invention as a reference. These and related techniques, make it possible for them to be calculated, the "final particle fraction" of the nebulized aerosol, which corresponds to said particulates that are likely to be deposited in the lung effectively. As used in the present invention, the phrase "fine particle fraction" refers to the percentage of the total amount of active drug, administered by actuation from the nozzle on plates 2-7 of an Andersen cascade filter. Step 8. Based on said measures, the formulations of the present invention will preferably have a fine particle fraction for administration by local air, of approximately 20% or more by weight of the perforated microstructures (w / w). More preferably, they will exhibit a fine particle fraction of from about 25% to 80% w / w, and even more preferably from about 30 to 70% w / w. In the selected embodiments of the present invention, a fine particle fraction greater than about 30%, 40%, 50%, 60%, 70% or 80% by weight will be understood. For systemic administration, the fine particle fraction will be greater preferably at 80% by weight, more preferably, greater than 90% by weight. Any configuration and / or size distribution is finally selected for the incorporated particulate (either a perforated microstructure or a relatively solid non-porous particulate), the composition thereof can comprise any of the numbers of compatible materials. With respect to the perforated microstructures, it will be appreciated that, as used in the present description, the terms "structural matrix" or "microstructure matrix" are equivalent and must be held as meaning any solid material that forms the perforated microstructures. , which define a plurality of voids, openings, voids, defects, pores, holes, cracks, etc., that promote the formation of stabilized dispersions, as explained above. The structural matrix can be soluble or insoluble in an aqueous environment. In the preferred embodiments, the perforated microstructure defined by the structural matrix comprises a hollow porous, dry dew microsphere, which incorporates at least one surfactant. For the other selected modalities, the particulate material may be covered one or more times with polymers, surfactants or other compounds, which help the suspension. More generally, the particulates useful in the stabilized dispersions of the present invention can be formed of any biocompatible material that is relatively stable and preferably insoluble with respect to the selected suspension medium. Although a wide variety of materials can be used to form the particles, in the particularly preferred embodiments, the particles (or structural matrix) is associated with, or comprises, a surfactant such as a phospholipid or fluorinated surfactant. Although the incorporation of a compatible surfactant is not required, this can improve the stability of respiratory dispersions, increase lung deposition and facilitate preparation of the suspension. In addition, by altering the components, the density of the particle or structural matrix can be adjusted to approximate the density of the surrounding medium and stabilize the dispersion further. Finally, as will be described in more detail below, the perforated microstructures preferably comprise at least one bioactive agent. As stated above, the relatively non-porous particles or perforated microstructures of the present invention may optionally be associated with, or comprise, one or more surfactants. In addition, the miscible surfactants can optionally be combined with the liquid phase of the suspension medium. It will be appreciated by those skilled in the art, that the use of surfactants, although not necessary to practice the present invention, they may further increase the stability of the dispersion, simplify the formulation processes or increase the bioavailability in the administration. Of course combinations of surfactants, including the use of one or more in the liquid phase and, one or more associated with the perforated microstructures, are contemplated to be within the scope of the present invention. By "associated with or comprising" it is understood that the perforated particle or microstructure can incorporate, adsorb, absorb, be covered with or be formed by the surfactant. In a broad sense, surfactants suitable for use in the present invention include any compound or composition that helps in the formation and maintenance of stabilized respiratory dispersions, forming a layer at the interface between the particle and the suspension medium. The surfactant may comprise a simple compound or any combination of the compounds, such as in the case of co-surfactants. Particularly preferred surfactants are substantially insoluble in the medium, non-fluorinated and selected from the group consisting of saturated and unsaturated lipids, non-ionic detergents, non-ionic block copolymers, ionic surfactants and combinations of said agents. It should be emphasized that, in addition to the aforementioned surfactants, suitable surfactants (eg, biocompatible) are compatible with the teachings of the present invention and can be used to provide the desired stabilized preparations.

The lipids, including phospholipids, from both natural and synthetic sources are particularly compatible with the present invention and can be used in the variation of concentrations to form the particle or structural matrix. Generally compatible lipids comprise those which have a gel for a transition of the liquid crystal phase greater than about 40 ° C. Preferably, the incorporated lipids are relatively long chain saturated lipids (for example C18-C22) and, preferably, comprise phospholipids. Phospholipids Exemplary useful in the stabilized preparations disclosed comprise egg phosphatidylcholine, dilauroylphosphatidylcholine, dioleylphosphatidylcholine, dipalmitoilfosfatidel choline, disteroilfosfatidelcolina, fosfatideilcolinas short chain, phosphatidylethanolamine, dioleylphosphatidylethanolamine, phosphatidylserine, phosphatidylglycerol, phosphatidylinositol, glycolipids, ganglioside GM1, esfingomielin, phosphatidic acid, cardiolipin; polymer chains containing lipids, such as polyethylene glycol, chitin, hyaluronic acid or polyvinylpyrrolidene; mono-di sulphonates containing lipids and polysaccharides; fatty acids, such as palmitic acid, stearic acid and oleic acid; cholesterol, cholesterol esters and cholesterol hemisuccinate. Due to their excellent biocompatibility characteristics, phospholipids and combinations of phospholipids and poloxamers are particularly suitable for use in the stabilized dispersions described in the present invention.

Compatible nonionic detergents comprise: sorbitan esters including sorbitan trioleate (Span® 85), sorbitan sesquioleate, sorbitan monooleate, sorbitan monolaurate, polyoxyethylene sorbitan monolaurate (20) and polyoxyethylene sorbitan monooleate (20), ether polyoxyethylene oleyl (2), polyoxyethylene esters (2), polyoxyethylene lauryl ether (4), glycerol esters, and sucrose esters. Other suitable non-ionic detergents can be readily identified, using McCutcheon Emulsifiers and Detergents (CmPublishing Col, Glen Rock, New Jersey), which are incorporated in their entirety in the present invention. Preferred block copolymers comprise diblock and triblock copolymers of polyoxyethylene and polyoxypropylene, including polaxamer 188 (Pluronic "F-68), poloxamer 407 (Pluronic" F-127), and ploxamer 338. Ionic surfactants such as Sodium sulfosuccinate and fatty acid soaps. In the preferred embodiments, the microstructures may comprise oleic acid or its alkali salt. In addition to the aforementioned surfactants, cationic surfactants or lipids are especially preferred in the case of administration of RNA or DNA. Examples of cationic lipids include: cetylpyridinium chloride, DOTMA, N- [1- (2-3-dioleyloxypropyl) chloride -N, N, N -trimethyl ammonium, DOTAP, 1,2-dioleyloxy-3- (trimethylammonium) propane, and DOTB, 1-2-dioleyl-3- (4'-trimethylammonium) butanoyl-sn-glycerol. Polycationic amino acids such as polylysine and polyarginine are contemplated, Those skilled in the art will further understand that a wide range of surfactants, including those described above, may optionally be used in conjunction with the present invention. It can be easily determined for a given application, through empirical studies that do not require undue experimentation, and it will be further appreciated that the preferred insolubility of any The surfactant incorporated in the suspension medium will dramatically decrease the activity of the associated surface. Therefore, it is debatable whether these materials have surfactants as a priority, to contract an aqueous bioactive surface (for example, aqueous hypophase in the lung). Finally, as will be described in more detail below, the surfactants comprising the porous particles, may also be useful in the formation of oil-in-water precursor emulsions (eg, spray drying the feed pile) used during processing to form the bioactive structural or particulate matrix. Unlike the prior art formulations, it has been surprisingly discovered that the incorporation of relatively high levels of surfactants (for example phospholipids) can be used to increase the stability of the described dispersions. That is, in a weighing process for the weight bases, the structural matrix of the perforated microstructures may comprise relatively high levels of surfactant. In this regard, the perforated microstructures will preferably comprise more than about 1%, 5%, 10%, 15%, 18% or even 20% w / w of surfactant. More preferably, the perforated microstructures will comprise more than about 25%, 30%, 35%, 40%, 45% or 50% w / w of surfactant. Still other exemplary embodiments will comprise perforated microstructures wherein the surfactant or surfactants are present in a percentage greater than about 55%, 60%, 70%, 75%, 80%, 85%, 90% or even 95% w / w . In the selected embodiments, the perforated microstructures will comprise essentially 100% w / w of a surfactant, such as a phospholipid. Those skilled in the art will appreciate that, in such cases, the balance of the structural matrix (where applicable), will likely comprise a bioactive agent (s) or excipient (s) of non-active surface or additive (s). As previously indicated, stabilized dispersions comprising perforated microstructures simply represent a preferred embodiment of the present invention. Therefore, although such levels of surfactants are preferably employed in perforated microstructures, equivalent surfactant levels can also be used to provide systems comprising relatively non-porous or substantially solid particulates. That is, although preferred embodiments will comprise perforated microstructures or microspheres associated with high levels of surfactant, acceptable dispersions can be formed using relatively low or non-porous particulates (eg, micronized particulates) of the same surfactant concentration. With respect to this, said embodiments are specifically contemplated to be within the scope of the present invention. In other preferred embodiments, the relatively non-porous particles or structural matrix that defines the perforated microstructures, optionally comprise synthetic or natural polymers or combinations thereof. In this regard, useful polymers include polylactides, polylactide glycides, cyclodextrins, polyacrylates, methylcellulose, carboxymethylcellulose, polyvinyl alcohols, polyanidrides, polylactones, polyvinyl pyrrolidones, polysaccharides (dextrans, starches, chitin, chitosan, etc.) hyaluronic acid , proteins, (albumin, collagen, gelatin, etc).

Those skilled in the art will note that, by selecting the appropriate polymers, the administration profile of the respiratory dispersions can be tailored to optimize the effectiveness of the bioactive agent. In addition to the aforementioned polymeric and surfactant materials, it may be desirable to add other excipients to the inhalation formulation, to improve the rigidity of the microsphere (or non-porous particulate), the deposition and administration of the drug, the shelf life and the patient acceptance. Such optional excipients include but are not limited to: coloring agents, taste-inhibiting agents, buffers, hygroscopic agents, antioxidants and chemical stabilizers. Additionally, the excipients may be incorporated into or added to the particles or particulate matrix to provide structure and shape for the perforated microstructures (e.g., microspheres). Such excipients may include, but are not limited to, carbohydrates include monosaccharides, disaccharides and polysaccharides. For example, monosaccharides such as dextrose (anhydride and monohydrate), galactose, amnitol, D-mannose, sorbitol, sobose and the like; disaccharides such as, lactose, maltose, sucrose, treaiosa, and the like; trisaccharides such as raffinose and the like; and other carbohydrates such as starches (hydroxyethyl starch), cyclodextrins and maltodextrins. Amino acids are also suitable excipients with preferred glycine. Mixtures of carbohydrates and amino acids are further maintained to be within the scope of the present invention. Also contemplated is the inclusion of both inorganic (eg, sodium chloride, calcium chloride) and organic salts (eg, sodium citrate, sodium ascorbate, magnesium gluconate, sodium gluconate hydrochloride tromethamine) and buffers. Of course, it will be appreciated that, the selected excipients may be added to the dispersion as separate particles or perforated microstructures. Still other preferred embodiments include non-porous particles or perforated microstructures which may comprise, or may be covered with, charged species that prolong the residence time at the point of contact or improve penetration through the mucosa. For example, anionic charges are known to favor mucoadhesion, while cationic charges can be used to associate the microparticulate formed with negatively charged bioactive agents, such as genetic material. The fillers can be imparted through the association or incorporation of polyanionic or polycationic materials such as polyacrylic acids, polylysine, polylactic acid and chitosan. In addition to, or instead of, the aforementioned components, the particles, perforated microstructures or aqueous emulsion droplets, will preferably comprise at least one bioactive agent. As used in the present description, "bioactive agent" refers to a substance which is used in connection with an application that is therapeutic or diagnostic in nature, such as in methods for diagnosing the presence or absence of a disease in a patient and / or methods for the treatment of a disease in a patient. Particularly preferred embodiments for use in accordance with the present invention include anti-allegorics, peptides and proteins, bronchodilators and anti-inflammatory steroids for use, by means of inhalation therapy, in the treatment of respiratory disorders such as asthma.

It will be appreciated that the distributed particles or perforated microstructures of the present invention may comprise one or more bioactive agents (e.g. 100% w / w). However, in the selected modalities, perforated particles or microstructures can incorporate much less bioactive agent, depending on the activity thereof. Thus, for highly active materials, the particles can incorporate as little as 0.001% by weight, although a concentration greater than about 0.1% is preferred. Other embodiments of the present invention may comprise more than about 5%, 10%, 15%, 20%, 25%, 30% or even 40% w / w of bioactive agent. Even more preferably, the perforated particles or microstructures may comprise more than about 50%, 60%, 70%, 75%, 80% or even 90% w / w of bioactive agent. In particularly preferred embodiments, the desirable stabilized respiratory dispersion contains from about 40% -60% w / w, more preferably 50-70% w / w, and even more preferably 60% -90% w / w agent bioactive, relative to the weight of the microparticulate or particulate matrix. The precise amount of bioactive agent incorporated in the stabilized dispersions of the present invention depends on the agent of choice, the dose required and the form of the drug currently used for incorporation. Those skilled in the art will appreciate that such determinations can be made using well known pharmacological techniques, in combination with the teachings of the present invention. Therefore, bioactive agents that can be administered in the form of aerosolized medicaments in conjunction with the teachings of the present invention, include any drug that is presented in a form that is subjected to pulmonary cannon in physiologically effective amounts. In the selected embodiments (e.g., particulate dispersions), the incorporated agent will preferably be relatively insoluble in the suspension medium. In other embodiments, such as inverse emulsions, the selected agent may be substantially soluble in the dispersion phase. Preferred preferred embodiments comprising an inverse emulsion will preferably comprise a hydrophilic bioactive agent. In any case, compatible bioactive agents may comprise hydrophilic and lipophilic respiratory agents, bronchodilators, antibiotics, antivirals, anti-inflammatories, spheroids, antihistamines, histamine antagonists, inhibitors or antagonists of leukotriene, anticholinergics, antineoplastic agents, anesthetics, enzymes, surfactants of lung, cardiovascular agents, mataerialgenetic including, DNA and RNA, viral vectors, immunoactive agents, imaging agents, vaccines, immunosuppressive agents, peptides, proteins and combinations thereof. Particularly preferred bioactive agents for local administration using aerosolized medicaments according to the present invention include mast (anti-allelicic) cell inhibitors, bronchodilators and anti-inflammatory steroids, for use, through inhalation therapy, in the treatment of disorders respiratory drugs such as asthma, for example cromolyn (for example sodium salt), and albuterol (for example, the sulfate salt). For systemic administration (for example for the treatment of autoimmune diseases such as diabaetes or multiple sclerosis), peptides and proteins are particularly preferred.

Exemplary drugs of bioactive agents can be selected from, for example, analgesic, for example codeine, dihromyromione, ergotamine, fentanyl or morphine; anginal preparations, for example, diltiazema, mast cell inhibitors, for example cromolyn sodium; antiinfectants, for example cephalosporins, macrolides, quinolines, penicillins, streptomycin, sulfonamines, tetracyclines and pentamildines; antihistamines, for example metapyrylene; anti-inflammatories, for example, fluticasone propionate, beclomethasone dipropionate, flunisolide, budesonide, tripedane, cortisone, prednisone, prednisilone, dexamethasone, betametsone or triamcinolone acetonide, antitussives, for example, noscapine; bronchodilators, for example ephedrine, adenaline, fenoterol, formoterol, isoprenaline, metaproterenol, salbutamol, albuterol, salmeterol, terbutaline; diuretics, for example, amiloride, anticholinergics, for example iaptropium, atropine, or oxitropium; lung surfactants, for example Surfaxin, Exosurf, Survanta; xanthines, for example aminophylline, theophylline, caffeine, therapeutic proteins and peptides, for example DNase, insulin, glocagon, T-cell receptor agonists or antagonists, LHRH, nafarelin, goserelin.leuprolide, interferon, rhu IL-1 receptor, macrophage activation, such as limfonkins and muramyl dipeptides, opioid peptides and neuropéptidos such as, encafalinas, endorfinas, renin inhibitors, colecciostoquinias, hormones of growth, inhibitors of leucotrieno, a-antitripsin, and similars. In addition, bioactive agents comprising an RNA or DNA sequence, particularly those useful for gene therapy, genetic vaccination or tolerization or anti-perception applications, can be incorporated into the described dispersions, as indicated in the present invention. Representative DNA plasmas include pCMVβ (available from Genzime Corp. Framington, MA) and pCMVß-gal (a CMV promoter linked to the E. xoli Lac-Z gene, which encodes the above β-galactosidase). With respect to particulate dispersions, the selected bioactive agent (s) may be associated with, or incorporated into, the perforated particles or microstructures in any form that provides the desired efficacy and is compatible with the selected production techniques. Similarly, the bioactive agent may be associated with the discontinuous phase of an inverse emulsion. As used in the present invention, the terms "associated" or "associating" mean that the structural matrix, perforated microstructure, relatively non-porous particle or discontinuous phase, may comprise, incorporate, adsorb, absorb, be covered with or be formed by the bioactive agent. Where appropriate, the medicaments can be used in the form of salts (for example, alkali metal or amino salts or as acid addition salts), or as esters, or as solvates (hydrates). With respect to this, the form of the bioactive agents can be selected to optimize the activity and / or stability of the drug and / or, to minimize the solubility of the drug in the suspension medium. It will be further appreciated that, aerosolized formulations according to the present invention, may, if desired, contain a combination of two or more active ingredients. The ingredients may be provided in combination with a simple species of perforated microstructure or particle or, individually in separate species that are combined in the suspension medium or continuous phase. For example, two or more bioactive agents can be incorporated into a single feed and dry spray cell preparation, to provide a kind of simple microstructure comprising a plurality of drugs. Conversely, individual drugs could be added to separate piles and dry mist separately to provide a plurality of microstructure species with different compositions. These individual species, they could be added to the medium in any desired proportion and placed in administration systems by inhalation, as described below. Additionally, as already briefly mentioned, perforated microstructures (with or without an associated medicament) can be combined with one or more conventionally micronized bioactive agents to provide the desired dispersion stability. Based on the foregoing, it will be appreciated by those skilled in the art that a wide variety of bioactive agents may be incorporated in the stabilized dispersions described. Therefore, the above list of preferred bioactive agents is by way of example only and is not intended to be limiting. It will also be appreciated by those skilled in the art that the appropriate amount of bioactive agent and dosing schedule may be determined by the formulations according to the existing information and without undue experimentation. As noted in the above conduits, various components associated with, or incorporated in the discontinuous phase, perforated microstructures or particles of the present invention can be used. Similarly, similar techniques can be used to provide particulates having compatible physiochemical properties, morphology (eg, perforated configuration) and density. Among other methods, perforated microstructures or particles compatible with the present invention can be formed by techniques including lyophilization, spray drying, multiple emulsion, micronization or crystallization. In preferred embodiments, relatively non-porous particles can be produced using techniques such as micronization, crystallization or grinding. It will be further appreciated that, the basic concepts of many of these techniques are well known in the prior art and, in view of the techniques described herein, do not require undue experimentation to adapt them to provide the desired particulates. Although some methods are generally compatible with the present invention, the particularly preferred embodiments usually comprise perforated particulates or microstructures formed by spray drying. As is well known, spray drying is a one-phase process that converts a liquid feed into a dry particulate form. With respect to pharmaceutical applications, it will be appreciated that spray drying has been used to provide powder material for various routes of administration, including inhalation. Observe, for example, M Sacchetti and M.M. Van Oort in: Inhalation Aerosols: Physical and Biological Basis for Therapy, A.J. Hickey, ed. Marcel Dekkar, New York, 1996, which is incorporated in the present invention as a reference. In general, spray drying consists of providing a highly dispersed liquid and a sufficient volume of hot air together to produce evaporation and drying of the liquid droplets. The preparation for spray drying or feeding (or feed pile), can be any solution, series suspension, slurry, colloidal dispersion or paste that can be atomized using the selected spray drying apparatus. Normally, the feed is sprayed in a stream of warm filtered air that evaporates the solvent and transports the dried product to a collector. Subsequently, the air used is expelled with the solvent. Those skilled in the art will appreciate that, various different types of apparatus can be used to provide the desired product. For example, commercial spray dryers manufactured by Buchi Ltd., or Niro Corp., will produce particles of the desired size effectively. It will be further appreciated that, these spray dryers, and specifically their atomizers, can be modified or used for specialized applications., for example, the simultaneous spray of two solutions using a double nozzle technique. More specifically, a water-in-oil emulsion can be atomized from a nozzle, and an anti-adherent-containing solution, such as mannitol, can be atomized together from a second nozzle. In other cases, it may be desirable to push the feed solution through a customarily designed nozzle, using a high pressure liquid chromatography (HPLC) pump. Provided that microstructures comprising the correct morphology and / or composition are produced, the choice of the apparatus is not critical and, in view of the teachings of the present invention, would be apparent to those skilled in the art.

Although normally the resulting spray-dried powder particles are approximately spherical in shape, of almost uniform size and are often hollow, there may be some degree of shape irregularity, depending on the incorporated medicament and the spray drying conditions. In many cases, the dispersion stability of air-dried microspheres or particles that appears to be most effective in an inflation agent (or blowing agent) is used in its production. Particularly preferred embodiments may comprise an emulsion with the inflation agent as the dispersing or continuous phase (the other phase being aqueous in nature). The inflation agent is preferably dispersed with a surfactant solution, using, for example, a commercially available microfluidizer at a pressure of from about 5,000 to 15,000 psi. This process forms an emulsion, preferably stabilized by a built-in surfactant, which normally comprises an inmixable blowing agent of submicron water droplets, dispersed in a continuous aqueous phase. The formation of such dispersions using this and other techniques are common and well known to those skilled in the art. The blowing agent is preferably a fluorinated compound (for example, perfluorohexane, perfluorooctyl bromide, perfluorodecalin, perfluorobutyl ethane), which vaporizes during the spray drying process, generally leaving the hollow, aerodynamically light and porous microspheres behind. As will be described in more detail below, other suitable blowing agents include chloroform, Freons and hydrocarbons. Nitrogen gas and carbon dioxide are also contemplated as suitable blowing agents. Although the perforated microstructures are formed preferably using a blowing agent as described above, it will be appreciated that, in some cases, the blowing agent is not required to be added and an aqueous dispersion of the medicament is spray dried directly. surfactant (s). In such cases, the formulation may be sensitive to process conditions (e.g., elevated temperatures) which generally lead to the formation of relatively porous hollow microparticles. In addition, the medicament may possess special physiochemical properties (eg, high crystallinity, high melting temperature, surface activity, etc.), which make it particularly suitable for use in such techniques. When a blowing agent is employed, the degree of porosity of the perforated microstructure appears to depend, at least in part, on the nature of the blowing agent, its concentration in the feed pile (eg, an emulsion) and, the conditions of spray drying. With respect to porosity control, it has been surprisingly discovered that the use of compounds, hitherto unappreciated as blowing agents, can provide particulates or perforated microstructures having particularly desirable characteristics. More particularly, in this new and unexpected aspect of the present invention, it has been discovered that the use of fluorinated compounds having relatively high boiling points (eg, greater than about 60 ° C), can be used to produce particulates that are especially suitable for inhalation therapies. In this regard, it is possible to use fluorinated blowing agents having boiling points greater than about 70 ° C, 80 ° C, 90 ° C or even 95 ° C. Particularly preferred blowing agents have boiling points greater than the boiling point of water, for example greater than 100 ° C (for example perflubron, perfluorodecalin). In addition, blowing agents with relatively low water solubility (<10 ° M) are preferred, since they make it possible to produce stable emulsion dispersions with average diameters of heavy particles less than 0.3 μm. As indicated aboveThese blowing agents will preferably be incorporated in an emulsified feed cell before being spray dried. For the purposes of the present invention, this feeding cell will preferably comprise one or more bioactive agents, one or more surfactants, one or more excipients. Of course, the combinations of the aforementioned components are also within the scope of the present invention. Although the present invention is by no means limited, it is hypothesized that, since the aqueous feed component evaporates during spray drying, it leaves a thin crust on the surface of the particle. The resulting wall or scale of the particle, formed during the initial moments of spray drying, seems to trap any high-boiling blowing agent, such as hundreds of drops of the emulsion (ca. 200-300 nm). As the continuous drying process, the internal pressure of the particulate increases, so that at least part of the incorporated blowing agent evaporates and is forced through the relatively thin crust. Apparently, this ventilation or exit of gases, leads to the formation of pores or other defects in the crust. At the same time, the particulate components remain (possibly including some blowing agent) migrating from the inside to the surface, in the form of solidifiers of the particle. This migration is apparently slow during the drying process, as a result of the increased resistance to group the transfer caused by an increased internal viscosity. Once the migration ceases, the solidifiers of the particle leave vesicles, vacuums or voids where the emulsifying agent resided. The number of pores, their size and the resulting thickness of the wall, depend in large part on the nature of the selected blowing agent (for example, boiling point), its concentration in the emulsion, the total concentration of solids and of the conditions of spray drying.

It has been surprisingly discovered that the substantial amounts of these relatively high boiling blowing agents can be retained in the resultant spray-drying product. That is, the spray-dried perforated microstructures can comprise as much as 5%, 10%, 20%, 30% or even 40% w / w of blowing agent. In such cases, higher outputs were obtained as a result of an increased density of the particle, caused by the residual blowing agent. Those skilled in the art will appreciate that this retained fluorinated blowing agent can alter the surface characteristics of the perforated microstructures and further increases the stability of the respiratory dispersions. Conversely, the residual blowing agent can be easily removed with a post-production evaporation phase in a vacuum oven. The pores can optionally be formed by spray drying a bioactive agent and an excipient that can be removed from the microspheres formed under vacuum. In such a case, typical concentrations of blowing agent in the feed stack are within 5% and 100% w / v, and more preferably, between about 20% to 90% w / v. In other embodiments, the concentrations of the blowing agent will preferably be greater than about 10%, 20%, 30%, 40%, 50% or even 60% w / v. Still other feed cell emulsions may comprise 70%, 80%, 90% or even 95% w / v of the selected high boiling compound. In the preferred embodiments, another method of identifying the concentration of the blowing agent used in the feed is to provide it as a ratio of the concentration of the blowing agent to said stabilizing surfactant (eg, phospholipid) in the precursor emulsion). For fluorocarbon blowing agents, such as perfluorooctyl bromide and phosphatidylcholine, the ratio can be determined by a perfluorocarbon / phosphatidylcholine ratio (or PFC / PC ratio). Of course, it will be appreciated that other compatible surfactants can also be used to provide compatible particulates. In any case, the PFC / PC ratio will normally be in the range of from about 1 to about 60, and more preferably from about 10 to about 50. For the preferred embodiments, the ratio will generally be greater than about 5, 10, 20. , 25, 30, 40 or even 50. With respect to this, Figure 1 shows a series of drawings taken from perforated microstructures formed of phosphatidylcholine (PC), using various amounts of perfluorooctyl bromide (PFC) and a fluorocarbon knitted relatively high boiling as the blowing agent. The proportions PFC / PC, are provided under each subgroup of drawings, for example, from 1A to 1 F. The conditions of training and image, are discussed in more detail in Examples I and II found below. With respect to the micrographs, the column on the left shows the intact microstructures, while the column on the right illustrates cross sections of fractured microstructures from the same preparations. As can be seen more easily in Figure 1, the use of PFC / PC ratios provides more hollow and porous structures. More particularly, methods employing a PFC / PC ratio greater than about 4.8 tend to provide structures that are particularly compatible with the dispersions described herein. Similarly, in Figure 2, a micrograph that will be discussed in more detail in Example II below, illustrates a preferably porous morphology, obtained using higher boiling point blowing agents (in this case perfluorodecalin) . Although relatively high boiling blowing agents comprise a preferred aspect in the present invention, it will be appreciated that more conventional blowing or inflation agents are also used to provide compatible perforated microstructures. Generally, the inflation agent can be any material that changes to gas at some point, during spray drying or post-production process. Suitable agents include: 1. dissolved low boiling solvents (below 100 ° C), with limited mixability with aqueous solutions, such as methylene chloride, acetone and carbon disulfide, used to saturate the solution at room temperature. 2. A gas, for example CO2 or N2, used to saturate the solution at room temperature and high pressure (for example 3 bar). Subsequently, the drops are supersaturated with the gas in 1 atmosphere and 100 ° C. 3. Emulsions of low boiling liquids (below 100 ° C), such as Freon 113, perfluoropentane, perfluorohexane, perfluorobutane, pentane, butane, FC-11, FC-11 B1, FC-11 B2, FC-12B2, FC-21, FC-21 B1, FC-21 B2, FC-31 B1, FC-113A, FC-112, FC-123, FC-132, FC-133, FC-141, FC-141 B, FC- 142, FC-151, FC-152, FC-1112, FC-1121 and FC-1131.

With respect to these lower boiling point inflation agents, they are usually added to the feed pile in amounts of from about 1% to 40% v / v of the surfactant solution. It has been found that the inflation agent of about 15% v / v produces a spray-dried powder, which can be used to form the stabilized dispersions of the present invention. Regardless of which blowing agent is finally selected, it has been found that perforated microstructures or compatible particles can be produced efficiently using a Büchi mini spray dryer (model B-191, Switzerland). As will be appreciated by those skilled in the art, the inlet temperature and outlet temperature of the spray dryer is not critical, but it will be of a level that provides the desired particle size and will result in a product having the desired activity. of the desired medication. In this regard, the inlet and outlet temperatures are adjusted depending on the melting characteristics of the components of the formulation and the composition of the feed stack. Therefore, the inlet temperature can be between 60 ° C and 170 ° C, with the outlet temperatures from about 40 ° C to 120 ° C, depending on the composition of the feed and the desired characteristics of the particulate . Preferably, these temperatures will be from 90 ° C to 120 ° C for the inlet and from 60 ° C to 90 ° C for the outlet. The flow range that will be used in the spray drying equipment will generally be from about 3 mi. per minute to approximately 5 mi. per minute. The air flow range of the atomizer can vary between the values of 1, 200 liters per hour to approximately 3,900 liters per hour. Commercially available spray dryers are well known to those skilled in the art, and suitable settings for any particular dispersion can be easily determined through the development of standard empirical tests with proper reference to the examples that follow . Of course, the conditions can be adjusted so that biological activity is conserved in the longer molecules, such as proteins or peptides. Particularly preferred embodiments of the present invention comprise spray-drying preparations comprising a surfactant such as a phospholipid and at least one bioactive agent. In other embodiments, the air-drying preparation may further comprise, an excipient comprising a hydrophilic portion such as, for example, a carbohydrate (e.g., glucose, lactose, or starch), in addition to any selected surfactant. In this regard, various starches and derivatized starches are suitable for use in the present invention. Other additional components may include modifiers, shock absorbers 9 conventional viscosities such as phosphate buffers or, other conventional biocompatible buffers or pH adjusting agents, such as acids or bases and, osmotic agents (to provide isotonicity, hyperosmolarity or hyposmolarity). Examples of such suitable salts include, sodium phosphate (both monobasic and dibasic), sodium chloride, calcium phosphate, calcium chloride and other physiologically acceptable salts. Any components that are selected, the first step in the production of particualdo, normally comprises the preparation of the power cell. Preferably, the selected drug is dissolved in water to produce a concentrated solution. The drug can also be dispersed directly in the emulsion, particularly in the case of water-insoluble agents. Alternatively, the drug can be incorporated in the form of a solid particulate dispersion. The concentration of the drug used depends on the dose of drug required in the final powder and on the performance or effectiveness of the nebulization device. You can add to this solution annex, as necessary, co-surfactants such as poloxamer 188 or span 80. Additionally, excipients such as sugars and starches may also be added. In the selected modalities, an oil-in-water emulsion is subsequently formed in a separate container. The oil employed is preferably a fluorocarbon (for example, perfluorooctyl bromide, perfluorodecalin), which is emulsified using a surfactant such as a saturated long chain phospholipid. For example, a gram of phospholipid can be homogenized in 150 gr. of hot distilled water (for example 60 ° C), using a suitable upper cut mechanical mixer (for example, Ultra-Turrax mixer model T-25) at 8000 rpm. for 2 to 5 minutes. Normally, while mixing, they are added in the form of drops of 5 to 25 gr. Fluorocarbon to the dispersed surfactant solution. Subsequently, the resulting perfluorocarbon emulsion in water is processed using a high pressure homogenizer to reduce the particle size. Normally, the emulsion is processed from 12,000 to 18,000 psi., 5 different passes and maintained at a temperature of 50 ° C to 80 ° C. Subsequently, the drug solution and perfluorocarbon emulsion are combined and fed into the spray dryer. Normally, the two preparations can be miscible, since the emulsion will preferably comprise an aqueous continuous phase. Although, for the purposes of the present disclosure, the bioactive agent is solubilized separately, it will be appreciated that, in other embodiments, the bioactive agent can be solubilized (or dispersed) directly in the emulsion. In such cases, the bioactive emulsion is simply spray dried, without combining a drug preparation separately. In any case, the operating conditions such as inlet and outlet temperature, supply range, atomization pressure, air drying flow range, and nozzle configuration, can be adjusted according to the manufacturer's instructions, in order to produce the required particle size and the production of the resulting dry microstructures. Exemplary settings are as follows: an air inlet temperature of between 60 ° C and 170 ° C, an air outlet temperature of between 40 ° C to 120 ° C, a power range of between 3 mi. up to about 15 mi. per minute; and a suction setting of 300 L / min and a spray air flow range of between 1, 200 to 2,800 L / hr. The selection of suitable apparatus and processing conditions, by virtue of the techniques described herein, are within the competence of one skilled in the art and can be carried out without undue experimentation. In any case, the use of these and of substantially equivalent methods, provide the formation of hollow, porous and aerodynamically light microspheres, with particle diameters suitable for deposition by means of aerosol in the lung. As described above, said particles are particularly effective in the formation of stabilized dispersions which are extremely compatible with the inhalation systems and misting techniques which will be described in greater detail below. Along with spray drying, perforated or particulate microstructures useful in the present invention may be formed by lyophilization. Those skilled in the art will appreciate that lyophilization in a freeze drying process, in which water is sublimed from the composition after it is frozen. The particular advantage associated with the lyophilization process is that, biological and pharmaceuticals that are relatively unstable in an aqueous solution, can be dried without high temperatures (thus eliminating the adverse thermal effects), and then stored in a dry state where there are some stability problems. With respect to the present invention, said techniques are particularly compatible with the incorporation of peptides, proteins, genetic material and other synthetic or natural macromolecules into particulate or perforated microstructures, without compromising physiological activity. It is known to those skilled in the art that methods for providing lyophilized particulates would not clearly require undue experimentation to provide compatible dispersion microstructures in accordance with the teachings described herein. Therefore, lyophilization processes that can be used to provide microstructures having the desired porosity and size are in accordance with the teachings described herein and are expressly contemplated to be within the scope of the present invention. In addition to the aforementioned techniques, the perforated microstructures or particles of the present invention can also be formed using a double emulsion method. In the double emulsion method, the drug is first dispersed in a polymer dissolved in an organic solvent (eg, methylene chloride), by sonification or homogenization. Subsequently, this primary emulsion is stabilized by forming a multiple emulsion in a continuous aqueous phase containing an emulsifier such as polyvinylalcohol. Subsequently, the organic solvent is removed by evaporation or extrac- tion, using conventional techniques and apparatus. The resulting microspheres are washed, filtered and lyophilized before dispersing in the suspension medium according to the present invention. Although particulate suspensions comprising a non-liquid dispersed phase are particularly compatible with the present invention, it will be appreciated that, as discussed above, the stabilized dispersions may also comprise liquid-in-liquid colorant systems, for example, emulsions and inverse microemulsions. Those skilled in the art will appreciate that such systems are known in the art and that stabilized dispersions compatible with the teachings described herein can be provided without undue experimentation. With respect to this, any emulsion or inverse microemulsion having the ability to be nebulized to provide a therapeutically effective aerosol for pulmonary administration, is contemplated to be within the scope of the present invention. Preferably, the emulsions will be water emulsions in fluorochemicals. That is, the selected inverse emulsion or microemulsion will preferably comprise a fluorochemical dispersion phase with the other phase which is aqueous in nature. Exemplary inverse emulsions useful with the present invention were described in U.S. Patent No. 5,770,585, U.S.S.N. 08 / 487,612 pending and U.S.S.N. 08 / 478,824 pending, with each of the above references incorporated in the present invention as reference. Said preparations can be stabilized by fluorinated or non-fluorinated surfactants. With respect to this point of the present invention, many of the fluorochemicals useful in the liquid-liquid preparations described are the same as those which are useful as suspension media in the described particulate dispersions. Therefore, although the following commentary is directed primarily to compatible suspension media for the distribution of non-liquid particles, it will be appreciated that the same compounds (eg, fluorochemicals) are useful in liquid-in-liquid dispersions that are compatible with the present invention. Therefore, although the term "means or means of suspension" will be used below, it should be understood that these same compounds may comprise emulsion phases according to the teachings described herein. Regardless of the selected colloidal system, it is an advantage of the present invention that the non-aqueous biocompatible compounds can be used as suspending media or as a continuous phase. Particularly preferred suspension means are compatible with use in nebulizers. This is that, they will have the capacity to form aerosols in the application of their energy. In general, the selected suspension medium must be biocompatible (for example, relatively non-toxic) and non-reactive with respect to the suspended perforated microstructures comprising the bioactive agent. Preferred embodiments comprise a suspension medium selected from the group consisting of fluorochemicals, fluorocarbons (including those substituted with other halogens), perfluorocarbons, fluorocarbon / hydrocarbon diblocks, hydrocarbons, alcohols, ethers or combinations thereof. It will be appreciated that, the suspension medium may comprise a mixture of several compounds selected to impart specific characteristics. It will also be appreciated that the perforated microstructures are preferably insoluble in the suspension medium, thereby providing stabilized medicament particles and, effectively protecting against degradation, which could occur during prolonged storage in an aqueous solution, to the selected bioactive agent. . In preferred embodiments, the selected suspension medium is bacteriostatic. The suspension formulation also protects the bioactive agent with degradation during the nebulization processes. As indicated above, the suspension medium can comprise any number of different compounds, including hydrocarbons, fluorocarbons or hydrocarbon / fluorocarbon diblocks. In general, the contemplated hydrocarbons or highly fluorinated or perfluorinated compounds may be linear, branched or cyclic, saturated or unsaturated compounds. The conventional structural derivatives of these fluorochemicals and hydrocarbons are also contemplated to be within the scope of the present invention. Selected embodiments comprising these fully or partially fluorinated compounds may contain one or more hetero atoms and / or bromine or chlorine atoms. Preferably these fluorochemicals comprise from 1 to 16 carbon atoms and include, but are not limited to, linear perfluoroalkanes, cyclic or polycyclic, bis (perfluoroalkyl) alkanes, perfluoroethers, perfluoroamines, perfluoroalkyl bromides and perfluoroalkyl chlorides such as dichloro-octane. Particularly preferred fluorinated compounds for use in the suspension medium, can comprise perfluorooctyl bromide CdF? 7Br (PFOB or perflubron), dichlorofluorooctane C8F15CI2 and ethano perfluorooctyl hydrofluoroalkane perfluorooctyl CSFIT ^ HS (PFOE). With respect to other embodiments, the use of perfluoroexan or perfluoropentane as the suspension medium is especially preferred. More generally, exemplary fluorochemicals which are contemplated for use in the present invention, generally include halogenated fluorochemicals (eg, C0F2o +? X, XC, F2o, where N = 2-10, x = Br, Cl or i) and, in particular b1-bromo-F-butane 1 bromo-F-hexane (n-C6F? 3Br), 1-bromo-F-heptane (n-C7F15Br), 1,4-dibromo-F-butane and 1, 6 dibromo-F-hexane. Other useful brominated fluorochemicals are described in US Patent No. 3,975,512 to Long, and are incorporated herein by reference. Also preferred are fluorochemicals having chloride substituents such as perfluorooctyl chloride (n-C8F? 7CI), 1,8-diclolo-F-octane (n-CIC8F15CI), 1,6-dicolo-F-hexane (n -CIC6F? 2CI), and 1,4-dichloro-F-butane (n-CIC4F8CI). Fluorocarbon, fluorocarbon-hydrocarbon and halogenated fluorochemical compounds containing other linking groups, such as esters, thioethers and amines, are also suitable for use as suspending medium in the present invention. For example, are they compatible with the teachings described herein, the compounds having the general formula CnF2n +? OCmF2m +? or C0F20 + 1 = CHCmF2m + i2 (as for example C4FgCH = CHC4Fg (F-44E), -C3F9CH = CHC6Fi3 (F-136E) Y, C5F13CH = CHC6F13 8F-66E), where n and m are the same or different and n and m are members from from about 2 to about 12. The fluorochemical-hydrocarbon triblock and triblock compounds include those with the general formulas CnF2n +? CmH2m +? and CnF2r? +? CmH2m +? where n = 2-12; m = 2-16 or CpH2p + 1-CnF2nCmH2m + ?, where p = 1-12, m = 1-12 and n = 2-12. Preferred compounds of this type include C8F? 7C2H5 C6F13C10H21 C8F17C8H? 7 C5F13CH = CHC6H13 and C? F? 7CH = CHC10H21. Substituted ethers or polyethers can also be used (for example XCnF2nOCmF3mX, XCFOCnF2nOCF2X, where nym = 1.4, X = Br, Cl or I) and, diblocks or triblock hydrochloride-hydrocarbon (for example, CnF2n +? OCmH2m + 1, in where n = 2-10; m = 2-16 or CpH2p +? O-CnF2n-O-CmH2m +? where p = 2-12, m = 1-12 and n = 2-12), as well as CnF2p +? O-CmF2mOCpH2P + ?, where n, myp are dedse 1-12. Additionally, depending on the application, the perfluoroalkylated ethers or polyethers may also be compatible with the claimed dispersions. Polycyclic and cyclic fluorochemicals, such as C-ioFs (F-decalin or perfluorodecalin), perfluoroperidropenanthrene, perfluorotetramethylcyclohexane (ap-144) and perfluoro n-butyldecalin, are also within the scope of the present invention. Additional useful fluorochemicals include perfluorinated amines such as F-tripropylamine ("FTPA") and F-tributylamine ("FTBA"), F-4-metriloctahydroquinolizine ("FMOQ"), FN-methyl-decahydroisoquinoline ("FMIQ"), FN-methyldehydroquinoline ("FHQ"), FNcγclohexylpyrrolidine ("FCHP") and F-2-butyltetrahydrofuran ("FC-75" or "FC-77"). Still other useful fluorinated compounds include perfluoropenanthrene, perfluoromethyldealcaine, perfluorodimetrylethylcyclohexane, perfluorodimethyldealkaline, perfluorodiethyldecaline, perfluoromethylamantana, perfluorodimethylamantane. Other contemplated fluorochemicals having nonfluorine substituents, such as perfluorooctyl hydrido and similar compounds having different numbers of carbon atoms are also useful. Those skilled in the art will further appreciate that other variously modified fluorochemicals are carried out within the broad definition of fluorochemicals as used in the present application and are suitable for use in the present invention. Therefore, they can be used alone or in combination with other compounds, each of the above compounds to form the stabilized dispersions of the present invention. Specific fluorocarbons or classes of fluorinated compounds which may be useful as a suspending medium, include but are not limited to fluoroheptane, fluorocycloheptane, fluoromethylcycloheptane, fluorohexane, fluorocyclohexane, fluoropenane, fluorocyclopentane, fluoromethylcyclopentane, fluorodimethylcyclopentanes, fluoromethylcyclobuthane, fluorodimethylcyclobutane, fluorotrimetrilcylbutane, fluorobutane, fluorocyclobutane. , fluoropropane, fluoroethers, fluoropolyethers and fluorotriethylamines. These compounds are generally studied environmentally and are biologically incompatible. Although any liquid compound having the ability to produce an aerosol in the application of energy, can be used in conjunction with the present invention, the selected suspension medium will preferably have a vapor pressure less than about 5 atmospheres and more preferably less than about 2 atmospheres Unless otherwise specified, all vapor pressures cited in the present invention are measured at 25 ° C. In other embodiments, the suspension means may be used in conjunction with compressed air nebulizers, ultrasonic nebulizers or mechanical atomizers, to provide effective ventilation therapy. In addition, the more volatile compounds can be mixed with the lower vapor pressure components, to provide suspension media having specified physical characteristics, selected to further improve the stability or improve the bioavailability of the dispersed bioactive agent. Other embodiments of the present invention will comprise suspension means that bulge at selected temperatures under ambient conditions (e.g., 1 atm). For example, preferred embodiments will comprise compounds of suspension media that bulge above 0 ° C, above 5 ° C, above 10 ° C, above 15 ° C or above 20 ° C. In other embodiments, the compound of the suspension media may boil at or above 25 ° C or above 30 ° C. Still in other embodiments, the selected suspension media may bubble at or above human body temperature (e.g., 37 ° C), above 45 ° C, 55 ° C, 65 ° C, 75 ° C, 85 ° C or above 100 ° C. It will be further appreciated that one of ordinary skill in the art can readily determine other compounds that would function properly in the present invention, which appear or exhibit a desirable vapor pressure and / or viscosity. Rather, it will be clear that certain compounds that are outside the preferred ranges of vapor pressure or viscosity can be used if they provide the desired aerosolized medicament. The stabilized suspensions or dispersions of the present invention can be prepared by dispersing the microstructures in the selected suspension medium, which can then be placed in a container or container. With respect to this, the stabilized preparations of the present invention can be made by simply combining the components in an amount sufficient to produce the desired final dispersion concentration. Although the microstructures are easily dispersed without mechanical energy, the application of mechanical energy is contemplated to help in the dispersion (for example with the help of sonification), particularly for the formation of stable emulsions or inverse emulsions. Alternatively, the components can be mixed by stirring them in a simple manner or with another type of agitation. To make clear any adverse effects of moisture on the stability of the suspension, the process is preferably carried out under anhydride conditions. Once the dispersion is formed, it has a reduced susceptibility to flocculation or sedimentation. It will also be clear that other components may be included in the pharmaceutical compositions of the present invention. For example, osmotic agents, stabilizers, chelators, buffers, viscosity modulators, salts and sugars can be added to fine-tune the stabilized dispersions for maximum life and easy administration. Said components can be added directly to the suspension medium, ether phase of an emulsion or, associated with or incorporated in dispersed particles or perforated microstructures. Considerations such as sterility, isotonicity and biocompatibility can govern the use of conventional additives for the compositions described. For those skilled in the art, the use of such agents will be clear and the quantities, proportions and types of specific agents can be determined empirically without undue experimentation. The administration of the bioactive agent may be indicated by the treatment of mild, moderate or severe, acute or chronic symptoms or by prophylactic treatment. In addition, the bioactive agent can be administered to treat local or systemic conditions or disorders. It will be appreciated that the precise dose administered will depend on the age and conditions of the patient, the particular medication used and the frequency of administration, and ultimately will depend on the judgment of the attending physicist. When combinations of bioactive agents are used, generally the dose of each component of the combination will be the one used by each component when used alone.As discussed throughout the specification, the stabilized dispersions described herein, are preferably administered to the lung or pulmonary air passages of a patient, through aerosolization, such as with a nebulizer. Nebulizers are well known in the art and could be readily employed for the administration of the claimed dispersions without undue experimentation. They are also compatible with the stabilized dispersions of the present invention and are contemplated to be within the scope thereof, the respiratory activated nebulizers, as well as those comprising other types of improvements that have been, or will be, developed. Although compatible bioactive agents can be administered using various systems, it will be appreciated that, particularly in the preferred embodiments, the stabilized dispersions described herein will be administered, via nebulization, to the lung or pulmonary air passages of a patient. Nebulizers are well known in the art and could be readily employed for the administration of the claimed dispersions without undue experimentation. Nebulizers work by forming aerosols, that is, turning a liquid into volume into small droplets suspended in a breathing gas. Here, the aerosolized medicament to be administered (preferably to the pulmonary air duct), will comprise small droplets of the suspension medium associated with relatively non-porous particles, perforated microstructures or with the liquid dispersion phase comprising a bioactive agent. In said embodiments, the stabilized dispersions of the present invention will normally be placed in a container of associated liquid in operable form with a nebulizer. The specific preparation volumes provided, the means for filling the container, etc., will largely depend on the selection of the individual nebulizer and are well known to those skilled in the art. Of course, the present invention is completely compatible with single dose nebulizers and multiple dose nebulizers. In any case, the intermediate aerosolization of the nebulizer normally requires an input of energy in order to produce the surface area of the increased droplets and, in some cases, to provide the transport of the atomized or aerosolized medicament. A common mode of aerosolization is pushing a stream of liquid that will be expelled from a nozzle, where the drops are formed. With respect to nebulized administration, additional energy is usually imparted to provide drops that are small enough to be transported to the deep lungs. Therefore, additional energy is needed, such as that provided by a high-speed gas stream or by a piezoelectric cirstal. Two popular types of nebulizers, jet nebulizers and ultrasonic nebulizers, depend, during atomization, on the aforementioned methods of applying additional energy to the fluid. The jet nebulizer is well known and widely used. In a jet nebulizer, the compressed air is pushed into an apparatus comprising a liquid to be aerosolized, such as one of the suspensions of the present invention. The compressed air draws the liquid through one or more small openings, thus generating the aerosol. The high speed of the compressed air, provides enough energy to make possible the formation of drops small enough for inhalation. To help the formation of evenly smaller droplets, the droplets are initially impacted against baffle. There may be other impact sites, to which the droplets may be directed, before the aerosol of the nebulizer is carried out, by the flow of compressed air. In the preferred modalities, the compressed air can be saturated with the suspension medium. This would allow aerosolized droplets to be deposited in the lung, possibly facilitating improved dispersion of the bioactive agent after initial deposit. The ultrasonic nebulizers do not require the use of compressed air and, therefore, can be similar to the IDMs, in terms of compactness and portability, although they operate under different physical principles. Preferred ultrasonic nebulizers are those both small, portable, energized by batteries and have the ability to administer some doses, each comprising a simple bolus of aerosolized solution. These nebulizers can be qualified simple bolus nebulizers. Most devices are operated manually, but some devices act by breathing. The devices that act by breathing work, releasing aerosol when the device perceives the inhalation of the patient through a circuit. Breathing nebulizers can also be placed in line on a ventilation circuit to release aerosol into the airflow, which comprises the gases of inspiration for a patient. The core of most ultrasonic nebulizer species is a transducer made from a piezoelectric crystal. When the oscillating energy is applied to the piezoelectric crystal, it will vibrate at the same frequency as the applied energy, which is preferably within the ultrasonic range. This movement, when transmitted in a liquid, provides the energy needed to aerosolize the liquid. The size of the drop (a medium diameter is counted) formed by this method, is a function of the excitation frequency, the density of the liquid and the tension of the liquid surface, while the atomization range is a function of viscosity, surface tension and vapor pressure. One type of nebulizer is the Respimart (Boehringer Ingelheim, Germany), which operates manually, is portable and is operated by batteries. When the patient squeezes a trigger on the apparatus, a drop of solution (approximately 100 I) is measured on a piezoelectric plate approximately 1 cm in diameter. When energy is applied, the plate vibrates at approximately 10 MHz, resulting in the aerosolization of the solution, which can subsequently be inhaled by a patient.

Another type of ultrasonic nebulizer is the AeroDose (AeroGen, Sunnyvale, CA). (DeYoung, "The AeroDose Multidose Inhaler Device Desing and Delivery Characteristics," Respiratory Drug Delivery VI, 1998, p.91). The AeroDose operated by battery, operates through a plate that contains several hundred holes that vibrate at ultrasonic frequencies. When the upper part of the apparatus is pressed down, a metering pump delivers a dose of liquid from a canister to the plate. The device acts by breathing, with aerosolization beginning when the device senses the patient's inspiration. The researchers of the AeroDose nebulizer, report that, using this device, they have the capacity to achieve a medium mass aerodynamic diameter of from 1.9 to 2.0 m. Still another type of ultrasonic nebulizer is that described in PCT International Publication No. WO92 / 11050 for Robertson and associates. In Robertson's apparatus, the solution or other material to be nebulized is extracted through numerous thin holes found in a metal plate, which vibrates by the use of a piezoelectric device. When energy is applied, the aerosol is formed and will continue to form as long as the energy is delivered to the piezoelectric crystal. Therefore, depending on the amount of time the device is left on, it can serve as either a simple bolus device or as a continuous nebulizer. As noted above, the nebulization devices can act by ultrasonic energy alone, or they can use ultrasonic energy in combination with other aerosolization methods such as pressure or extraction of a liquid or suspension, through a material with very small openings . Still, without considering the type of nebulizer selected, the stabilized dispersions of the present invention provide a significant advantage due to their relatively homogeneous dispersion of the incorporated bioactive agent, over a period of time. That is, the homogeneous dispersion of the incorporated particulates, ensures that the amount of bioactive agent administered, is consistent no matter what fraction, of the preparation in the fluid container, is actually nebulized in each individual actuation of the nebulizer. Similarly, when used for continuous administration over a prolonged period, the homogeneous, stable dispersions of the present invention ensure that relatively constant levels of bioactive agent are administered during each increasing time period. In any case, it should be noted that the examples of previous foggers are only by way of example. As will be appreciated by one skilled in the art, other types of nebulizers, whether recently known or recently invented, may also be used for the administration of the stabilized dispersions of the present invention. It will be appreciated that stabilized preparations for use in nebulizers of the present invention can be advantageously delivered to physicists or other health care professionals in a package form or sterile equipment. More particularly, the formulations can be supplied as stable, pre-formed dispersions ready for administration or, separately, ready for mixing the components. When the dispersions are provided in a ready-to-use form, they can be packaged in single-use containers or containers, as well as in containers or multi-use containers. In either case, the container or container may be associated with the selected nebulizer and used as described in the present invention. When provided in the form of individual components, (for example, as powdered microspheres and as a fine suspension medium), then stabilized preparations can be formed at any time before being used., simply combining, as indicated, the contents of the containers. Additionally, said equipment may contain a number of components ready to be mixed or pre-packaged, which can be individually packaged so that the user can later select the desired component (s) for the particular indication or use. With respect to this, the user may subsequently substitute the selected components during a particular course of treatment, as indicated or as indicated. It will also be appreciated that such equipment may optionally include a nebulizer or preparation that may be delivered in a disposable nebulizer. The above description will be better understood with reference to the following Examples. However, said Examples are merely representative of the preferred practice methods of the present invention and, should not be understood as limiting the scope thereof.

Preparation of Porous Hollow Particles of Gentamicin Sulfate by Spray Drying 40 to 60 ml of the following solutions were prepared by spray drying: 50% w / w hydrogenated phosphatidylcholine, E-100-3 (Lipoid KG, Ludwigshafen, Germany) 50% w / w of gentamicin sulfate (Amresco, Solon, OH) Perfluorooctilbromide, Perflubron, (NMK, Japan) Deionized Water Perforated microstructures comprising gentamicin sulfate, were prepared by a spray-drying technique, using a Mini Dryer by Rocío B-191 (Büchi, Flawil, Switzerland), under the following conditions: suction: 100%, inlet temperature: 85 ° C, outlet temperature: 61 ° C; Feeding pump: 10%, N2 flow: 2,800 L / hr. The variations in the porosity of the powder were examined as a function of the concentration of the blowing agent. Fluorocarbon emulsions in perfluorooctyl bellow water containing a 1: 1 w / w ratio of phosphatidylcholine (PC) and gentaminicin sulfate were prepared by varying only the PFC / PC ratio. 1. 3 grams of hydrogenated egg phosphatidylcholine were dispersed in 25 mL of deionized water using an Ultra-Turrax mixer (model T-25) 8000 rpm for 2 to 5 minutes (T = 60-70 ° C). During the mixing, perflubron droplets were added in a range of from 0 to 40 grams (T = 60-70 ° C). After the addition was completed, the fluorocarbon emulsion in water was mixed for an additional period of not less than 4 minutes.

Subsequently, the resulting thick emulsions were homogenized under high pressure, with an Avestin homogenizer (Ottawa, Canada) under a pressure of 15,000 psi for 5 passes. Gentamicin sulfate was dissolved in approximately 4 to 5 mL of deionized water and subsequently mixed with the perflubron emulsion immediately before the spray drying process. Subsequently, the gentamicin powders were obtained by spray drying, using the conditions described above. A pale yellow powder of free flow was obtained for all the perflubron contained in the formulations. The production for each of the different formulations was within the range of 35% to 60%.

Morphology of Gentamicin Sulphate Spray Dried Powders A large dependence on powder morphology, porosity degree and production was observed, as a function of the PFC / PC ratio, by the electron scanning microscope (SEM) ). In the column on the left side of Figure 1, a series of six SEM micrographs are shown, which illustrate these observations, identified from 1A1 to 1 F1. As it was observed in these micrographs, it was discovered that the porosity and roughness of the surface depend in large part on the concentration of the blowing agent, where the surface roughness, the number and size of the pores increased with the increase of the proportions PFC / PC. For example, the formulation devoid of perfluorooctyl bellows produced microstructures that appeared to be highly agglomerated and easily adhered to the surface of the glass bottle. Similarly, soft, spherical microparticles were obtained when the relatively small blowing agent was used (ratio PFC / PC = 1.1 or 2.2). As the PFC / PC ratio increased, the porosity and roughness of the surface increased dramatically. As shown in the column on the right side of Figure 1, the hollow nature of the microstructures was also improved by incorporating the additional blowing agent. More particularly, the series of six micrographs identified from 1A2 to 1 F2 shows the cross sections of the fractured microstructures as revealed by the electron transmission microscope (TEM). Each of these images, was produced using the same microstructure preparation that was used to produce the corresponding SEM micrograph, which is found in the left side column. Both the hollow nature and the wall thickness of the perforated microstructures appeared to be larger depending on the concentration of the selected blowing agent. That is, the hollow nature of the preparation seemed to increase and the thickness of the particle walls seemed to decrease as the PFC / PC ratio increased. As seen in Figures 1A2 through 1C2, substantially solid structures were obtained from formulations containing little or no fluorocarbon blowing agent. Conversely, the perforated microstructures were produced using a relatively high PFC / PC ratio of approximately 45 (illustrations of Figure 1 F2, proved to be extremely hollow with a relatively thin wall being within the range of from about 43.5 to 261 nm). Both types of particles are compatible for use in the present invention.

Preparation of Albuterol Sulphate Porous Porous Particles by Spray Drying Porous, porous albuterol sulphate particles were prepared by a spray drying technique with a Mini Spray Dryer (Büchi, Flawil, Switzerland), under the following conditions dew point: aspiration: 100%, inlet temperature: 85 ° C; outlet temperature: 61 ° C; Feeding pump: 10%, N2 flow: 2,800 L / hr. The feed solution was prepared by mixing two solutions A and B immediately before spray drying. Solution A: 20 g of water was used to dissolve 1 g of albuterol sulfate (Accurate Chemical, Westbury, NY) and, 0.021 g of 188 NF poloxamer (BASF, Mount Olive, NJ). Solution B: was prepared in the following manner a fluorocarbon emulsion in water stabilized by phospholipid. The phospholipid, 1g EPC-100-3 (Lipoid KG, Ludwigshafen, Germany), was homogenized in 150g of deionized hot water (T = 50 to 60 ° C), using an Ultra-Turrax mixer (model T-25) at 8000 rpm for 2 to 5 minutes (T = 60-70 ° C). During the mixture, 25 g were added in perfluorooctyl bromide droplets (Atochem, Paris, France). After the fluorocarbon was added, the emulsion was mixed for a period of not less than 4 minutes. Subsequently, the resulting coarse emulsion was passed through a high pressure homogenizer (Avestin, Ottawa, Canada) at 18,000 psi for 5 passes.

Solutions A and B were combined and fed into the spray dryer under the conditions described above. A white powder flowing freely in the cyclone separator was collected. The hollow, porous albuterol sulfate particles had an average aerodynamic diameter of heavy volume of 1.18 ± 1.42 μm, as determined by a time-of-flight analytical method (Aerosizer, Amherst Process Instruments, Amherst, MA). The analysis of the electron scanning microscope (SEM) showed that the powders are spherical and highly porous. The density of the dust cover was determined, less than 0.1 g / cm3. The above examples serve to illustrate the inherent diversity of the present invention as a drug administration capable of effectively incorporating any number of pharmaceutical agents. Additionally, the principle is shown in the following example.

IV Formation of Porous Particulate Microstructures comprising Blends of Long Chain / Short Chain Phospholipids and Albuterol Sulfate A dispersion was prepared for spray drying as described above, with the difference that 1 g of DSPC was dispersed with 10 mg of a short chain phospholipid, dioctyphosphatidylcholine (DOPC) (Avanti Polar Lipids, Alabaster, Alabama). The composition of the spray feed is shown in Table II below.

V Preparation of Porous Hollow Particles of Cromolin Sodium by Spray-drying Perforated microstructures comprising cromolin sodium were prepared by a spray-drying technique with a Mini Dryer by Dew B-191 (Büchi, Flawil, Switzerland), under the following spray conditions: suction: 100%, inlet temperature: 85 ° C, outlet temperature: 61 ° C, feed pump. 10%, N2 flow: 2,800 L / hr The solution was prepared by mixing the two solutions A and B, immediately before the spray drying. Solution A: 20 g of water was used to dissolve 1 g of cromolyn sodium (Sigma Chemical Co., St. Louis, MO) and, 0.021 g of poloxamer grade 188 NF (BSF, Mount Olive, NJ). Solution B: A stabilized emulsion of fluorocarbon in water by phospholipid was prepared in the following manner. The phospholipid, 1 g EPC-100-3 (Lipoid KG, Ludwigshafen, Germany), was homogenized in 150 g of deionized hot water (T = 50 to 60 ° C), using an Ultra-Turrax mixer (model T-25) to 8000 rpm for 2 to 5 minutes (T = 60-70 ° C). During the mixing they were added, 27g in perfluorodecalin drops (Air Products, Allentown, PA). After the fluorocarbon was added, the emulsion was mixed for at least 4 minutes. Subsequently, the resulting coarse emulsion was passed through the high pressure homogenizer (Avestin, Ottawa, Canada) at 18,000 psi for 5 passes. Solutions A and B were combined and fed into the spray dryer under the conditions described above. A pale yellow powder flowing freely in the cyclone separator was collected. The hollow and porous cromolyn sodium particles had an average aerodynamic diameter of heavy volume of 1.23 ± 1.31 μm, as determined by a time-of-flight analytical method (Aerosizer, Amherst Process Instruments, Amherst, MA). As shown in Figure 2, the scanning electron microscope (SEM) analysis showed that the powders are both hollow and porous. The density of the dust cover was determined, less than 0.1 g / cm3.

SAW Preparation of Porous and Hollow Particles of BDP by Spray Drying The microspheres comprising beclomatasone dipropionate particles were prepared by a spray-drying technique with a Mini Air Dryer B-191 (Büchi, Flawil, Switzerland) under the following spray conditions: suction: 100%, inlet temperature: 85 ° C, outlet temperature: 61 ° C, feed pump. 10%, N2 flow: 2,800 L / hr. The feeding cell was prepared immediately before the spray drying, mixing 0.11 g of lactose with a fluorocarbon emulsion in water. The emulsion was prepared, by the technique that follows. They were dissolved in 2 ml of hot methanol, 74 mg of BDP (Sigma, Chemical Co., St. Louis, MO), 0.5 g of EPC-100-3 (Lipoid Kg, Ludwigshafen, Germany), 15 mg of sodium oleate. (Sigma) and, 7 mg poloxamer 188 (BASF, Mount Olive, NJ). Subsequently the methanol was evaporated to obtain a thin film of the phospholipid / steroid mixture. Subsequently the phospholipid / steroid mixture was dispersed in 64 g of deionized hot water (T = 50 to 60 ° C), using an Ultra-Turrax mixer (model T-25) at 8000 rpm for 2 to 5 minutes (T = 60-70 ° C). 8 g of perflubron droplets were added during mixing (Atochem, Paris, France). After the addition was completed, the emulsion was mixed for an additional period of not less than 4 minutes. Subsequently the resulting coarse emulsion was passed through a high pressure homogenizer (Avestin, Ottawa, Canada) at 18,000psi for 5 passes. Subsequently this emulsion was used to form the feed pile, which was spray dried as described above. A freely flowing white powder was collected in the cyclone separator. The hollow, porous, BDP particles had a lid density of less than 0.1 g / cm 3.

Vile Preparation of the hollow particles. Porcelain from TAA. by Spray Drying The microstructures comprising triamcinolone acetonide particles (TAA), were prepared by a spray-drying technique with a Mini Dryer by Dew B-191 (Büchi, Flawil, Switzerland) under the following dew conditions: suction : 100%, inlet temperature: 85 ° C, outlet temperature: 61 ° C, feed pump. 10%, N2 flow: 2,800 L / hr. The feeding cell was prepared immediately before the spray drying, mixing 0.57 g of lactose with a fluorocarbon emulsion in water. The emulsion was prepared, by the technique that follows. They were dissolved in 2 ml of hot methanol, 100 mg of TAA (Sigma, Chemical Co., St. Louis, MO), 0.56 g of EPC-100-3 (Lipoid Kg, Ludwigshafen, Germany), 25 mg of sodium oleate. (Sigma) and, 13 mg poloxamer 188 (BASF, Mount Olive, NJ). Subsequently the methanol was evaporated to obtain a thin film of the phospholipid / steroid mixture. Subsequently the phospholipid / steroid mixture was dispersed in 64 g of deionized hot water (T = 50 to 60 ° C), using an Ultra-Turrax mixer (model T-25) at 8000 rpm for 2 to 5 minutes (T = 60-70 ° C). 8 g of perflubron droplets were added during mixing (Atochem, Paris, France). After the addition was completed, the emulsion was mixed for an additional period of not less than 4 minutes. Subsequently the resulting coarse emulsion was passed through a high pressure homogenizer (Avestin, Ottawa, Canada) at 18,000psi for 5 passes. Subsequently this emulsion was used to form the feed pile, which was spray dried as described above. A freely flowing white powder was collected in the cyclone separator. The porous hollow particles TAA had a density of less than 0.1 g / cm3.

VIII Preparation of the hollow particles. Porous of DNsa I. by Drying by Dew The hollow, porous DNsa I particles were prepared by a spray drying technique with a Mini Dryer by Dew B-191 (Büchi, Flawil, Switzerland), under the following spray conditions: suction: 100%, inlet temperature: 80 ° C, outlet temperature: 61 ° C, feed pump. 10%, N2 flow: 2,800 L / hr. The feed was prepared by mixing the two solutions A and B, immediately before the spray drying. Solution A: 20 g of water were used to dissolve 0.5 g of DNase I (CalBiochem, San Diego CA) and 0.012 g of poloxamer grade 188 NF (BSF, Mount Olive, NJ). Solution B: A stabilized emulsion of fluorocarbon in water through phospholipid was prepared in the following manner. The phospholipid, 0.52 g EPC-100-3 (Lipoid KG, Ludwigshafen, Germany), was homogenized in 87g of deionized hot water (T = 50 to 60 ° C), using an Ultra-Turrax mixer (model T-25) to 8000 rpm for 2 to 5 minutes (T = 60-70 ° C). During the mixture, 13 g were added in perflubron drops (Atochem, Paris, France).

After the fluorocarbon was added, the emulsion was mixed for at least 4 minutes. Subsequently, the resulting coarse emulsion was passed through the high pressure homogenizer (Avestin, Ottawa, Canada) at 18,000 psi for 5 passes. Solutions A and B were combined and fed into the spray dryer under the conditions described above. A pale yellow powder flowing freely in the cyclone separator was collected. The hollow and porous DNase particles had an average aerodynamic diameter of heavy volume of 1.29 ± 1.40 μm, as determined by a time-of-flight analytical method (Aerosizer, Amherst Process Instruments, Amherst, MA). Analysis of the electron scanning microscope (SEM) showed that the powders are both hollow and porous. The density of the dust cover was determined, less than 0.1 g / cm3. The above example further illustrates the extraordinary compatibility of the present invention with a variety of bioactive agents. That is, in addition to relatively small hard compounds such as steroids, the preparations of the present invention can be formulated to incorporate larger and brittle molecules such as peptides, proteins and genetic material.

IX Preparation of hollow dust, pores by spray drying a gas emulsion in water The following solutions were prepared with water by injection: Solution 1: 3. 9% w / v hydroxyethyl starch m-HES (Ajinomoto, Tokyo, Japan) 3.25% w / v Sodium chloride (Mallinckrodt, St.Louis, MO) 2.83% w / v Sodium phosphate, dibasic (Mallinckrodt, St. Louis, MO) 0.42% w / v Sodium phosphate, monobasic (Mallinckrodt, St. Louis, MO) Solution 2: 0. 45% w / v Poloxamer188 (BASF, Mount Olive, NJ) 1.35% w / v Hydrogenated egg phosphatidylcholine, EPC-3 (Lipoid KG, Ludwigshafen, Germany) The ingredients of solution 1 were dissolved in warm water, using a stir plate. The surfactants in solution 2 were dispersed in water using a top cut mixer. The solutions were combined, following the emulsification and, they were saturated with nitrogen before spray drying. The resulting free-flowing, hollow, spherical, dry product had an average particle diameter of 2.6 ± 1.5 μm. The particles that can be used for the replacement or increase of the pulmonary surfactant were spherical and porous as determined by SEM. The above example shows the point at which a wide variety of blowing agents (in this case nitrogen) can be used to provide microstructures exhibiting the desired morphology. Actually, one of the main advantages of the present invention is the ability to alter the formation conditions, so as to preserve the biological activity (for example, with proteins or pulmonary surfactant) or, to produce microstructures having a selected porosity.

X Preparation of Perforated Mycorestructures Powder Containing Ampicillin The materials listed below were obtained and used to provide a feeding cell: % w / w Ampicillin, Biotech grade (Fisher Scientific, Pittsburgh, PA) 14.38% w / w Hydroxyethyl starch (Ajinomoto, Japan) 65.62% w / w Dipalmitoylphosphatidylcholine (Genzyme, Cambridge, MA) Perfluorohexane (3M, St. Paul, MN) Deionized water Hydroxyethyl starch (HES, 0.9 g) and dipalmitoylphosphatidylcholine (DPPC, 4.11 g) were dispersed in 75 ml of deionized water, using an Ultra-Turrax mixer (model T-25) at 10,000 rpm for approximately 2 minutes (T = 45-50c). The resulting DPPC / HES dispersion was cooled in an ice bath. Ampicillin (1.25g) was added and left to mix for 1 minute (T 0 5-10C). Subsequently during mixing (T = 5-10 C) perfluorohexane was added dropwise (PHF, 4.11 g). After the addition was completed, the PFH emulsion in water was mixed in the Ultra-Turrax mixer for a total of not less than 4 minutes. A perforated microstructure powder comprising amplicillin was obtained, drying by dew (Büchi, 191 Mini Dryer by Rocío, Switzerland) ampicillin containing emulsion in a range of 5.5 ml / min. The inlet and outlet temperatures of the spray dryer were 90 ° C and 55 ° C respectively. The air of nebulization and the flow of aspiración fuer of 1, 800 L / hr and 100% respectively. A free-flowing white powder was obtained, which comprises porous microspheres.

XI Effect of Spray Drying of the In-Vitro Activity of the Pulmonary Surfactant The activity of a spray-dried pulmonary surfactant preparation, to reduce the surface tension of a pulsation bubble, was purchased with the pure pulmonary surfactant preparation. The pulmonary surfactant derived from bovine, Alveofact (Thomae, Biberach, Germany) and the spray-dried pulmonary surfactant containing microlayers, were dissolved in a normal saline solution at a concentration of 10 mg / ml and allowed to incubate for 15 minutes at a time. temperature of 37 ° C. Prior to the analysis, the surfactant test solutions were shaken vigorously for 30 seconds using a Vortex mixer. The samples were analyzed according to their surface properties, using a Pulse Bubble Surfactometer at a temperature of 37 ° C (model EC-PBS-B, Electronics, Amherst, NY), following the instructions of the manufacturers. The surfactant solutions were left for adsorption at a minimum bubble diameter for 10 seconds and, the bubble cycle was carried out in automatic mode (20 cycles / minute). For each experiment, measurements were taken for approximately the first 10 cycles, then again at t = 2, 4, and 6 minutes. The main difference that was observed between the suspensions of pure surfactant and spray drying, is the range in which they adsorb to the surface of the bubble and, therefore, reduce the tension. Spray-dried materials required 6 cycles to achieve low surface tension, compared to a cycle even to the Alveofact sample. However, it was found that the magnitude of the tension in the maximum and minimum bubble diameter will be approximately the same. During the Alveofact dispersion, the tension decreased from 32mN / m in a minimum diameter to 4 mN / m in a minimum diameter in the first cycle. With the additional pulse, a constant state oscillation was reached with a maximum voltage of max 33mN / m and a minimum voltage of mn 0 to 1 mN / M. During the dispersion of spray dried microlayers, the tension decreased from 36 mN / m in a maximum diameter to 16 mN / m in a minimum diameter in the first cycle. Through the sixth pulse, the voltages max and mn were 36 and 2 mN / m respectively. Both the pure Alveofact and the spray-dried pulmonary surfactant microstructures satisfied the maximum and minimum surface tension requirements for physiologically effective pulmonary surfactants, as indicated by Notter; (RH: Notter, in Surfactant Replacement Therapy, (Eds: DH: Shapiro and RH Notter), Alan R. Liss, New York, 1989), these values should be within the range of from 35 to approximately 5 mN / m, respectively . This example shows that the compositions and methods of the present invention are particularly useful for the replacement and augmentation of pulmonary surfactant in patients who need it.

XII Preparation of Perforated Microstructure Powder Containing Insulin The following materials were obtained and used to provide a power cell: 0. 0045% w / w Human Insulin, (CalBiochem, San Diego, CA) 17.96% w / w Hydroxyethyl starch (Ajinomoto, Japan) 82.94% w / w Dipalmitoylphosphatidylcholine (Genzyma, Cambridge, MA) Perfluorohexane (3M, St. Paul, MN) Deionized water Hydroxyethyl starch (HES, 1.35 g) and dipalmitoylphosphatidylcholine (DPPC, 6.16 g) were dispersed in 100 ml of deionized water, using an Ultra-Turrax mixer (model T-25) at 10,000 rpm for approximately 2 minutes (T = 45-50C). The resulting DPPC / HES dispersion was cooled in an ice bath. Insulin (3.4 mg) was added and left to mix for 1 minute (T = 5-10C). Subsequently during mixing (T = 5-10 C) perfluorohexane was added dropwise (PHF, 6.16 g). After the addition was completed, the PFH emulsion in water was mixed in the Ultra-Turrax mixer for a total of not less than 4 minutes. Insulin microstructure powder was obtained, using a Mini Dryer by Rocío Büchi model 191 (Büchi, Switzerland). The insulin-containing emulsion was fed within a range of 5.5 ml / min. The temperatures of entrance and exit of the drier by dew were of 80IC and 45 ° C respectively. The misting air and the suction flows were 1, 800 L7hr and 1005 respectively. A free-flowing white powder was obtained, which comprises porous microspheres.

XIII Effect of Perflubron on the In-Vitro Activity of DNase I Deoxyribonuclease I of bovine pancreas (DNase I, CalBiochem, San Diego, CA), was dispersed in perfluron (1 mg / ml) and allowed to incubate for 1 hour. Subsequently the perflubron was evaporated using a Savant Speed Vac (Farmingdale, NY). The activity of the DNase treated by perflubron to separate the phosphodiester linkages from DNA was compared to an untreated DNAse preparation. Serial dilutions of a DNase solution (1 mg / ml) were combined with 50 g of DNA and dissolved in 500 L of a 10 mM Tris-HCl buffer (6.3 pH), which contained 0.15 mg / ml of CaCl and 8.77 mg / ml NaCl. The samples were placed in an orbital shake and incubated at a temperature of 37 ° C for 30 minutes. Subsequently, the DNA condition in each sample after incubation was examined electrophoretically on a 1% agarose gel, which contained etidious bromide for visualization. No difference in DNA separation was observed between the untreated DNAse I samples and those treated by perflubron.

XIV Preparation of the DNAse Microdispersion in Perflubron One milliliter of the following solution was prepared: 0.00001% w / v, of deoxibronuclease I of bovine pancreas, (DNase I), (CalBiochem, San Diego, CA) and, 0.001% was dissolved of polyvinyl pyrrolidone (PV) (Sigma, St. Louis, MO) in a solution composed of 0.121% w / v of tris (hydroxymethyl) -aminomethane (Sigma), 0.0000015% w / v, CaCl2-2H2O (Sigma) and 0.0000877% w / v, NaCl (Sigma). Before adding the DNase or PVP, the pH of the solution was adjusted to 6.3. One hundred microliters of the DNase / PVP solution was added to a 12x100mm test tube containing 5 ml of perfluorooctylethane (F-Tech, Japan). The tube was covered and immersed in a sonic bath (Branson Model 3200, Danbury, CT) for 5 seconds, to obtain a milky dispersion in perflubron. Subsequently, the suspension was evaporated to dry, using a Savant Speed Vac (Model SC 200). The resulting dry microspheres were suspended again with 7 ml of Perflubron. A DNAse / PVP suspension was obtained in milky perflubron. The analysis of particle size was performed by laser diffraction (Horiba LA-700, Irvine, CA), in the weighing by volume mode. An aliquot of from about 20 to 50 L of each sample was diluted in from 9 to 10 ml of n-dodecane. The distribution sample "3", the proportion of the refractive index of 1.1 and the fraction cell were used. The resulting microdispersion had an average droplet diameter of 2.83m. Examples XIII and XIV clearly demonstrate the feasibility of preparing enzymatically active stabilized dispersions, according to the present invention. This Example also shows the number of techniques that can be used to form compatible compatible particles in the dispersions described.

XV Preparation of Perforated Microstructure Powder Labeled as Fluorescent through Spray Drying The following materials were obtained and used to manufacture the power cell: 0. 2% w / w of Nitrobenzoyldiol Phosphatidylcholine (Avanti Polar Lipid, Alabaster, AL) 17.6% w / w hydroxyethyl starch (Ajinomoto, Japan) 82.2% w / w Dipalmitoylphosphatidylcholine (Genzyme, Cambridge, MA) Perfluorohexane (3M, St. Paul, MN) Deionized Water Dipalmitoylphosphatidylcholine (DPPC, 1g) and a nitrobenzoyldiol phosphatidylcholine (NBD-PC, 10 mg) were dissolved in 4 ml of chloroform. Subsequently the chloroform was removed using a Savant Speed Vac (Model SC 200). Subsequently, the hydroxyethyl starch, (HES, 0.9 g), diplamitoylphosphatidyl choline (DPPC, 3.19 g) and 75 ml of deionized water, were added to the thin film of DPPC / NBD-PC. Subsequently, the surfactants and starch were dispersed in the aqueous phase, using an Ultra-Turrax mixer (model T-25) at 10,000 rpm, for approximately 2 minutes (T = 45-50 C). The NBD-PC / DPPC / HES dispersion was cooled in an ice bath.

Later during the mixing process (T = 5-10C), Perfluorohexane was added in drops. Once the addition was complete, the PFH emulsion in the resulting water was mixed in the Ultra-Turrax mixer for an additional time not less than 4 minutes. The microlayer powder labeled as fluorescent was obtained by spray drying (Büchi, 191, Mini Dryer by Rocío, Switzerland). The NBD-PC / DPPC / HES containing the emulsion was fed within a range of 5.5 ml / min. The inlet and outlet temperatures of the spray dryer were 100 ° C and 65 ° C respectively. The air of nebulization and the flows of aspiration were of 1, 800 L / hr and 100% respectively. A free flowing yellow powder containing perforated microstructures was obtained.

XVI Inhalation Behavior of a Perforated Microstructure in Fluorocarbon Dispersion vs. Aqueous Liposomes The nebulization profile was evaluated as a function of the aerodynamic diameter of a dispersion of microlayers in perflubron spray-dried. a dispersion of water-based liposomes, using an Andersen Cascade Impactor. During the experiments, the compressed air served as a conveyor and as an aerosol to generate gas. An air flow range of 7.5 liters / min was established at a pressure of 20 p.s.i. The aerosols were generated with a DeVilbiss air jet nebulizer (DeVilbiss Co., Somerset, PA). The nebulizer was connected to an Andersen cascade impactor (Sierra-Andersen 1 ACFM Nonviable Ambient Particle Sizing Sampler). The dispersion of aqueous liposomes was prepared by dispersing the microlayers labeled fluorescent, prepared as set forth in Example XIV in water, followed by sonication with a Vibracell sonicator (Sonics Materials, 30 mm titanium tester), with an energy of 100 watts for 2 minutes approximately (T = 22-25 C). The same perforated microstructures were suspended in PFOB, to provide a stabilized dispersion. Four ml, 5 ml of any of the dispersions of 20 mg / ml of microplates in PFOB labeled as fluoroescent or of aqueous liposomes labeled as fluorescent were nebulized for 4 minutes. Subsequently, the 8 Phases of the impactor were washed with chloroform: methanol (2: 1 w / w). Subsequently, each extract of the Phase was transferred to a volumetric flask of 2 millimeters and s.q. to the chloroform: methanol mark (2: 1 w / w). The exrats were measured for their fluorescent content using the following conditions: px = 481 nm; gm = 528 nm and, quantified by means of comparison with an external standard curve. Table III lists the characteristics of each phase of the cascade impactor, the inhalation behavior of the nebulized microlayers and the liposomes. The distribution of the NBD-PC mass was calculated as a function of the aerodynamic diameter, using the calibration curves described by Gonda and associates (Gonda, I., Kayes, JB, Groom, CV, and Fildes, FJT; Characterization of the hydroscopic inhalation aerosols: In Particle Size Analysis 1981) (Eds.NG Stanlet-Wood, and T.AIIen), pages 31-43, Wiley Heyden Ltd, New York), which are incorporated herein by reference. as reference. The comparison of two administration vehicles revealed that the efficiency of the nebulization was greater for the liposomes. On the other hand, a higher percentage of nebulized doses could be achieved for diameters of smaller air routes, with the microstructures administered by fluorocarbon, which is the reflection of its smaller mass aerodynamic diameter (MMAD), which It was achieved thanks to its hollow, porous nature. This Example and the results shown in Table III below show clearly that a number of different colloidal systems, including both particulate dispersions and liposome preparations, are compatible with the present invention.

XVII Andersen Impactor Test During Aerosol Evaluation Performance The formulations described in Examples XVIII, XIX, XX and XXI comprising Cromolin sodium, were tested using commonly accepted pharmaceutical procedures. The method used was according to the procedure of United States Pharmacopeia (USP) (Pharmacopeial Previews (1996) 22: 3065-3098), incorporated herein by reference. The Andersen Impactor was associated with the respective nebulizer or metered dose inhaler, as established in the following examples, and with the aerosolized sample collected during a specified period. Extraction procedure. The extraction of all the plates, induction port and actuator, was carried out in closed bottles with 10 mL of a suitable solvent. The filter was installed but not tested, due to the polyacrylic binder interfered with the analysis. The trends of mass balance and particle size distribution indicated that the deposit in the filter was insignificantly small. Quantification Procedure. The cromolyn sodium was quantified by the absorption spectrocopy (spectrometer DU640 Beckman) relative to an external standard curve with the extraction of the solvent as the target. The cromolyn sodium was quantified, using the absorption peak at 326 nm. Calculation procedure. For each formulation, the mass of the drug in the apparatus, as well as on the induction port (-1) and plates (0-7) were quantified, as described above. The Fine Particle Dose and the Fine Particle Fraction were calculated according to the USP method referred to above. The deposit in the throat was defined, as the mass of drug found in the induction port and in plates 0 and 1. The average aerodynamic mass diameters (MMAD) and the standard geometrical diameters (GSD), were evaluated by adjusting the function experimental cumulative with a normal registry distribution, using a two-parameter adjustment routine. The results of said measurements are shown in the following examples.

XVIII Misting of Porous Particulate Structures Comprising Phospholipids and Cromolin Sodium in Perfluorooctylethane. using a MicroMist Nebulizer Forty milligrams of lipid-based microspheres containing 50% cromolyn by weight (as in Example V), in 10 ml of perfluorooctylethane (PFOE) were dispersed, shaking and forming a suspension. The suspension was nebulized until the fluorocarbon liquid was administered or evaporated, using a disposable Micro Mist nebulizer (DeVilbiss), using a PulmoAide air compressor (DeVilbiss). As described above, an Andersen Cascade Impactor was used to measure the size distribution of the resulting particle. The impactor was disassembled and the plates of the impactor were extracted with water. The cromolyn sodium content was measured by UV adsorption at 326nm. The fine particle fraction is the proportion of particles deposited in phases 2 through 7, for those deposited in all phases of the impactor. The fine particle mass is the weight of the material deposited in phases 2 through 7. The depth fraction of the lung is the proportion of particles deposited in phases 5 to 7 of the impactor (which are correlated with the alveoli), for those deposited in all phases. The depth mass of the lung is the weight of the material deposited in phases 5 through 7. Table IV below provides a summary of the results.

XIX Misting of Porous Particulate Structures Comprising Phospholipids and Cromolin Sodium in Perfluorooctylethane. using a Raindrop Nebulizer A number of microspheres were dispersed, as in Example V, based on lipids containing 50% sodium cromolyn, weighing 40 mg, in 10 ml of perfluorooctylethane (PFOE), shaking and forming a suspension. The suspension was nebulized until the fluorocarbon liquid was administered or evaporated, using a disposable Raindrop nebulizer (Nellcor Puritan Bennet) connected to a PulmoAide air compressor (DeVilbiss). As described in Examples XVII and XVIII, an Andersen Cascade Impactor was used to measure the size distribution of the resulting particle. Table V below provides a summary of the results.

XX Nebulization of the Cromolin Sodium Aqueous Solution The content of the plastic bottle containing an inhalation solution of dose per unit of 20 mg of cromolyn sodium in 2 ml of purified water (Dey Laboratories), was nebulized using a Micro disposable nebulizer Mist (DeVilbiss, using a PulmoAide® air compressor (DeVilbiss) The cromolin sodium solution was nebulized for 30 minutes The Andersen Cascade Impactor was used to measure the resulting particle size distribution, by the method described in Example XVII Table VI below provides a summary of the results In this regard, complaints of nebulized formulations of the fluorocarbon suspension media found in Examples XVIII and XIX will be noted, provided a percentage higher deposit deep in the lung, than the aqueous solution.

XXI Preparation of a Dosage Inhaler Cromolin Sodium Measure A quantity of hollow and porous cromolyn sodium particles preweighed and prepared in Example V, was placed in a 10 ml aluminum can and dried in a vacuum oven under flow of nitrogen for 3 to 4 hours at a temperature of 40 ° C. The amount of powder filled in the can was determined by the amount of drug required to provide a desired therapeutic effect. After this, the can was sealed by pressure, using a 50 μl DF31 / 50act valve (Valois of America, Greenwich, CT) and, filled with an HFA-134a propellant (DuPont, Wilmington De), pressing excessively through the rod. The amount of propellant in the can was determined by the can weighing process, before and after filling. Subsequently, the filled MDI was used to compare the administration of cromolyn sodium, using a metered dose inhaler and a nebulizer. More specifically, a cromolyn sodium preparation was nebulized and quantified, as described in Example XVIII. Subsequently, the MDI was associated with the impactor Andersen and downloaded. During trial 5, 5 doses were sent to the waste and 20 doses were made in the Andersen impactor. In Figure 3, a comparison of the results of the Andersen cascade impactor is shown for nebulized cromolyn sodium and cromolyn sodium administered by the MDI. As can be observed in the Figure, in plates 5-7 a significantly greater percentage of the nebulized drug was discovered, showing an improved potential during systemic administration via nebulization.

XXII Misting of Porous Particle Structures Comprising Mixtures of Long Chain / Short Chain Phospholipids and Albuterol Sulfate in Perflubron To further demonstrate the diversity of the present invention, the spray dried powder of Example IV was dispersed in perflubron (Atochem, France ) at a concentration of 0.2wt%. The resulting stabilized dispersion showed no visible sedimentation for 30 minutes and could easily be nebulized with a Pulmo-Neb Disposable Nebulizer (DeVilbiss, Somerset, PA). An important deposit of dust, as was appreciated by visual inspection, was discovered on plates 4 and 5 of an Andersen cascade impactor, indicating that significant deposition is likely in the secondary and terminal human bronchus.

Those skilled in the art will further appreciate that the present invention can be included in other specific forms, without departing from the spirit or central attributes thereof. In the above description of the present invention, only exemplary embodiments thereof are described, it being clear that other variations are contemplated to be within the scope of the present invention. Therefore, the present invention is not limited to the embodiments that have been described in detail in the present invention. Rather, the appended claims should be taken as reference to the scope and content of the present invention.

CLAIMING IS

Claims (50)

Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property:

1. The use of a fluorochemical liquid in the manufacture of a medicament for the pulmonary administration of a bioactive agent, wherein the medicament comprises a stabilized dispersion having a continuous fluorochemical phase, which is nebulized using a nebulizer to form an aerosolized medicament comprising said bioactive agent, wherein said aerosolized medicament is in a form such that it can be administered to at least a portion of the pulmonary air passages of a patient in need thereof.

2. The use as described in Claim 1, further characterized in that said stabilized dispersion comprises a reverse emulsion, microemulsion or a particulate dispersion.

3. The use as described in Claim 1, further characterized in that said stabilized dispersion comprises a plurality of suspended particulates in said continuous fluorochemical phase, wherein said particulates are selected from a group consisting of micronized particles, nanocrystals, spray-dried microspheres. , perforated microstructures and combinations thereof.

4. The use as described in Claim 1, further characterized in that said stabilized dispersion comprises a plurality of perforated microstructures suspended in said continuous fluorochemical phase.

5. The use as described in Claim 4, further characterized in that said perforated microstructures comprise a surfactant.

6. The use as described in Claim 5, further characterized in that said surfactant is selected from the group consisting of phospholipids, non-ionic detergents, non-ionic block copolymers, ionic surfactants, biocompatible fluorinated surfactants and combations thereof.

7. The use as described in Claims 5 or 6, further characterized in that said surfactant is a phospholipid.

8. The use as described in Claim 7, further characterized in that said phospholipid is selected from the group consisting of dilauroylphosphatidylcholine, dioleylphosphatidylcholine, dipalmitoylphosphatidylcholine, disteroylphosphatidylcholine, benoxylphosphatidyl choline, arachididoylphosphatidylcholine and combinations thereof.

9. The use as described in claims 4 to 8, further characterized in that the average aerodynamic diameter of the perforated microstructures is between 0.5 and 5 μm.

10. The use as described in any one of claims 1 to 9, further characterized in that said bioactive agent is selected from the group consisting of anti-allergens, bronchodilators, lung surfactants, analgesics, antibiotics, leukotriene inhibitors or antagonists, antistamines. , anti-inflammatories, antineoplastic, anticholinergic, anesthetic, anti-tuberculous, imaging agents, cardiovascular agents, enzymes, steroids, genetic material, viral vectors, anti-perception agents, proteins, peptides and combinations thereof.

11. The use as described in any of Claims 1 to 10, further characterized in that said bioactive agent is administered to the systemic circulation of said patient.

12. A method for forming a stabilized respiratory dispersion comprising the steps of: combining a plurality of perforated microstructures comprising at least one bioactive agent with a predetermined volume of a non-aqueous suspension medium, to provide a respiratory mixture wherein said medium of suspension penetrates said microstructures; and mixing process of said respiratory mixture, to provide a substantially homogeneous respiratory dispersion.

The method as described in Claim 12, further characterized in that said perforated microstructures comprise a surfactant.

14. The method as described in Claim 13, further characterized in that said surfactant is selected from the group consisting of phospholipids, non-ionic detergents, non-ionic block copolymers, ionic surfactants, biocompatible fluorinated surfactants, and combinations thereof.

15. The method as described in Claim 13 or 14, further characterized in that said surfactant is a phospholipid.

16. The method as described in Claim 15, further characterized in that said phospholipid is selected from the group consisting of dilauroylphosphatidylcholine, dioleylphosphatidylcholine, dipalmitoylphosphatidylcholine, disteroylphosphatidylcholine, benoxylphosphatidyl choline, arachididoylphosphatidylcholine and combinations thereof.

17. The method as described in any of the Claims 12 through 16, further characterized in that said suspension means and said perforated microstructures have a refractive index differential of approximately less than 0.5.

18. The method as described in any of the Claims 12 to 17, further characterized in that said perforated microstructures comprise hollow, porous microspheres.

19. The method as described in any of the Claims 12 to 18, further characterized in that the average aerodynamic diameter of said perforated microstructures is between 0.5 and 5 μm.

20. The method as described in any of the Claims 12 to 19, further characterized in that said bioactive agent is selected from the group consisting of anti-allergens, bronchodilators, lung surfactants, analgesics, antibiotics, leukotriene inhibitors or antagonists, antistamines, anti-inflammatories, antineoplastic, anticholinergic, anesthetic, anti -Tuberculosis, imaging agents, cardiovascular agents, enzymes, steroids, genetic material, viral vectors, anti-perception agents, proteins, peptides and combinations thereof.

21. A method for stabilizing a respiratory dispersion, reducing attractive forces, comprising the steps of: providing a plurality of peforated microstructures; combination of the perforated microstructures with a suspension medium comprising at least one fluorochemical, wherein the suspension medium and the perforated microstructures are selected to provide a differential value of the refractive index, less than about

0. 5

22. The method as described in Claim 21, further characterized in that said perforated microstructures comprise a surfactant.

23. The method as described in Claim 21, further characterized in that said surfactant is selected from the group consisting of phospholipids, non-ionic detergents, non-ionic block copolymers, ionic surfactants, biocompatible fluorinated surfactants, and combinations thereof.

24. The method as described in Claim 22 or 23, further characterized in that said surfactant is a phospholipid.

25. The method as described in Claim 24, further characterized in that said phospholipid is selected from the group consisting of dilauroylphosphatidylcholine, dioleylphosphatidylcholine, dipalmitoylphosphatidylcholine, disteroylphosphatidylcholine, benoxylphosphatidyl choline, arachididoylphosphatidylcholine and combinations thereof.

26. The method as described in any of the Claims 21 to 25, further characterized in that said perforated microstructures contain hollow, porous microspheres.

27. The method as described in any of the Claims 21 to 26, further characterized in that said bioactive agent is selected from the group consisting of anti-allergens, bronchodilators, lung surfactants, analgesics, antibiotics, leukotriene inhibitors or antagonists, antistamines, anti-inflammatories, antineoplastic, anticholinergic, anesthetics, anti -Tuberculosis, imaging agents, cardiovascular agents, enzymes, steroids, genetic material, viral vectors, anti-perception agents, proteins, peptides and combinations thereof.

28. A stable respiratory dispersion for use in a nebulizer comprising a suspension medium, having dispersed therein, a plurality of perforated microstructures, comprising at least one bioactive agent wherein said suspension medium penetrates substantially said perforated microstructures.

29. The dispersion as described in Claim 28, further characterized in that said perforated microstructures comprise a surfactant.

30. The dispersion as described in Claim 29, further characterized in that said surfactant is selected from the group consisting of phospholipids, non-ionic detergents, non-ionic block copolymers, ionic surfactants, biocompatible fluorinated surfactants and combinations thereof.

31. The dispersion as described in Claim 29 or 30, further characterized in that said surfactant is a phospholipid.

32. The dispersion as described in Claim 31, further characterized in that said phospholipid is selected from the group consisting of dilauroylphosphatidylcholine, dioleylphosphatidylcholine, dipalmitoylphosphatidylcholine, disteroylphosphatidylcholine, benoxylphosphatidyl choline, arachididoylphosphatidylcholine and combinations thereof.

33. The dispersion as described in any of Claims 28 to 32, further characterized in that said suspension means and said perforated microstructures have a refractive index differential of approximately less than 0.4.

34. The dispersion as described in any of Claims 28 to 33, further characterized in that said perforated microstructures comprise hollow, porous microspheres.

35. The dispersion as described in any of the Claims 28 to 34, further characterized in that the average aerodynamic diameter of said perforated microstructures is between 0.5 and 5 μm.

36. The method and as described in any of the Claims 28 through 35, further characterized in that the bioactive agent is selected from the group consisting of anti-allergens, bronchodilators, lung surfactants, analgesics, antibiotics, leukotriene inhibitors or antagonists, antistamines, anti-inflammatories, antineoplastic, anticholinergic, anesthetic, anti -Tuberculosis, imaging agents, cardiovascular agents, enzymes, steroids, genetic material, viral vectors, anti-perception agents, proteins, peptides and combinations thereof.

37. An inaction system for the pulmonary administration to a patient of a bioactive agent, which comprises: a container for fluids; a stable respiratory dispersion in said fluid container, wherein said stabilized dispersion comprises a continuous phase of fluorochemicals and at least one bioactive agent; and a nebulizer operably associated with said fluid container, wherein the nebulizer has the ability to aerosolize and discharge stable respiratory dispersion.

38. The system as described in Claim 37, further characterized in that said stabilized dispersion comprises an inverse emulsion, a microemulsion or a particulate dispersion.

39. The system as described in Claim 37, further characterized in that said stabilized dispersion comprises a plurality of suspended particulates in said continuous fluorochemical phase, wherein said particulates are selected from the group consisting of micronized particles, nanocrystals, spray-dried microspheres. , microstructures and combinations thereof.

40. The system as described in Claim 37, further characterized in that said stabilized dispersion comprises a plurality of microstructures suspended in said fluorochemical continuous phase.

41. The system as described in Claim 40, further characterized in that said perforated microstructures comprise a surfactant.

42. The system as described in Claim 37, further characterized in that said surfactant is selected from the group consisting of phospholipids, nonionic detergents, nonionic copolymers, ionic surfactants, biocompatible fluorinated surfactants and combinations thereof.

43. The system as described in Claims 41 or 42, further characterized in that said surfactant is a phospholipid.

44. The system as described in Claim 43, further characterized in that said phospholipid is selected from the group consisting of dilauroylphosphatidylcholine, dioleylphosphatidylcholine, dipalmitoylphosphatidylcholine, disteroylphosphatidylcholine, benoxylphosphatidyl choline, arachididoylphosphatidylcholine and combinations thereof.

45. The system as described in any of Claims 40 to 44, further characterized in that the average aerodynamic diameter of the perforated microstructures is between 0.5 and 5 μm.

46. The system as described in any of Claims 37 to 45, further characterized in that said bioactive agent is selected from the group consisting of anti-allergens, bronchodilators, lung surfactants, analgesics, antibiotics, inhibitors or antagonists of leukotriene, antistamines, anti-inflammatories, antineoplastic, anticholinergic, anesthetic, anti-tuberculous agents, imaging agents, cardiovascular agents, enzymes, steroids, genetic material, viral vectors, anti-perception agents, proteins, peptides and combinations thereof.

47. The system as described in any of the Claims 37 to 46, further characterized in that said bioactive agent comprises a compound selected from the group consisting of proteins, peptides and genetic material.

48. The system as described in any of the Claims 37 through 47, further characterized in that said fluid container is a multiple dose container or a single dose container.

49. The system as described in any of Claims 37 to 48, further characterized in that said nebulizer is a jet nebulizer, an ultrasonic nebulizer or a simple bolus nebulizer.

50. A method for the pulmonary administration of one or more bioactive agents, comprising the steps of: providing a stabilized respiratory dispersion comprising one or more bioactive agents wherein the respiratory dispersion comprises a continuous fluorochemical phase; nebulizing said respiratory dispersion with a nebulizer to provide an aerosolized medicament; and administering a therapeutically effective amount of said aerosolized medicament, to at least a portion of the pulmonary air passages of a patient in need thereof. R E S U M E N R E S U M E N The stabilized dispersions are provided for the administration of a bioactive agent to the respiratory system of a patient. The dispersions preferably comprise a stabilized colloidal system, which may comprise a fluorochemical component. In the particularly preferred embodiments, the stabilized dispersions comprise perforated microstructures dispersed in a fluorochemical suspension medium. Because the density variations between the suspended particles and the suspension medium are minimized and the attractive forces between the microstructures are attenuated, the described dispersions are particularly resistant to degradation such as settling or flocculation. In the particularly preferred embodiments, the stabilized dispersions can be administered to the lung of a patient, using a nebulizer.