Rapamycin powder for pulmonary administration

Description

RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 62 / 076,651, filed on November 7, 2014.BACKGROUND OF THE INVENTION

[0002] Rapamycin (also known as sirolimus), is a macrocyclic lactone produced by Streptomyces hygroscopicus. The structural formula of rapamycin is shown below:

[0003] Rapamycin is known for its use as a therapeutic for immunosuppression and for treating transplantation rejection, host vs. graft disease, autoimmune diseases, and diseases of inflammation, solid tumors, fungal infections, adult T-cell leukemia / lymphomas and hyperproliferative vascular disorders. Rapamycin is also useful in the treatment of Lymphangioleiomyomatosis (LAM). LAM is a rare lung disease found primarily in women that often affects other organs including lymph nodes and kidneys.

[0004] Rapamycin is available in the form of crystalline powder and is known to be insoluble in water. It is known to a skilled person that the transformation of the crystalline form of a low solubility drug to the amorphous form can significantly increase the solubility thereof, which is also true for rapamycin. However amorphous rapamycin is extremely chemically unstable and is therefore not easily formulated into any pharmaceutical dosage form. The present invention overcomes the problems described above by providing stable spray-dried, particle formulations of rapamycin for pulmonary administration to a patient.

[0005] Gupta et al., Mol. Pharmaceutics 2014; 11(4):1201-1207 discloses inhalable particles containing rapamycin which are prepared by spray-drying.SUMMARY OF THE INVENTION

[0006] The invention provides stable, spray-dried, particle formulations containing rapamycin, or pharmaceutically acceptable salts of rapamycin, which are useful for pulmonary administration to the respiratory tract for inducing immunosuppression and for treating transplantation rejection, host vs. graft disease, autoimmune diseases, diseases of inflammation, solid tumors, fungal infections, adult T-cell leukemia / lymphomas, hyperproliferative vascular disorders and LAM.

[0007] In a first aspect, the present invention provides a pharmaceutical composition for pulmonary delivery to the respiratory tract of a patient comprising spray-dried particles which comprise rapamycin in crystalline form and a pharmaceutically acceptable excipient, wherein the pharmaceutically acceptable excipient comprises a phospholipid, a salt and one or more of an amino acid and a sugar, and wherein the salt is selected from sodium chloride, sodium citrate, sodium lactate and potassium chloride, and the phospholipid is DPPC, and wherein the spray-dried particles have a tap density of less than 0.075 g / cm 3< .

[0008] In a second aspect, the present invention provides the pharmaceutical composition of the first aspect for use in a method of delivering rapamycin to the pulmonary system of a patient, the method comprising the steps of: a) providing a spray-dried particle formulation of the first aspect in a compartment and an inhaler to a patient wherein said powder comprises particles of rapamycin; b) dispersing the powder by breath actuation of the patient; and c) delivering the particles to the patient's respiratory system; wherein the rapamycin is delivered to the pulmonary system of the patient to treat transplantation rejection, host vs graft disease, an autoimmune disease, a disease of inflammation, a solid tumor, a fungal infection, an adult T-cell leukemia / lymphoma, a hyperproliferative vascular disorder or Lymphangioleiomyomatosis (LAM).

[0009] Preferred features of the invention are set out in the dependent claims herein.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 shows the X-ray diffraction patterns of various lots of rapamycin spray-dried powders. FIG. 1C does not form part of the invention. FIG. 2 shows the X-ray diffraction patterns of various lots of rapamycin spray-dried superimposed over one another. DETAILED DESCRIPTION OF THE INVENTION

[0011] Disclosed herein is a stable, pharmaceutical composition of rapamycin formulated for pulmonary delivery comprising spray-dried particles (also referred to herein as "powders" or "dry powders") comprising rapamycin, wherein rapamycin is present in the particles in amorphous form, crystalline form, or in a combination of both amorphous and crystalline forms.

[0012] In one aspect of the invention, the tap density is from about 0.02 to 0.075 g / cm 3< . In another aspect of the invention, the tap density is from about 0.02 to 0.05 g / cm 3< . In a further aspect of the invention, the tap density is from about 0.03 to 0.06 g / cm 3< . In one aspect of the invention, the tap density is from about 0.03 to 0.04 g / cm 3< . In another aspect of the invention the median geometric size is about 5µm to 30µm, 5µm to 10µm, 7µm to 15 µm, or 7µm to 12µm.

[0013] Disclosed herein is a pharmaceutical composition for pulmonary delivery comprising particles containing a pharmaceutical agent and having a median geometric size of greater than about 5 microns (µm) and a tap density of less than about 0.075 g / cm 3< .

[0014] Disclosed herein is a method of delivering rapamycin to the pulmonary system of a patient comprising the steps of: providing a spray-dried particle formulation of rapamycin in a compartment and an inhaler to a patient wherein said powder comprises particles of rapamycin; dispersing the powder by breath actuation of the patient; and delivering the particles to the patient's respiratory system.

[0015] In one aspect of this invention, an inhaler is a dry powder inhaler. A variety of inhalers can be used including the Aerolizer, Diskus, Flexhaler, Handihaler, Neohaler, Pressair, Rotahaler, Turbohaler, and Twisthaler. Other dry powder inhalers which can be used are described in US patent 6,766,799, US patent 7,278,425 and US patent 8,496,002. In one aspect of the invention, the compartment is a capsule or a blister pack. In one aspect of the invention, the inhaler has a resistance of about 0.05 to about 0.25, about 0.15 to about 0.25, 0.05 to about 0.15, 0.2 to about 0.25, or about 0.2. Resistance as referred herein is measured in: Square root of Cm H2O / Liters per minute.

[0016] In another aspect of the invention, the rapamycin powder in said compartment has a median geometric diameter of greater than about 5µm, of about 5µm to about 30µm, of about 5µm to about 15µm, or of about 7µm to about 12µm. In one specific embodiment, the particles in said compartment have a median geometric diameter of 10-12µm and the particles delivered to the patient's respiratory tract have a median geometric diameter of 8-9µm. In another embodiment, the particles delivered to the patient's respiratory tract have a 5 to 20% smaller, 5 to 10% smaller, or 8 to 15% smaller median geometric diameter than the particles in said compartment.

[0017] Disclosed herein is a pharmaceutical composition for pulmonary delivery comprising particles of rapamycin having a geometric size of greater than about 5µm and a tap density of less than about 0.075 g / cm 3< .

[0018] The particles may comprise rapamycin, a phospholipid and a salt. The particles may comprise rapamycin, a phospholipid, a salt, an optional amino acid, and an optional sugar.

[0019] The salts used in the compositions of the inventionare sodium chloride (NaCl), sodium citrate, sodium lactate, and potassium chloride. The salt may be sodium chloride. The phospholipid used in the compositions of the invention is dipalmitoylphosphatidylcholine (DPPC). Other phospholipids include dilauroylphosphatidylcholine (DLPC), and disaturated-phosphatidylcholine (DSPC). Examples of amino acids suitable for use in the compositions of the invention include, but are not limited to, hydrophobic amino acids such as leucine, isoleucine, alanine, valine phenylalanine and glycine. Examples of sugars suitable for use in the compositions of the invention include, but are not limited to, lactose and maltodextrin.

[0020] In one embodiment of the invention, the pharmaceutical composition contains a powder comprising 5 to 50% rapamycin, 5-20% phospholipid, and 1-10% sodium chloride as measured by percent of dry solids in the powder. In one embodiment, the pharmaceutical compositions have the formulations shown in Table 1 (10:58:30:2 Rapamycin:Maltodextrin:L-Leu:NaCl is not within the scope of the invention). Rapamycin Formulations30:60:8:2 Rapamycin:Maltodextrin:DPPC:NaCl10:58:30:2 Rapamycin:Maltodextrin:L-Leu:NaCl5:55:30:8:2 Rapamycin:Maltodextrin:L-Leu:DPPC:NaCl10:50:30:8:2 Rapamycin:Lactose:L-Leu:DPPC:NaCitrate40:40:18:2 Rapamycin:Lactose:DPPC:NaCitrate5:75:18:2 Rapamycin:L-Leu:DPPC:NaCitrate25:65:8:2 Rapamycin:L-Leu:DPPC:NaCl

[0021] Particles of the invention may have an external surface area of greater than 10m 2< / g. In another embodiment, the external surface area is greater than 15m 2< / g, greater than 20m 2< / g or about 10 to about 50 m 2< / g.

[0022] Gravimetric analysis, using Cascade impactors, is a method of measuring the size distribution of airborne particles. The Andersen Cascade Impactor (ACI) is an eight-stage impactor that can separate aerosols into nine distinct fractions based on aerodynamic size. The size cutoffs of each stage are dependent upon the flow rate at which the ACI is operated. Preferably the ACI is calibrated at 60 L / min. A two-stage collapsed ACI may be used for particle optimization. The two-stage collapsed ACI consists of stages 0, 2 and F of the eight-stage ACI and allows for the collection of two separate powder fractions. At each stage an aerosol stream passes through the nozzles and impinges upon the surface. Particles in the aerosol stream with a large enough inertia will impact upon the plate. Smaller particles that do not have enough inertia to impact on the plate will remain in the aerosol stream and be carried to the next stage.

[0023] The ACI is calibrated so that the fraction of powder that is collected on a first stage is referred to herein as "fine particle fraction" or "FPF". The FPF corresponds to the percentage of particles that have an aerodynamic diameter of less than 5.6µm. The fraction of powder that passed the first stage of the ACI and is deposited on the collection filter is referred to as "FPF(3.4)". This corresponds to the percentage of particles having an aerodynamic diameter of less than 3.4µm.

[0024] The FPF fraction has been demonstrated to correlate to the fraction of the powder that is deposited in the lungs of the patient, while the FPF(3.4) has been demonstrated to correlate to the fraction of the powder that reaches the deep lung of a patient. In accordance with the invention, the FPF of the inhalable powder of the nominal dose contained in the capsule (i.e., the percentage of particles in the powder contained in the capsule that have an aerodynamic diameter of less than 5.6µm) may be about 40% or more. The FPF of the nominal dose of the inhalable powder contained in the capsule may be about 50%, 60%, or 70%, or 80%, or 90%. The FPF may be about 50% to about 60% of the nominal dose of the inhalable powder contained in the inhaler. The FPF may be about 55% to about 65% of the nominal dose of the inhalable powder contained in the inhaler. The FPF may be about 50% to about 70% of the nominal dose of the inhalable powder contained in the inhaler. The FPF may be about 57% to about 62% of the nominal dose of the inhalable powder contained in the inhaler. The FPF may be about 50% to about 69% of the nominal dose of the inhalable powder contained in the inhaler. The FPF may be about 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, or 65% of the nominal dose of the inhalable powder contained in the inhaler.

[0025] As used herein, the term "nominal powder dose" is the total amount of powder held in the capsule. As used herein, the term "nominal drug dose" is the total amount of Rapamycin contained in the nominal powder dose. The nominal powder dose is related to the nominal drug dose by the load percent of drug in the powder.

[0026] The nominal powder dose may be 25-50mg by dry weight. The nominal powder dose may be 25-40mg by dry weight. The nominal powder dose may be 30-35mg by dry weight or 32-38mg by dry weight.

[0027] Another method for measuring the size distribution of airborne particles is the Multi-stage liquid Impinger (MSLI). The Multi-stage liquid Impinger (MSLI) operates on the same principles as the Anderson Cascade Impactor (ACI), but instead of eight stages there are five in the MSLI. Additionally, instead of each stage consisting of a solid plate, each MSLI stage consists of an methanol-wetted glass frit. The wetted stage is used to prevent bouncing and re-entrainment, which can occur using the ACI. The MSLI is used to provide an indication of the flow rate dependence of the powder. This can be accomplished by operating the MSLI at 30, 60, and 90 L / min and measuring the fraction of the powder collected on stage 1 and the collection filter. If the fractions on each stage remain relatively constant across the different flow rates then the powder is considered to be approaching flow rate independence.

[0028] In the present invention, the spray-dried particles have a tap density of less than about 0.075 g / cm 3< . For example, the particles have a tap density between 0.02 and 0.075 g / cm 3< , between 0.02 and 0.05 g / cm 3< , between 0.03 and 0.06 g / cm 3< , between 0.03 and 0.04 g / cm 3< , or less than about 0.05 g / cm 3< , or a tap density less than about 0.04 g / cm 3< , a tap density less than about 0.03 g / cm 3< . Tap density can be measured by using instruments known to those skilled in the art such as the Dual Platform Microprocessor Controlled Tap Density Tester (Vankel, N.C.) or a GEOPYC ™< instrument (Micrometrics Instrument Corp., Norcross, GA, 30093). Tap density is a standard measure of the envelope mass density. Tap density can be determined using the method of USP Bulk Density and Tapped Density, United States Pharmacopia convention, Rockville, Md., 10th Supplement, 4950-4951, 1999. Features which can contribute to low tap density include irregular surface texture and porous structure. The envelope mass density of an isotropic particle is defined as the mass of the particle divided by the minimum sphere envelope volume within which it can be enclosed. The particles may have an envelope mass density of less than about 0.4 g / cm 3< .

[0029] The inhalable powder of the invention has a preferred particle size, e.g., a volume median geometric diameter (VMGD) of at least about 1 micron (µm). The VMGD may be greater than 5µm. The VMGD may be between about 5µm and 30µm, between about 5µm and 10µm, between about 7µm and 15µm and between about 7µm and 12µm. The diameter of the spray-dried particles, for example, the VMGD, can be measured using a laser diffraction instrument (for example Helos, manufactured by Sympatec, Princeton, N.J.). Other instruments for measuring particle diameter are well known in the art. The diameter of particles in a sample will range depending upon factors such as particle composition and methods of synthesis. The distribution of size of particles in a sample can be selected to permit optimal deposition to targeted sites within the respiratory tract.

[0030] The particles of the inhalable powder of the invention preferably have a "mass median aerodynamic diameter" (MMAD), also referred to herein as "aerodynamic diameter", between about 1µm and about 5µm or any subrange encompassed between about 1µm and about 5µm. For example, but not limited to, the MMAD is between about 1µm and about 3µm, or the MMAD is between about 3µm and about 5µm. In one embodiment, the MMAD is between 1.5µm and 2.5µm. Experimentally, aerodynamic diameter can be determined by employing a gravitational settling method, whereby the time for an ensemble of powder particles to settle a certain distance is used to infer directly the aerodynamic diameter of the particles. An indirect method for measuring the mass median aerodynamic diameter (MMAD) is the multi-stage liquid impinger (MSLI). The aerodynamic diameter, d aer , can be calculated from the equation: d aer = d g √ ρ tap where d g is the geometric diameter, for example the MMGD, and ρ is the powder density.

[0031] Powders for use in capsules of this invention are produced by spray drying. In some cases, spray-drying can produce extremely dry particles which may have poor handling properties and may be difficult to compact into a capsule in a dense manner. A nitrogen source with a specified moisture level may be flown over, across, or through the dry powder to add a specific moisture content to the dry powder. Such moisture can provide the desired working density of the powder. Spray drying methods in accordance with the invention are described in the Examples herein and in U.S. Patent Numbers: 6,848,197 and 8,197,845.

[0032] The inhalable powder comprising rapamycin as described above is used to fill capsules suitable for use in an inhaler. The term "capsule material" as used herein refers to the material from which the shell of the capsule for inhalation is made. The capsule material according to the invention may be selected from among gelatin, cellulose derivatives, starch, starch derivatives, chitosan and synthetic plastics.

[0033] If gelatin is used as the capsule material, examples according to the invention may be selected from among polyethyleneglycol (PEG), PEG 3350, glycerol, sorbitol, propyleneglycol, PEO-PPO block copolymers and other polyalcohols and polyethers. If cellulose derivatives are used as the capsule material, examples according to the invention may be selected from hydroxypropylmethylcellulose (HPMC), hydroxypropylcellulose, methylcellulose, hydroxymethylcellulose and hydroxyethylcellulose. If synthetic plastics are used as the capsule material, examples according to the invention may be selected from polyethylene, polycarbonate, polyester, polypropylene and polyethylene terephthalate. The capsule material may further comprise titanium dioxide. The capsule preferably comprises HPMC and titanium dioxide. The capsule may comprise carrageenan. The capsule may comprise potassium chloride. The capsule may comprise HPMC, carrageenan, potassium chloride, and titanium dioxide. The capsule size may be selected from 000, 00, 0, 1, or 2, preferably the capsule size is 00.

[0034] The capsule may be a hydroxypropylmethylcellulose (HPMC) capsule. The capsule may be is a hydroxypropylmethylcellulose size 00 capsule. The capsule material may comprise HPMC and titanium dioxide and the capsule size may be 00.

[0035] A 00 capsule may contain between 15 and 50 grams of rapamycin by dry weight. A 00 capsule may contain between 20 and 40 grams of rapamycin by dry weight. A 00 capsule may contain between 25 and 35 grams of rapamycin by dry weight. A 00 capsule may contain about 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40 grams of rapamycin by dry weight.

[0036] The powders may have low electrostatic charge to enable high dispersion from the capsule.

[0037] The capsules disclosed herein are particularly suitable for use in a dry powder inhaler for the delivery of a dry powder composition comprising an effective amount of rapamycin to a patient in need thereof for example, for treating transplantation rejection, host vs. graft disease, autoimmune diseases, diseases of inflammation, solid tumors, fungal infections, adult T-cell leukemia / lymphomas and hyperproliferative vascular disorders and LAM.

[0038] As used herein, the term "effective amount" means the amount needed to achieve the desired effect or efficacy. The actual effective amounts of drug can vary according to the specific drug or combination thereof being utilized, the particular composition formulated, the mode of administration, and the age, weight, condition of the patient, and severity of the episode being treated.

[0039] The present invention will be further understood by reference to the following non-limiting examples. Lot 106187 of Example 1 does not form part of the invention.EXAMPLES Example 11. Formulating spray solutions

[0040] Rapamycin and DPPC are allowed to equilibrate to room temperature for at least 30 minutes before weighing. Required amounts of water and ethanol are weighed and transferred to the aqueous and organic phase feed vessels respectively, and the stirring element in both vessels is turned on. The required amounts of Lactose, L-Leucine, Maltodextrin, Sodium chloride, and sodium citrate are weighed individually (wherever required) and added to the aqueous phase vessel and allowed to dissolve without allowing vortex formation. The required amount of DPPC (wherever required), and Rapamycin are weighed and added to the organic phase vessel and allowed to dissolve.2. Spray drying initiationa. Formulations containing Maltodextrin

[0041] Spray drying is initiated by starting the drying gas flow (set to 100 kg / hr). The drying gas inlet temperature is set to 130 C. After the spray dryer outlet temperature reaches 80 C°, the liquid skid inlet is set to allow blank solvents (aqueous flow = 28 mL / min and organic flow = 42 mL / min) to be atomized with the aid of nitrogen (atomizing gas flow = 20 g / min) into the spray dryer and the system is allowed to cool and stabilize to an outlet temperature of 55 C°.b. Formulations not containing Maltodextrin

[0042] Spray drying is initiated by starting the drying gas flow (set to 100 kg / hr). The drying gas inlet temperature is set to 110 C°. After the spray dryer outlet temperature reaches 80 C°, the liquid skid inlet is set to allow blank solvents (aqueous flow = 10 mL / min and organic flow = 60 mL / min) to be atomized with the aid of nitrogen (atomizing gas flow = 20 g / min) into the spray dryer and the system is allowed to cool and stabilize to an outlet temperature of 55 C°.3. Spray drying continuation for both types of formulations

[0043] Product filter pulsing is initiated and product filter purge flow is set to 15 scfh. After the system stabilizes at 55 C°, the liquid skid inlet is switched to the feed solvents prepared above and the process is continued till the feed solvents run out. At the point when feed solvents run out, the liquid skid inlet is switched back to blank solvents which are allowed to spray for about 10 minutes. At this point, powder collected at the bottom of the product filter is transferred to its final collection vessel in a glove box maintained at an RH of 15%. After spraying the blank solvent for 10 minutes, the system is shut down by shutting down the liquid lines, atomization gas, drying gas heater, drying gas inlet and finally the exhaust.4. Summary of process parameters

[0044] Process Parameters Maltodextrin formulations non- Maltodextrin formulations Inlet Temperature (°C)130.0110.0Outlet Temperature (°C)55.055.0Drying Gas Rate (kg / hr)100.0100.0Chamber Pressure ("wc)-2.0-2.0Atomization Gas Flow Rate (g / min)20.020.0Aqueous Flow (mL / min)28.010.0Organic flow (mL / min)42.060.0Product Filter Purge Rate (scfh)15.015.0 5. Results

[0045] The spray-dried formulations and their particle characteristics are shown in Table 2. The X-ray powder diffractions of the various lots are shown in FIG. 1. The same patterns as shown in FIG. 1 are superimposed on one another in FIG. 2. Table 2Lot Description gPSD, D50 (um) FPF, <5.6 um (%) ρBulk (g / cc) ρTap (g / cc) 10618630:60:8:2 Rapamycin:Maltodextrin:DPPC:NaCl9.2540.030.0510618710:58:30:2 Rapamycin:Maltodextrin:L-Leu:NaCl4.8470.060.101061885:55:30:8:2 Rapamycin:Maltodextrin:L-Leu:DPPC:NaCl16.2560.020.0410618910:50:30:8:2 Rapamycin:Lactose:L-Leu:DPPC:NaCitrate6.6520.050.0910619040:40:18:2 Rapamycin:Lactose:DPPC:NaCitrate8.8340.050.091061915:75:18:2 Rapamycin:L-Leu:DPPC:NaCitrate6.1510.080.1210612925:65:8:2 Rapamycin:L-Leu:DPPC:NaCl4.2440.090.19

[0046] While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims. It should also be understood that the embodiments described herein are not mutually exclusive and that features from the various embodiments may be combined in whole or in part in accordance with the invention.

Claims

1. A pharmaceutical composition for pulmonary delivery to the respiratory tract of a patient comprising spray-dried particles which comprise rapamycin in crystalline form and a pharmaceutically acceptable excipient, wherein the pharmaceutically acceptable excipient comprises a phospholipid, a salt and one or more of an amino acid and a sugar, and wherein the salt is selected from sodium chloride, sodium citrate, sodium lactate and potassium chloride, and the phospholipid is DPPC, and wherein the spray-dried particles have a tap density of less than 0.075 g / cm3.

2. The pharmaceutical composition of claim 1, wherein the salt is sodium chloride.

3. The pharmaceutical composition of claim 2, wherein the spray-dried particles comprise 5 to 50% rapamycin, 5 to 20% phospholipid and 1 to 10% sodium chloride, as measured by percent of dry solids in the powder.

4. The pharmaceutical composition of claim 1, for use in a method of delivering rapamycin to the pulmonary system of a patient, the method comprising the steps of: a) providing a spray-dried particle formulation of claim 1 in a compartment and an inhaler to a patient wherein said powder comprises particles of rapamycin; b) dispersing the powder by breath actuation of the patient; and c) delivering the particles to the patient's respiratory system; wherein the rapamycin is delivered to the pulmonary system of the patient to treat transplantation rejection, host vs graft disease, an autoimmune disease, a disease of inflammation, a solid tumor, a fungal infection, an adult T-cell leukemia / lymphoma, a hyperproliferative vascular disorder or Lymphangioleiomyomatosis (LAM).