PARTICULATE COMPOSITIONS FOR DELIVERY OF POORLY SOLUBLE DRUGS

Description

FIELD OF THE INVENTION

[0001] The present invention relates generally to compositions comprising particles of buprenorphine or buprenorphine HCl encapsulated by PEG, and to pharmaceutical compositions comprising such encapsulated compositions. The encapsulated particle compositions described herein allow buprenorphine or buprenorphine HCl to be administered with good bioavailability by routes that are non-invasive to patients, such as by oral administration.

BACKGROUND

[0002] Oral administration of drugs is generally preferred for reasons of patient comfort and compliance. However, many drugs, including many opioids, are poorly soluble at neutral pH, and are thus poorly or variably absorbed when delivered orally. Consequently, many such drugs are administered through more invasive routes, such as by sublingual, buccal, subcutaneous, or intravenous routes.

[0003] Several approaches for improving the oral delivery of poorly soluble drugs have demonstrated some promise. For example, poorly soluble drugs have been administered as dispersions in large amounts of fatty acids, and have been wet-milled to yield nanoparticles. Leuner & Dressman (Eur. J Pharmaceutics & Biopharmaceutics 50, (2000), 47-60) describe approaches for improving the solubility of poorly water soluble compounds for oral delivery using solid dispersions. Such approaches include using water soluble polymers such as PEG, PVP and/or PVA, cellulose derivatives, polyacrylates and polymethacrylates. However, each of those approaches suffers from certain drawbacks, such as, e.g., inadequate stability, difficulty of manufacture, adverse interactions with the drug to be delivered, or the use of toxic amounts of adjuvants or inhibitors. Thus, there remains a need for compositions and methods for the non-invasive delivery of poorly soluble drugs.

SUMMARY

[0004] The invention provides a composition comprising particles having an average diameter of less than 2 mm, wherein the particles comprise buprenorphine or buprenorphine HCl present in an amount ranging from about 0.2% to about 4% by mass of the particles, and polyethylene glycol (PEG), wherein the buprenorphine or buprenorphine HCl is encapsulated by the PEG.

[0005] In some other embodiments, the composition further comprises a surfactant, such as, e.g., a polysorbate surfactant.

[0006] In other embodiments, the invention provides pharmaceutical compositions comprising such encapsulated compositions. Such pharmaceutical compositions may, in some embodiments, further comprise at least one excipient. In other embodiments, such pharmaceutical compositions may further comprise a second compound such as, e.g., a second drug, including, e.g., an opioid receptor antagonist, an anti-inflammatory drug, or an analgesic. For example, in some embodiments, the invention provides a pharmaceutical composition comprising a composition comprising the PEG-encapsulated buprenorphine composition described above. In certain embodiments, the pharmaceutical composition further comprises naloxone.

[0007] Described herein is a first method of making a composition comprising particles of a poorly soluble drug encapsulated by a stabilizer, the method comprising:

blending a poorly soluble drug together with a stabilizer to form a mixture;

processing said mixture to form coarse particles having an average diameter ranging from about 0.1 mm to about 5 mm; and

processing said coarse particles to form fine particles having an average diameter ranging from about 0.1 mm to about 3 mm.

[0008] Also described herein is a second method of making a composition comprising particles of a poorly soluble drug encapsulated by a stabilizer, the method comprising:

blending a poorly soluble drug together with a stabilizer to form a mixture;

heating said mixture to a temperature sufficient for extrusion of the mixture;

extruding said mixture to form coarse particles having an average diameter ranging from about 0.1 mm to about 5 mm;

cooling said coarse particles; and

processing said coarse particles to form fine particles having an average diameter ranging from about 0.1 mm to about 3 mm.

[0009] Also described herein is a method of making a pharmaceutical composition, comprising the first or second method described above, and further comprising:

formulating the fine particles.

[0010] Also described herein is a method of making a pharmaceutical composition, comprising the first or second method described above, and further comprising:

mixing the fine particles with at least one excipient to form a second mixture; and

formulating the second mixture.

[0011] In yet other embodiments, the invention provides the composition of the invention for use in treating pain.

[0012] In other embodiments, the invention provides the composition of the invention for use in treating opiate addiction.

DETAILED DESCRIPTION

I. PARTICULATE DELIVERY SYSTEMS

[0013] The composition of the invention comprises particles having an average diameter of less than 2 mm, wherein the particles comprise buprenorphine or buprenorphine HCl present in an amount ranging from about 0.2% to about 4% by mass of the particles, and polyethylene glycol (PEG), wherein the buprenorphine or buprenorphine HCl is encapsulated by the PEG.

[0014] In some embodiments, the invention provides a composition (also referred to as a particulate delivery system or PDS) comprising particles of about 0.2% to about 4% buprenorphine or buprenorphine HCl encapsulated by PEG, wherein those particles are fine particles, and have a diameter of less than 2 mm, less than 600 µm, less than 500 µm, or less than 300 µm. For example, the particles may have a diameter of less than 1.68 mm (corresponding to a 12 mesh sieve), less than 1.40 mm (corresponding to a 14 mesh sieve), less than 1.20 mm (corresponding to a 16 mesh sieve), less than 1.00 mm (corresponding to an 18 mesh sieve), less than 0.853 mm (corresponding to a 20 mesh sieve), less than 0.710 mm (corresponding to a 25 mesh sieve), less than 0.599 mm (corresponding to a 30 mesh sieve), or less than 0.500 mm (corresponding to a 35 mesh sieve). In other embodiments, the particles may have a diameter of less than 300 µm, and may be able to pass through a 50 mesh sieve.

[0015] As used herein, the term drug encompasses the corresponding salts, hydrates, solvates, prodrugs, and complexes of the drug. Thus, the drug may be present as, e.g., a free base, a salt, a hydrate, a prodrug, a solvate (including a mixed solvate), or a complex (such as a pharmaceutically acceptable complex, and/or a complex with a polymer).

[0016] As used herein, the terms poorly soluble drug, drug having poor solubility, and the like refer to a drug (in its neutral (i.e., uncharged) state) having a water solubility at neutral pH of less than 10 mg/ml. The drug (in its neutral state) may have a water solubility at neutral pH of less than 5 mg/ml. The drug (in its neutral state) may have a water solubility at neutral pH of less than 1 mg/ml. For example, buprenorphine base (i.e., uncharged buprenorphine) has a solubility at neutral pH of <1 mg/ml (whereas the corresponding hydrochloride salt has a solubility at neutral pH of 17 mg/ml). Thus, as used herein, buprenorphine (including buprenorphine base and its salts, hydrates, solvates, complexes, etc.) is a poorly soluble drug. Similarly, morphine base (i.e., uncharged morphine) has a solubility at neutral pH of <1 mg/ml (whereas the corresponding sulfate has a solubility at neutral pH of 64 mg/ml). Thus, as used herein, morphine (including morphine base and its salts, hydrates, solvates, complexes, etc.) is a poorly soluble drug. In a third example, oxycodone base (i.e., uncharged oxycodone) has a solubility at neutral pH of <1 mg/ml (whereas the corresponding hydrochloride has a solubility at neutral pH of 100 mg/ml). Thus, as used herein, oxycodone (including oxycodone base and its salts, hydrates, solvates, complexes, etc.) is a poorly soluble drug.

[0017] As described herein, the poorly soluble drug may be chosen from opioids (including opiates). Opioids include naturally-occurring, synthetic, and semisynthetic opioids, such as, e.g., alfentanil, allylprodine, alphaprodine, anileridine, benzylmorphine, bezitramide, butorphanol, clonidine, clonitazene, codeine, cyclazocine, desomorphine, dextromoramide, dezocine, diampromide, dihydrocodeine, dihydromorphine, dimenoxadol, dimepheptanol, dimethylthiambutene, dioxaphetyl butyrate, dipipanone, eptazocine, ethoheptazine, ethyl methylthiambutene, ethylmorphine, etonitazine, fentanyl, heroin, hydrocodone, hydromorphone, hydroxypethidine, isomethadone, ketobemidone, levallorphan, levomethadyl, levorphanol, levophenacylmorphan, lofentanil, meperidine, meptazinol, metazocine, methadone, metopon, morphine, myrophine, nalbuphine, naloxone, naltrexone, narceine, nicomorphine, norlevorphanol, normethadone, nalorphine, normorphine, norpipanone, opium, oxycodone, oxymorphone, papaveretum, pentazocine, phenadoxone, phenomorphan, phenazocine, phenoperidine, piminodine, piritramide, propheptazine, promedol, properidine, propiram, propoxyphene, remifentanil, sulfentanil, tramadol, and tilidine. The poorly soluble drug of the composition of the invention is buprenorphine, or buprenorphine HCl.

[0018] In some embodiments, the PDS may further comprise an additional compound, such as an additional drug. The additional drug may be chosen from, e.g., opioid receptor antagonists (including µ-receptor antagonists), opioid receptor agonists (including µ-receptor agonists), mixed µ-agonists/µ-antagonists, anti-inflammatory drugs, and analgesics. In some embodiments, the second drug is an opioid receptor antagonist, such as, e.g., the µ-opioid receptor antagonist naloxone, including naloxone·HCl (naloxone hydrochloride). Where the poorly soluble drug is an opioid analgesic, the opioid receptor antagonist may be added to deter abuse of the opioid analgesic.

[0019] As described herein, the poorly soluble drug may be present in an amount ranging from about <1% to about 90% of the PDS by mass. For example, the poorly soluble drug may be present in an amount ranging from about 0.01% to about 90%, about 0.01% to about 10%, about 0.2 to about 5%, about <1% to about 10%, about 0.01 % to about 10%, about 0.1% to about 10%, about 0.01% to about 5%, about 0.1% to about 5%, about 0.1 % to about 3%, about <1% to about 50%, about <1% to about 30%, about <1% to about 80%, about 5% to about 90%, about 10% to about 95%, or about 0.1 to about 5% of the PDS, by mass.

[0020] As described herein, the stabilizer may be a polymer, such as, e.g., a water-soluble polymer, a polymer of neutral charge, or a water-soluble polymer of neutral charge. As described herein, the stabilizer may be biodegradable. As describeb herein, the stabilizer may be bioerodable. As described herein, the stabilizer may be considered by the FDA to be generally regarded as safe (GRAS).

[0021] As described herein, the stabilizer may be a polymer chosen from polypropylene oxide or copolymers thereof. As described herein, the stabilizer may be a water-soluble polymer of neutral charge chosen from polyvinyl alcohol, polyvinylpyrrolidone (PVP), block copolymers of ethylene oxide and propylene oxide such as, e.g., poloxamers, and tetrafunctional block copolymers derived from sequential addition of propylene oxide and ethylene oxide to ethylenediamine.

[0022] According to the composition of the invention, the stabilizer is PEG, which may have an average molecular weight of about, e.g., 500, 1000, 2000, 3000, 3350, 3500, 4000, 4500, 5000, 6000, 8000, 10,000, or 100,000 Da, or an average molecular weight ranging from, e.g., about 100 Da to about 100,000 Da, about 100 Da to about 6,000 Da, about 500 Da to about 5000 Da, about 1000 Da to about 4000 Da, about 2000 Da to about 4000 Da, about 2000 Da to about 6000 Da, about 1000 Da to about 10,000 Da, or about 3000 Da to about 4000 Da.

[0023] In exemplary embodiments, the PEG may have an average molecular weight of 3350 Daltons (i.e., PEG 3350). In other embodiments, the PEG may have an average molecular weight ranging from, e.g., about 100 Da to about 100,000 Da, about 100 Da to about 6,000 Da, about 500 Da to about 5000 Da, about 1000 Da to about 4000 Da, about 2000 Da to about 4000 Da, about 2000 Da to about 6000 Da, about 1000 Da to about 10,000 Da, or about 3000 Da to about 4000 Da.

[0024] In some embodiments, the composition further comprises at least one excipient, such as, e.g., a surfactant, surface stabilizer, or other enhancer. For example, in some embodiments, the composition further comprises at least one surfactant, which may be a nonionic surfactant such as, e.g., a polysorbate surfactant. In exemplary embodiments, the composition further comprises polysorbate 20 (Tween 20). In other embodiments, the composition further comprises an emulsifier, such as, e.g., a phospholipid, propylene glycol, polysorbate, poloxamer, glyceryl monostearate, or other pharmaceutical emulsifier.

[0025] The invention provides a composition comprising particles of buprenorphine (such as, e.g., buprenorphine HCl) encapsulated by PEG (which, in some embodiments, may have an average molecular weight ranging from about 500 Daltons to about 10,000 Daltons), wherein the buprenorphine content ranges from about 0.2% to about 4% by mass of the particles. The particles have an average diameter of less than 2 mm. In some embodiments, the composition further comprises a surfactant. In certain embodiments, the PDS comprises buprenorphine, PEG 3350, and Tween 20.

II. METHODS OF MAKING PDS

[0026] Described herein is a first method of making a composition (such as those described in Section I) comprising particles of a poorly soluble drug encapsulated by a stabilizer, the method comprising:

blending a poorly soluble drug together with a stabilizer to form a mixture;

processing (e.g., by mixing or granulating) said mixture to form coarse particles having an average diameter ranging from about 0.1 mm to about 5 mm; and

processing (e.g., by milling, grinding, or crushing) said coarse particles to form fine particles having an average diameter ranging from about 0.1 mm to about 3 mm.

[0027] In the methods described herein, the particles may have a diameter of less than 1.68 mm (corresponding to a 12 mesh sieve), less than 1.40 mm (corresponding to a 14 mesh sieve), less than 1.20 mm (corresponding to a 16 mesh sieve), less than 1.00 mm (corresponding to an 18 mesh sieve), less than 0.853 mm (corresponding to a 20 mesh sieve), less than 0.710 mm (corresponding to a 25 mesh sieve), less than 0.599 mm (corresponding to a 30 mesh sieve), or less than 0.500 mm (corresponding to a 35 mesh sieve). The particles may have a diameter of less than 300 µm, and may be able to pass through a 50 mesh sieve. The particles may have a diameter of 0.6 mm or less.

[0028] The stabilizer may be heated prior to blending with the poorly soluble drug.

[0029] Also described herein is a second method of making a composition (such as those described in Section I) comprising particles of a poorly soluble drug encapsulated by a stabilizer. The second method uses a relatively continuous manufacturing process, which may be advantageous in certain circumstances. The second method comprises:

blending a poorly soluble drug together with a stabilizer to form a mixture;

heating said mixture to a temperature sufficient for extrusion of the mixture;

extruding said mixture to form coarse particles having an average diameter ranging from about 0.1 mm to about 5 mm;

cooling said coarse particles; and

processing (e.g., by milling, grinding, or crushing) said coarse particles to form fine particles having an average diameter ranging from about 0.1 mm to about 3 mm.

[0030] In the methods described herein, the particles may have a diameter of less than 1.68 mm (corresponding to a 12 mesh sieve), less than 1.40 mm (corresponding to a 14 mesh sieve), less than 1.20 mm (corresponding to a 16 mesh sieve), less than 1.00 mm (corresponding to an 18 mesh sieve), less than 0.853 mm (corresponding to a 20 mesh sieve), less than 0.710 mm (corresponding to a 25 mesh sieve), less than 0.599 mm (corresponding to a 30 mesh sieve), or less than 0.500 mm (corresponding to a 35 mesh sieve). The particles may have a diameter of less than 300 µm, and may be able to pass through a 50 mesh sieve. The particles may have a diameter of 0.6 mm or less.

[0031] The stabilizer may be heated prior to blending with the poorly soluble drug.

III. PHARMACEUTICAL COMPOSITIONS (FINAL DOSAGE FORMS)

[0032] In some embodiments, the invention provides pharmaceutical compositions (sometimes referred to as final dosage forms or FDF) comprising the composition of the invention described in Section I above.

[0033] As described herein, a poorly soluble drug may be present in a pharmaceutical composition in an amount ranging from about <1% to about 90% by mass. For example, the poorly soluble drug may be present in an amount ranging from about 0.01% to about 90%, about 0.01% to about 10%, about 0.2 to about 5%, about <1% to about 10%, about 0.01% to about 10%, about 0.1% to about 10%, about 0.01% to about 5%, about 0.1 % to about 5%, about 0.1 % to about 3%, about <1% to about 50%, about <1% to about 30%, about <1% to about 80%, about 5% to about 90%, about 10% to about 95%, or about 0.1 to about 5% of a pharmaceutical composition by mass.

[0034] In some embodiments, the pharmaceutical compositions further comprise a second compound, such as a second drug. The second drug may be chosen from, e.g., opioid receptor antagonists (including µ-receptor antagonists), opioid receptor agonists (including µ-receptor agonists), mixed µ-agonists/µ-antagonists, anti-inflammatory drugs, and analgesics. In some embodiments, the second drug is an opioid receptor antagonist, such as, e.g., the µ-opioid receptor antagonist naloxone, including naloxone·HCl (naloxone hydrochloride). Where the poorly soluble drug is an opioid analgesic, the opioid receptor antagonist may be added to deter abuse of the opioid analgesic. The resulting compositions may have reduced potential for abuse of the opioid, relative to compositions that do not comprise an opioid receptor antagonist.

[0035] In some embodiments, the pharmaceutical compositions further comprise at least one excipient (such as, e.g., a water-soluble polymer, surfactant, and/or enhancer), such as a pharmaceutically acceptable excipient. Examples of pharmaceutically acceptable excipientsare described in Remington's Pharmaceutical Sciences by E.W. Martin, and include starch, glucose, lactose, sucrose, gelatin, malt, rice, flour, chalk, silica gel, sodium stearate, glycerol monostearate, talc, sodium chloride, dried skim milk, glycerol, propylene, glycol, water, ethanol, and the like. In some embodiments, the pharmaceutical compositions also contain pH buffering reagents, and wetting or emulsifying agents.

[0036] The pharmaceutical compositions may, in some embodiments, be formulated for oral administration, for example as tablets, capsules, or other oral dosage forms. Such oral dosage forms may be prepared by conventional means. The pharmaceutical composition can also be prepared as a liquid, for example as a syrup or a suspension. The liquid can include suspending agents (e.g., sorbitol syrup, cellulose derivatives or hydrogenated edible fats), emulsifying agents (lecithin or acacia), non-aqueous vehicles (e.g., almond oil, oily esters, ethyl alcohol, or fractionated vegetable oils), and preservatives (e.g., methyl or propyl-p-hydroxybenzoates or sorbic acid). The preparations can also include flavoring, coloring and sweetening agents. Alternatively, the composition can be presented as a dry product for constitution with water or another suitable vehicle.

[0037] For buccal and sublingual administration, the composition may take the form of tablets or lozenges according to conventional protocols.

[0038] For administration by oral inhalation, the compounds are conveniently delivered in the form of an aerosol spray from a pressurized pack or nebulizer (e.g., in PBS), with a suitable propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoromethane, carbon dioxide or other suitable gas. In the case of a pressurized aerosol the dosage unit can be determined by providing a valve to deliver a metered amount. Capsules and cartridges of, e.g., gelatin for use in an inhaler or insufflator can be formulated containing a powder mix of the compound and a suitable powder base such as lactose or starch.

[0039] The pharmaceutical composition can also be formulated for parenteral administration (including, e.g., intravenous or intramuscular administration) by bolus injection. Formulations for injection can be presented in unit dosage form, e.g., in ampoules or in multidose containers with an added preservative. The compositions can take such forms as suspensions, solutions, or emulsions in oily or aqueous vehicles, and contain formulatory agents such as suspending, stabilizing and/or dispersing agents. Alternatively, the active ingredient can be in powder form for constitution with a suitable vehicle, such as, e.g., pyrogen free water.

[0040] The pharmaceutical composition can also be formulated for rectal administration as a suppository or retention enema, e.g., containing conventional suppository bases such as PEG, cocoa butter or other glycerides.

[0041] In some embodiments, the pharmaceutical compositions described herein provide improved dissolution of the poorly soluble drug, relative to the unencapsulated poorly soluble drug, and/or to another dosage form (such as, e.g., a more invasive dosage form). For example, dissolution may be increased by, e.g., at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 50%, 60%, 70%, 80%, 90%, 93%, 95%, 96%, 97%, 98%, 99%, 100%, 110%, 120%, 130%, 140%, 150%, or 200%, or by, e.g., at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, or 1000 fold, as measured by a Vankel tablet dissolution apparatus approved by the United States Pharmacopeia.

[0042] In some embodiments, the pharmaceutical compositions described herein provide improved oral bioavailability of the poorly soluble drug, relative to the unencapsulated poorly soluble drug, and/or to another dosage form (such as, e.g., a more invasive dosage form). For example, absorption may be increased by, e.g., at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 50%, 60%, 70%, 80%, 90%, 93%, 95%, 96%, 97%, 98%, 99%, 100%, 110%, 120%, 130%, 140%, 150%, or 200%, or by, e.g., at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, or 1000 fold, as measured by, e.g., in vivo pharmacokinetic studies in a preclinical animal model or human clinical evaluation.

[0043] In some embodiments, the pharmaceutical compositions described herein are immediate-release formulations. In such embodiments, the pharmaceutical compositions provide a more rapid onset of action of the poorly soluble drug, relative to the unencapsulated poorly soluble drug, and/or to another dosage form (such as, e.g., a more invasive dosage form). For example, the onset of action may be shortened by, e.g., at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 50%, 60%, 70%, 80%, 90%, 93%, 95%, 96%, 97%, 98%, 99%, 100%, 110%, 120%, 130%, 140%, 150%, or 200%, or by, e.g., at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 100, or 1000 fold, as measured by, e.g., in vivo pharmacokinetic studies in a preclinical animal model or human clinical evaluation.

[0044] In other embodiments, the pharmaceutical compositions described herein are controlled-release formulations. In such embodiments, the pharmaceutical compositions described herein provide a more rapid onset of action of the poorly soluble drug.

[0045] In some embodiments, the pharmaceutical compositions described herein have reduced absorption variability, relative to the unencapsulated poorly soluble drug, and/or to another dosage form (such as, e.g., a more invasive dosage form).

[0046] In some embodiments, the pharmaceutical compositions described herein are associated with improved patient compliance, relative to another pharmaceutical composition comprising the same poorly soluble drug (which may be in another dosage form, such as, e.g., a more invasive dosage form).

IV. METHODS OF MAKING PHARMACEUTICAL COMPOSITIONS

[0047] Also described herein is a method of making a pharmaceutical composition, comprising the first, second, or third method described in Section II above, and further comprising:

formulating the fine particles.

[0048] The fine particles may be formulated into unit doses.

[0049] Also described herein is a method of making a pharmaceutical composition, comprising the first, second, or third method described in Section II above, and further comprising:

mixing the fine particles with at least one excipient to form a second mixture; and

formulating the second mixture.

[0050] The fine particles may be formulated into unit doses.

V. MEDICAL USES

[0051] The pharmaceutical compositions described herein are useful to treat any disease or condition for which administration of a corresponding hydrophobic drug is desirable. For example, compositions comprising opioids are useful for the treatment of pain. The terms "treat," treatment," and "treating" refer to (1) a reduction in severity or duration of a disease or condition, (2) the amelioration of one or more symptoms associated with a disease or condition without necessarily curing the disease or condition, or (3) the prevention of a disease or condition. Suitable subjects include, e.g., humans and other mammals, such as, e.g., mice, rats, dogs, and non-human primates.

[0052] In certain embodiments, the invention provides the composition of the invention for use in treating pain. Moreover, in such embodiments, the pharmaceutical composition may further comprise an opioid receptor antagonist, such as, e.g., naloxone or naltrexone, to deter abuse of the opioid analgesic.

[0053] In other embodiments, the invention provides the composition of the invention for use in treating opiate addiction.

[0054] The following examples are intended to be purely exemplary of the present invention.

Example 1: Preparation of Buprenorphine·HCI PDS

[0055] A solution of 1 kg of autoclaved polyethylene glycol (Dow, PEG 3350, NF, FCC) and polysorbate (Tween 20, FCC), at a 10:1 mass ratio, cooled to less then 60°C, is aseptically mixed with 20 g of buprenorphine·HCl (Johnson Matthey, milled USP grade) powder. The suspension (which contains 2% buprenorphine) is then blended in a paddle mixer and further agitated using low-frequency sonication (as described in U.S. Pat. Appl. Pub. No. 2005/0175707) to form buprenorphine·HCl particles encapsulated in a PEG/Tween matrix. The powder is then frozen at -20°C for at least 2 hours and then ground into a fine powder using a Retsch knife mill. Particles smaller than 600 µm are separated by sieving (30 mesh). Buprenorphine content is confirmed using an HPLC method.

Example 2: Preparation of Immediate-Release Oral Buprenorphine·HCl Capsules

[0056] An immediate-release oral dosage form (gelatin capsules) containing the buprenorphine·HCl particles prepared in Example 1, as well as natoxone·HCl as an abuse-deterrent second drug, is prepared as described below. The PDS prepared in Example 1 is dry mixed with naloxone (as natoxone·HCl dihydrate, USP) and additional PEG 3350 for bulking to achieve the correct capsule fill weight (400-500 mg) to achieve the desired dose. Clear gelatin #1 capsules are then filled with the mixture in a Fast-CAP Filling machine to yield capsules containing 2.0 ± 0.2 mg buprenorphine (with respect to the free base) and 0.5 ± 0.05 mg naloxone (with respect to the free base). The capsules thus contain buprenorphine and naloxone at a ratio of 4:1, with respect to the free bases.

Example 3: Dissolution of Immediate-Release Oral Buprenorphine·HCl Capsules

[0057] The in vivo dissolution rate of the fast-release formulation prepared in Example 2 was measured by USP Paddle Method 2 at 50 or 100 rpm in 900 ml of 0.1 N HCl acidic buffer (pH between 1.6 and 3) at 37°C. It was found that greater then 75% (by weight) of the therapeutically active agent was released after 45 minutes.

Example 4: Single-Dose Pharmacokinetic Study in Rats

[0058] The composition prepared in Example 2 (prior to loading into gelatin capsules) was administered via oral gavage once daily for 14 consecutive days to male and female F-344 rats at a low (0.03 mg/kg) or high (0.5 mg/kg) dose (n=10 each). Plasma samples collected up to 8 hours from single-dose pharmacokinetic (PK) studies in male rats (non-GLP) were compared to 14-day samples using a validated extraction and LC-MS-MS analytical method.

[0059] Values for the single-dose PK study were 0.53 and 4.07 ng/ml for male rats administered 0.03 and 0.5 mg/kg, respectively (n=3-5), observed at the first 15 minute collection time. The concentration-time profiles declined from C_max in mono- or multi-exponential relationships. AUC values for the single-dose PK study were 2.51 and 10.33 ng·hr/ml for male rats administered 0.03 and 0.5 mg/kg, respectively (n=3-5). At day 14 of the repeat dose toxicity study for rats administered 0.03 and 0.5 mg/kg, respectively (n=4 each), C_max values were 1.57 and 4.11 ng/ml for males and 1.85 and 4.12 ng/ml for females, also observed at the 30 minute collection time. C_max values were similar for males and females based on 30 minute and 8 hour time points from 14-day plasma samples analyzed. Norbuprenorphine, the main metabolite of buprenorphine, and naloxone plasma concentrations were below the limit of quantitation.

Example 5: Preparation of Pharmaceutical Compositions Comprising Oxycodone

[0060] Pharmaceutical compositions comprising oxycodone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Oxycodone content	0.1-200 mg
PEG 1500 content	100-1000 mg

Example 6: Preparation of Controlled-Release Pharmaceutical Compositions Comprising Oxycodone

[0061] Controlled-release pharmaceutical compositions comprising oxycodone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Oxycodone content	0.1-200 mg
PVP K-30 content	100-1000 mg

Example 7: Preparation of Pharmaceutical Compositions Comprising Morphine

[0062] Pharmaceutical compositions comprising morphine may be prepared according to the methods described herein. The compositions may have the following characteristics:

Morphine content	0.1-100 mg
Poloxamer 407 content	100-1000 mg

Example 8: Preparation of Controlled-Release Pharmaceutical Compositions Comprising Morphine

[0063] Controlled-release pharmaceutical compositions comprising morphine may be prepared according to the methods described herein. The compositions may have the following characteristics:

Morphine content	0.1-100 mg
PEG 8000 content	100-1000 mg

Example 9: Preparation of Pharmaceutical Compositions Comprising Hydrocodone

[0064] Pharmaceutical compositions comprising hydrocodone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Hydrocodone content	0.1-100 mg
PEG 3350 content	100-1000 mg

Example 10: Preparation of Pharmaceutical Compositions Comprising Dihydrocodone

[0065] Pharmaceutical compositions comprising dihydrocodone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Dihydrocodone content	0.1-100 mg
PEG 3350 content	100-1000 mg

Example 11: Preparation of Pharmaceutical Compositions Comprising Codeine

[0066] Pharmaceutical compositions comprising codeine may be prepared according to the methods described herein. The compositions may have the following characteristics:

Codeine content	0.1-100 mg
Poloxamer 407 content	100-1000 mg

Example 12: Preparation of Pharmaceutical Compositions Comprising Meperidine

[0067] Pharmaceutical compositions comprising meperidine may be prepared according to the methods described herein. The compositions may have the following characteristics:

Meperidine content	0.1-500 mg
PEG 3350 content	100-1000 mg

Example 13: Preparation of Pharmaceutical Compositions Comprising Propoxyphene

[0068] Pharmaceutical compositions comprising propoxyphene may be prepared according to the methods described herein. The compositions may have the following characteristics:

Propoxyphene content	0.1-500 mg
PEG 3350 content	100-1000 mg

Example 14: Preparation of Pharmaceutical Compositions Comprising Levorphanol

[0069] Pharmaceutical compositions comprising levorpanol may be prepared according to the methods described herein. The compositions may have the following characteristics:

Levorphanol content	0.1-100 mg
Poloxamer 407 content	100-1000 mg

Example 15: Preparation of Pharmaceutical Compositions Comprising Oxymorphone

[0070] Pharmaceutical compositions comprising oxymorphone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Oxymorphone content	0.1-200 mg
PEG 3350 content	100-1000 mg

Example 16: Preparation of Pharmaceutical Compositions Comprising Hydromorphone

[0071] Pharmaceutical compositions comprising hydromorphone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Hydromorphone content	0.1-100 mg
Poloxamer 407 content	100-1000 mg

Example 17: Preparation of Pharmaceutical Compositions Comprising Fentanyl

[0072] Pharmaceutical compositions comprising hydromorphone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Fentanyl content	0.1-500 mg
PEG 3350 content	100-1000 mg

Example 18: Preparation of Pharmaceutical Compositions Comprising Alfentanyl

[0073] Pharmaceutical compositions comprising alfentanyl may be prepared according to the methods described herein. The compositions may have the following characteristics:

Alfentanyl content	0.01-50 µg
PEG 3350 content	100-1000 mg

Example 19: Preparation of Pharmaceutical Compositions Comprising Sufentanyl

[0074] Pharmaceutical compositions comprising sulfentanyl may be prepared according to the methods described herein. The compositions may have the following characteristics:

Sulfentanyl content	0.01-500 µg
PEG 3350 content	100-1000 mg

Example 20: Preparation of Pharmaceutical Compositions Comprising Remifentanyl

[0075] Pharmaceutical compositions comprising remifentanyl may be prepared according to the methods described herein. The compositions may have the following characteristics:

Remifentanyl content	0.01-500 µg
PEG 3350 content	100-1000 mg

Example 21: Preparation of Pharmaceutical Compositions Comprising Levomethadyl

[0076] Pharmaceutical compositions comprising levomethadyl may be prepared according to the methods described herein. The compositions may have the following characteristics:

Levomethadyl content	0.01-200 mg
Poloxamer 407 content	100-1000 mg

Example 22: Preparation of Pharmaceutical Compositions Comprising Methadone

[0077] Pharmaceutical compositions comprising methadone may be prepared according to the methods described herein. The compositions may have the following characteristics:

Methadone content	0.01-200 mg
PEG 3350 content	100-1000 mg

Example 23: Preparation of Pharmaceutical Compositions Comprising Butorphanol

[0078] Pharmaceutical compositions comprising butorphanol may be prepared according to the methods described herein. The compositions may have the following characteristics:

Butorphanol content	0.1-200 mg
PEG 3350 content	100-1000 mg

Example 24: Preparation of Pharmaceutical Compositions Comprising Dezocine

[0079] Pharmaceutical compositions comprising dezocine may be prepared according to the methods described herein. The compositions may have the following characteristics:

Dezocine content	0.1-200 mg
Poloxamer 407 content	100-1000 mg

Example 25: Preparation of Pharmaceutical Compositions Comprising Nalbuphine

[0080] Pharmaceutical compositions comprising nalbuphine may be prepared according to the methods described herein. The compositions may have the following characteristics:

Nalbuphine content	0.1-200 mg
PEG 3350 content	100-1000 mg

[0081] It is intended that the specification and examples be considered as exemplary only, with the true scope of the invention being indicated by the following claims.

Claims

1. A composition comprising particles having an average diameter of less than 2 mm, wherein
the particles comprise buprenorphine or buprenorphine HCl present in an amount ranging from about 0.2% to about 4% by mass of the particles, and polyethylene glycol (PEG),
wherein the buprenorphine or buprenorphine HCl is encapsulated by the PEG.

2. The composition of claim 1, wherein the PEG has an average molecular weight ranging from about 500 Daltons to about 10,000 Daltons or wherein the PEG is PEG 3350.

3. The composition of claim 1, further comprising a surfactant.

4. A pharmaceutical composition comprising the composition of claim 1 and naloxone.

5. The pharmaceutical composition of claim 4, wherein the composition is formulated for oral administration.

Ansprüche

1. Zusammensetzung, die Partikel mit einem durchschnittlichen Durchmesser von weniger als 2 mm aufweist, wobei
die Partikel Buprenorphin oder Buprenorphin-HCl, das in einer Menge vorhanden ist, die im Bereich von ungefähr 0,2 % bis ungefähr 4 % der Masse der Partikel liegt, und Polyethylenglykol (PEG) umfassen,
wobei das Buprenorphin oder Buprenorphin-HCl durch das PEG eingekapselt ist.

2. Zusammensetzung nach Anspruch 1, wobei das PEG eine durchschnittliche Molekülmasse aufweist, die im Bereich von ungefähr 500 Dalton bis ungefähr 10.000 Dalton liegt oder wobei das PEG PEG 3350 ist.

3. Zusammensetzung nach Anspruch 1, die ferner ein Benetzungsmittel umfasst.

4. Pharmazeutische Zusammensetzung, welche die Zusammensetzung nach Anspruch 1 und Naloxon umfasst.

5. Pharmazeutische Zusammensetzung nach Anspruch 4, wobei die Zusammensetzung für die orale Verabreichung formuliert ist.

Revendications

1. Composition comprenant des particules ayant un diamètre moyen inférieur à 2 mm, dans laquelle
les particules comprennent de la buprénorphine ou de la buprénorphine HCl présente en une quantité dans la plage d'environ 0,2 % à environ 4 % en poids des particules, et du polyéthylène glycol (PEG),
dans laquelle la buprénorphine ou la buprénorphine HCl est encapsulée par le PEG.

2. Composition selon la revendication 1, dans laquelle le PEG a une masse moléculaire moyenne en poids dans la plage d'environ 500 Daltons à environ 10 000 Daltons ou dans laquelle le PEG est le PEG 3350.

3. Composition selon la revendication 1, comprenant en outre un surfactant.

4. Composition pharmaceutique comprenant la composition selon la revendication 1 et de la naloxone.

5. Composition pharmaceutique selon la revendication 4, dans laquelle la composition est formulée pour une administration orale.