A solid oral controlled-release oral dosage form of hydrocodone is disclosed. The dosage form comprising an analgesically effective amount of hydrocodone or a pharmaceutically acceptable salt thereof, and a sufficient amount of a controlled release material to render the dosage form suitable for twice-a-day administration to a human patient, the dosage form providing a c12/cmax ratio of 0.55 to 0.85, said dosage form providing a therapeutic effect for at least about 12 hours.

Patent
   8975271
Priority
Oct 29 1999
Filed
Dec 03 2013
Issued
Mar 10 2015
Expiry
Oct 30 2020
Assg.orig
Entity
unknown
0
461
EXPIRED
1. A twice-a-day solid oral controlled-release dosage form of a bitartrate salt of hydrocodone consisting of
a pharmaceutically acceptable capsule,
immediate release multiparticulates consisting of a first portion of pharmaceutically acceptable inert beads, a first portion of the bitartrate salt of hydrocodone, hydroxypropylmethylcellulose, glidant(s), and optional plasticizer(s), and
controlled release multiparticulates consisting of the remaining portion of the pharmaceutically acceptable inert beads, the remaining portion of the bitartrate salt of hydrocodone, an ammonio methacrylate copolymer, glidant(s), and optional plasticizer(s),
wherein the total amount of the bitartrate salt of hydrocodone in the dosage form is from about 5 mg to about 60 mg,
said dosage form providing an in-vitro release of from 18% to about 42.5% by weight of hydrocodone from the dosage form at one hour, when measured by the USP Basket Method at 100 rpm in 700 ml of Simulated Gastric Fluid (SGF) for 55 minutes at 37° c. and thereafter switching to 900 ml of Simulated Intestinal Fluid (SIF) at 37° c., and
after a first administration to a human patient, providing a c12/cmax hydrocodone ratio of 0.55 to 0.85, a tmax of hydrocodone at from about 2 to 8 hours and a therapeutic effect for about 12 hours.
13. A twice-a-day solid oral controlled-release dosage form of a bitartrate salt of hydrocodone consisting of
a pharmaceutically acceptable capsule,
immediate release multiparticulates consisting of a first portion of pharmaceutically acceptable inert beads, a first portion of the bitartrate salt of hydrocodone, hydroxypropylmethylcellulose, glidant(s), and optional plasticizer(s), and
controlled release multiparticulates consisting of the remaining portion of the pharmaceutically acceptable inert beads, the remaining portion of the bitartrate salt of hydrocodone, an ammonio methacrylate copolymer, glidant(s), and optional plasticizer(s),
wherein the total amount of the bitartrate salt of hydrocodone in the dosage form is from about 5 mg to about 60 mg,
the dosage form providing an in-vitro release of from 18% to about 42.5% by weight of the hydrocodone from the dosage form at one hour, when measured by the USP Basket Method at 100 rpm in 700 ml of Simulated Gastric Fluid (SGF) for 55 minutes at 37° c. and thereafter switching to 900 ml of Simulated Intestinal Fluid (SIF) at 37° c., said dosage form, after a first administration to the patient population, providing a mean tmax of hydrocodone in-vivo at from about 2 to about 8 hours, a mean c12/cmax hydrocodone ratio of 0.55 to 0.85, and a therapeutic effect for about 12 hours.
14. A twice-a-day solid oral controlled-release dosage form of a bitartrate salt of hydrocodone, the dosage form consisting of
a capsule and
two different types of multiparticulates in the form of granules, spheroids, or pellets,
a first type of said multiparticulates consisting of a first portion of pharmaceutically acceptable inert beads, a first portion of the bitartrate salt of hydrocodone, hydroxypropylmethylcellulose, glidant(s), and optional plasticizer(s) and providing an immediate release of hydrocodone, and
a second type of said multiparticulates consisting of the remaining portion of the pharmaceutically acceptable inert beads coated with the remaining portion of the bitartrate salt of hydrocodone, an ammonio methacrylate copolymer, glidant(s), and optional plasticizer(s), and providing a controlled release of hydrocodone,
wherein the total amount of the bitartrate salt of hydrocodone in the dosage form is from about 5 mg to about 60 mg,
said dosage form providing
an in-vitro release of from at least 18% to about 42.5% by weight of hydrocodone from the dosage form at one hour when measured by the USP Basket Method at 100 rpm in 700 ml of Simulated Gastric Fluid (SGF) for 55 minutes at 37° c. and thereafter switching to 900 ml of Simulated Intestinal Fluid (SIF) at 37° c., and
after a first administration to a human patient, a c12/cmax hydrocodone ratio of 0.55 to 0.85 and a tmax of hydrocodone at from about 2 to 8 hours.
15. A twice-a-day solid oral controlled-release dosage form of a bitartrate salt of hydrocodone, the dosage form comprising
two different types of multiparticulates in the form of granules, spheroids, or pellets, the multiparticulates collectively comprising from about 5 mg to about 60 mg of a bitartrate salt of hydrocodone,
a first type of said multiparticulates consisting of a first portion of pharmaceutically acceptable inert beads, a first portion of the bitartrate salt of hydrocodone, hydroxypropylmethylcellulose, glidant(s), and optional plasticizer(s), and providing an immediate release of hydrocodone,
a second type of said multiparticulates comprising the remaining portion of the pharmaceutically acceptable inert beads, the remaining portion of the bitartrate salt of hydrocodone, an ammonio methacrylate copolymer and glidant(s) and providing a controlled release of hydrocodone,
said dosage form providing a dissolution rate in-vitro of hydrocodone from the dosage form when measured by the USP Paddle or basket method at 100 rpm in 900 ml aqueous buffer at a ph of 7.5 at 37° c., such that from about 25 to about 65% by weight hydrocodone is released after 2 hours, from about 45 to about 85% by weight hydrocodone is released after 4 hours, and greater than about 60% by weight hydrocodone is released after 8 hours, wherein
after a first administration to said patient, the dosage form provides a c12/cmax hydrocodone ratio of 0.55 to 0.85 and a tmax of hydrocodone of from about 2 to about 6 hours.
2. The dosage form of claim 1, which provides a c12/cmax ratio of 0.65 to 0.75 after said first administration.
3. The dosage form of claim 1, which provides a dissolution rate in-vitro of the hydrocodone from the dosage form when measured by the USP Basket method at 100 rpm in 900 ml aqueous buffer at a ph of 1.2 at 37° c. from about 25 to about 65% by weight hydrocodone released after 2 hours, from about 45 to about 85% by weight hydrocodone released after 4 hours, and greater than about 60% by weight hydrocodone released after 8 hours.
4. The dosage form of claim 1, which provides a dissolution rate in-vitro of the hydrocodone from the dosage form when measured by the USP Basket method at 100 rpm in 900 ml aqueous buffer at a ph of 7.5 at 37° c. from about 25 to about 65% by weight hydrocodone released after 2 hours, from about 45 to about 85% by weight hydrocodone released after 4 hours, and greater than about 60% by weight hydrocodone released after 8 hours.
5. The dosage form of claim 1, which provides a tmax of hydrocodone in said patient at from about 3 to about 7 hours after said first administration of the dosage form.
6. The dosage form of claim 1, which provides a tmax of hydrocodone in said patient at from about 4 to about 6 hours after said first administration of the dosage form.
7. The dosage form of claim 1, which provides a plasma concentration of hydrocodone of at least 8 ng/ml at from about 2 to about 8 hours after said first administration and provides a plasma concentration of hydrocodone of at least 6 ng/ml at about 12 hours after said first administration, based on oral administration of a dosage form containing 15 mg hydrocodone bitartrate.
8. The dosage form of claim 7, which provides a plasma concentration of hydrocodone of at least 8 ng/ml at from about 3 to about 7 hours after said first administration.
9. The dosage form of claim 1, which maintains a plasma concentration of hydrocodone within 80% of cmax for about 1 to about 9 hours during the 12 hour dosing interval.
10. The dosage form of claim 1, which maintains a plasma concentration of hydrocodone within 80% of cmax for about 4 to about 8 hours during the 12 hour dosing interval.
11. The dosage form of claim 1, which maintains a plasma concentration of hydrocodone within 90% of cmax for about 1 to about 6.5 hours during the 12 hour dosing interval.
12. The dosage form of claim 1, which maintains a plasma concentration of hydrocodone within 90% of cmax for about 2 to about 5 hours during the 12 hour dosing interval.
16. The dosage form of claim 1, wherein the remaining portion of the pharmaceutically acceptable inert beads is coated with the remaining portion of the bitartrate salt of hydrocodone, the ammonio methacrylate copolymer and glidant(s).
17. The dosage form of claim 1, wherein the multiparticulates are in the form of spheroids.
18. The dosage form of claim 17, wherein the spheroids are in a form of spherical granules having a diameter of between 0.1 mm and 2.5 mm.
19. The dosage form of claim 18, wherein the spherical granules have a diameter of between 0.5 mm and 2 mm.
20. The dosage form of claim 1, wherein the multiparticulates are in the form of granules.
21. The dosage form of claim 1, wherein at least one of the glidants is talc.
22. The dosage form of claim 1, wherein the ammonio methacrylate copolymer is a copolymer of acrylic and methacrylic ester with a molar ratio of ammonium groups to neutral (meth)acrylic esters of 1:40.
23. The dosage form of claim 15, wherein the second type of said multiparticulates consists of the remaining portion of the pharmaceutically acceptable inert beads, the remaining portion of the bitartrate salt of hydrocodone, the ammonio methacrylate copolymer, glidant(s), and optional plasticizer(s).

This application is a continuation of U.S. Ser. No. 13/833,263, filed on Mar. 15, 2013, which is a continuation of U.S. Ser. No. 12/982,386, filed on Dec. 30, 2010, which is a continuation of U.S. Ser. No. 10/864,829, filed on Jun. 9, 2004, now U.S. Pat. No. 7,943,174, which is a continuation of U.S. Ser. No. 09/702,283, filed on Oct. 30, 2000, which claims priority from U.S. Provisional Application Ser. No. 60/162,541 filed Oct. 29, 1999, all hereby incorporated by reference.

Due to the difficulties presented by the pharmacotherapy of pain, particularly chronic pain, opioid analgesics are ideal drugs to be administered as controlled release formulations. The present invention relates to a solid, controlled-release oral dosage form for use in the treatment of pain.

It is the intent of all controlled (slow) release formulations to provide a longer period of pharmacological action after administration than is ordinarily obtained after administration of immediate-release dosage forms. Such longer periods of response provide for many therapeutic benefits that are not achieved with corresponding short acting, immediate release preparations. Thus, therapy may be continued without interrupting the sleep of the patient, which is of special importance, for example, when treating a patient for moderate to severe pain (e.g., a post-surgery patient, a cancer patient, etc.), or for those patients who experience migraine headaches on awakening, as well as for the debilitated patient for whom sleep is essential.

Unless conventional rapid acting drug therapy is carefully administered at frequent intervals to maintain effective steady state plasma concentrations of the drug, peaks and valleys in the plasma level of the active drug occurs because of the rapid absorption, systemic excretion of the compound and through metabolic inactivation, thereby producing special problems in maintenance therapy of the patient. A further general advantage of longer acting drug preparations is improved patient compliance resulting from the avoidance of missed doses through patient forgetfulness.

It is known in the pharmaceutical art to prepare compositions which provide for controlled release of pharmacologically active substances contained in the compositions after oral administration to humans and animals. Such slow release compositions are used to delay absorption of a medicament until it has reached certain portions of the alimentary tract. Such controlled release of a medicament in the alimentary tract further maintains a desired concentration of said medicament in the blood stream for a longer duration than would occur if conventional rapid release dosage forms are administered.

The prior art teaching of the preparation and use of compositions providing the controlled release of an active compound from a carrier is basically concerned with the release of the active substance into the physiologic fluid of the alimentary tract. However, it is generally recognized that the mere presence of an active substance in the gastrointestinal fluids does not, by itself, ensure bioavailability.

In order to be absorbed, the active drug substance must be in solution. The time required for a given proportion of an active substance from a unit dosage form is determined as the proportion of the amount of active drug substance released from a unit dosage form over a specified time base by a test method conducted under standardized conditions. The physiologic fluids of the gastrointestinal tract are the media for determining dissolution time. The present state of the art recognizes many satisfactory test procedures to measure dissolution time for pharmaceutical compositions, and these test procedures are described in official compendia worldwide.

Although there are many diverse factors which influence the dissolution of a drug substance from its carrier, the dissolution time determined for a pharmacologically active substance from the specific composition is relatively constant and reproducible. Among the different factors which may affect the dissolution time are the surface area of the drug substance presented to the dissolution solvent medium, the pH of the solution, the solubility of the substance in the specific solvent medium, and the driving forces of the saturation concentration of dissolved materials in the solvent medium. Thus, the dissolution concentration of an active drug substance is dynamically modified in its steady state as components are removed from the dissolution medium through absorption across the tissue site. Under physiologic conditions, the saturation level of the dissolved materials is replenished from the dosage form reserve to maintain a relatively uniform and constant dissolution concentration in the solvent medium providing for a steady state absorption.

The transport across a tissue absorption site of the gastrointestinal tract is influenced by the Donnan osmotic equilibrium forces on both sides of the membrane since the direction of the driving force is the difference between the concentrations of active substance on either side of the membrane, i.e., the amount dissolved in the gastrointestinal fluids and the amount present in the blood. Since the blood concentrations are constantly being modified by dilution, circulatory changes, tissue storage, metabolic conversion and systemic excretion, the flow of active materials is directed from the gastrointestinal tract into the blood stream.

Various techniques have been used to prepare controlled release dosage forms. Specially coated pellets, tablets and capsules wherein the slow release of the active medicament is brought about through selective breakdown of the coating of the preparation or through compounding with a special matrix to affect the release of a drug are known in the art. Certain controlled release formulations provide for related sequential release of a single dose of an active compound at predetermined periods after administration.

Specific examples of controlled release opioid formulations reported in the patent literature include, for example, those disclosed in U.S. Pat. Nos. 4,990,341 and 4,844,909 (Goldie, et al.), both assigned to the assignee of the present invention and incorporated herein by reference, describe hydromorphone compositions wherein the dissolution rate in-vitro of the dosage form, when measured by the USP Paddle or Basket Method at 100 rpm in 900 ml aqueous buffer (pH between 1.6 and 7.2) at 37° C., is between 12.5 and 42.5% (by wt) hydromorphone released after 1 hour, between 25 and 55% (by wt) released after 2 hours, between 45 and 75% (by wt) released after 4 hours and between 55 and 85% (by wt) released after 6 hours, the in-vitro release rate being independent of pH between pH 1.6 and 7.2 and chosen such that the peak plasma concentration of hydromorphone obtained in-vivo occurs between 2 and 4 hours after administration of the dosage form. At least 12 hours of pain relief is obtained with these hydromorphone formulations.

It is considered highly desirable to provide controlled-release dosage formulations of other opioid analgesic drugs which can be used for moderate pain. It is further considered highly desirable to provide such controlled-release formulations with pharmacokinetic properties which provide the most effective pain management in patients in need of pain therapy.

It is an object of the present invention to substantially improve the efficiency and quality of pain management in human patients experiencing moderate pain.

It is an object of the present invention to provide bioavailable hydrocodone formulations that substantially improve the efficiency and quality of pain management.

It is yet another object of the present invention to provide bioavailable controlled-release hydrocodone formulations which provide a substantially increased duration of effect as compared to immediate release hydrocodone formulations, but which provide an early onset of analgesia.

It is a further object of the invention to provide orally administrable controlled release opioid formulations suitable for twice-a-day administration which provide an early onset of therapeutic effect and which, after rising to a maximum concentration during the dosage interval, provide a relatively flat serum plasma profile, meaning that the plasma level of the opioid provides a C12/Cmax ratio of 0.55 to 0.85, and which provides effective pain relief to the patient. In alternate embodiments, the dosage form provides a C12/Cmax ratio of 0.65 to 0.75

The above objects and others are attained by virtue of the present invention, which in certain embodiments, provides a solid oral controlled-release dosage form comprising an analgesically effective amount of hydrocodone or a pharmaceutically acceptable salt thereof and a sufficient amount of a controlled release material to render the dosage form suitable for twice-a-day administration, the dosage form after single administration to a human patient or a population of patients, providing a time to peak plasma concentration of hydrocodone in-vivo, preferably at from about 2 to about 8 hours (Tmax), and after attaining a maximum concentration, providing a C12/Cmax ratio of 0.55 to 0.85.

In certain preferred embodiments, the controlled release dosage form provides an in-vitro release of from 18% to about 42.5% by weight of the hydrocodone or salt thereof from the dosage form at one hour when measured by the USP Basket Method at 100 rpm in 700 ml of Simulated Gastric Fluid (SGF) for 55 minutes at 37° C. and thereafter switching to 900 ml of Simulated Intestinal Fluid (SIF) at 37° C.

In certain preferred embodiments, the dissolution rate in-vitro of the hydrocodone dosage form when measured by the USP Basket method at 100 rpm in 900 ml aqueous buffer at a pH of 1.2 and 7.5 at 37° C. is from about 25 to about 65% by weight of the hydrocodone or salt thereof released after 2 hours, from about 45 to about 85% by weight of the hydrocodone or salt thereof released after 4 hours, and greater than about 60% by weight of the hydrocodone or salt thereof released after 8 hours. Although the in-vitro release rate may be either pH-independent or pH-dependent as desired, in preferred embodiments of the invention the release of hydrocodone is pH-independent.

In certain preferred embodiments, there is provided a controlled release dosage form comprising a therapeutically effective amount of hydrocodone wherein the dosage form provides a hydrocodone plasma concentration of at least 5 or 6 ng/ml, at 12 hours after administration and provides a plasma concentration of at least about 8 ng/ml at from about 2 to about 8 hours after administration.

In other preferred embodiments of the invention, there is provided a twice-a-day oral controlled release dosage form of hydrocodone which provides a Cmax of hydrocodone which is less than about 50% of the Cmax of an equivalent dose of an immediate release hydrocodone reference formulation (e.g. Lortab®), and which provides effective analgesia during the 12 hour dosage interval.

In other preferred embodiments of the invention, there is provided a twice-a-day controlled release dosage form of hydrocodone wherein the dosage form provides a time to 80% Cmax which is from about 90% to about 150%, preferably from about 90% to about 110%, of the time to 80% Cmax of an equivalent dose of immediate release hydrocodone reference formulation (e.g. Lortab). Preferably, the time to 80% Cmax of hydrocodone for the controlled release dosage form being from about 0.5 to about 1.5 hours, most preferably from about 0.8 to about 1.2 hours. In alternate embodiments, the time to 80% Cmax of hydrocodone for the controlled release dosage form is from about 0.75 to about 2.0 hours, most preferably from about 0.9 to about 1.5 hours.

In other preferred embodiments of the invention, there is provided a twice-a-day controlled release dosage form of hydrocodone wherein the dosage form provides a time to 90% Cmax which is about 150% to about 400%, preferably from about 150% to about 250%, of the time to 90% Cmax of an equivalent dose of immediate release hydrocodone reference formulation. Preferably, the time to 90% Cmax of hydrocodone for the controlled release dosage form is from about 1.5 to about 2.5 hours, most preferably from about 1.8 to about 2.2 hours. In alternate embodiments, the time to 90% Cmax of hydrocodone for the controlled release dosage form is from about 1.5 to about 4.0 hours, most preferably from about 1.8 to about 2.5 hours.

In other preferred embodiments of the invention, there is provided a twice-a-day controlled release dosage form of hydrocodone wherein the dosage form maintains a plasma concentration within 80% of Cmax from about 0.5 to 10 hours, preferably from about 1 to about 9 hours or from about 4 to about 8 hours.

In other preferred embodiments of the invention, there is provided a twice-a-day controlled release dosage form of hydrocodone which maintains a plasma concentration of hydrocodone within 90% of Cmax from about 1 to 6.5 hours, preferably from about 2 to about 5 hours or from about 2 to about 6.5 hours.

In other preferred embodiments of the invention, there is provided a twice-a-day controlled release dosage form of hydrocodone which provides a mean in-vivo absorption rate from administration to Tmax from about 1.5 mg/hour to about 5 mg/hour and provides a mean rate of absorption from Tmax to the end of the dosing interval which is less than about 0.5 mg/hour based on oral administration of a dosage form containing 15 mg hydrocodone bitartrate. Preferably, the dosage form provides a mean in-vivo absorption rate from administration to Tmax from about 2 mg/hour to about 4 mg/hour and provides a mean in-vivo absorption rate Tmax to the end of the 12 hour dosing interval which is from about 0.08 mg/hour to about 0.4 mg/hour based on oral administration of a dosage form containing 15 mg hydrocodone bitartrate.

In other preferred embodiments of the invention, there is provided a twice-a-day oral controlled release hydrocodone dosage form which provides a rate of absorption during the time period from Tmax to about 12 hours after oral administration of the dosage form which is from about 55% to about 85% of the rate of elimination during the same time period.

The above embodiments of the invention, as well as other embodiments, preferably provide a time to Tmax at a time point 3 to 4 times later than the Tmax provided by an equivalent dose of an immediate release hydrocodone reference. Preferably, the Tmax provided by the sustained release formulation occurs at from about 2 to about 8 hours, from about 3 to about 7 hours or from about 4 to about 6 hours after oral administration.

The present invention is further directed to hydrocodone formulations which provide a Cmax of hydrocodone which is less than about 50%, preferably less than about 40% of the Cmax provided by an equivalent dose of an immediate release reference product.

For example, it was surprisingly discovered that when hydrocodone is formulated in the delivery system as disclosed in U.S. Pat. Nos. 4,861,598 and 4,970,075, the Cmax of hydrocodone provided by the delivery system as a percentage of the Cmax of an immediate release reference product was considerably lower than the same calculation for oxycodone formulated in the same delivery system. This phenomena is evident, regardless of the fact that the controlled release oxycodone and hydrocodone formulations exhibited similar in-vitro dissolution parameters.

When the present invention is formulated using the delivery systems U.S. Pat. Nos. 4,861,598 and 4,970,075, the Cmax of the delivery system as a percentage of the Cmax of the immediate release reference product is less than about 50%, and less than 40% in preferred embodiments, whereas oxycodone, exhibits a calculation of greater than 50%.

“Hydrocodone” is defined for purposes of the invention as including hydrocodone free base, as well as pharmaceutically acceptable salts and complexes of hydrocodone.

The term “USP Paddle or Basket Method” is the Paddle and Basket Method described, e.g., in U.S. Pharmacopoeia XXII (1990), herein incorporated by reference.

The term “pH-dependent” for purposes of the present invention is defined as having characteristics (e.g. dissolution) which vary according to environmental pH.

The term “pH-independent” for purposes of the present invention is defined as having characteristics (e.g., dissolution) which are substantially unaffected by pH.

The term “bioavailability” is defined for purposes of the present invention as the extent to which the drug (e.g., hydrocodone) is absorbed from the unit dosage forms.

The term “controlled-release” is defined for purposes of the present invention as the release of the drug (e.g., hydrocodone) at such a rate that blood (e.g., plasma) concentrations are maintained within the therapeutic range but below toxic concentrations over a period of time of about 12 hours or longer.

The term “Cmax” denotes the maximum plasma concentration obtained during the dosing interval.

The term “Tmax” denotes the time to maximum plasma concentration (Cmax).

The term T1/2 (abs) denotes the amount of time necessary for one-half of the absorbable dose of opioid to be transferred to plasma.

The term “steady state” means that a plasma concentration for a given drug has been achieved and which is maintained with subsequent doses of the drug at a concentration which is at or above the minimum effective therapeutic concentration and is below the minimum toxic plasma concentration for a given drug. For opioid analgesics, the minimum effective therapeutic concentration will be a partially determined by the amount of pain relief achieved in a given patient. It will be well understood by those skilled in the medical art that pain measurement is highly subjective and great individual variations may occur among patients.

The terms “maintenance therapy” and “chronic therapy” are defined for purposes of the present invention as the drug therapy administered to a patient after a patient is titrated with an opioid analgesic to a steady state as defined above.

The term “minimum effective analgesic concentration” or “MEAC” with respect to concentrations of opioids such as hydrocodone is very difficult to quantify. However, there is generally a minimally effective analgesic concentration of plasma hydrocodone below which no analgesia is provided. While there is an indirect relationship between, e.g., plasma hydrocodone levels and analgesia, higher and prolonged plasma levels are generally associated with superior pain relief. There is a lag time or hysteresis, between the time of peak plasma hydrocodone-levels and the time of peak drug effects. This holds true for the treatment of pain with opioid analgesics in general.

The term “mean resonance time” (MRT) is defined as the average time a drug molecule stays in the body. This calculation, which is a function of absorption, distribution and elimination, is dependent in part, on the dosage form containing the active ingredient.

For purposes of the invention, unless further specified, the term “a patient” means that the discussion (or claim) is directed to the pharmacokinetic parameters of an individual patient or subject.

The term “population of patients” means that the discussion (or claim) is directed to the mean pharmacokinetic parameters of at least two patients or subjects.

The term “breakthrough pain” means pain which the patient experiences despite the fact that the patient is being administered generally effective amounts of the sustained release solid oral dosage forms of the invention containing hydromorphone.

The term “rescue” refers to a dose of an analgesic which is administered to a patient experiencing breakthrough pain.

The term “effective pain management” means an objective evaluation of a human patient's response (pain experienced versus side effects) to analgesic treatment by a physician as well as subjective evaluation of therapeutic treatment by the patient undergoing such treatment. One skilled in the art will understand that effective analgesia will vary according to many factors, including individual patient variability.

The term “immediate release hydrocodone reference formulation” for purposes of the present invention, is an equivalent amount of the hydrocodone portion of Lortab®, commercially available from UCB Pharma, Inc, or a pharmaceutical product that provides an immediate release of hydrocodone or a salt thereof.

For purposes of the invention, the controlled release formulations disclosed herein and the immediate release control formulations are dose proportional. In such formulations, the pharmacokinetic parameters (e.g. AUC and Cmax) increase linearly from one dosage strength to another. Therefore the pharmacokinetic parameters of a particular dose can be inferred from the parameters of a different dose of the same formulation.

For purposes of the invention, unless otherwise specified, the pharmacokinetic parameters disclosed herein are based on the administration of a single dose of a hydrocodone formulation to an individual patient. Pharmacokinetic parameters based on a patient population will be specified as “mean” data.

The term “first administration” means a single dose of the present invention at the initiation of therapy to an individual patient or a patient population.

The controlled-release oral solid dosage forms of the present invention surprisingly may be opioid-sparing. It is possible that the controlled-release oral solid dosage forms of the present invention may be dosed at a substantially lower daily dosage in comparison to conventional immediate-release products, with no difference in analgesic efficacy. At comparable daily dosages, greater efficacy may result with the use of the controlled-release oral solid dosage forms of the present invention in comparison to conventional immediate-release products.

The figures attached herewith are illustrative of embodiments of the invention and are not meant to limit the scope of the invention as encompassed by the claims.

FIG. 1 is a graphical representation of the mean hydrocodone plasma concentration of Example 1, Example 2, Example 3 and an equivalent dose of immediate release hydrocodone.

FIG. 2 is a graphical representation of the mean plasma concentration of Example 1, Example 2 and Example 3, against different samples of controlled release oxycodone manufactured in accordance with the procedures of Example 4, and different samples of controlled release morphine manufactured in accordance with the procedures of Example 5.

FIG. 3 is a graphical representation of the % fraction hydrocodone absorbed over time of Example 1, Example 2, Example 3 and an equivalent dose of immediate release hydrocodone.

The above embodiments of the invention can be provided by a wide variety of controlled release formulations known to those skilled in the art. For example, suitable controlled release dosage forms are disclosed in U.S. Pat. Nos. 4,861,598 and 4,970,075, hereby incorporated by reference

In certain embodiments of the present invention, an effective amount of opioid in immediate release form is included in the formulation. The immediate release form of the opioid is included in an amount which is effective to shorten the time to maximum concentration of the opioid in the blood (e.g., plasma), such that the Tmax is shortened to a time of e.g., from about 2 to about 5 hours, or from about 2 to about 4 hours. It has been discovered that by including such an effective amount of immediate release opioid in the unit dose, the experience of relatively higher levels of pain in patients is significantly reduced. In such embodiments, an effective amount of the opioid in immediate release form may be coated onto the substrates of the present invention. For example, where the extended release opioid from the formulation is due to a controlled release coating, the immediate release layer would be overcoated on top of the controlled release coating. On the other hand, the immediate release layer may be coated onto the surface of substrates wherein the opioid is incorporated in a controlled release matrix. Where a plurality of the sustained release substrates comprising an effective unit dose of the opioid (e.g., multiparticulate systems including pellets, spheres, beads and the like) are incorporated into a hard gelatin capsule, the immediate release portion of the opioid dose may be incorporated into the gelatin capsule via inclusion of the sufficient amount of immediate release opioid as a powder or granulate within the capsule. Alternatively, the gelatin capsule itself may be coated with an immediate release layer of the opioid. One skilled in the art would recognize still other alternative manners of incorporating the immediate release opioid portion into the unit dose. Such alternatives are deemed to be encompassed by the appended claims.

One advantage of the opioid dosage forms of the present invention is that therapeutic concentrations are generally achieved substantially without significant increases in the intensity and/or degree of concurrent side effects, such as nausea, vomiting, or drowsiness, which are often associated with high blood concentrations of opioids. There is also evidence to suggest that the use of the present dosage forms lead to a reduced risk of drug addiction.

The controlled release oral dosage forms of the present invention preferably include from about 0.5 mg to about 1250 mg hydrocodone or an equivalent amount of a pharmaceutically acceptable salt thereof. In more preferred embodiments, the dosage form can include from about 5 mg to about 60 mg, e.g. 15 mg. Suitable pharmaceutically acceptable salts of hydrocodone include hydrocodone bitartrate, hydrocodone bitartrate hydrate, hydrocodone hydrochloride, hydrocodone p-toluenesulfonate, hydrocodone phosphate, hydrocodone thiosemicarbazone, hydrocodone sulfate, hydrocodone trifluoroacetate, hydrocodone hemipentahydrate, hydrocodone pentafluoropropionate, hydrocodone p-nitrophenylhydrazone, hydrocodone o-methyloxime, hydrocodone semicarbazone, hydrocodone hydrobromide, hydrocodone mucate, hydrocodone oleate, hydrocodone phosphate dibasic, hydrocodone phosphate monobasic, hydrocodone inorganic salt, hydrocodone organic salt, hydrocodone acetate trihydrate, hydrocodone bis(heptafluorobutyrate), hydrocodone bis(methylcarbamate), hydrocodone bis(pentafluoropropionate), hydrocodone bis(pyridine carboxylate), hydrocodone bis(trifluoroacetate), hydrocodone chlorhydrate, and hydrocodone sulfate pentahydrate. Preferably, the hydrocodone is present as the bitartrate salt.

The dosage forms of the present invention may further include one or more additional drugs which may or may not act synergistically with the hydrocodone analgesics of the present invention. Examples of such additional drugs include non-steroidal anti-inflammatory agents, including ibuprofen, diclofenac, naproxen, benoxaprofen, flurbiprofen, fenoprofen, flubufen, ketoprofen, indoprofen, piroprofen, carprofen, oxaprozin, pramoprofen, muroprofen, trioxaprofen, suprofen, aminoprofen, tiaprofenic acid, fluprofen, bucloxic acid, indomethacin, sulindac, tolmetin, zomepirac, tiopinac, zidometacin, acemetacin, fentiazac, clidanac, oxpinac, mefenamic acid, meclofenamic acid, flufenamic acid, niflumic acid tolfenamic acid, diflurisal, flufenisal, piroxicam, sudoxicam or isoxicam, and the like. Such non-steroidal anti-inflammatory agents also include cyclo-oxygenase inhibitors such as celecoxib (SC-58635), DUP-697, flosulide (CGP-28238), meloxicam, 6-methoxy-2 naphthylacetic acid (6-MNA), Vioxx (MK-966), nabumetone (prodrug for 6-MNA), nimesulide, NS-398, SC-5766, SC-58215, and T-614. as amantadine (1-aminoadamantine), and memantine (3,5 dimethylaminoadamantone), their mixtures and pharmaceutically acceptable salts thereof.

Other additional drugs include nontoxic NMDA receptor antagonists such dextrorphan, dextromethorphan, 3-(1-napthalenyl)-5-(phosphonomethyl)-L-phenylalanine, 3-(1-naphthalenyl)-5-(phosphonomethyl)-DL-phenylalanine, 1-(3,5-dimethylphenyl)naphthalene, and 2-(3,5-dimethylphenyl)naphthalene, 2SR,4RS-4-(((1H-Tetrazol-5-yl)methyl)oxy)piperidine-2-carboxylic acid; 2SR,4RS-4-((((1H-Tetrazol-5-yl)methyl)oxy)methyl)piperidine-2-carboxylic acid; E and Z 2SR-4-(O-(1H-Tetrazol-5-yl)methyl)ketoximino)piperidine-2-carboxylic acid; 2SR,4RS-4-((1H-Tetrazol-5-yl)thio)piperidine-2-carboxylic acid; 2SR,4RS-4-((1H-Tetrazol-5-yl)thio)piperidine-2-carboxylic acid; 2SR,4RS-4-(5-mercapto-1H-Tetrazol-1-yl)piperidine-2-carboxylic acid; 2SR,4RS-4-(5-mercapto-2H-Tetrazol-2-yl)piperidine-2-carboxylic acid; 2SR,4RS-4-(5-mercapto-1H-Tetrazol-1-yl)piperidine-2-carboxylic acid; 2SR,4RS-4-(5-mercapto-2H-Tetrazol-2-yl)piperidine-2-carboxylic acid; 2SR,4RS-4-(((1H-Tetrazol-5-yl)thio)methyl)piperidine-2-carboxylic acid; 2SR,4RS-4-((5-mercapto-1H-Tetrazol-1-yl)methyl)piperidine-2-carboxylic acid; or 2 SR,4RS-4-((5-mercapto-2H-Tetrazol-2-yl)methyl)piperidine-2-carboxylic acid, their mixtures and pharmaceutically acceptable salts thereof.

Other suitable additional drugs which may be included in the dosage forms of the present invention include acetaminophen, aspirin, neuro-active steroids (such as those disclosed in U.S. Ser. No. 09/026,520, filed Feb. 20, 1998, hereby incorporated by reference) and other non-opioid analgesics.

For example, if a second (non-opioid) drug is included in the formulation, such drug may be included in controlled release form or in immediate release form. The additional drug may be incorporated into the controlled release matrix along with the opioid; incorporated into the controlled release coating; incorporated as a separated controlled release layer or immediate release layer; or may be incorporated as a powder, granulation, etc., in a gelatin capsule with the substrates of the present invention.

In certain preferred embodiments of the present invention, an effective amount of hydrocodone in immediate release form is included in the controlled release unit dose hydrocodone formulation to be administered. The immediate release form of the hydrocodone is included in an amount which is effective to shorten the time to Cmax of the hydrocodone in the blood (e.g., plasma). In such embodiments, an effective amount of the hydrocodone in immediate release form may be coated onto the substrates of the present invention. For example, where the extended release hydrocodone from the formulation is due to a controlled release coating, the immediate release layer would be overcoated on top of the controlled release coating. On the other hand, the immediate release layer may be coated onto the surface of substrates wherein the hydrocodone is incorporated in a controlled release matrix. Where a plurality of the sustained release substrates comprising an effective unit dose of the hydrocodone (e.g., multiparticulate systems including pellets, spheres, beads and the like) are incorporated into a hard gelatin capsule, the immediate release portion of the opioid dose may be incorporated into the gelatin capsule via inclusion of the sufficient amount of immediate release hydrocodone as a powder or granulate within the capsule. Alternatively, the gelatin capsule itself may be coated with an immediate release layer of the hydrocodone. One skilled in the art would recognize still other alternative manners of incorporating the immediate release hydromorphone portion into the unit dose. Such alternatives are deemed to be encompassed by the appended claims. It has been discovered that by including such an effective amount of immediate release hydrocodone in the unit dose, the experience of relatively higher levels of pain in patients is significantly reduced.

The controlled-release dosage form may optionally include a controlled release material which is incorporated into a matrix along with the hydrocodone, or which is applied as a sustained release coating over a substrate comprising the drug (the term “substrate” encompassing beads, pellets, spheroids, tablets, tablet cores, etc). The controlled release material may be hydrophobic or hydrophilic as desired. The oral dosage form according to the invention may be provided as, for example, granules, spheroids, pellets (hereinafter collectively referred to as “multiparticulates”). An amount of the multiparticulates which is effective to provide the desired dose of opioid over time may be placed in a capsule or may be incorporated in any other suitable oral solid form, e.g., compressed into a tablet. On the other hand, the oral dosage form according to the present invention may be prepared as a tablet core coated with a controlled-release coating, or as a tablet comprising a matrix of drug, controlled release material, and optionally other pharmaceutically desirable ingredients (e.g., diluents, binders, colorants, lubricants, etc.).

In certain preferred embodiments of the present invention, the controlled-release formulation is achieved via a matrix (e.g. a matrix tablet) which includes a controlled-release material as set forth above. A dosage form including a controlled-release matrix provides in-vitro dissolution rates of the opioid within the preferred ranges and that releases the opioid in a pH-dependent or pH-independent manner. The materials suitable for inclusion in a controlled-release matrix will depend on the method used to form the matrix. The oral dosage form may contain between 1% and 80% (by weight) of at least one hydrophilic or hydrophobic controlled release material.

A non-limiting list of suitable controlled-release materials which may be included in a controlled-release matrix according to the invention include hydrophilic and/or hydrophobic materials, such as gums, cellulose ethers, acrylic resins, protein derived materials, waxes, shellac, and oils such as hydrogenated castor oil, hydrogenated vegetable oil. However, any pharmaceutically acceptable hydrophobic or hydrophilic controlled-release material which is capable of imparting controlled-release of the opioid may be used in accordance with the present invention. Preferred controlled-release polymers include alkylcelluloses such as ethylcellulose, acrylic and methacrylic acid polymers and copolymers, and cellulose ethers, especially hydroxyalkylcelluloses (especially hydroxypropylmethylcellulose) and carboxyalkylcelluloses. Preferred acrylic and methacrylic acid polymers and copolymers include methyl methacrylate, methyl methacrylate copolymers, ethoxyethyl methacrylates, cynaoethyl methacrylate, aminoalkyl methacrylate copolymer, poly(acrylic acid), poly(methacrylic acid), methacrylic acid alkylamine copolymer, poly(methyl methacrylate), poly(methacrylic acid) (anhydride), polymethacrylate, polyacrylamide, poly(methacrylic acid anhydride), and glycidyl methacrylate copolymers. Certain preferred embodiments utilize mixtures of any of the foregoing controlled-release materials in the matrices of the invention.

The matrix also may include a binder. In such embodiments, the binder preferably contributes to the controlled-release of the hydrocodone from the controlled-release matrix.

Preferred hydrophobic binder materials are water-insoluble with more or less pronounced hydrophilic and/or hydrophobic trends. Preferably, the hydrophobic binder materials useful in the invention have a melting point from about 30 to about 200° C., preferably from about 45 to about 90° C. When the hydrophobic material is a hydrocarbon, the hydrocarbon preferably has a melting point of between 25° and 90° C. Of the long chain (C8-C50) hydrocarbon materials, fatty (aliphatic) alcohols are preferred. The oral dosage form may contain up to 80% (by weight) of at least one digestible, long chain hydrocarbon.

Preferably, the oral dosage form contains up to 80% (by weight) of at least one polyalkylene glycol. Specifically, the hydrophobic binder material may comprise natural or synthetic waxes, fatty alcohols (such as lauryl, myristyl, stearyl, cetyl or preferably cetostearyl alcohol), fatty acids, including but not limited to fatty acid esters, fatty acid glycerides (mono-, di-, and tri-glycerides), hydrogenated fats, hydrocarbons, normal waxes, stearic aid, stearyl alcohol and hydrophobic and hydrophilic materials having hydrocarbon backbones. Suitable waxes include, for example, beeswax, glycowax, castor wax and carnauba wax. For purposes of the present invention, a wax-like substance is defined as any material which is normally solid at room temperature and has a melting point of from about 30 to about 100° C.

Preferred hydrophobic binder materials which may be used in accordance with the present invention include digestible, long chain (C8-C50, especially C12-C40), substituted or unsubstituted hydrocarbons, such as fatty acids, fatty alcohols, glyceryl esters of fatty acids, mineral and vegetable oils, natural and synthetic waxes and polyalkylene glycols. Hydrocarbons having a melting point of between 25° and 90° C. are preferred. Of the long-chain hydrocarbon binder materials, fatty (aliphatic) alcohols are preferred in certain embodiments. The oral dosage form may contain up to 80% (by weight) of at least one digestible, long chain hydrocarbon.

In certain preferred embodiments, a combination of two or more hydrophobic binder materials are included in the matrix formulations. If an additional hydrophobic binder material is included, it is preferably selected from natural and synthetic waxes, fatty acids, fatty alcohols, and mixtures of the same. Examples include beeswax, carnauba wax, stearic acid and stearyl alcohol. This list is not meant to be exclusive.

One particular suitable controlled-release matrix comprises at least one water soluble hydroxyalkyl cellulose, at least one C12-C36, preferably C14-C22, aliphatic alcohol and, optionally, at least one polyalkylene glycol. The hydroxyalkyl cellulose is preferably a hydroxy (C1 to C6) alkyl cellulose, such as hydroxypropylcellulose, hydroxypropylmethylcellulose and, especially, hydroxyethyl cellulose. The amount of the at least one hydroxyalkyl cellulose in the present oral dosage form will be determined, inter alia, by the precise rate of opioid release required. The aliphatic alcohol may be, for example, lauryl alcohol, myristyl alcohol or stearyl alcohol. In particularly preferred embodiments of the present oral dosage form, however, the at least one aliphatic alcohol is cetyl alcohol or cetostearyl alcohol. The amount of the aliphatic alcohol in the present oral dosage form will be determined, as above, by the precise rate of opioid release required. It will also depend on whether at least one polyalkylene glycol is present in or absent from the oral dosage form. In the absence of at least one polyalkylene glycol, the oral dosage form preferably contains between 20% and 50% (by wt) of the aliphatic alcohol. When a polyalkylene glycol is present in the oral dosage form, then the combined weight of the aliphatic alcohol and the polyalkylene glycol preferably constitutes between 20% and 50% (by wt) of the total dosage.

In one preferred embodiment, the ratio of, e.g., the at least one hydroxyalkyl cellulose or acrylic resin to the at least one aliphatic alcohol/polyalkylene glycol determines, to a considerable extent, the release rate of the opioid from the formulation. A ratio of the hydroxyalkyl cellulose to the aliphatic alcohol/polyalkylene glycol of between 1:2 and 1:4 is preferred, with a ratio of between 1:3 and 1:4 being particularly preferred.

The polyalkylene glycol may be, for example, polypropylene glycol or, which is preferred, polyethylene glycol. The number average molecular weight of the at least one polyalkylene glycol is preferred between 1,000 and 15,000 especially between 1,500 and 12,000.

Another suitable controlled-release matrix comprises an alkylcellulose (especially ethylcellulose), a C12 to C36 aliphatic alcohol and, optionally, a polyalkylene glycol.

In addition to the above ingredients, a controlled-release matrix may also contain suitable quantities of other materials, e.g., diluents, lubricants, binders, granulating aids, colorants, flavorants and glidants that are conventional in the pharmaceutical art.

In order to facilitate the preparation of a solid, controlled-release oral dosage form according to this invention there is provided, in a further aspect of the present invention, a process for the preparation of a solid, controlled-release oral dosage form according to the present invention comprising incorporating opioids or a salt thereof in a controlled-release matrix. Incorporation in the matrix may be effected, for example, by

(a) forming granules comprising at least one hydrophobic and/or hydrophilic material as set forth above (e.g., a water soluble hydroxyalkyl cellulose) together with the hydrocodone;

(b) mixing the at least one hydrophobic and/or hydrophilic material-containing granules with at least one C12-C36 aliphatic alcohol, and

(c) optionally, compressing and shaping the granules.

The granules may be formed by any of the procedures well-known to those skilled in the art of pharmaceutical formulation. For example, in one preferred method, the granules may be formed by wet granulating hydroxyalkyl cellulose/opioid with water. In a particularly preferred embodiment of this process, the amount of water added during the wet granulation step is preferably between 1.5 and 5 times, especially between 1.75 and 3.5 times, the dry weight of the opioid.

The matrices of the present invention may also be prepared via a melt pelletization technique. In such circumstance, the opioid in finely divided form is combined with a binder (also in particulate form) and other optional inert ingredients, and thereafter the mixture is pelletized, e.g., by mechanically working the mixture in a high shear mixer to form the pellets (granules, spheres). Thereafter, the pellets (granules, spheres) may be sieved in order to obtain pellets of the requisite size. The binder material is preferably in particulate form and has a melting point above about 40° C. Suitable binder substances include, for example, hydrogenated castor oil, hydrogenated vegetable oil, other hydrogenated fats, fatty alcohols, fatty acid esters, fatty acid glycerides, and the like.

Controlled-release matrices can also be prepared by, e.g., melt-granulation or melt-extrusion techniques. Generally, melt-granulation techniques involve melting a normally solid hydrophobic binder material, e.g. a wax, and incorporating a powdered drug therein. To obtain a controlled release dosage form, it may be necessary to incorporate a hydrophobic controlled release material, e.g. ethylcellulose or a water-insoluble acrylic polymer, into the molten wax hydrophobic binder material. Examples of controlled-release formulations prepared via melt-granulation techniques are found, e.g., in U.S. Pat. No. 4,861,598, assigned to the Assignee of the present invention and hereby incorporated by reference in its entirety.

The additional hydrophobic binder material may comprise one or more water-insoluble wax-like thermoplastic substances possibly mixed with one or more wax-like thermoplastic substances being less hydrophobic than said one or more water-insoluble wax-like substances. In order to achieve controlled release, the individual wax-like substances in the formulation should be substantially non-degradable and insoluble in gastrointestinal fluids during the initial release phases. Useful water-insoluble wax-like binder substances may be those with a water-solubility that is lower than about 1:5,000 (w/w).

In addition to the above ingredients, a controlled release matrix may also contain suitable quantities of other materials, e.g., diluents, lubricants, binders, granulating aids, colorants, flavorants and glidants that are conventional in the pharmaceutical art in amounts up to about 50% by weight of the particulate if desired. The quantities of these additional materials will be sufficient to provide the desired effect to the desired formulation.

Specific examples of pharmaceutically acceptable carriers and excipients that may be used to formulate oral dosage forms are described in the Handbook of Pharmaceutical Excipients, American Pharmaceutical Association (1986), incorporated by reference herein.

The preparation of a suitable melt-extruded matrix according to the present invention may, for example, include the steps of blending the opioid analgesic, together with a controlled release material and preferably a binder material to obtain a homogeneous mixture. The homogeneous mixture is then heated to a temperature sufficient to at least soften the mixture sufficiently to extrude the same. The resulting homogeneous mixture is then extruded, e.g., using a twin-screw extruder, to form strands. The extrudate is preferably cooled and cut into multiparticulates by any means known in the art. The strands are cooled and cut into multiparticulates. The multiparticulates are then divided into unit doses. The extrudate preferably has a diameter of from about 0.1 to about 5 mm and provides controlled release of the therapeutically active agent for a time period of from about 8 to about 24 hours.

An optional process for preparing the melt extrusioned formulations of the present invention includes directly metering into an extruder a hydrophobic controlled release material, a therapeutically active agent, and an optional binder material; heating the homogenous mixture; extruding the homogenous mixture to thereby form strands; cooling the strands containing the homogeneous mixture; cutting the strands into particles having a size from about 0.1 mm to about 12 mm; and dividing said particles into unit doses. In this aspect of the invention, a relatively continuous manufacturing procedure is realized.

Plasticizers, such as those described hereinabove, may be included in melt-extruded matrices. The plasticizer is preferably included as from about 0.1 to about 30% by weight of the matrix. Other pharmaceutical excipients, e.g., talc, mono or poly saccharides, colorants, flavorants, lubricants and the like may be included in the controlled release matrices of the present invention as desired. The amounts included will depend upon the desired characteristic to be achieved.

The diameter of the extruder aperture or exit port can be adjusted to vary the thickness of the extruded strands. Furthermore, the exit part of the extruder need not be round; it can be oblong, rectangular, etc. The exiting strands can be reduced to particles using a hot wire cutter, guillotine, etc. A melt extruded multiparticulate system can be, for example, in the form of granules, spheroids or pellets depending upon the extruder exit orifice. For purposes of the present invention, the terms “melt-extruded multiparticulate(s)” and “melt-extruded multiparticulate system(s)” and “melt-extruded particles” shall refer to a plurality of units, preferably within a range of similar size and/or shape and containing one or more active agents and one or more excipients, preferably including a hydrophobic controlled release material as described herein. Preferably the melt-extruded multiparticulates will be of a range of from about 0.1 to about 12 mm in length and have a diameter of from about 0.1 to about 5 mm. In addition, it is to be understood that the melt-extruded multiparticulates can be any geometrical shape within this size range, such as, simply by way of example, beads, seeds, pellets, etc. Alternatively, the extrudate may simply be cut into desired lengths and divided into unit doses of the therapeutically active agent without the need of a spheronization step.

In one preferred embodiment, oral dosage forms are prepared that include an effective amount of melt-extruded multiparticulates within a capsule. For example, a plurality of the melt-extruded multiparticulates may be placed in a gelatin capsule in an amount sufficient to provide an effective controlled release dose when ingested and contacted by gastric fluid.

In another preferred embodiment, a suitable amount of the multiparticulate extrudate is compressed into an oral tablet using conventional tableting equipment using standard techniques. Techniques and compositions for making tablets (compressed and molded), capsules (hard and soft gelatin) and pills are also described in Remington's Pharmaceutical Sciences, (Arthur Osol, editor), 1553-1593 (1980), incorporated by reference herein.

In yet another preferred embodiment, the extrudate can be shaped into tablets as set forth in U.S. Pat. No. 4,957,681 (Klimesch, et. al.), described in additional detail above and hereby incorporated by reference.

Optionally, the controlled-release matrix multiparticulate systems or tablets can be coated, or the gelatin capsule can be further coated, with a controlled release coating such as the controlled release coatings described above. Such coatings preferably include a sufficient amount of hydrophobic and/or hydrophilic controlled-release material to obtain a weight gain level from about 2 to about 25 percent, although the overcoat may be greater depending upon, e.g., the physical properties of the particular opioid analgesic used and the desired release rate, among other things.

The dosage forms of the present invention may further include combinations of melt-extruded multiparticulates containing one or more opioid analgesics. Furthermore, the dosage forms can also include an amount of an immediate release therapeutically active agent for prompt therapeutic effect. The immediate release therapeutically active agent may be incorporated, e.g., as separate pellets within a gelatin capsule, or may be coated on the surface of, e.g., beads or melt extruded multiparticulates. The unit dosage forms of the present invention may also contain a combination of, e.g., controlled release beads and matrix multiparticulates to achieve a desired effect.

The controlled-release formulations of the present invention preferably slowly release the therapeutically active agent, e.g., when ingested and exposed to gastric fluids, and then to intestinal fluids. The controlled-release profile of the melt-extruded formulations of the invention can be altered, for example, by varying the amount of controlled-release material, by varying the amount of plasticizer relative to other matrix constituents, hydrophobic material, by the inclusion of additional ingredients or excipients, by altering the method of manufacture, etc.

In other embodiments of the invention, melt-extruded formulations are prepared without the inclusion of the therapeutically active agent, which is added thereafter to the extrudate. Such formulations typically will have the therapeutically active agent blended together with the extruded matrix material, and then the mixture would be tableted in order to provide a slow release formulation. Such formulations may be advantageous, for example, when the therapeutically active agent included in the formulation is sensitive to temperatures needed for softening the hydrophobic material and/or the retardant material.

Typical melt-extrusion production systems suitable for use in accordance with the present invention include a suitable extruder drive motor having variable speed and constant torque control, start-stop controls, and ammeter. In addition, the production system will include a temperature control console which includes temperature sensors, cooling means and temperature indicators throughout the length of the extruder. In addition, the production system will include an extruder such as twin-screw extruder which consists of two counter-rotating intermeshing screws enclosed within a cylinder or barrel having an aperture or die at the exit thereof. The feed materials enter through a feed hopper and are moved through the barrel by the screws and are forced through the die into strands which are thereafter conveyed such as by a continuous movable belt to allow for cooling and being directed to a pelletizer or other suitable device to render the extruded ropes into the multiparticulate system. The pelletizer can consist of rollers, fixed knife, rotating cutter and the like. Suitable instruments and systems are available from distributors such as C.W. Brabender Instruments, Inc. of South Hackensack, N.J. Other suitable apparatus will be apparent to those of ordinary skill in the art.

A further aspect of the invention is related to the preparation of melt-extruded multiparticulates as set forth above in a manner which controls the amount of air included in the extruded product. By controlling the amount of air included in the extrudate, it has been surprisingly found that the release rate of the therapeutically active agent from the, e.g., multiparticulate extrudate, can be altered significantly. In certain embodiments, it has been surprisingly found that the pH dependency of the extruded product can be altered as well.

Thus, in a further aspect of the invention, the melt-extruded product is prepared in a manner which substantially excludes air during the extrusion phase of the process. This may be accomplished, for example, by using a Leistritz extruder having a vacuum attachment. It has been surprisingly found that extruded multiparticulates prepared according to the invention using the Leistritz extruder under vacuum provides a melt-extruded product having different physical characteristics. In particular, the extrudate is substantially non-porous when magnified, e.g., using a scanning electron microscope which provides an SEM (scanning electron micrograph). Contrary to conventional thought, it has been found that such substantially non-porous formulations provide a faster release of the therapeutically active agent, relative to the same formulation prepared without vacuum. SEMs of the multiparticulates prepared using an extruder under vacuum appear very smooth, and the multiparticulates tend to be more robust than those multiparticulates prepared without vacuum. It has been observed that in at least certain formulations, the use of extrusion under vacuum provides an extruded multiparticulate product which is more pH-dependent than its counterpart formulation prepared without vacuum.

Controlled-release dosage forms according to the present invention may also be prepared as matrix beads formulations. The matrix beads include a spheronising agent and the hydrocodone.

The hydrocodone preferably comprises from about 0.01 to about 99% by weight of the matrix bead by weight. It is preferable that the hydrocodone is included as about 0.1 to about 50% by weight of the matrix bead.

Spheronising agents which may be used to prepare the matrix bead formulations of the present invention include any art-known spheronising agent. Cellulose derivatives are preferred, and microcrystalline cellulose is especially preferred. A suitable microcrystalline cellulose is, for example, the material sold as Avicel PH 101 (Trade Mark, FMC Corporation). The spheronising agent is preferably included as about 1 to about 99% of the matrix bead by weight.

In addition to the active ingredient and spheronizing agent, the spheroids may also contain a binder. Suitable binders, such as low viscosity, water soluble polymers, will be well known to those skilled in the pharmaceutical art. However, water soluble hydroxy lower alkylcellulose, such as hydroxypropylcellulose, are preferred.

In addition to the opioid analgesic and spheronising agent, the matrix bead formulations of the present invention may include a controlled release material such as those described hereinabove. Preferred controlled-release materials for inclusion in the matrix bead formulations include acrylic and methacrylic acid polymers or copolymers, and ethylcellulose. When present in the formulation, the controlled-release material will be included in amounts of from about 1 to about 80% of the matrix bead, by weight. The controlled-release material is preferably included in the matrix bead formulation in an amount effective to provide controlled release of the opioid analgesic from the bead.

Pharmaceutical processing aids such as binders, diluents, and the like may be included in the matrix bead formulations. Amounts of these agents included in the formulations will vary with the desired effect to be exhibited by the formulation.

The matrix beads may be overcoated with a controlled-release coating including a controlled-release material such as those described hereinabove. The controlled-release coating is applied to a weight gain of from about 5 to about 30%. The amount of the controlled-release coating to be applied will vary according to a variety of factors, e.g., the composition of the matrix bead and the chemical and/or physical properties of the opioid analgesic (i.e., hydrocodone).

Matrix beads are generally prepared by granulating the spheronising agent together with the opioid analgesic, e.g. by wet granulation. The granulate is then spheronized to produce the matrix beads. The matrix beads are then optionally overcoated with the controlled release coating by methods such as those described hereinabove.

Another method for preparing matrix beads, for example, by (a) forming granules comprising at least one water soluble hydroxyalkyl cellulose and opioid or an opioid salt; (b) mixing the hydroxyalkyl cellulose containing granules with at least one C12-C36 aliphatic alcohol; and (c) optionally, compressing and shaping the granules. Preferably, the granules are formed by wet granulating the hydroxyalkyl cellulose/opioid with water. In a particularly preferred embodiment of this process, the amount of water added during the wet granulation step is preferably between 1.5 and 5 times, especially between 1.75 and 3.5 times, the dry weight of the opioid.

In yet other alternative embodiments, a spheronizing agent, together with the active ingredient can be spheronized to form spheroids. Microcrystalline cellulose is preferred. A suitable microcrystalline cellulose is, for example, the material sold as Avicel PH 101 (Trade Mark, FMC Corporation). In such embodiments, in addition to the active ingredient and spheronizing agent, the spheroids may also contain a binder. Suitable binders, such as low viscosity, water soluble polymers, will be well known to those skilled in the pharmaceutical art. However, water soluble hydroxy lower alkyl cellulose, such as hydroxy propyl cellulose, are preferred. Additionally (or alternatively) the spheroids may contain a water insoluble polymer, especially an acrylic polymer, an acrylic copolymer, such as a methacrylic acid-ethyl acrylate copolymer, or ethyl cellulose. In such embodiments, the sustained-release coating will generally include a water insoluble material such as (a) a wax, either alone or in admixture with a fatty alcohol; or (b) shellac or zein.

In one especially preferred embodiment, the oral dosage form comprises an effective number of controlled release spheroids contained within a gelatin capsule.

In another preferred embodiment of the present invention, the controlled-release dosage form comprises spheroids containing the active ingredient coated with a controlled-release coating including a controlled release material. The term spheroid is known in the pharmaceutical art and means, e.g., a spherical granule having a diameter of between 0.1 mm and 2.5 mm, especially between 0.5 mm and 2 mm.

The spheroids are preferably film coated with a controlled release material that permits release of the opioid (or salt) at a controlled rate in an aqueous medium. The film coat is chosen so as to achieve, in combination with the other stated properties, the in-vitro release rate outlined above (e.g., at least about 12.5% released after 1 hour). The controlled-release coating formulations of the present invention preferably produce a strong, continuous film that is smooth and elegant, capable of supporting pigments and other coating additives, non-toxic, inert, and tack-free.

The dosage forms of the present invention may optionally be coated with one or more coatings suitable for the regulation of release or for the protection of the formulation. In one embodiment, coatings are provided to permit either pH-dependent or pH-independent release, e.g., when exposed to gastrointestinal fluid. When a pH-independent coating is desired, the coating is designed to achieve optimal release regardless of pH-changes in the environmental fluid, e.g., the GI tract. Other preferred embodiments include a pH-dependent coating that releases the opioid in desired areas of the gastro-intestinal (GI) tract, e.g., the stomach or small intestine, such that an absorption profile is provided which is capable of providing at least about twelve hour and preferably up to twenty-four hour analgesia to a patient. It is also possible to formulate compositions which release a portion of the dose in one desired area of the GI tract, e.g., the stomach, and release the remainder of the dose in another area of the GI tract, e.g., the small intestine.

Formulations according to the invention that utilize pH-dependent coatings may also impart a repeat-action effect whereby unprotected drug is coated over an enteric coat and is released in the stomach, while the remainder, being protected by the enteric coating, is released further down the gastrointestinal tract. Coatings which are pH-dependent may be used in accordance with the present invention include a controlled release material such as, e.g., shellac, cellulose acetate phthalate (CAP), polyvinyl acetate phthalate (PVAP), hydroxypropyl methylcellulose phthalate, and methacrylic acid ester copolymers, zein, and the like.

In another preferred embodiment, the present invention is related to a stabilized solid controlled dosage form comprising an opioid coated with a hydrophobic controlled release material selected from (i) an alkylcellulose; (ii) an acrylic polymer; or (iii) mixtures thereof. The coating may be applied in the form of an organic or aqueous solution or dispersion.

In certain preferred embodiments, the controlled release coating is derived from an aqueous dispersion of the hydrophobic controlled release material. The coated substrate containing the opioid(s) (e.g., a tablet core or inert pharmaceutical beads or spheroids) is then cured until an endpoint is reached at which the substrate provides a stable dissolution. The curing endpoint may be determined by comparing the dissolution profile (curve) of the dosage form immediately after curing to the dissolution profile (curve) of the dosage form after exposure to accelerated storage conditions of, e.g., at least one month at a temperature of 40° C. and a relative humidity of 75%. These formulations are described in detail in U.S. Pat. Nos. 5,273,760 and 5,286,493, assigned to the Assignee of the present invention and hereby incorporated by reference. Other examples of controlled-release formulations and coatings which may be used in accordance with the present invention include Assignee's U.S. Pat. Nos. 5,324,351; 5,356,467, and 5,472,712, hereby incorporated by reference in their entirety.

In preferred embodiments, the controlled release coatings include a plasticizer such as those described herein below.

In certain embodiments, it is necessary to overcoat the substrate comprising the opioid analgesic with a sufficient amount of the aqueous dispersion of e.g., alkylcellulose or acrylic polymer, to obtain a weight gain level from about 2 to about 50%, e.g., about 2 to about 25% in order to obtain a controlled-release formulation. The overcoat may be lesser or greater depending upon the physical properties of the therapeutically active agent and the desired release rate, the inclusion of plasticizer in the aqueous dispersion and the manner of incorporation of the same, for example.

Cellulosic materials and polymers, including alkylcelluloses are controlled release materials well suited for coating the substrates, e.g., beads, tablets, etc. according to the invention. Simply by way of example, one preferred alkylcellulosic polymer is ethylcellulose, although the artisan will appreciate that other cellulose and/or alkylcellulose polymers may be readily employed, singly or on any combination, as all or part of a hydrophobic coatings according to the invention.

One commercially-available aqueous dispersion of ethylcellulose is Aquacoat® (FMC Corp., Philadelphia, Pa., U.S.A.). Aquacoat® is prepared by dissolving the ethylcellulose in a water-immiscible organic solvent and then emulsifying the same in water in the presence of a surfactant and a stabilizer. After homogenization to generate submicron droplets, the organic solvent is evaporated under vacuum to form a pseudolatex. The plasticizer is not incorporated in the pseudolatex during the manufacturing phase. Thus, prior to using the same as a coating, it is necessary to intimately mix the Aquacoat® with a suitable plasticizer prior to use.

Another aqueous dispersion of ethylcellulose is commercially available as Surelease® (Colorcon, Inc., West Point, Pa., U.S.A.). This product is prepared by incorporating plasticizer into the dispersion during the manufacturing process. A hot melt of a polymer, plasticizer (dibutyl sebacate), and stabilizer (oleic acid) is prepared as a homogeneous mixture, which is then diluted with an alkaline solution to obtain an aqueous dispersion which can be applied directly onto substrates.

In other preferred embodiments of the present invention, the controlled release material comprising the controlled-release coating is a pharmaceutically acceptable acrylic polymer, including but not limited to acrylic acid and methacrylic acid copolymers, methyl methacrylate copolymers, ethoxyethyl methacrylates, cynaoethyl methacrylate, poly(acrylic acid), poly(methacrylic acid), methacrylic acid alkylamide copolymer, poly(methyl methacrylate), polymethacrylate, poly(methyl methacrylate) copolymer, polyacrylamide, aminoalkyl methacrylate copolymer, poly(methacrylic acid anhydride), and glycidyl methacrylate co-polymers.

In certain preferred embodiments, the acrylic polymer is comprised of one or more ammonia methacrylate copolymers. Ammonia methacrylate copolymers are well known in the art, and are described in NF XVII as fully polymerized copolymers of acrylic and methacrylic acid esters with a low content of quaternary ammonium groups.

In order to obtain a desirable dissolution profile, it may be necessary to incorporate two or more ammonia methacrylate copolymers having differing physical properties, such as different molar ratios of the quaternary ammonium groups to the neutral (meth)acrylic esters.

Certain methacrylic acid ester-type polymers are useful for preparing pH-dependent coatings which may be used in accordance with the present invention. For example, there are a family of copolymers synthesized from diethylaminoethyl methacrylate and other neutral methacrylic esters, also known as methacrylic acid copolymer or polymeric methacrylates, commercially available as Eudragit® from Röhm Tech, Inc. There are several different types of Eudragit®. For example, Eudragit E is an example of a methacrylic acid copolymer which swells and dissolves in acidic media. Eudragit L is a methacrylic acid copolymer which does not swell at about pH<5.7 and is soluble at about pH>6. Eudragit S does not swell at about pH<6.5 and is soluble at about pH>7. Eudragit RL and Eudragit RS are water swellable, and the amount of water absorbed by these polymers is pH-dependent, however, dosage forms coated with Eudragit RL and RS are pH-independent.

In certain preferred embodiments, the acrylic coating comprises a mixture of two acrylic resin lacquers commercially available from Rohm Pharma under the Tradenames Eudragit® RL30D and Eudragit® RS30D, respectively. Eudragit® RL30D and Eudragit® RS30D are copolymers of acrylic and methacrylic esters with a low content of quaternary ammonium groups, the molar ratio of ammonium groups to the remaining neutral (meth)acrylic esters being 1:20 in Eudragit® RL30D and 1:40 in Eudragit® RS30D. The mean molecular weight is about 150,000. The code designations RL (high permeability) and RS (low permeability) refer to the permeability properties of these agents. Eudragit® RL/RS mixtures are insoluble in water and in digestive fluids. However, coatings formed from the same are swellable and permeable in aqueous solutions and digestive fluids.

The Eudragit® RL/RS dispersions of the present invention may be mixed together in any desired ratio in order to ultimately obtain a controlled-release formulation having a desirable dissolution profile. Desirable controlled-release formulations may be obtained, for instance, from a retardant coating derived from 100% Eudragit® RL, 50% Eudragit® RL and 50% Eudragit® RS, and 10% Eudragit® RL:Eudragit® 90% RS. Of course, one skilled in the art will recognize that other acrylic polymers may also be used, such as, for example, Eudragit® L.

In embodiments of the present invention where the coating comprises an aqueous dispersion of a hydrophobic controlled release material, the inclusion of an effective amount of a plasticizer in the aqueous dispersion of hydrophobic material will further improve the physical properties of the controlled-release coating. For example, because ethylcellulose has a relatively high glass transition temperature and does not form flexible films under normal coating conditions, it is preferable to incorporate a plasticizer into an ethylcellulose coating containing controlled-release coating before using the same as a coating material. Generally, the amount of plasticizer included in a coating solution is based on the concentration of the film-former, e.g., most often from about 1 to about 50 percent by weight of the film-former. Concentration of the plasticizer, however, can only be properly determined after careful experimentation with the particular coating solution and method of application.

Examples of suitable plasticizers for ethylcellulose include water insoluble plasticizers such as dibutyl sebacate, diethyl phthalate, triethyl citrate, tibutyl citrate, and triacetin, although it is possible that other water-insoluble plasticizers (such as acetylated monoglycerides, phthalate esters, castor oil, etc.) may be used. Triethyl citrate is an especially preferred plasticizer for the aqueous dispersions of ethyl cellulose of the present invention.

Examples of suitable plasticizers for the acrylic polymers of the present invention include, but are not limited to citric acid esters such as triethyl citrate NF XVI, tributyl citrate, dibutyl phthalate, and possibly 1,2-propylene glycol. Other plasticizers which have proved to be suitable for enhancing the elasticity of the films formed from acrylic films such as Eudragit® RL/RS lacquer solutions include polyethylene glycols, propylene glycol, diethyl phthalate, castor oil, and triacetin. Triethyl citrate is an especially preferred plasticizer for the aqueous dispersions of ethyl cellulose of the present invention.

It has further been found that the addition of a small amount of talc to the controlled release coating reduces the tendency of the aqueous dispersion to stick during processing, and acts as a polishing agent.

When an aqueous dispersion of hydrophobic material is used to coat substrates, e.g., inert pharmaceutical beads such as no pariel 18/20 beads, a plurality of the resultant stabilized solid controlled-release beads may thereafter be placed in a gelatin capsule in an amount sufficient to provide an effective controlled-release dose when ingested and contacted by an environmental fluid, e.g., gastric fluid or dissolution media.

The stabilized controlled-release bead formulations of the present invention slowly release the opioid analgesic, e.g., when ingested and exposed to gastric fluids, and then to intestinal fluids. The controlled-release profile of the formulations of the invention can be altered, for example, by varying the amount of overcoating with the aqueous dispersion of hydrophobic controlled release material, altering the manner in which the plasticizer is added to the aqueous dispersion of hydrophobic controlled release material, by varying the amount of plasticizer relative to hydrophobic controlled release material, by the inclusion of additional ingredients or excipients, by altering the method of manufacture, etc. The dissolution profile of the ultimate product may also be modified, for example, by increasing or decreasing the thickness of the controlled release coating.

Substrates coated with a therapeutically active agent are prepared, e.g. by dissolving the therapeutically active agent in water and then spraying the solution onto a substrate, for example, no pariel 18/20 beads, using a Wuster insert. Optionally, additional ingredients are also added prior to coating the beads in order to assist the binding of the opioid to the beads, and/or to color the solution, etc. For example, a product which includes hydroxypropyl methylcellulose, etc. with or without colorant (e.g., Opadry®, commercially available from Colorcon, Inc.) may be added to the solution and the solution mixed (e.g., for about 1 hour) prior to application of the same onto the substrate. The resultant coated substrate may then be optionally overcoated with a barrier agent, to separate the therapeutically active agent from the hydrophobic controlled-release coating.

An example of a suitable barrier agent is one which comprises hydroxypropyl methylcellulose. However, any film-former known in the art may be used. It is preferred that the barrier agent does not affect the dissolution rate of the final product.

The substrates may then be overcoated with an aqueous dispersion of the hydrophobic controlled release material. The aqueous dispersion of hydrophobic controlled release material preferably further includes an effective amount of plasticizer, e.g. triethyl citrate. Pre-formulated aqueous dispersions of ethylcellulose, such as Aquacoat® or Surelease®, may be used. If Surelease® is used, it is not necessary to separately add a plasticizer. Alternatively, pre-formulated aqueous dispersions of acrylic polymers such as Eudragit® can be used.

The coating solutions of the present invention preferably contain, in addition to the film-former, plasticizer, and solvent system (i.e., water), a colorant to provide elegance and product distinction. Color may be added to the solution of the therapeutically active agent instead, or in addition to the aqueous dispersion of hydrophobic material. For example, color can be added to Aquacoat® via the use of alcohol or propylene glycol based color dispersions, milled aluminum lakes and opacifiers such as titanium dioxide by adding color with shear to water soluble polymer solution and then using low shear to the plasticized Aquacoat®. Alternatively, any suitable method of providing color to the formulations of the present invention may be used. Suitable ingredients for providing color to the formulation when an aqueous dispersion of an acrylic polymer is used include titanium dioxide and color pigments, such as iron oxide pigments. The incorporation of pigments, may, however, increase the retard effect of the coating.

The plasticized aqueous dispersion of hydrophobic controlled release material may be applied onto the substrate comprising the therapeutically active agent by spraying using any suitable spray equipment known in the art. In a preferred method, a Wurster fluidized-bed system is used in which an air jet, injected from underneath, fluidizes the core material and effects drying while the acrylic polymer coating is sprayed on. A sufficient amount of the aqueous dispersion of hydrophobic material to obtain a predetermined controlled-release of said therapeutically active agent when said coated substrate is exposed to aqueous solutions, e.g. gastric fluid, is preferably applied, taking into account the physical characteristics of the therapeutically active agent, the manner of incorporation of the plasticizer, etc. After coating with the hydrophobic controlled release material, a further overcoat of a film-former, such as Opadry®, is optionally applied to the beads. This overcoat is provided, if at all, in order to substantially reduce agglomeration of the beads.

The release of the therapeutically active agent from the controlled-release formulation of the present invention can be further influenced, i.e., adjusted to a desired rate, by the addition of one or more release-modifying agents, or by providing one or more passageways through the coating. The ratio of hydrophobic controlled release material to water soluble material is determined by, among other factors, the release rate required and the solubility characteristics of the materials selected.

The release-modifying agents which function as pore-formers may be organic or inorganic, and include materials that can be dissolved, extracted or leached from the coating in the environment of use. The pore-formers may comprise one or more hydrophilic materials such as hydroxypropylmethylcellulose.

The controlled-release coatings of the present invention can also include erosion-promoting agents such as starch and gums.

The controlled-release coatings of the present invention can also include materials useful for making microporous lamina in the environment of use, such as polycarbonates comprised of linear polyesters of carbonic acid in which carbonate groups reoccur in the polymer chain.

The release-modifying agent may also comprise a semi-permeable polymer. In certain preferred embodiments, the release-modifying agent is selected from hydroxypropylmethylcellulose, lactose, metal stearates, and mixtures of any of the foregoing.

The controlled-release coatings of the present invention may also include an exit means comprising at least one passageway, orifice, or the like. The passageway may be formed by such methods as those disclosed in U.S. Pat. Nos. 3,845,770; 3,916,889; 4,063,064; and 4,088,864, all of which are hereby incorporated by reference. The passageway can have any shape such as round, triangular, square, elliptical, irregular, etc.

Another method of producing controlled release bead formulations suitable for about 24-hour administration is via powder layering. U.S. Pat. No. 5,411,745, assigned to the Assignee of the present invention and hereby incorporated by reference in its entirety, teaches preparation of 24-hour morphine formulations prepared via powder layering techniques utilizing a processing aid consisting essentially of hydrous lactose impalpable. The powder-layered beads are prepared by spraying an aqueous binder solution onto inert beads to provide a tacky surface, and subsequently spraying a powder that is a homogenous mixture of morphine sulfate and hydrous lactose impalpable onto the tacky beads. The beads are then dried and coated with a hydrophobic material such as those described hereinabove to obtain the desired release of drug when the final formulation is exposed to environmental fluids. An appropriate amount of the controlled release beads are then, e.g. encapsulated to provide a final dosage form which provides effective plasma concentrations of morphine for about 12 hours.

The following examples illustrate various aspects of the present invention. They are not meant to be construed to limit the claims in any manner whatsoever.

Hydrocodone sustained release tablets were produced with the formula set forth in Table 1 below:

TABLE 1
Ingredients Amt/Unit (mg) Amount/Batch (gm)
Hydrocodone Bitartrate 15.0 150.0
Spray Dried Lactose 56.0 560.0
Povidone 4.0 40.0
Eudragit RS30D (solids) 10.0 100.0
Triacetin 2.0 20.0
Stearyl Alcohol 20.0 200.0
Talc 2.0 20.0
Magnesium Stearate 1.0 10.0
Total 110.0 1100.0

According to the following procedure:

The tablets were then tested for dissolution using the following procedure:

The dissolution parameters are set forth in Table II below:

TABLE II
Time (Hours) % Dissolved
1 39.7
2 51.5
4 67.4
8 86.4
12 96.1

The Cmax and Tmax were then obtained for Example 1 and an immediate release reference standard in a bioavailability study comparing hydrocodone 15 mg administered as an immediate release formulation (Lortab 7.5 mg×2) to the above CR formulation in healthy human subjects, as set forth in Table III below:

TABLE III
Pharmacokinetic data Hydrocodone Bitartrate
Cmax (ng/ml) 35.4
IR reference product
Cmax (ng/ml) 13.4
CR product
Cmax (CR)/Cmax (IR) 38%
Tmax (hr) 1.32
IR reference product
Tmax(hr) 4.07
CR product

Hydrocodone sustained release tablets were produced with the formula set forth in Table IV below:

TABLE IV
Ingredients Amt/Unit (mg) Amt/Batch (g)
Hydrocodone Bitartrate 15.0 150.0
Spray Dried Lactose 51.0 510.0
Povidone 4.0 40.0
Eudragit RS30D 10.0 100.0
(solids)
Triacetin 2.0 20.0
Stearyl Alcohol 25.0 250.0
Talc 2.0 20.0
Magnesium Stearate 1.0 10.0
Total 110.0 1100.0

according to the procedure of Example 1.

The dissolution parameters were then obtained using the procedure of Example 1. The results are set forth in table V below:

TABLE V
Time (Hours) % Dissolved
1 36
2 45.8
4 60.5
8 78.9
12 90.4

Hydrocodone sustained release capsules were produced with the formula set forth in Table VI below:

TABLE VI
Ingredients Amt/Unit (mg) Amt/Batch (g)
Hydrocodone 15.0 320.0
Bitartrate
Eudragit RSPO 76.0 1520.0
Eudragit RLPO 4.0 80.0
Stearyl Alcohol 25.0 500.0
Total 120.0 2400.0

According to the following procedure:

Zone 1  10° C.
Zone 2  20° C.
Zone 3 120° C.
Zone 4 120° C.
Zone 5 120° C.
Zone 6 120° C.
Zone 7  95° C.
Zone 8  95° C.
MGA 120° C.
Die 117° C.

Powder feed rate—40 g/min; screw speed—185 rpm; vacuum—˜980 mBar
Conveyor-such that diameter of extrudate is 1 mm
Pelletizer-such that pellets are cut to 1 mm in length

The dissolution parameters were then obtained using the procedure of Example 1. The results are set forth in table VII below:

TABLE VII
Time (Hours) % Dissolved
1 23.9
2 34.7
4 51.7
8 74.6
12 85.2

Oxycodone sustained release tablets were produced with the formula set forth in Table VIII below:

TABLE VIII
Ingredients Amt/Unit (mg) Amount/Batch (gm)
Oxycodone HCl 20.0 22.0
Spray Dried Lactose 59.25 65.175
Povidone 5.0 5.5
Eudragit RS30D (solids) 10.0 11.0
Triacetin 2.0 2.2
Stearyl Alcohol 25.0 27.5
Talc 2.5 2.75
Magnesium Stearate 1.25 1.375
Opadry Pink Y-S-14518A 4.0 4.26
Total 129.0 141.76

According to the following procedure:

The tablets were then tested for dissolution using the following procedure:

The dissolution parameters are set forth in Table IX below:

TABLE IX
Time (hrs) % Dissolved
1 45
2 55
4 70
8 87
12 96
18 101
24 102

The Cmax and Tmax were then obtained for Example 4 and an immediate release reference standard in a bioavailability study, as set forth in Table X below:

TABLE X
Pharmacokinetic data Oxycodone HCl
Cmax (ng/ml) 38.2
IR reference product
Cmax (ng/ml) 21.7
CR product
Cmax (CR)/Cmax (IR) 57%
Tmax (hr) 1.10
IR reference product
Tmax(hr) 2.62
CR product

Morphine sustained release tablets were produced with the formula set forth in Table XI below:

TABLE XI
Ingredients Amount/unit (mg) Amount/batch (kg)
Morphine sulfate 30.0 138.0
Spray Dried Lactose 70.0 322.0
Hydroxyethyl cellulose 10.0 46.0
Cetostearyl alcohol 35.0 161.0
Talc 3.0 13.8
Magnesium stearate 2.0 9.2
Opadry YS-1-4729 5.0 23.0
To0tal 155.0 713.0

According to the following procedure:

The tablets were then tested for dissolution using the following procedure:

The dissolution parameters are set forth in Table XII below:

TABLE XII
Time (Hours) % Dissolved
1 34.2
2 49.9
3 64.2
4 75.5
6 90.3

The Cmax and Tmax were then obtained for Example 5 and an immediate release reference standard in a bioavailability study, as set forth in Table XIII below:

TABLE XIII
Pharmacokinetic data Morphine Sulphate
Cmax (ng/ml) 22.1
IR reference product
Cmax (ng/ml) 12
CR product
Cmax (CR)/Cmax (IR) 54%
Tmax (hr) 0.98
IR reference product
Tmax(hr) 2.09
CR product

The pharmakokinetic parameters of Example 1, Example 4 and Example 5 were compared to each other. It was surprisingly found that even though the dissolution of the hydrocodone HCl controlled release tablets of example 1 were very similar to the dissolution of the controlled release oxycodone tablets of example 4 and the morphine sulfate controlled release tablets of example 5, the Cmax ratio of CR to IR for the hydrocodone formulation is 38%, whereas the oxycodone tablets and morphine tablets are over 50%. The comparative results are set forth in Table XIV below:

TABLE XIV
Hydrocodone Oxycodone Morphine
Pharmacokinetic data Bitartrate HCl Sulphate
Cmax (ng/ml) 35.4 38.2 22.1
IR reference product
Cmax (ng/ml) 13.4 21.7 12
CR product
Cmax (CR)/Cmax (IR) 38% 57% 54%
Tmax (hr) 1.32 1.10 0.98
IR reference product
Tmax(hr) 4.07 2.62 2.09
CR product

A single dose, four treatment, open label, pharmacokinetic comparison of controlled release hydrocodone formulations of Example 1, Example 2, Example 3 and two immediate release hydrocodone bitartrate 7.5 mg/Acetaminophen 500 mg tablets (IR Example) in fasted normal volunteers was conducted. The plasma concentrations for these formulations are set forth in tables 15-18 below:

TABLE 15
Hydrocodone Plasma Concentration (ng/mL) after administration of one (1)
Controlled-Release Hydrocodone Bitartrate 15 mg tablet-Formulation A
Time (hours)
Subject −0.08 0.5 0.75 1 2 3 4 6 9 12 18 24 30 36
1 0.00 4.55 11.1 9.11 15.8 15.5 17.4 15.4 14.5 12.1 6.33 3.58 2.25 1.29
2 0.00 7.81 8.76 9.20 11.3 14.8 15.5 14.5 10.5 9.30 5.40 3.39 2.10 0.921
3 0.00 4.63 7.66 8.95 15.9 15.6 16.9 16.3 12.3 9.41 6.55 4.10 2.38 0.986
4 0.00 3.48 9.48 9.11 10.7 11.9 13.0 12.4 10.7 8.96 5.22 3.08 1.56 0.558
5 0.00 1.43 4.25 7.20 12.8 13.5 13.0 12.5 9.62 7.01 4.38 3.26 1.93 1.01
6 0.00 4.69 7.60 10.5 12.8 13.9 13.3 15.1 12.3 8.59 4.52 3.11 1.59 0.702
7 0.00 0.56 1.86 3.85 7.54 8.26 8.18 8.90 6.23 4.56 2.99 1.61 0.752 0.00
8 0.00 3.68 7.61 11.5 12.4 13.2 12.7 12.5 9.10 7.09 4.33 2.93 1.24 0.509
9 0.00 8.06 9.79 9.98 11.4 10.7 11.4 11.9 7.66 5.98 3.85 2.10 1.12 0.573
10  0.00 3.83 5.71 7.84 8.49 10.8 11.6 11.5 8.02 6.70 3.34 2.33 1.31 0.00
11  0.00 3.64 5.20 8.00 10.3 11.8 12.5 10.8 7.44 7.84 4.75 2.21 1.11 0.00
12  0.00 3.07 6.14 8.51 14.3 15.0 14.9 14.7 12.1 7.75 4.34 2.52 1.69 0.859
13  0.00 1.95 3.82 4.47 9.55 9.15 8.31 8.05 5.85 3.93 2.45 7.68 1.35 1.07
14  0.00 2.21 4.56 7.33 11.2 12.9 13.3 13.2 10.6 8.41 4.68 3.11 2.35 0.978
MEAN 0.00 3.83 6.68 8.25 11.7 12.6 13.0 12.7 9.78 7.69 4.51 3.22 1.62 0.675
SD 0.00 2.13 2.62 2.10 2.48 2.31 2.70 2.41 2.54 2.09 1.15 1.44 0.513 0.425
% CV 0.00 21.7 39.2 25.5 21.2 18.3 20.8 19.0 26.0 27.2 25.5 44.7 31.7 63.0

TABLE 16
Hydrocodone Plasma Concentration (ng/mL) after administration of one (1)
Controlled-Release Hydrocodone Bitartrate 15 mg tablet-Formulation B
Time (hours)
Subject −0.08 0.5 0.75 1 2 3 4 6 9 12 18 24 30 36
1 0.00 3.18 5.64 11.8 11.4 12.4 13.5 14.3 11.4 9.28 5.69 3.23 2.23 1.10
2 0.00 2.61 7.04 8.53 10.7 12.4 11.5 13.6 11.4 9.25 6.43 4.13 2.59 1.35
3 0.00 5.49 7.57 9.67 13.5 15.6 15.7 14.4 12.6 9.41 7.83 5.19 3.45 1.77
4 0.00 2.71 5.67 6.35 8.88 11.3 13.7 12.0 8.72 8.18 5.58 4.33 2.63 1.26
5 0.00 3.98 6.59 7.38 10.6 11.8 11.6 9.42 6.75 4.81 5.28 3.67 2.43 1.25
6 0.00 0.711 2.85 7.98 12.9 13.6 13 13.8 10.1 8.04 5.17 3.71 2.33 0.940
7 0.00 1.82 3.03 3.97 7.22 8.04 8.05 7.87 5.97 3.77 2.53 2.12 1.94 1.19
8 0.00 2.47 3.99 6.03 10.9 13.2 13.8 12.6 9.49 7.60 6.11 4.74 2.38 0.856
9 0.00 5.02 10.4 8.48 9.06 9.90 9.88 7.96 4.78 3.99 3.77 3.42 1.53 0.805
10  0.00 3.20 8.17 10.7 9.08 10.7 11.8 11.2 9.08 6.20 3.38 2.75 1.84 0.672
11  0.00 4.20 6.86 6.36 9.97 11.3 11.3 10.2 7.79 5.08 4.38 2.67 1.53 0.815
12  0.00 4.73 7.71 9.48 11.9 15.1 16.5 15.5 13.2 8.89 4.58 3.60 2.67 2.12
13  0.00 1.56 2.87 3.89 6.31 7.43 7.87 7.64 7.01 5.34 3.57 2.12 1.35 1.41
14  0.00 0.663 2.20 3.86 8.74 14.7 15.0 15.3 13.6 10.7 6.84 4.47 2.39 1.59
MEAN 0 3.02 5.76 7.46 10.1 12 12.4 11.8 9.42 7.18 5.08 3.58 2.24 1.22
SD 0 1.53 2.45 2.53 2.03 2.45 2.61 2.81 2.77 2.27 1.48 0.943 0.556 0.408
% CV 0 50.7 42.5 33.9 20.1 20.4 21 23.8 29.4 31.6 29.1 26.3 24.8 33.4

TABLE 17
Hydrocodone Plasma Concentration (ng/mL) after administration of two (2)
Immediate-Release Hydrocodone 7.5 mg/Acetaminophen 500 mg tablets-Formulation C
Time (hours)
Subject −0.08 0.5 0.75 1 2 3 4 6 9 12 18 24 30 36
1 0.00 40.6 41.6 45.4 32.1 26.3 22.7 15.2 9.95 6.08 2.58 1.20 0.585 0.00
2 0.00 44.3 50.7 40.1 28.6 23.3 20.2 15.6 9.46 6.08 2.96 1.68 0.872 0.00
3 0.00 17.6 42.3 42.6 37.8 35.4 31.2 21.0 13.0 7.79 3.12 1.77 0.685 0.00
4 0.00 21.2 43.3 36.5 26.9 23.5 20.7 15.4 9.39 5.09 2.27 1.17 0.523 0.00
5 0.00 37.4 39.3 36.1 27.9 22.4 18.1 14.1 7.91 4.98 2.37 1.07 0.546 0.00
6 0.00 3.17 8.67 16.3 17.5 16.9 13.8 11.3 6.52 4.22 1.71 0.703 0.00 0.00
7 0.00 0.900 6.76 14.7 18.3 17.1 14.1 9.66 5.52 3.32 1.21 0.00 0.00 0.00
8 0.00 2.97 13.7 22.2 32.4 28.8 24.2 18.3 10.9 6.46 2.17 1.02 0.00 0.00
9 0.00 50.0 39.3 33.7 24.2 20.1 17.0 13.0 6.84 4.01 1.47 0.585 0.00 0.00
10  0.00 0.627 14.8 25.2 22.4 17.3 16.5 10.9 5.90 3.15 1.05 0.00 0.00 0.00
11  0.00 8.46 13.3 29.3 31.3 24.8 21.0 14.0 9.43 6.04 2.62 1.14 0.00 0.00
12  0.00 30.6 44.4 44.4 40.0 30.8 29.1 19.9 11.3 6.86 3.15 1.47 0.634 0.00
13  0.00 3.73 12.2 17.9 19.1 19.8 16.3 13.9 8.72 5.43 2.51 0.706 0.00 0.00
14  0.00 18.0 29.7 35.3 30.7 26.6 23.4 16.1 9.20 6.24 2.60 1.27 0.556 0.00
MEAN 0.00 20.0 28.6 31.4 27.8 23.8 20.6 14.9 8.86 5.41 2.27 0.983 0.314 0.00
SD 0.00 17.7 16.0 10.6 6.93 5.48 5.21 3.26 2.15 1.36 0.676 0.541 0.336 0.00
% CV 0.00 88.5 55.9 33.8 24.9 23.0 25.3 21.9 24.3 25.1 29.8 55.0 107 0.00

TABLE 18
Hydrocodone Plasma Concentration (ng/mL) after administration of one (1)
Controlled-Release Hydrocodone Bitartrate 15 mg capsule-Formulation D
Time (hours)
Subject −0.08 0.5 0.75 1 2 3 4 6 9 12 18 24 30 36
1 0.00 1.76 4.07 5.17 8.33 9.72 11.1 14.0 13.6 11.7 8.78 6.14 3.91 1.97
2 0.00 2.76 4.83 5.13 6.17 10.4 10.6 13.5 11.8 10.1 6.57 3.71 2.57 1.34
3 0.00 2.91 4.25 6.01 10.1 12.3 12.0 14.8 13.5 11.4 7.40 4.16 2.65 1.46
4 0.00 1.69 5.93 6.26 8.29 8.37 8.06 10.5 8.91 8.70 4.58 2.61 1.63 0.536
5 0.00 0.616 2.74 4.47 8.58 9.16 8.60 10.1 8.66 6.64 4.72 2.57 2.05 0.986
6 0.00 0.663 2.40 4.87 7.50 10.1 11.7 13.0 11.5 8.30 5.38 3.88 2.39 1.25
7 0.00 0.00 1.55 2.32 4.61 6.38 7.22 7.41 6.75 4.82 3.10 1.72 0.984 0.578
8 0.00 1.26 3.03 5.15 7.26 8.80 8.81 9.34 9.07 9.28 6.81 3.31 1.93 1.25
9 0.00 3.36 3.63 6.38 8.31 8.04 8.20 9.55 8.28 6.49 3.72 2.25 1.92 0.901
10  0.00 0.692 2.91 2.95 5.11 6.09 7.37 7.11 6.33 5.67 3.76 2.76 1.43 0.573
11  0.00 1.11 2.87 3.28 6.82 9.69 10.3 12.0 12.2 8.81 5.76 3.25 2.10 1.08
12  0.00 2.25 3.31 4.72 8.03 11.4 11.2 12.1 11.0 9.75 5.64 3.51 2.71 1.34
13  0.00 0.00 1.29 2.71 5.51 6.67 8.92 8.44 7.13 7.01 3.99 2.41 1.04 0.858
14  0.00 1.02 2.94 4.53 8.82 10.5 11.7 14.1 13.0 10.2 6.37 3.56 1.93 1.61
MEAN 0.00 1.44 3.27 4.57 7.39 9.12 9.70 11.1 10.1 8.49 5.47 3.27 2.09 1.12
SD 0.00 1.06 1.23 1.31 1.57 1.86 1.71 2.57 2.55 2.11 1.61 1.08 0.754 0.419
% CV 0.00 73.6 37.6 28.7 21.2 20.4 17.6 23.2 25.2 24.9 29.4 33.0 36.1 37.4

The pharmacokinetic parameters are set forth in Table 19 below:

TABLE 19
Meana % Ratiob,c
Ex. 1 IR Ex. Ex. 1/IR Ex. 90% Clb
Parameter Fasted Fasted Fasted Lower Upper
AUC (0, last) 200.95 216.35 93.36 86.96 100.23
(ng · hr/mL)
Cmax (ng/mL) 13.16 33.37 39.48 35.26 44.20
Tmax (hr) 4.07 1.32 208.11 257.17 357.80
W50 (hr) 13.41 4.67 287.38 265.91 314.15
T½ (abs) (hr) 1.64 0.69 237.65 197.73 284.44
T½ (elim) (hr) 6.44 3.09 208.78 184.43 234.20
Ex. 2 IR Ex. Ex. 2/IR Ex.
Fasted Fasted Fasted Lower Upper
AUC (0, last) 201.57 216.35 93.21 86.82 100.07
(ng · hr/mL)
Cmax (ng/mL) 12.42 33.37 37.36 33.37 41.83
Tmax (hr) 4.20 1.32 317.57 262.19 362.83
W50 (hr) 13.08 4.67 280.31 257.03 305.26
T½ (abs) (hr) 1.57 0.69 227.91 183.84 270.55
T½ (elim) (hr) 7.86 3.09 254.85 231.54 281.31
Ex. 3 IR. Ex. Ex. 3/IR Ex.
Fasted Fasted Fasted Lower Upper
AUC (0, last) 194.40 216.35 90.28 84.09 96.92
(ng · hr/mL)
Cmax (ng/mL) 10.93 33.37 32.69 29.20 36.60
Tmax (hr) 5.93 1.32 448.65 398.87 499.51
W50 (hr) 16.30 4.67 349.21 328.68 376.92
T½ (abs) (hr) 2.98 0.69 431.26 395.95 482.67
T½ (elim) (hr) 6.96 3.09 225.61 200.49 250.26
aGeometric means for AUC(0, last) and Cmax and arithmetic means for Tmax, W50, T½ (abs), and T½ (elim).
bRatio and 90% Cl are based on least square means.
cRatio (%): (Test mean/Reference mean) × 100, based on least square means

Hydrocodone sustained release tablets were produced with the formula set forth in Table XX below:

TABLE XX
Ingredient mg/tab kg/batch
Hydrocodone bitartrate 15 15.0
Dibasic calcium phosphate 31 31.0
Glyceryl behenate 10 10.0
Stearyl alcohol 22 22.0
Microcrystalline cellulose 31 31.0
Magnesium stearate 1.0 1.0
Opadry Purple YS-1-10371-A 5.0 5.0
Purified water N/A1 28.331
115.0 mg 115.0 kg
1Evaporates during processing and is not part of finished product.

According to the following procedure:

The tablets were then tested for dissolution using the following procedure:

The dissolution parameters are set forth in Table XXI below:

TABLE XXI
Time (hrs) % Dissolved
1 22
2 37
4 58
8 84
12 99

A 3 way crossover, pharmacokinetic comparison study of a single dose of 15 mg Hydrocodone Controlled Release Tablets (Example 8) in Fed and Fasted and of 15 mg Hydrocodone Immediate Release (2×7.5 mg tablets) was given over two Q6H doses in fasted normal volunteers.

The Cmax and Tmax were then obtained for Example 8 and an immediate release reference standard in a bioavailability study, as set forth in Table XXII and XXIII below:

TABLE XXII
Pharmacokinetic data
(Fasted State) Hydrocodone Bitartrate
Cmax (ng/ml) 43.16
IR reference product
(Dose adjusted)
Cmax (ng/ml) 17.87
CR product
Cmax (CR)/Cmax 41%
(IR)
Tmax (hr) 6.42
IR reference product
Tmax(hr) 4.04
CR product

TABLE XXXIII
Hydrocodone
Hydrocodone Hydrocodone Bitartrate IR
Bitartrate Bitartrate 2 × 7.5 mg
Pharmacokinetic CR 15 mg Tablets CR 15 mg Tablets Tablets
data (Fasted) (Fed) (Fasted)
Cmax (ng/ml) 17.87 19.23 21.58
C12 hour 11.06 12.84
C12 hour/Cmax 62% 67%
Tmax (hr) 4.04 4.81 6.42
AUC 267.43 277.58 229.33

Oshlack, Benjamin, Huang, Hua-Pin, Masselink, John, Tonelli, Alfred P.

Patent Priority Assignee Title
Patent Priority Assignee Title
2738303,
3424839,
3634584,
3845770,
3870790,
3916889,
3916899,
4063064, Nov 18 1974 Coherent Radiation Apparatus for tracking moving workpiece by a laser beam
4088864, Nov 18 1974 ALZA Corporation Process for forming outlet passageways in pills using a laser
4132753, Feb 12 1965 American Cyanamid Company Process for preparing oral sustained release granules
4377568, Aug 12 1981 Merck Sharp & Dohme (I.A.) Corp. Preparation of aqueous alcoholic dispersions of pH sensitive polymers and plasticizing agents and a method of enteric coating dosage forms using same
4385078, Sep 04 1978 Shin-Etsu Chemical Co., Ltd. Method for providing enteric coating on solid dosage forms and aqueous compositions therefor
4389393, Mar 26 1982 Forest Laboratories, Inc. Sustained release therapeutic compositions based on high molecular weight hydroxypropylmethylcellulose
4421736, May 20 1982 Merrel Dow Pharmaceuticals Inc. Sustained release diethylpropion compositions
4443428, Jun 21 1982 EUROCELTIQUE, S A Extended action controlled release compositions
4464378, Apr 28 1981 UNIVERSITY OF KENTUCKY RESARCH FOUNDATION,THE, LEXINGTON, KY A CORP OF KY Method of administering narcotic antagonists and analgesics and novel dosage forms containing same
4483847, Jun 28 1980 Warner-Lambert Company Process for the manufacture of a pharmaceutical composition with a retarded liberation of active material
4520172, Mar 11 1982 Rohm GmbH Method for coating medicaments
4539199, Jan 14 1981 EGYT Gyogyszervegyeszeti Gyar Sustained release pharmaceutical compositions
4548990, Aug 15 1983 Ciba-Geigy Corporation Crosslinked, porous polymers for controlled drug delivery
4557925, Jul 08 1982 Gacell Laboratories AB Membrane-coated sustained-release tablets and method
4600645, Jan 31 1985 WARNER-LAMBERT COMPANY, TABOR ROAD, MORRIS PLAINS, NEW JERSEY, A CORP OF DELAWARE Process for treating dosage forms
4609542, Dec 22 1978 Elan Corporation, P.L.C. New pharmaceutical forms for administration of medicaments by oral route, with programmed release
4708874, Mar 13 1985 Rijksuniversiteit Groningen Devices for the controlled release of active substances, as well as process for the preparation thereof
4728512, May 06 1985 AMERICAN HOME PRODUCTS CORPORATION, A CORP OF DE Formulations providing three distinct releases
4728513, Jul 31 1985 Zyma SA Granular delayed-release form of pharmaceutically active substances
4794001, May 06 1985 American Home Products Corporation Formulations providing three distinct releases
4797410, May 13 1985 MILES INC Suppression of withdrawal symptoms in opioid-induced tolerance or dependence
4806337, Jul 23 1984 WATSON LABORATORIES, INC Erodible matrix for sustained release bioactive composition
4814176, Jan 11 1985 Teijin Ltd. Sustained release preparation
4828836, Jun 05 1986 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS L P Controlled release pharmaceutical composition
4834984, Jun 10 1986 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS L P Controlled release dihydrocodeine composition
4834985, Jun 05 1986 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS L P Controlled release pharmaceutical composition
4844896, Nov 02 1987 DowElanco Microencapsulated insecticidal pathogens
4844909, Oct 31 1986 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS, L P Controlled release hydromorphone composition
4861596, Mar 21 1988 Pfizer Inc.; Pfizer Inc Rolled matrix device having enhanced ability to unroll and method for its production
4861598, Jul 18 1986 PURDUE PHARMA L P ; PURDUE FREDERICK COMPANY, THE; P F LABORATORIES, INC , THE; PURDUE PHARMA COMPANY, THE Controlled release bases for pharmaceuticals
4863456, Apr 30 1986 ALZA Corporation Dosage form with improved delivery capability
4873092, May 21 1987 Murata Kikai Kabushiki Kaisha Slow-releasing preparation
4888178, Jul 23 1986 ALFA WASSERMAN, S P A , VIA RAGAZZI DEL 99 NO 5, 40133 BOLOGNA, ITALY A CORP OF ITALY Galenic formulations with programmed release containing naproxen
4892742, Nov 18 1985 Hoffmann-La Roche Inc. Controlled release compositions with zero order release
4894234, Oct 05 1984 Cadbury Adams USA LLC Novel drug delivery system for antiarrhythmics
4904476, May 06 1985 American Home Products Corporation Formulations providing three distinct releases
4935246, Jul 01 1987 Hoechst Aktiengesellschaft Process for the coating of granules
4940588, Oct 30 1984 Elan Pharma International Limited Controlled release powder and process for its preparation
4948586, Nov 02 1987 DowElanco Microencapsulated insecticidal pathogens
4952402, Oct 30 1984 Elan Pharma International Limited Controlled release powder and process for its preparation
4956182, Mar 16 1989 Bristol-Myers Company Direct compression cholestyramine tablet and solvent-free coating therefor
4959219, Aug 15 1988 Fisons Corporation Coating barriers comprising ethyl cellulose
4970075, Jul 18 1986 PURDUE PHARMA L P ; PURDUE FREDERICK COMPANY, THE; P F LABORATORIES, INC , THE; PURDUE PHARMA COMPANY, THE Controlled release bases for pharmaceuticals
4971805, Dec 23 1987 Teysan Pharmaceuticals Co., Ltd. Slow-releasing granules and long acting mixed granules comprising the same
4983730, Sep 02 1988 DEUTSCHE BANK AG, NEW YORK BRANCH, AS COLLATERAL AGENT Water soluble cellulose acetate composition having improved processability and tensile properties
4990341, Oct 26 1987 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS, L P Controlled release hydromorphone composition
4996047, Nov 02 1988 RICHARDSON-VICKS, INC Sustained release drug-resin complexes
5002774, Jun 08 1989 FIRST NATIONAL BANK OF GRAPEVINE Sustained release pharmaceutical tablet
5007790, Apr 11 1989 ASSERTIO THERAPEUTICS, INC Sustained-release oral drug dosage form
5019397, Apr 21 1988 ALZA Corporation Aqueous emulsion for pharmaceutical dosage form
5023089, Jul 18 1988 Shionogi & Co., Ltd. Sustained-release preparations and the process thereof
5024842, Apr 28 1988 ALZA Corporation Annealed coats
5026560, Jan 29 1987 Takeda Pharmaceutical Company, Limited; TAKEDA PHARAMCEUTICAL COMPANY, LIMITED Spherical granules having core and their production
5030400, Jul 03 1989 NIRO HOLDING A S Process and an apparatus for agglomeration of a powdery material
5068110, Sep 29 1987 Warner-Lambert Company Stabilization of enteric coated dosage form
5071646, Nov 11 1988 Euroceltique, S.A. Pharmaceutical ion exchange resin composition
5102668, Oct 05 1990 Kingaform Technology, Inc. Sustained release pharmaceutical preparation using diffusion barriers whose permeabilities change in response to changing pH
5122384, May 05 1989 Drugtech Corporation Oral once-per-day organic nitrate formulation which does not induce tolerance
5126145, Apr 13 1989 KOS LIFE SCIENCES, INC Controlled release tablet containing water soluble medicament
5132142, Mar 19 1991 Glatt GmbH Apparatus and method for producing pellets by layering power onto particles
5133974, May 05 1989 Drugtech Corporation Extended release pharmaceutical formulations
5158777, Feb 16 1990 E. R. Squibb & Sons, Inc. Captopril formulation providing increased duration of activity
5162117, Nov 22 1991 Schering Corporation Controlled release flutamide composition
5167964, Feb 14 1992 Warner-Lambert Company Semi-enteric drug delivery systems and methods for preparing same
5169645, Oct 31 1989 DUQUESNE UNIVERSITY OF THE HOLY GHOST, A CORP OF PA Directly compressible granules having improved flow properties
5178868, Oct 26 1988 Gacell Laboratories AB Dosage form
5178878, Oct 02 1989 CIMA LABS, INC , A CORP DE Effervescent dosage form with microparticles
5196203, Jan 06 1989 F. H. Faulding & Co. Limited Theophylline dosage form
5202128, Jan 06 1989 ALPHARMA PHARMACEUTICALS LLC Sustained release pharmaceutical composition
5206030, Feb 26 1990 FMC Corporation Film-forming composition and use for coating pharmaceuticals, foods and the like
5219575, Jun 26 1987 Duphar International Research B.V. Compositions with controlled zero-order delivery rate and method of preparing these compositions
5226902, Jul 30 1991 ThermoLase Corporation Pulsatile drug delivery device using stimuli sensitive hydrogel
5229131, Feb 05 1990 TSRL, INC Pulsatile drug delivery system
5248516, Dec 19 1989 FMC Corporation Film-forming composition: method of producing same and use for coating pharmaceuticals and foods and the like
5258436, Dec 19 1989 FMC CORPORATION A CORP OF DE Film-forming composition; method of producing same and use for coating pharmaceuticals and foods and the like
5260068, May 04 1992 BANK OF AMERICA, N A , AS AGENT Multiparticulate pulsatile drug delivery system
5260069, Nov 27 1992 BANK OF AMERICA, N A , AS AGENT Pulsatile particles drug delivery system
5262173, Mar 02 1992 American Cyanamid Company Pulsatile once-a-day delivery systems for minocycline
5266331, Nov 27 1991 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS, L P Controlled release oxycodone compositions
5273760, Dec 24 1991 Purdue Pharma LP Stabilized controlled release substrate having a coating derived from an aqueous dispersion of hydrophobic polymer
5283065, Sep 21 1989 American Cyanamid Company Controlled release pharmaceutical compositions from spherical granules in tabletted oral dosage unit form
5286493, Jan 27 1992 Purdue Pharma LP Stabilized controlled release formulations having acrylic polymer coating
5292461, Aug 24 1990 SPRING AG, PHARMAZEUTISCHE PRAEPARATE A SWISS CORP Process for the production of pellets
5320853, May 20 1991 AVENTISUB INC ; AVENTIS HOLDINGS INC ; Aventisub II Inc Controlled release formulation for pharmaceutical compounds
5321012, Jan 28 1993 Virginia Commonwealth University Medical College Inhibiting the development of tolerance to and/or dependence on a narcotic addictive substance
5330759, Aug 26 1992 SANOFI-SYTHELABO Enteric coated soft capsules and method of preparation thereof
5330766, Jan 06 1989 ALPHARMA PHARMACEUTICALS LLC Sustained release pharmaceutical composition
5352683, Mar 05 1993 Virginia Commonwealth University Medical College of Virginia Method for the treatment of chronic pain
5354556, Oct 30 1984 Elan Pharma International Limited Controlled release powder and process for its preparation
5356467, Aug 13 1992 EUROCELTIQUE, S A Controlled release coatings derived from aqueous dispersions of zein
5378474, Jan 06 1989 ALPHARMA PHARMACEUTICALS LLC Sustained release pharmaceutical composition
5380790, Sep 09 1993 Eastman Chemical Company Process for the preparation of acrylic polymers for pharmaceutical coatings
5384130, Apr 18 1990 Asahi Kasei Kabushiki Kaisha; Asahi Kasei Chemicals Corporation Spherical seed cores, spherical granules and process for production thereof
5387421, Jan 31 1991 TSRL, INC Multi stage drug delivery system
5395628, Dec 28 1989 ROEHM GMBH & CO KG Controlled release succinic acid microcapsules coated with aqueous acrylics
5401512, Feb 22 1991 Delayed release oral dosage forms for treatment of intestinal disorders
5403593, Mar 04 1991 Novartis AG Melt granulated compositions for preparing sustained release dosage forms
5411745, May 25 1994 Purdue Pharma LP Powder-layered morphine sulfate formulations
5436011, Apr 16 1993 Bristol-Myers Squibb Company Solid pharmaceutical dosage form and a method for reducing abrasion
5439689, May 20 1991 VALEANT INTERNATIONAL BARBADOS SRL Diltiazem formulation
5445828, Jul 04 1990 ZAMBON S P A Programmed release oral solid pharmaceutical dosage form
5445829, May 05 1989 Drugtech Corporation Extended release pharmaceutical formulations
5456923, Apr 16 1991 Nippon Shinyaku Company, Limited Method of manufacturing solid dispersion
5458879, Mar 03 1994 Procter & Gamble Company, The Oral vehicle compositions
5460817, Jan 19 1988 Ciba Specialty Chemicals Water Treatments Limited Particulate composition comprising a core of matrix polymer with active ingredient distributed therein
5460826, Jun 27 1994 ALZA Corporation Morphine therapy
5460828, Jan 28 1993 RECORDATI S A , CHEMICAL AND PHARMACEUTICAL COMPANY Process for the preparation of microgranules suitable for suspension in fluids
5472708, Nov 27 1992 BANK OF AMERICA, N A , AS AGENT Pulsatile particles drug delivery system
5472712, Dec 24 1991 Purdue Pharma LP Controlled-release formulations coated with aqueous dispersions of ethylcellulose
5478577, Nov 23 1993 PURDUE PHARMA L P Method of treating pain by administering 24 hour oral opioid formulations exhibiting rapid rate of initial rise of plasma drug level
5484608, Mar 28 1994 Endo Pharmaceuticals Inc Sustained-release drug delivery system
5490990, Jun 25 1992 BASF Aktiengesellschaft Production of solid pharmaceutical depot forms
5500227, Nov 23 1993 EUROCELTIQUE, S A Immediate release tablet cores of insoluble drugs having sustained-release coating
5502058, Jul 21 1993 Virginia Commonwealth University Method for the treatment of pain
5503846, Mar 17 1993 CIMA LABS , INC Base coated acid particles and effervescent formulation incorporating same
5508040, May 04 1992 BANK OF AMERICA, N A , AS AGENT Multiparticulate pulsatile drug delivery system
5508042, Jun 18 1993 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS, L P Controlled release oxycodone compositions
5518730, Jun 03 1992 CHANTILLY BIOPHARMA LLC Biodegradable controlled release flash flow melt-spun delivery system
5520931, Jul 29 1992 Gacell Laboratories AB Controlled release morphine preparation
5534263, Feb 24 1995 ALZA Corporation Active agent dosage form comprising a matrix and at least two insoluble bands
5549912, Nov 27 1991 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS, L P Controlled release oxycodone compositions
5580578, Jan 27 1992 Purdue Pharma LP Controlled release formulations coated with aqueous dispersions of acrylic polymers
5593694, Oct 04 1991 Mitsubishi Pharma Corporation Sustained release tablet
5593695, Jun 27 1994 ALZA Corporation Morphine therapy
5601842, Sep 03 1993 Gruenenthal GmbH Sustained release drug formulation containing a tramadol salt
5614218, Mar 30 1993 Pharmacia & Upjohn Aktiebolag Controlled release preparation
5629011, Feb 05 1992 Archimedes Development Limited Composition for nasal administration
5629017, Jul 04 1990 ZAMBON S P A Programmed release oral solid pharmaceutical dosage form
5637320, Jan 15 1990 Elan Corporation, PLC Controlled absorption naproxen formulation for once-daily administration
5639476, Jan 27 1992 Purdue Pharma LP Controlled release formulations coated with aqueous dispersions of acrylic polymers
5654006, Feb 12 1993 Mayo Foundation for Medical Education and Research Condensed-phase microparticle composition and method
5656295, Nov 27 1991 PURDUE PHARMA L P ; P F LABORATORIES, INC , THE; PURDUE PHARMACEUTICALS, L P Controlled release oxycodone compositions
5667805, Jun 27 1994 ALZA Corporation Morphine therapy
5670172, Aug 12 1991 Euro-Celtique, S.A. Pharmaceutical spheroid formulation
5672360, Nov 22 1994 PURDUE PHARMA L P Method of treating pain by administering 24 hour oral opioid formulations
5681584, Apr 23 1993 Ciba-Geigy Corporation Controlled release drug delivery device
5681585, Dec 24 1991 Purdue Pharma LP Stabilized controlled release substrate having a coating derived from an aqueous dispersion of hydrophobic polymer
5726316, Jan 06 1995 TARGACEPT, INC Pharmaceutical compositions for prevention and treatment of central nervous system disorders
5731006, Apr 19 1991 Takeda Pharmaceutical Company, Limited Gastrointestinal mucosa-adherent granules, pharmaceutical preparations and a coating composition
5744166, Feb 25 1989 Archimedes Development Limited Drug delivery compositions
5753261, May 27 1994 Mayo Foundation for Medical Education and Research Lipid-coated condensed-phase microparticle composition
5776856, Feb 04 1997 ISP CAPITAL, INC Soluble polymer based matrix for chemically active water insoluble components
5807579, Nov 14 1996 Mayne Pharma International Pty Ltd Pseudoephedrine combination pharmaceutical compositions
5811126, Oct 02 1995 EURO-CELTIQUE, S A Controlled release matrix for pharmaceuticals
5820879, May 27 1994 Mayo Foundation for Medical Education and Research Method of delivering a lipid-coated condensed-phase microparticle composition
5820883, Oct 24 1986 Southern Research Institute; The UAB Research Foundation Method for delivering bioactive agents into and through the mucosally-associated lymphoid tissues and controlling their release
5834023, Mar 24 1995 BANK OF AMERICA, N A , AS AGENT Diltiazem controlled release formulation
5834024, Jan 05 1995 PUREPAC PHARMACEUTICAL CO Controlled absorption diltiazem pharmaceutical formulation
5837284, Dec 04 1995 Celgene Corporation; CELGENE CORPORTION Delivery of multiple doses of medications
5840329, May 15 1997 BioAdvances LLC Pulsatile drug delivery system
5840332, Jan 18 1996 DEXCEL PHARMA TECHNOLOGIES LTD Gastrointestinal drug delivery system
5840754, May 22 1995 ALZA Corporation Dosage form comprising oxybutynin
5843477, Sep 30 1997 Bayer Corporation Lubricants for use in tabletting
5843480, Mar 14 1994 Euro-Celtique, S.A. Controlled release diamorphine formulation
5849240, Nov 23 1993 Euro-Celtique, S.A. Method of preparing sustained release pharmaceutical compositions
5851555, Aug 15 1997 BIOVAIL TECHNOLOGIES LTD Controlled release dosage forms containing water soluble drugs
5858412, Jan 09 1995 J RETTENMAIER & SOEHNE GMBH + CO KG Sustained release formulations utilizing pharmaceutical excipient having improved compressibility with modified microcrystalline
5866161, Sep 16 1994 ALZA Corporation Hydrocodone therapy
5874090, Jul 14 1995 Celltech Pharma Europe Limited Sustained-release formulation of methylphenidate
5879705, Jul 27 1993 Euro-Celtique S.A. Sustained release compositions of morphine and a method of preparing pharmaceutical compositions
5885616, Aug 18 1997 IMPAX LABORATORIES, INC Sustained release drug delivery system suitable for oral administration
5891471, Nov 23 1993 Euro-Celtique, S.A. Pharmaceutical multiparticulates
5904927, Mar 14 1997 Northeastern University Drug delivery using pH-sensitive semi-interpenetrating network hydrogels
5955104, Jul 25 1996 MEDA PHARMA GMBH & CO KG Multiple unit oral pharmaceutical formulations
5958452, Apr 10 1997 PURDUE PHARMA L P Extruded orally administrable opioid formulations
5958458, Jun 15 1994 Actavis Group HF Pharmaceutical multiple unit particulate formulation in the form of coated cores
5958459, Jan 27 1992 PURDUE PHARMA L P Opioid formulations having extended controlled released
5965161, Nov 04 1994 PURDUE PHARMA L P Extruded multi-particulates
5965163, Nov 23 1993 Euro-Celtique, S.A. Substained release compositions and a method of preparing pharmaceutical compositions
5968551, Dec 24 1991 PURDUE PHARMA L P Orally administrable opioid formulations having extended duration of effect
5968661, Jun 28 1996 NKK Corporation; Sony Corporation Steel sheet for heat-shrink band
6024981, Apr 16 1997 CIMA LABS INC Rapidly dissolving robust dosage form
6025502, Mar 19 1999 TRUSTEES OF THE UNIVERSITY OF PENNSYLVANIA, THE Enantopselective synthesis of methyl phenidate
6039980, Jan 29 1996 EDWARD MENDELL CO , INC Sustained release excipient
6096148, Aug 10 1995 BASF Aktiengesellschaft Use of polymers based on ethylene, (meth)acrylates, and (meth)acrylic acid for coating or sealing panes of laminated safety glass
6103219, Jan 09 1995 J RETTENMAIER & SOEHNE GMBH + CO KG Pharmaceutical excipient having improved compressibility
6103261, Jul 01 1993 Purdue Pharma LP Opioid formulations having extended controlled release
6114423, Jul 21 1995 Wacker-Chemie GmbH Redispersable cross-linkable dispersion powders
6129933, Dec 24 1991 Purdue Pharma LP Stabilized controlled release substrate having a coating derived from an aqueous dispersion of hydrophobic polymer
6143322, Jul 01 1993 PURDUE PHARMA, L P Method of treating humans with opioid formulations having extended controlled release
6143353, Jan 27 1992 Purdue Pharma LP Controlled release formulations coated with aqueous dispersions of acrylic polymers
6155423, Apr 01 1997 CIMA LABS INC Blister package and packaged tablet
6156342, May 26 1998 BANK OF AMERICA, N A , AS AGENT Controlled release oral dosage form
6159501, Mar 08 1996 TAKEDA PHARMA A S Modified release multiple-units dosage composition for release of opioid compounds
6162467, Nov 23 1993 Euro-Celtique, S.A. Sustained release compositions and a method of preparing pharmaceutical compositions
6194005, Oct 01 1996 Gattefosse Holding Method for preparing a pharmaceutical composition with modified release of the active principle, comprising a matrix
6200604, Mar 27 1998 Cephalon, Inc Sublingual buccal effervescent
6217904, Apr 06 1999 MCLEAN HOSPTIAL Pharmaceutical dosage form for pulsatile delivery of d-threo-methylphenidate and a second CNS stimulant
6228398, May 08 2000 ATHYRIUM OPPORTUNITIES III ACQUISITION LP Multiparticulate modified release composition
6238704, Sep 13 1996 Shionogi & Co., Ltd. Sustained-release preparation utilizing thermal change and process for the production thereof
6245351, Mar 07 1996 Takeda Chemical Industries, Ltd. Controlled-release composition
6245357, Mar 06 1998 ALZA Corporation Extended release dosage form
6251430, Feb 04 1998 Water insoluble polymer based sustained release formulation
6261599, Nov 04 1994 PURDUE PHARMA L P Melt-extruded orally administrable opioid formulations
6262072, Oct 12 1999 Yung Shin Pharmaceutical Industrial Co. Ltd.; YUNG-SHIN PHARMA IND CO , LTD Orally administered antimicrobial pharmaceutical formulations of ciprofloxacin
6264983, Sep 16 1999 Rhodia Inc Directly compressible, ultra fine acetaminophen compositions and process for producing same
6290990, Apr 18 1994 BASF Aktiengesellschaft Slow-release matrix pellets and the production thereof
6294195, Dec 24 1991 PURDUE PHARMA L.P. Orally administrable opioid formulations having extended duration of effect
6294591, Dec 20 1996 BASF Coatings AG Method for producing polymers cross-linkable by radiation, acrylic or methacrylic acid esters
6300403, Sep 26 1997 Wacker-Chemie GmbH Method for producing polymers stabilized with protective colloids
6309668, Feb 01 1994 Rhone-Poulenc Rorer Limited Abuse resistant tablets
6316031, Dec 24 1991 Purdue Pharma LP Stabilized controlled release substrate having a coating derived from an aqueous dispersion of hydrophobic polymer
6322819, Oct 21 1998 Shire LLC Oral pulsed dose drug delivery system
6335033, Nov 04 1994 PURDUE PHARMA L P Melt-extrusion multiparticulates
6340476, Apr 06 1999 PHARMAQUEST LTD Pharmaceutical dosage form for pulsatile delivery of methylphenidate
6344215, Oct 27 2000 EURAND AMERICA, INC Methylphenidate modified release formulations
6368625, Aug 12 1998 CIMA LABS INC , A CORPORATION OF DELAWARE Orally disintegrable tablet forming a viscous slurry
6372254, Apr 02 1998 IMPAX LABORATORIES, INC Press coated, pulsatile drug delivery system suitable for oral administration
6375987, Oct 01 1996 Gattefosse Holding Process for the manufacture of pharmaceutical composition with modified release of active principle comprising the matrix
6387404, Nov 23 1993 PURDUE PHARMA L P Immediate release tablet cores of insoluble drugs having sustained-release coating
6399096, Sep 22 1995 Euro-Celtique S.A. Pharmaceutical formulation
6419954, May 19 2000 Astellas Pharma INC Tablets and methods for modified release of hydrophilic and other active agents
6419960, Dec 17 1998 RHODES PHARMACEUTICALS L P Controlled release formulations having rapid onset and rapid decline of effective plasma drug concentrations
6491945, Sep 16 1994 ALZA Corporation Hydrocodone therapy
6500459, Jul 21 1999 Controlled onset and sustained release dosage forms and the preparation thereof
6534091, Jul 02 1999 Cognis Iberia S. L. Microcapsules
6552031, Sep 17 1997 PRUDUE PHARMA, LP Synergistic analgesic combination of oxycodone and rofecoxib
6572885, Dec 24 1991 PURDUE PHARMA L P Orally administrable opioid formulations having extended duration of effect
6589960, Nov 09 1999 PURDUE PHARMA L P ; RHODES PHARMACEUTICALS L P Hydromorphone and hydrocodone compositions and methods for their synthesis
6599529, Sep 11 1997 TAKEDA PHARMA A S Modified release multiple-units compositions of non-steroid anti-inflammatory drug substances (NSAIDs)
6607750, Sep 16 1999 Rhodia Inc.; Rhodia Inc Directly compressible acetaminophen compositions
6680071, Mar 03 1999 CATALENT USA WOODSTOCK, INC ; CATALENT USA PACKAGING, LLC; CATALENT PHARMA SOLUTIONS, INC ; CATALENT USA PAINTBALL, INC Opioid agonist in a fast dispersing dosage form
6685964, Jan 18 1999 Gruenenthal GmbH Opioid analgesics with controlled active substance release
6696066, Dec 22 1997 PURDUE PHARMA L P Opioid agonist/antagonist combinations
6699502, Mar 14 1997 UCB PHARMA, S A Pharmaceutical compositions for controlled release of active substances
6706281, Nov 04 1994 PURDUE PHARMA L P Melt-extrusion multiparticulates
6730321, Apr 02 1998 IMPAX LABORATORIES, INC Press coated, pulsatile drug delivery system suitable for oral administration
6730325, Nov 02 1998 ATHYRIUM OPPORTUNITIES III ACQUISITION LP Multiparticulate modified release composition
6733783, Oct 30 2000 PURDUE PHARMA L P Controlled release hydrocodone formulations
6733790, Jul 02 1999 Cognis Iberia S. L. Microcapsules and processes for making the same using various polymers and chitosans
6743442, Nov 04 1994 PURDUE PHARMA L P Melt-extruded orally administrable opioid formulations
6753014, Sep 10 1999 AstraZeneca AB Method to obtain microparticles
6759059, Sep 24 1998 Diabact AB Fentanyl composition for the treatment of acute pain
6780504, Jul 13 1999 Gruenenthal GmbH Active substance-containing multi-layer film of hydrophilic polymers crosslinked in situ
6793936, Nov 02 1998 ATHYRIUM OPPORTUNITIES III ACQUISITION LP Multiparticulate modified release composition
6863901, Nov 30 2001 HIRSH, JANE; HIRSH, MARK Pharmaceutical composition for compressed annular tablet with molded triturate tablet for both intraoral and oral administration
6902742, Nov 02 1998 ATHYRIUM OPPORTUNITIES III ACQUISITION LP Multiparticulate modified release composition
6905709, Dec 24 1991 Purdue Pharma, LP Stabilized controlled release substrate having a coating derived from an aqueous dispersion of hydrophobic polymer
7022313, Feb 03 1999 Powderject Research Limited Hydrogel particle formulation
7090867, Oct 10 1997 Intellipharmaceutics Corp Controlled release delivery device for pharmaceutical agents incorporating microbial polysaccharide gum
7387792, Nov 30 2001 HIRSH, JANE; HIRSH, MARK Pharmaceutical composition for compressed annular tablet with molded triturate tablet for both intraoral and oral administration
7399488, Jul 05 2002 COLLEGIUM PHARMACEUTICAL, INC Abuse-deterrent pharmaceutical compositions of opiods and other drugs
7514100, Oct 30 2000 PURDUE PHARMA L P Controlled release hydrocodone formulations
7658939, Feb 08 2000 PURDUE PHARMA L P Tamper-resistant oral opioid agonist formulations
7776314, Jun 17 2002 Grunenthal GmbH Abuse-proofed dosage system
7790215, Mar 26 2002 PURDUE PHARMA L P Sustained-release gel coated compositions
7846476, May 02 2001 PURDUE PHARMA L P Once-a-day oxycodone formulations
7943174, Oct 29 1999 PURDUE PHARMA L P Controlled release hydrocodone formulations
8142811, Oct 30 2000 PURDUE PHARMA L.P. Controlled release hydrocodone formulations
8231898, Oct 30 2000 PURDUE PHARMA L.P. Controlled release hydrocodone formulations
8361499, Oct 30 2000 PURDUE PHARMA L P Controlled release hydrocodone formulations
8551520, Oct 30 2000 PURDUE PHARMA L P Controlled release hydrocodone
8647667, Oct 30 2000 PURDUE PHARMA L P Controlled release hydrocodone formulations
8715721, Oct 30 2000 PURDUE PHARMA L.P. Controlled release hydrocodone
20020012675,
20020044966,
20020110595,
20020110598,
20030077297,
20030180362,
20030190358,
20040009219,
20040028735,
20040052844,
20040096499,
20040096500,
20040105887,
20040121001,
20040131552,
20040142035,
20040151791,
20040157784,
20040170680,
20040185098,
20040197405,
20040208930,
20040208936,
20040224017,
20040253310,
20040266807,
20050020613,
20050053656,
20050074493,
20050089568,
20050106249,
20050163856,
20050165038,
20050169989,
20050169990,
20050245483,
20050266072,
20060003004,
20060024361,
20060104909,
20060153915,
20060153916,
20060204573,
20060233879,
20060233880,
20060240105,
20060251721,
20060263429,
20060269604,
20070003617,
20070009598,
20070020335,
20070203165,
20070212414,
20070231268,
20070281021,
20080069891,
20080102121,
20080132532,
20080226734,
20080311205,
20090149479,
20090238868,
20090297617,
20090304793,
20090317355,
20100010030,
20100015223,
20100040689,
20100098771,
20100249045,
20100323016,
20110065628,
20110262532,
20120164220,
20120165358,
20130209560,
20130295177,
20130302418,
20140112981,
20140161879,
AU199944493,
AU9047732,
AU9341654,
CA2082573,
CA2131350,
EP97523,
EP108218,
EP147780,
EP202051,
EP235986,
EP253104,
EP267702,
EP271193,
EP274734,
EP311582,
EP327295,
EP338444,
EP361680,
EP361910,
EP377517,
EP377518,
EP388954,
EP415693,
EP430287,
EP452145,
EP499299,
EP502642,
EP532348,
EP533297,
EP534628,
EP535841,
EP546676,
EP548448,
EP553392,
EP580860,
EP609961,
EP636370,
EP647448,
EP665010,
EP965343,
EP1419766,
EP1442745,
EP1504757,
EP1782834,
GB2053681,
GB2170104,
GB2178313,
GB2179254,
HU202403,
JP40081086,
JP8157392,
RE35200, Feb 15 1984 Rohm GmbH Coating for pharmaceutical dosage forms
RU2069558,
WO25752,
WO59479,
WO59481,
WO158433,
WO2009036287,
WO9703672,
WO9703673,
WO9725028,
WO9732093,
WO9814168,
WO9828345,
WO9833378,
WO9903471,
WO9951209,
WO24383,
WO72847,
WO132148,
WO2087512,
WO2092059,
WO236099,
WO2004026256,
WO2004064807,
WO2004084865,
WO2004093819,
WO2004108117,
WO2005020929,
WO2005034930,
WO2005041968,
WO2005099674,
WO2006109183,
WO2007048233,
WO2007103293,
WO2007112574,
WO2008140460,
WO2009036812,
WO2009059701,
WO2010033195,
WO2012131463,
WO9201446,
WO9202209,
WO9206679,
WO9208459,
WO9304675,
WO9307859,
WO9307861,
WO9310765,
WO9318753,
WO9403160,
WO9403161,
WO9405262,
WO9422431,
WO9428882,
WO9514460,
WO9600066,
WO9601629,
WO9608253,
WO9614058,
WO9702020,
WO9733566,
WO9817261,
WO9820095,
WO9841194,
WO9902142,
WO9932093,
WO9932120,
WO9939698,
/
Executed onAssignorAssigneeConveyanceFrameReelDoc
Dec 03 2013PURDUE PHARMA L.P.(assignment on the face of the patent)
Date Maintenance Fee Events


Date Maintenance Schedule
Mar 10 20184 years fee payment window open
Sep 10 20186 months grace period start (w surcharge)
Mar 10 2019patent expiry (for year 4)
Mar 10 20212 years to revive unintentionally abandoned end. (for year 4)
Mar 10 20228 years fee payment window open
Sep 10 20226 months grace period start (w surcharge)
Mar 10 2023patent expiry (for year 8)
Mar 10 20252 years to revive unintentionally abandoned end. (for year 8)
Mar 10 202612 years fee payment window open
Sep 10 20266 months grace period start (w surcharge)
Mar 10 2027patent expiry (for year 12)
Mar 10 20292 years to revive unintentionally abandoned end. (for year 12)