Title of Invention

A PROCESS FOR PREPARING A CELECOXIB DRUG SUBSTANCE

Abstract 1. A process for preparing a celecoxib drug substance, the process comprising: (a) melting! celecoxib; (b) rapidly cooling; the resulting melted celecoxib to form a celecoxib drug substance wherein the celecoxib is present, in at least a detectable amount, in amorphous form; and optionally • (c) grinding the celecoxib drug substahce to form a celecoxib. drug substance powder.
Full Text ORIGINAL
IN/PCT/2001/01053/MUM


FORM 2
THE PATENTS ACT, 1970
[39 OF 1970]
COMPLETE SPECIFICATION [See Section 10; Rule 13]
"A PROCESS FOR PREPARING A CELECOXIB DRUG SUBSTANCE
PHARMACIA CORPORATION, of P O Box 5110, Chicago, Illinois 60680,
United States of America,

The following specification particularly describes the nature .. of the invention and the manner in which it is to be performed:-
GRANETED
24/4/2006

The present invention relates to a celecoxib drug substance and a process for preparing the same.
. The present invention relates to the selective cyclooxygenase-2 inhibitory drug celecoxib and in particular to solid-state forms of that drug, to pharmaceutical compositions comprising such solid-state forms, and to processes for preparing them. The invention further relates to methods of treatment of cyclooxygenase-2 mediated disorders comprising administering such solid-state forms or compositions thereof to a subject, and to use of such solid-state forms in the manufacture of medicaments.
BACKGROUND-OF THE INVENTION
Celecoxib, also known as 4-[5-(4-methylphenyl)-3-(trifluoromethyI)-lH-pyrazol-l-yl]benzenesulfdnamide (I), the active ingredient of Celebrex® marketed by Pharmacia Corp., has a therapeutically and prophylactically useful selective cyclooxygenase-2 inhibitory effect, and has utility in treatment and prevention of specific cyclooxygenase-2 mediated disorders and of such disorders in general. Celecoxib has the structure:

Processes for preparing celecoxib are set forth in U.S. Patent No. 5,466,823 to f alley el al. and in U.S. Patent No. 5,892,053 to Zhi & Newaz, both incorporated herein by reference. Co-assigned International Patent Publication No. WO 00/32189, incorporated herein by reference, discloses that celecoxib has a crystal morphology which tends to form long, cohesive needles. Co-assigned International Patent Publication No. WO 00/42021, incorporated herein by reference, discloses a solvated crystalline form of celecoxib and a method for desolvation of that crystalline form.
A need for new forms of celecoxib, in particular forms suitable for preparing

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rapid-onset compositions, exists. Rapid-onset drug-delivery systems can provide
significant benefits over conventional dosage forms. Generally, rapid-onset
preparations provide a short period to therapeutic or prophylactic response compared

to conventional immediate-release or sustained-release dosage forms. For example, in 5 treatment of acute pain, a rapid-onset dosage form of celecoxib would be useful to
provide fast pain relief.
However, celecoxib presents certain challenges for formulation as a rapid-onset dosage form, particularly as a rapid-onset oral dosage form. For example, celecoxib has very low solubility in aqueous media and therefore is.not readily 10 dissolved and dispersed for rapid absorption in the gastrointestinal tract when
administered orally, for example in tablet or capsule form. In addition, celecoxib has
a relatively high dose requirement further increasing difficulties of providing a
sufficient therapeutically effective dose for rapid absorption.
Celecoxib crystals also present formulation difficulties as a result of unique
15 physical and chemical characteristics such as electrostatic and cohesive properties,

low bulk density, low compressibility and poor flow properties. Due at least in part to these properties, celecoxib crystals tend to segregate and agglomerate together during mixing, resulting in a non-uniformly blended composition containing undesirably large, insoluble aggregates of celecoxib. For these and other reasons, therefore, it is
20 difficult to prepare an orally deliverable, rapid-onset composition containing
celecoxib that has the desired blend uniformity.
The bioavailability of an orally administered drug, as measured by its entry
into systemic circulation in the bloodstream, depends on at least two fundamental
processes: drug dissolution in gastrointestinal fluids (in vivo drug release) and
25 subsequent absorption of the dissolved drug. Several factors influence dissolution of
a drug from its carrier, including surface area of the drug presented to the dissolution
solvent medium, solubility of the drug substance in the specific solvent medium, and
driving forces of the saturation concentration of dissolved materials in the solvent
medium. Notwithstanding these factors, a strong correlation has been established
30 between the in vitro dissolution time determined by standard assay procedures for an
oral dosage form and the rate of in vivo drug release. This correlation is so firmly
established in the art that dissolution time has become generally descriptive of drug
release potential for the active component of the particular unit dosage composition.

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When the process of in vivo drug release is slower than the process of absorption, absorption is said to be dissolution rate-limited. Since dissolution precedes absorption in the overall process, any change in the drug release or dissolution process will subsequently influence drug absorption. See for example 5 Lieberman et al. (1989), Pharmaceutical Dosage Forms: Tablets. Vol. 1, pp. 34-36.
Marcel Dekker, New York. It is clear, therefore, that dissolution time determined for
a composition is one of the important fundamental characteristics for consideration
when evaluating compositions intended for fast-onset delivery, particularly where
drug absorption is dissolution rate-limited.
10 Crystalline solids, due to their highly organized, lattice-like structures,
typically require a significant amount of energy for dissolution. The energy required
for a drug molecule to escape from a crystal, for example, is greater than is required
for the same drug molecule to escape from a non-crystalline, amorphous form.
Importantly, however, crystalline drug forms which have been transformed into 15 amorphous forms tend to revert to a steady state of low energy, namely the crystalline
form, over time and thus may not have an adequate shelf life. An amorphous form of
celecoxib has not hitherto been known in the art.

As indicated hereinbelow, treatment with celecoxib is indicated in a very wide
array of cyclooxygenase-2 mediated conditions and disorders. Therefore, if an
20 amorphous form of celecoxib could be prepared, and in particular if a storage-stable composition comprising such an amorphous form of celecoxib could be developed exhibiting enhanced bioavailability, for example through rapid dissolution of the drug, a significant advance would be realized in treatment of cyclooxygenase-2 mediated conditions and disorders, particularly in treatment of acute disorders where early relief
25 from pain or other symptoms is desired.
SUMMARY OF THE INVENTION Celecoxib provides a more rapid onset of therapeutic effect if, upon oral administration of a composition comprising celecoxib, pharmacokinetic properties are exhibited leading to a greater maximum blood serum concentration (Cmax ) and/or a 30 shorter time following the administration to reach that maximum (Tmax It is
contemplated that a greater Cmax and/or a shorter Tmax can result from faster dissolution of celecoxib when provided in amorphous form than in crystalline form.
when provided in amorphous form than in crystalline form.

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Accordingly, the present invention provides amorphous celecoxib. There is also provided a celecoxib drug substance wherein the celecoxib is present, in at least a detectable amount, as amorphous celecoxib. The term "celecoxib drug substance" as used herein means celecoxib per se as qualified by the context in which the term is 5 used, and can refer to unformulated celecoxib or to celecoxib present as an ingredient of a pharmaceutical composition.
As a further embodiment of the invention, there is provided a celccoxib-crystallization inhibitor composite comprising particles of amorphous celecoxib or a
celecoxib drug substance of the invention in intimate association with one or more
. 10 crystallization inhibitors. The crystallization inhibitors are selected and present in an
amount sufficient to substantially reduce conversion of amorphous celecoxib lo
crystalline celecoxib. Preferred crystallization inhibitors are polymers that form with
the celecoxib a celecoxib-polymer composite.
There is also provided a composition comprising a celecoxib-crystaliization
15 inhibitor composite, for example a celecoxib-polymer composite, as defined herein. The composition comprises dose units that can be in the form of discrete solid articles such as tablets, caplets, pills, hard or soft capsules, lozenges, sachets or pastilles; alternatively the composition can be in the form of a substantially homogeneous flowable mass, such as a particulate or granular solid or a liquid suspension, for
20 example an imbibable dispersion, from which single dose units are measurably removable.
Also provided are processes for preparing amorphous celecoxib. lor preparing
a celecoxib drug substance of the invention and for preparing a celecoxib-crystaliization inhibitor composite, for example a celecoxib-polymer composite, of the 25 invention.
A preferred process for preparing a celecoxib drug substance of the invention
comprises (a) a step of melting celecoxib, for example crystalline celecoxib; and (b) a
step of rapidly cooling the resulting melted celecoxib to form a celecoxib drug
substance wherein the celecoxib is present, in at least a detectable amount, in
30 amorphous form. Optionally, this process can further comprise (c) a step of grinding
the celecoxib drug substance to form a celecoxib powder.
A celecoxib-crystaliization inhibitor composite of the invention can be
prepared by a process comprising (a) a step of dissolving celecoxib and one or more

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.
crystallization inhibitors in a solvent liquid to form a solution; and (b) a step of drying the solution to form a celecoxib-crystallization inhibitor composite wherein the
celecoxib and the crystallization inhibitor are in intimate association and wherein a
substantial portion of the celecoxib is present in amorphous form. Optionally, this
5 process can further comprise (c) a step of grinding the celecoxib-crystallization
inhibitor composite to provide a celecoxib-crystallization inhibitor composite powder.
A celecoxib drug substance or powder thereof, or a celecoxib-crystallization
inhibitor composite or powder thereof, prepared according to such processes can be
further formulated to provide a pharmaceutical dosage form.
10 Also provided is a method of treating a medical condition or disorder in a
subject where treatment with a cyclooxygenase-2 inhibitor is indicated, comprising administering, for example orally, a composition of the invention in a therapeutically effective amount. Such a method is particularly useful where the medical condition or disorder is accompanied by acute pain.
15 Other features of this invention will be in part apparent and in pari pointed out
hereinafter.
IBRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 shows a powder X-ray diffraction profile of a celecoxib drug substance
C1 prepared in Example 1, by comparison with crystalline celecoxib C2.
20 Fig. 2 shows powder X-ray diffraction profiles of a celecoxib-polymer
composite C3 of the invention immediately after preparation (Tl) and following storage for 2 weeks at 40°C and 75% relative humidity (T2).
Fig.j'3 shows powder X-ray diffraction profiles of a celecoxib-polymer composite C4 of the invention immediately after preparation (Tl) and following 25 storage for 2 weeks at 40°C and 75% relative humidity (T2).
Fig.] 4 shows a differential scanning calorimetry (DSC) thermogram of a celecoxib drug substance C1 comprising no polymer.
Fig.' 5 shows a DSC thermogram of a celecoxib-polymer composite C3 of the
invention wherein the polymer is hydroxypropylmethylcellulose.
30 Fig. 6 shows a DSC thermogram of a celecoxib-polymer composite C4 of the
invention wherein the polymer is polyvinylpyrrolidone.

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DETAILED DESCRIPTION OF THE INVENTION Amorphous celecoxib
The invention provides a novel amorphous form of celecoxib. The term "amorphous"] as used herein, refers to solid-state particles lacking a regular crystalline 5 structure. Without being bound by theory, it is believed that amorphous celecoxib particles require less energy for dissolution than crystalline celecoxib particles of similar dimensions, and that this reduced dissolution energy requirement contributes, at least in part, to increased dissolution rate and/or decreased therapeutic onset time exhibited by amorphous celecoxib and compositions thereof.
10 Celecoxib drug substance of the invention I In addition to amorphous celecoxib per se, the invention provides a celecoxib
drug substance that comprises amorphous celecoxib. At least a detectable amount of
amorphous celecoxib is present. Preferably, about 10% to about 100%, more
preferably about 25% to about 100%, still more preferably about 60% to about 100%,
15 and even more preferably about 80% to about 100%, by weight of the celecoxib in a
celecoxib drug substance of the invention is amorphous. In a particular embodiment,
substantially all of the celecoxib is amorphous, i.e., the celecoxib drug substance is
substantially phase pure amorphous celecoxib.
A preferred celecoxib drug substance is an entirely solid-state substance
20 wherein the fraction, if any, of the celecoxib that is not amorphous, is crystalline. For example, a microparticulate or nanoparticulate celecoxib drug substance of this embodiment can, in addition to an amorphous celecoxib fraction, comprise a fraction of microcrystalline or nanocrystalline celecoxib, though this crystalline fraction is preferably small, for example, less than about 50%, more preferably less than about
25 25%, and still more preferably less than about 10%, by weight of the total celecoxib
present.
In one embodiment, the amount of amorphous celecoxib in a celecoxib drug substance is sufficient to provide increased dissolution rate as measured in a standard in vitro dissolution assay and/or improved bioavailability (e.g., shorter time to reach a
30 threshold therapeutic concentration in blood plasma, greater Cmax and/or shorter Tmax) as measured in a standard in vivo pharmacokinetic study, compared with an otherwise similar celecoxib drug substance wherein all, or a substantial portion of, the celecoxib

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is crystalline.
Amorphous celecoxib or a celecoxib drug substance of the invention can be
prepared by any suitable process, not limited to processes described herein.
One illustrative process comprises (a) a step of melting solid-state celecoxib,
5 e.g., crystalline celecoxib; and (b) a step of rapidly cooling the resulting melted
celecoxib to form a celecoxib drug substance wherein the celecoxib is present, in at
least a detectable amount, in amorphous form. This process optionally further
comprises (c) a step of grinding the celecoxib drug substance resulting from step (b)
to form a drug powder.
10 Melting step (a) can be performed by any technique known in the art, for
example, by heating the celecoxib in an oven at about 150°C to about 180°C. Cooling
step (b) can be performed by any suitable method, for example by floating a container
holding the melted celecoxib in liquid nitrogen. The optional grinding step (c) can be
performed by any suitable method, for example by grinding in a mortar and pestle or
15 by grinding in a mill, for example a media mill.
A celecoxib drug substance or drug powder prepared according to the above
process or any other process can be administered orally, rectally or parenterally
without further formulation, or in simple suspension in water or another
pharmaceutical y acceptable liquid. Alternatively, the celecoxib drug substance or
20 drug powder can be directly filled into capsules for oral administration. Preferably,
however, the celecoxib drug substance or drug powder is subjected to further
processing, typically with one or more excipients, to prepare a pharmaceutical
composition, for example an oral dosage form, as described hereinbelow.
Celecoxib-crvstallization inhibitor composites
25 In a presently preferred embodiment of the invention there is provided a
celecoxib-crystallization inhibitor composite comprising particles of amorphous celecoxib or a celecoxib drug substance having at least a detectable amount of amorphous celecoxib, in intimate association with one or more crystallization inhibitors. An intimate association" in the present context includes, for example,
30 celecoxib admixed with the crystallization inhibitor, celecoxib embedded or
incorporated in the crystallization inhibitor, celecoxib forming a coating on particles
of the crystallization inhibitor or vice versa, and a substantially homogeneous


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dispersion 6 of celecoxib throughout the crystallization inhibitor. The term "substantially homogeneous" herein with reference to a composite or pharmaceutical composition that comprises multiple components means that the components are sufficiently mixed such that individual components are not present as discrete layers 5 and do not form concentration gradients within the composition.
A cel ecoxib-crystallization inhibitor composite of this embodiment preferably comprises about 1% to about 95%, preferably about 10% to about 90%, more preferably about 25% to about 85%, and still more preferably about 30% to about 80%, by weight, of celecoxib. As indicated above, celecoxib in such a composite 10 exists, at least in a detectable amount, in amorphous form. Preferably, about 10% to about 100%, more preferably about 50% to about 100%, and still more preferably about 75% to about 100%, by weight of the total celecoxib in the composite is
amorphous celecoxib.
In composites of this embodiment, a fraction of the celecoxib can be present as
15 microcrystalline or nanocrystalline celecoxib, though this fraction is preferably small, for example less than about 50%, more preferably less than about 25%, and still more preferably less than about 10%, by weight of the total celecoxib in the composite. Crystallization inhibitors include any material which substantially reduces conversion of amorphous celecoxib to crystalline celecoxib, for example, polymers,
20 carbohydrates] lipids, etc. The term "substantially" with respect to reducing such
conversion includes completely inhibiting, preventing, slowing, delaying, decreasing or restricting crystallization of celecoxib to a measurable degree. It will be understood that both selection of crystallization inhibitor(s) and the amount of crystallization inhibitor(s) used in a composite of the invention influences stability of
25 amorphous celecoxib therein.
Crystallization inhibitors are preferably polymers, more preferably polymers
of low solubility in water. Still more preferably, such polymers are substantially non-
crosslinked.
Non-limiting examples of suitable polymers that can be used as crystallization
30 inhibitors include, either alone or in combination, polyvinylpyrrolidone (PVP or
povidone, e.g., Kollidon™ CLM of BASF), hydroxypropylmethylcellulose (HPMC,
e.g., Methocel™ E5 Premium), HPMC phthalate, ethylcellulose,
hydroxyethylcellulose, sodium carboxymethylcellulose (carmellose sodium), calcium


PCT/USOO/32435 WO 01/42221
carboxymethylcellulose, dextran, acacia, starches such as sodium starch elycolate
(SSG, e.g., Explotab™ R of Mendell), p-cyclodextrin (e.g., KJeptose™ 4PC of
Roquette), block copolymers of ethylene oxide and propylene oxide (e.g., Pluronic™
F-68 and F-108), polyvinyl alcohol and polyethylene glycol (PEG). Povidone and
5 HPMC are preferred polymers for use as crystallization inhibitors and form celecoxib-
polymer composites of the invention.
HPMCs vary in the chain length of their cellulosic backbone and consequently
in their viscosity as measured for example at a 2% by weight concentration in water.
HPMC used in celecoxib-polymer composites of the invention should have a
10 viscosity, 2% in water, of about 100 to about 100,000 cP, preferably about 1000 to
about 15,000 cP, for example about 4000 cP. Molecular weight of HPMC used in

celecoxib-polymer composites of the invention is preferably greater than about 10,000
but preferably not greater than about 1,500,000, more preferably not greater than
about 1,000,000, still more preferably not greater than about 500,000, and even more
15 preferably not greater than about 150,000.
HPMCs also vary in the relative degree of substitution of available hydroxyl groups on the cellulosic backbone by methoxy and hydroxypropoxy groups. With increasing hydroxypropoxy substitution, the resulting HPMC becomes more hydrophilic in nature. It is preferred in celecoxib-HPMC composites of the present
20 invention to use HPMC having about 15% to about 35%, preferably about 19% to about 32%, and more preferably about 22% to about 30%, methoxy substitution, and having about 3% to about 15%, preferably about 4% to about 12%, and more preferably about 7% to about 12%, hydroxypropoxy substitution.
HPMCs which can be used in the present invention are illustratively available
15 under the brand names Methocel™ of Dow Chemical Co. and Metolose™ of Shin-Etsu Chemical Co. Examples of particularly suitable HPMCs having medium viscosity includeMethocel™ E4M and Methocel™ K4M, both of which have a viscosity, 2% in water, of about 4000 cP. Examples of HPMCs having higher viscosity include Methocel™ E10M, Methocel™ K15M and Methocel™ K100M,
50 which have viscosities, 2% in water, of 10,000 cP, 15,000 cP and 100,000 cP respectively.
Preferred povidones used in celecoxib-polymer composites of the invention have a molecular weight of about 2,500 to about 3,000,000, preferably about 8,000 to

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about 1,000,000, and more preferably about 10,000 to about 400,000, for example,
about 50,000. Preferably, povidone used in celecoxib-polymer composites have a
dynamic viscosity, 10% in water at 20°C, of about 1.3 to about 700, preferably about
1.5 to about 30.0, and more preferably about 3.5 to about 8.5 mPa s.
5 In celecoxib-crystallization inhibitor composites, for example celecoxib-
polymer composites, of the invention, the amount of crystallization inhibitor is preferably sufficient such when maintained in an open dish at ambient temperature for a period of 7 days, transformation of amorphous celecoxib to crystalline celecoxib is no greater than about 50%, preferably no greater than about 25%, and more preferably 10 no greater than about 10%, by weight of all celecoxib in the composite.
Typically, depending on the particular polymer(s) used, one or more polymers are present in a contemplated celecoxib-polymer composite in a total amount of about 10% to about 80,%, preferably about 15% to about 75%, and more preferably about 25% to about 65%, by weight. Preferably, the weight ratio of celecoxib to polymer is 15 about 1:1000 to about 10:1, more preferably about 1:10 to about 5:1, and still more preferably about 1:2 to about 2.5:1.
A celecoxib-crystallization inhibitor composite of the invention can be prepared by any suitable process, not limited to processes described herein.
One illustrative process comprises (a) a step of dissolving celecoxib and one or 20 more crystallization inhibitors in a solvent liquid to form a solution; and (b) a step of drying the solution to form a celecoxib-crystallization inhibitor composite wherein the celecoxib and the crystallization inhibitor are in intimate association and wherein at least a detectable fraction of the celecoxib is in amorphous form. Optionally, this process can further comprise a step (c) of grinding the celecoxib-crystallization 25 inhibitor composite to form a celecoxib-crystallization inhibitor composite powder. Suitable solvent liquids which can be used to prepare a celecoxib-crystallization inhibitor composite, for example a celecoxib-polymer composite, can comprise any pharmaceutically acceptable solvent in which celecoxib can be dissolved. Heat and stirring can be used to facilitate drug dissolution in the solvent 30 liquid. The solvent liquid can also comprise a non-solvent fraction, for example,
water. Non-limiting examples of suitable solvents that may be used in solvent liquids of the invention include, for example, water-alcohol mixtures, methanol, ethanol, isopropanol, higher alcohols, propylene glycol, ethyl caprylate, propylene glycol

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laurate, PEG, diethyl glycol monoethyl ether (DGME), tetraethylene glycol dimethyl
ether, triethylene glycol monoethyl ether, polysorbate 80, etc. Ethanol and
isopropanol are preferred solvents.
It has surprisingly been found that use of isopropanol as a solvent permits a
5 relatively high loading of celecoxib and polymer in the solution to be dried;
accordingly isopropanol is presently an especially preferred solvent.
The drying step (b) can be performed by any suitable means, for example, by
evaporation, lyophilization, conventional heating {e.g., in an oven), spray drying, etc.
Spray drying is a preferred method of drying. Any suitable spray drying method
10 known in the art can be employed. Generally, spray drying is a process by which a solution comprising dissolved drug and crystallization inhibitor is rapidly sprayed over a current of warm air, resulting in formation of dry powder.
The optional grinding step (c) can be performed by any suitable method, for example by grinding in a mortar and pestle or by grinding in a mill, for example a 15 media mill.
A ce ecoxib-crystalIization inhibitor composite, for example a celecoxib-polymer composite or a powder thereof, prepared according to the above process or any other process, can be administered orally, rectally or parenterally without further formulation, or in simple suspension in water or another pharmaceutically acceptable 20 liquid. Alternatively, the composite or powder thereof can be directly filled into capsules for oral administration. Preferably, however, the composite or powder thereof is subjected to further processing, typically with one or more additional excipients, to prepare a pharmaceutical composition, for example an oral dosage form, as described hereinbelow.
25 Pharmaceutical compositions
Amorphous celecoxib, a celecoxib drug substance or a celecoxib-
crystallization inhibitor composite as provided herein can be further formulated
together with one or more pharmaceutically acceptable excipients to produce a
pharmaceutical composition. The term "excipient" herein means any substance, not
30 itself a therapeutic agent, used as a carrier or vehicle for delivery of a therapeutic l| agent to a subject or added to a pharmaceutical composition to improve its handling or
storage properties or to permit or facilitate formation of a dose unit of the composition


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into a discrete article such as a capsule or tablet suitable for oral administration. Excipients include, by way of illustration and not limitation, diluents, disintegrants, binding agents, adhesives, wetting agents, lubricants, glidants, crystallization inhibitors, surface modifying agents, substances added to mask or counteract a 5 disagreeable taste or odor, flavors, dyes, fragrances, and substances added to improve appearance of the composition.
Excipients employed in compositions of the invention can be solids or liquids or both. Compositions of the invention containing excipients can be prepared by any known technique of pharmacy that comprises admixing an excipient with a drug or 10 therapeutic agent. A composition of the invention contains a desired amount of
celecoxib per dose unit and, if intended for oral administration, can be in the form, for example, of a tablet, a caplet, a pill, a hard or soft capsule, a lozenge, a cachet, a dispensable powder, granules, a suspension, an elixir, a liquid, or any other form reasonably adapted for such administration. If intended for parenteral administration, 15 it can be in the form, for example, of a suspension. If intended for rectal
administration! it can be in the form, for example, of a suppository. Presently preferred are oral dosage forms that are discrete dose units each containing a predetermined amount of the drug, such as tablets or capsules.
Non-limiting examples follow of excipients that can be used to prepare 20 pharmaceutical compositions of the invention.
Compositions of the invention optionally comprise one or more pharmaceutically acceptable diluents as excipients. Suitable diluents illustratively include, either individually or in combination, lactose, including anhydrous lactose and lactose monohydrate; starches, including directly compressible starch and 25 hydrolyzed starches (e.g., Celutab™ and Emdex™); mannitol; sorbitol; xylitol; dextrose (e.g., (terelose™ 2000) and dextrose monohydrate; dibasic calcium phosphate dihydrate; sucrose-based diluents; confectioner's sugar; monobasic calcium sulfate monohydrate; calcium sulfate dihydrate; granular calcium lactate trihydrate; dextrates; inositol; hydrolyzed cereal solids; amylose; celluloses including 30 microcrystalline cellulose, food grade sources of a- and amorphous cellulose {e.g., Rexcel™) and powdered cellulose; calcium carbonate; glycine; bentonite; polyvinylpyrrolidone; and the like. Such diluents, if present, constitute in total about 5% to about 99%, preferably about 10% to about 85%, and more preferably about

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20% to about 80%, of the total weight of the composition. The diluent or diluents selected preferably exhibit suitable flow properties and, where tablets are desired, compressibility.
Lactose and microcrystalline cellulose, either individually or in combination, 5 are preferred diluents. Both diluents are chemically compatible with celecoxib. The use of extragranular microcrystalline cellulose (that is, microcrystalline cellulose added to a wet granulated composition after a drying step) can be used to improve hardness (for tablets) and/or disintegration time. Lactose, especially lactose monohydrate, is particularly preferred. Lactose typically provides compositions
10 having suitab e release rates of celecoxib, stability, pre-compression flowability, and/or drying properties at a relatively low diluent cost. It provides a high density substrate that aids densification during granulation (where wet granulation is employed) and therefore improves blend flow properties.
Compositions of the invention optionally comprise one or more
15 pharmaceutically acceptable disintegrants as excipients, particularly for tablet
formulations. Suitable disintegrants include, either individually or in combination, . starches, including sodium starch glycolate (e.g., Explotab™ of Pen West) and pregelatinized corn starches (e.g.. National™ 1551, National™ 1550, and Colocorn™ 1500), clays (e.g., Veegum™ HV), celluloses such as purified cellulose,
20 microcrystalline cellulose, methylcellulose, carboxymethylcellulose and sodium carboxymethylcellulose, croscarmellose sodium (e.g., Ac-Di-Sol™ of FMC), alginates, crospovidone, and gums, such as agar, guar, locust bean, karaya, pectin and tragacanth gums.
Disintegrants may be added at any suitable step during the preparation of the
25 composition, particularly prior to granulation or during a lubrication step prior to compression. Such disintegrants, if present, constitute in total about 0.2% to about
30%, preferably about 0.2% to about 10%, and more preferably about 0.2% to about
5%, of the total weight of the composition.
Croscarmellose sodium is a preferred disintegrant for tablet or capsule
30 disintegration, and, if present, preferably constitutes about 0.2% to about 10%, more
preferably about 0.2% to about 7%, and still more preferably about 0.2% to about 5%,
of the total weight of the composition. Croscarmellose sodium confers superior
intragranular disintegration capabilities to granulated compositions of the present

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PCT/USOO/32435

invention.
Compositions of the invention optionally comprise one or more pharmaceutically acceptable binding agents or adhesives as excipients, particularly for tablet formulations. Such binding agents and adhesives preferably impart sufficient 5 cohesion to the powder being tableted to allow for normal processing operations such as sizing, lubrication, compression and packaging, but still allow the tablet to disintegrate and the composition to be absorbed upon ingestion. Suitable binding agents and adhesives include, either individually or in combination, acacia; tragacanth; sucrose; gelatin; glucose; starches such as, but not limited to, 10 pregelatinized starches {e.g., National™ 1511 and National™ 1500); celluloses such as, but not limited to, methylcellulose and carmellose sodium (e.g., Tylose™); alginic acid and salts of alginic acid; magnesium aluminum silicate; PEG; guar gum; polysaccharide acids; bentonites; povidone, for example povidone K-l 5, K-30 and K-29/32; polymethacrylates; HPMC; hydroxypropylcellulose (e.g., Klucel™); and 15 ethylcellulose (e.g., Ethocel™). Such binding agents and/or adhesives, if present, constitute in total about 0.5% to about 25%, preferably about 0.75% to about 15%, and more preferably about 1% to about 10%, of the total weight of the composition.
Compositions of the invention optionally comprise one or more pharmaceuticall,y acceptable wetting agents as excipients. Such wetting agents are 20 preferably selected to maintain the celecoxib in close association with water, a condition that is believed to improve bioavailability of the composition.
Non-limiting examples of surfactants that can be used as wetting agents in compositions of the invention include quaternary ammonium compounds, for example benzalkonium chloride, benzethonium chloride and cetylpyridinium chloride, dioctyl 25 sodium sulfosuccinate, polyoxyethylene alkylphenyl ethers, for example nonoxynol 9, nonoxynol 10, and octoxynol 9, poloxamers (polyoxyethylene and polyoxypropylene block copolymers), polyoxyethylene fatty acid glycerides and oils, for example polyoxyethylene (8) caprylic/capric mono- and diglycerides (e.g., Labrasol™ of Gattefosse), polyoxyethylene (35) castor oil and polyoxyethylene (40) hydrogenated 30 castor oil; polyoxyethylene alkyl ethers, for example polyoxyethylene (20) cetostearyl ether, polyoxyethylene fatty acid esters, for example polyoxyethylene (40) stearate, polyoxyethylene sorbitan esters, for example polysorbate 20 and polysorbate 80 (e.g., Tween™ 80 of 1CI), propylene glycol fatty acid esters, for example propylene glycol

WO 01/42221 PCT/US00/32435

laurate (e.g., Lauroglycol™ of Gattefosse), sodium lauryl sulfate, fatty acids and salts thereof, for example oleic acid, sodium oleate and triethanolamine oleate, glyceryl fatty acid esters, for example glyceryl monostearate, sorbitan esters, for example sorbitan monolaurate, sorbitan monooleate, sorbitan monopalmitate and sorbitan 5 monostearate', tyloxapol, and mixtures thereof. Such wetting agents, if present, constitute in total about 0.25% to about 15%, preferably about 0.4% to about 10%, and more preferably about 0.5% to about 5%, of the total weight of the composition.
Wetting agents that are anionic surfactants are preferred. Sodium lauryl sulfate is a particularly preferred wetting agent. Sodium lauryl sulfate, if present, 10 constitutes about 0.25% to about 7%, more preferably about 0.4% to about 4%, and still more preferably about 0.5% to about 2%, of the total weight of the composition. Compositions of the invention optionally comprise one or more . pharmaceutically acceptable lubricants (including anti-adherents and/or glidants) as excipients. Suitable lubricants include, either individually or in combination, glyceryl 15 behapate (e.g., Compritol™ 888); stearic acid and salts thereof, including magnesium, calcium and sodium stearates; hydrogenated vegetable oils (e.g., Sterotex™); colloidal silica.; talc; waxes; boric acid; sodium benzoate; sodium acetate; sodium fumarate; sodium chloride; DL-leucine; PEG (e.g., Carbowax™ 4000 and Carbowax™ 6000); sodium oleate; sodium lauryl sulfate; and magnesium lauryl 20 sulfate. Such lubricants, if present, constitute in total about 0.1% to about 10%,
preferably about 0.2% to about 8%, and more preferably about 0.25% to about 5%, of the total weight of the composition.
Magnesium stearate is a preferred lubricant used, for example, to reduce friction between the equipment and granulated mixture during compression of tablet 25 formulations.
Suitable anti-adherents include talc, cornstarch, DL-leucine, sodium lauryl sulfate and metallic stearates. Talc is a preferred anti-adherent or glidant used, for example, to reduce formulation sticking to equipment surfaces and also to reduce static in the blend. Talc, if present, constitutes about 0.1% to about 10%, more 30 preferably about 0.25% to about 5%, and still more preferably about 0.5% to about 2%, of the total weight of the composition.
Other excipients such as colorants, flavors and sweeteners are known in the pharmaceutical art and can be used in compositions of the present invention. Tablets

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can be coated, for example with an enteric coating, or uncoated. Compositions of the invention can further comprise, for example, buffering agents.
Optionally, one or more effervescent agents can be used as disintegrants and/or to enhance organoleptic properties of compositions of the invention. When 5 present in compositions of the invention to promote dosage form disintegration, one or more effervescent agents are preferably present in a total amount of about 30% to about 75%, and preferably about 45% to about 70%, for example about 60%, by weight of the composition.
According to a particularly preferred embodiment of the invention, an
10 effervescent agent, present in a solid dosage form in an amount less than that effective
to promote disintegration of the dosage form, provides improved dispersion of the
celecoxib in an aqueous medium. Without being bound by theory, it is believed that
the effervescent agent is effective to accelerate dispersion of celecoxib from the
dosage form in the gastrointestinal tract, thereby further enhancing absorption and
15 rapid onset of therapeutic effect. When present in a pharmaceutical composition of
the invention to promote intragaslrointestinal dispersion but not to enhance
disintegration, one or more effervescent agents are preferably present in an amount of
about 2.5% to about 15%, more preferably about 5% to about 10%, by weight of the
composition.
20 Suitable effervescent agents include, for example, either alone or in
combination, sodium bicarbonate, anhydrous citric acid, tartaric acid and dibasic sodium phosphate. Sodium bicarbonate and anhydrous citric acid are preferred effervescent agents.
Solid dosage forms of the invention can be prepared by any suitable process, 25 not limited to processes described herein.
An illustrative process comprises (a) a step of blending amorphous celecoxib,
a celecoxib drug substance, or a celecoxib-crystallization inhibitor composite of the
invention with one or more excipients to form a blend, and (b) a step of tableting or
encapsulating the blend to form tablets or capsules respectively.
30 . In a preferred process, solid dosage forms are prepared by a process
comprising (a) a step of blending amorphous celecoxib, a celecoxib drug substance, or a celecoxib-crystallization inhibitor composite of the invention with one or more excipients to form a blend, (b) a step of granulating the blend to form a granulate, and

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PCT/USO0/32435

(c) a step of tableting or encapsulating the blend to form tablets or capsules respectively. Step (b) can be accomplished by any dry or wet granulation technique known in the art, but is preferably a wet granulation step followed by a step of drying the resulting granulate prior to tableting or encapsulating. One or more diluents, one 5 or more disintegrants and one or more binding agents are preferably added, for
example in the blending step, a wetting agent can optionally be added, for example in
the granulating step, and one or more disintegrants are preferably added after
granulating but before tableting or encapsulating. A lubricant is preferably added
before tableting. Blending and granulating can be performed independently under low
10 or high shear. A process is preferably selected that forms a granulate that is uniform
in drug content, that readily disintegrates, that flows with sufficient ease so that
weight variation can be reliably controlled during capsule filling or tableting, and that
is dense enough in bulk so that a batch can be processed in the selected equipment and
individual doses fit into the specified capsules or tablet dies.
15 In an alternative embodiment, solid dosage forms are prepared by a process
that includes a spray drying step, wherein the amorphous celecoxib, celecoxib drug
substance or celecoxib-crystallization inhibitor composite is suspended with one or
more excipients in one or more sprayable liquids, preferably a non-aqueous sprayable
liquid, and then is rapidly spray dried over a current of warm air. This spray drying
20 process for preparing a pharmaceutical composition can be performed in addition to
any spray drying step used in preparation of a celecoxib-crystallization inhibitor
composite as described hereinabove, but formation of the celecoxib-cryslallization
inhibitor composite is preferably combined with a spray drying step for preparation of
the pharmaceutical composition.
25 A granulate or spray dried powder resulting from any of the above illustrative
processes can be compressed or molded to prepare tablets or encapsulated to prepare
capsules. Conventional tableting and encapsulation techniques known in the art can
be employed. Where coated tablets are desired, conventional coating techniques are
suitable.
30 Excipients for tablet compositions of the invention are preferably selected to
provide a disintegration time of less than about 30 minutes, preferably about 25
minutes or less more preferably about 20 minutes or less, and still more preferably
about 15 minutes or less, in a standard disintegration assay.
17

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Any tablet hardness convenient with respect to handling, manufacture, storage
and ingestion can be employed. For example, for 100 mg celecoxib tablets, hardness
is preferably at least about 4 kP, more preferably at least about 5 kP, and still more
preferably at bast about 6 kP. For 200 mg celecoxib tablets, hardness is preferably at
5 least about 7 kP, more preferably at least about 9 kP, and still more preferably at least
about 11 kP. The material to be tableted, however, should not be compressed to such
a degree that there is subsequent difficulty in achieving hydration when exposed to
gastric fluid.
Tablet friability preferably is less than about 1.0%, more preferably less than
10 0.8%, and still more preferably less than about 0.5% in a standard test.
Celecoxib dosage
Celecoxib dosage forms of the invention preferably comprise celecoxib in a daily dosage amount of about 10 mg to about 1000 mg, more preferably about 25 mg to about 400 mg, and most preferably about 50 mg to about 200 mg.
15 Compositions of the invention comprise one or more orally deliverable dose
units. Each dose unit comprises celecoxib in a therapeutically effective amount that is preferably about 10 mg to about 1000 mg. The term "dose unit" herein means a portion of a pharmaceutical composition that contains an amount of a therapeutic or prophylactic agent, in the present case celecoxib, suitable for a single oral
20 administration to provide a therapeutic effect. Typically one dose unit, or a small plurality (up to about 4) of dose units, in a single administration provides a dose comprising a sufficient amount of the agent to result in the desired effect. Administration of such doses can be repeated as required, typically at a dosage frequency of 1 to about 4 times per day.
25 It will be understood that a therapeutically effective amount of celecoxib for a
subject is dependent inter alia on the body weight of the subject. A "subject" herein
to which a therapeutic agent or composition thereof can be administered includes a
human patient of either sex and of any age, and also includes any nonhuman animal,
particularly a warm-blooded animal, more particularly a domestic or companion
30 animal, illustratively a cat, dog or horse. When the subject is a child or a small animal
{e.g., a dog), for example, an amount of celecoxib relatively low in the preferred range
of about 10 mg to about 1000 mg is likely to provide blood serum concentrations

WO 01/42221 PCT/USOO/32435
consistent with therapeutic effectiveness. Where the subject is an adult human or a
large animal {eg., a horse), achievement of such blood serum concentrations of
celecoxib are likely to require dose units containing a relatively greater amount of
celecoxib.
5 Typical 'dose units in a composition of the invention contain about 10, 20, 25,
37.5,50,75, 100, 125, 150, 175, 200, 250, 300, 350 or 400 mg of celecoxib. For an
adult human, a therapeutically effective amount of celecoxib per dose unit in a
composition of the present invention is typically about 50 mg to about 400 mg.
Especially preferred amounts of celecoxib per dose unit are about 100 mg to about
10 200 mg, for example about 100 mg or about 200 mg.
A dose unit containing a particular amount of celecoxib can be selected to
accommodate any desired frequency of administration used to achieve a desired daily
dosage. The daily dosage and frequency of administration, and therefore the selection
of appropriate dose unit, depends on a variety of factors, including the age, weight,
15 sex and medical condition of the subject, and the nature and severity of the condition
or disorder, and thus may vary widely.
When administered orally to a fasting adult human, a 100 mg dose unit
preferably exhibits a Tmax, of less than about 90 minutes, more preferably less than
about 60 minutes and most preferably less than about 45 minutes, and a Cmax, of at
20 least about 100 ng/ml, more preferably at least about 200 ng/ml. Typically a
composition of the invention provides a blood serum concentration of celecoxib of at
least about 50 ng/ml within 30 minutes of oral administration; preferred compositions
achieve such a concentration in as little as 15 minutes. This early rise in blood serum
concentration is believed to be associated with the rapid onset of therapeutic effect
25 achieved by compositions of the present invention.
The term foral administration" herein includes any form of delivery of a therapeutic agent or a composition thereof to a subject wherein the agent or composition is placed in the mouth of the subject, whether or not the agent or composition is immediately swallowed. Thus "oral administration" includes buccal
30 and sublingual as well as esophageal administration. Absorption of the agent can
occur in any part or parts of the gastrointestinal tract including the mouth, esophagus,
stomach, duodenum, ileum and colon. The term "orally deliverable" herein means
suitable for oral administration.


WO 01/42221 PC17US00/32435
Utility of compositions of the invention
Compositions of the invention are useful in treatment and prevention of a very wide range of disorders mediated by COX-2, including but not restricted to disorders characterized by inflammation, pain and/or fever. Such compositions are especially 5 useful as anti-inflammatory agents, such as in treatment of arthritis, with the
additional benefit of having significantly less harmful side effects than compositions of conventional nonsteroidal anti-inflammatory drugs (NSAIDs) that lack selectivity for COX-2 over COX-1. In particular, compositions of the invention have reduced potential for gastrointestinal toxicity and gastrointestinal irritation including upper 10 gastrointestinal ulceration and bleeding, reduced potential for renal side effects such as reduction in renal function leading to fluid retention and exacerbation of hypertension, reduced effect on bleeding times including inhibition of platelet function, and possibly a lessened ability to induce asthma attacks in aspirin-sensitive asthmatic subjects, by comparison with compositions of conventional NSAIDs. Thus 15 compositions of the invention are particularly useful as an alternative to conventional NSAIDs where such NSAIDs are contraindicated, for example in patients with peptic ulcers, gastritis regional enteritis, ulcerative colitis, diverticulitis or with a recurrent history of gastrointestinal lesions; gastrointestinal bleeding, coagulation disorders including anemia such as hypoprothrombinemia, hemophilia or other bleeding 20 problems; kidney disease; or in patients prior to surgery or patients taking anticoagulants.
Contemplated compositions are useful to treat a variety of arthritic disorders,
including but not limited to rheumatoid arthritis, spondyloarthropathies, gouty
arthritis, osteoarthritis, systemic lupus erythematosus and juvenile arthritis.
25 Such compositions are useful in treatment of asthma, bronchitis, menstrual
cramps, preterm labor, tendinitis, bursitis, allergic neuritis, cytomegalovirus infectivity, apop osis including HIV-induced apoptosis, lumbago, liver disease including hepatitis, skin-related conditions such as psoriasis, eczema, acne; bums, dermatitis and ultraviolet radiation damage including sunburn, and post-operative 30 inflammation including that following ophthalmic surgery such as cataract surgery or refractive surgery
Such compositions are useful to treat gastrointestinal conditions such as inflammatory bowel disease, Crohn's disease, gastritis, irritable bowel syndrome and

WO 01/42221 PCT/US00/32435

ulcerative colitis.
Such compositions are useful in treating inflammation in such diseases as migraine headaches, periarteritis nodosa, thyroiditis, aplastic anemia, Hodgkin's disease, sclerodoma, rheumatic fever, type I diabetes, neuromuscular junction disease 5 including myasthenia gravis, white matter disease including multiple sclerosis, sarcoidosis, nephrotic syndrome, Behcet's syndrome, polymyositis, gingivitis, nephritis, hypersensitivity, swelling occurring after injury including brain edema, myocardial ischemia, and the like.
Such compositions are useful in treatment of ophthalmic diseases, such as 10 retinitis, conjunctivitis, retinopathies, uveitis, ocular photophobia, and of acute injury
to the eye tissue.
Such compositions are useful in treatment of pulmonary inflammation, such as
that associated with viral infections and cystic fibrosis, and in bone resorption such as
that associated with osteoporosis.
15 Such compositions are useful for treatment of certain central nervous system
disorders, such as cortical dementias including Alzheimer's disease,
neurodegenerarion, and central nervous system damage resulting from stroke,
ischemia and trauma. The term "treatment" in the present context includes partial or
total inhibition of dementias, including Alzheimer's disease, vascular dementia,
20 multi-infarct dementia, pre-senile dementia, alcoholic dementia and senile dementia.
Such compositions are useful in treatment of allergic rhinitis, respiratory
distress syndrome, endotoxin shock syndrome and liver disease.
Such compositions are useful in treatment of pain, including but not limited to
postoperative pain, dental pain, muscular pain, and pain resulting from cancer. For
25 example, such compositions are useful for relief of pain, fever and inflammation in a
variety of conditions including rheumatic fever, influenza and other viral infections
including common cold, low back and neck pain, dysmenorrhea, headache, toothache,
sprains and strains, myositis, neuralgia, synovitis, arthritis, including rheumatoid
arthritis, degenerative joint diseases (osteoarthritis), gout and ankylosing spondylitis,
30 bursitis, bums, and trauma following surgical and dental procedures.
Such compositions are useful for treating and preventing inflammation-related
cardiovascular disorders, including vascular diseases, coronary artery disease,
aneurysm, vascular rejection, arteriosclerosis, atherosclerosis including cardiac
21

WO 01/42221 PCT/US00/32435
transplant atherosclerosis, myocardial infarction, embolism, stroke, thrombosis including venous thrombosis, angina including unstable angina, coronary plaque inflammation bacterial-induced inflammation including Chlamydia-induced inflammation viral induced inflammation, and inflammation associated with surgical 5 procedures such as vascular grafting including coronary artery bypass surgery,
revascularization procedures including angioplasty, stent placement, endarterectomy, or other invasive procedures involving arteries, veins and capillaries.
Such compositions are useful in treatment of angiogenesis-related disorders in
a subject, for example to inhibit tumor angiogenesis. Such compositions are useful in
10 treatment of neoplasia, including metastasis; ophthalmological conditions such as
corneal graft rejection, ocular neovascularization, retinal neovascularization including
neovascularization following injury or infection, diabetic retinopathy, macular
degeneration, retrolental fibroplasia and neovascular glaucoma; ulcerative diseases
such as gastric ulcer; pathological, but non-malignant, conditions such as
15 hemangiomas, including infantile hemaginomas, angiofibroma of the nasopharynx and avascular necrosis of bone; and disorders of the female reproductive system such as endometriosis.
Such compositions are useful in prevention and treatment of benign and malignant tumors and neoplasia including cancer, such as colorectal cancer, brain
20 cancer, bone cancer, epithelial cell-derived neoplasia (epithelial carcinoma) such as basal cell carcinoma, adenocarcinoma, gastrointestinal cancer such as lip cancer, mouth cancer, esophageal cancer, small bowel cancer, stomach cancer, colon cancer, liver cancer, bladder cancer, pancreas cancer, ovary cancer, cervical cancel', lung cancer, breast cancer, skin cancer such as squamous cell and basal cell cancers,
25 prostate cancer) renal cell carcinoma, and other known cancers that effect epithelial cells throughout the body. Neoplasias for which compositions of the invention are contemplated to be particularly useful are gastrointestinal cancer, Barrett's esophagus, liver cancer, bladder cancer, pancreatic cancer, ovarian cancer, prostate cancer, cervical cancer, lung cancer, breast cancer and skin cancer. Such compositions can
30 also be used to treat fibrosis that occurs with radiation therapy. Such compositions can be used to treat subjects having adenomatous polyps, including those with familial adenomatous polyposis (FAP). Additionally, such compositions can be used to prevent polyps from forming in patients at risk of FAP.

WO 01/42221 PCT/US00/32435
Such compositions inhibit prostanoid-induced smooth muscle contraction by inhibiting synthesis of contractile prostanoids and hence can be of use in treatment of dysmenorrhea', premature labor, asthma and eosinophil-related disorders. They also can be of use for decreasing bone loss particularly in postmenopausal women (i.e., 5 treatment of osteoporosis), and for treatment of glaucoma.
Preferred uses for compositions of the invention are for treatment of rheumatoid arthritis and osteoarthritis, for pain management generally (particularly post-oral surgery pain, post-general surgery pain, post-orthopedic surgery pain, and acute flares of osteoarthritis), for treatment of Alzheimer's disease, and for colon 10 cancer chemoprevention.
Besides being useful for human treatment, compositions of the invention are useful for veterinary treatment of companion animals, exotic animals, farm animals, and the like, particularly mammals. More particularly, compositions of the invention are useful for treatment of COX-2 mediated disorders in horses, dogs and cats.
15 Method of treatment
The present invention is further directed to a therapeutic method of treating a
condition or disorder where treatment with a COX-2 inhibitory drug is indicated, the
method comprising oral administration of a composition of the invention to a subject
in need thereof. The dosage regimen to prevent, give relief from, or ameliorate the
20 condition or disorder preferably corresponds to once-a-day or twice-a-day treatment,
but can be modified in accordance with a variety of factors. These include the type,
age, weight, sex' diet and medical condition of the subject and the nature and severity
of the disorder. Thus, the dosage regimen actually employed can vary widely and can
therefore deviate from the preferred dosage regimens set forth above.
25 Initial treatment can begin with a dose regimen as indicated above. Treatment
is generally continued as necessary over a period of several weeks to several months
or years until the condition or disorder has been controlled or eliminated. Subjects
undergoing treatment with a composition of the invention can be routinely monitored
by any of the methods well known in the art to determine effectiveness of therapy.
30 Continuous analysis of data from such monitoring permits modification of the
treatment regimen during therapy so that optimally effective doses are administered at
any point in time and so that the duration of treatment can be determined. In this

WO 01/42221 PCT/US00/32435
way, the treatment regimen and dosing schedule can be rationally modified over the
course of therapy so that the lowest amount of the composition exhibiting satisfactory
effectiveness is administered, and so that administration is continued only for so long
as is necessary to successfully treat the condition or disorder.
5 The present compositions can be used in combination therapies with opioids
and other analgesics, including narcotic analgesics, Mu receptor antagonists, Kappa receptor antagonists, non-narcotic (i.e. non-addictive) analgesics, monoamine uptake inhibitors, adenosine regulating agents, cannabinoid derivatives, Substance P antagonists, neurokinin-1 receptor antagonists and sodium channel blockers, among 10 others. Preferred combination therapies comprise use of a composition of the invention with one or more compounds selected from aceclofenac, acemetacin, e-acetamidocaproic acid, acetaminophen, acetaminosalol, acetanilide, acetylsalicylic acid (aspirin), S-adenosylmethionine, alclofenac, alfentanil, allylprodine, alminoprofen, aloxiprin, alphaprodine, aluminum bis(acetylsalicylate), amfenac, 15 aminochlorthenoxazin, 3-amino-4-hydroxybutyric acid, 2-amino-4-pico!ine, aminopropylony aminopyrine, amixetrine, ammonium salicylate, ampiroxicam, amtolmetin guacil, anileridine, antipyrine, antipyrine salicylate, antrafenine, apazone, bendazac, benowlate, benoxaprofen, benzpiperylon, benzydamine, benzylmorphine, bermoprofen, bezitramide, a-bisabolol, bromfenac, p-bromoacetanilide, 20 5-bromosalicylic acid acetate, bromosaligenin, bucetin, bucloxic acid, bucolome, bufexamac, bumadizon, buprenorphine, butacetin, butibufen, butophanol, calcium acetylsalicylate,carbamazepine, carbiphene, carprofen, carsalam, chlorobutanol, chlorthenoxazin, choline salicylate, cinchophen, cinmetacin, ciramadol, clidanac, clometacin, clonitazene, clonixin, clopirac, clove, codeine, codeine methyl bromide, 25 codeine phosphate, codeine sulfate, cropropamide, crotethamide, desomorphine, dexoxadrol, dextromoramide, dezocine, diampromide, diclofenac sodium, difenamizole, difenpiramide, diflunisal, dihydrocodeine, dihydrocodeinone enol acetate, dihydromorphine, dihydroxyaluminum acetylsalicylate, dimenoxadol, dimepheptanol, dimethylthiambulene, dioxaphetyl butyrate, dipipanone, diprocetyl, 30 dipyrone, ditazol droxicam, emorfazone, enfenamic acid, epirizole, eptazocine, etersalate, ethenzamide, ethoheptazine, ethoxazene, ethylmethylthiambutene, ethylmorphine, etodolac, etofenamate, etonitazene, eugenol, felbinac, fenbufen, fenclozic acid, fendosal, fenoprofen, fentanyl, fentiazac, fepradinol, feprazone, '

WO 01/42221 PCT/US00/32435
floctafenine, flufenamic acid, flunoxaprofen, fluoresone, flupirtine, fluproquazone, flurbiprofen, fosfosal, gentisic acid, glafenine, glucametacin, glycol salicylate, guaiazulene, hydrocodone, hydromorphone, hydroxypethidine, ibufenac, ibuprofen, ibuproxam, imidazole salicylate, indomethacin, indoprofen, isofezolac, isoladol, 5 isomethadonej isonixin, isoxepac, isoxicam, ketobemidone, ketoprofen, ketorolac, p-lactophenetide, lefetamine, levorphanol, lofentanil, lonazolac, lornoxicam, loxoprofen, lysine acetylsalicylate, magnesium acetylsalicylate, meclofenamic acid, mefenamic acid, meperidine, meptazinol, mesalamine, metazocine, methadone hydrochloride; rnethotrimeprazine, metiazinic acid, metofoline, metopon, 10 mofebutazonej mofezolac, morazone, morphine, morphine hydrochloride, morphine sulfate, morphpline salicylate, myrophine, nabumetone, nalbuphine, l-naphthyl salicylate, naproxen, narceine, nefopam, nicomorphine, nifenazone, niflumic acid, nimesulide, 5'-nitro-2'-propoxyacetanilide, norlevorphanol, normethadone, normorphine, norpipanone, olsalazine, opium, oxaceprol, oxametacine, oxaprozin, 15 oxycodone, oxymorphone, oxyphenbutazone, papaveretum, paranyline, parsalmide, pentazocine, perisoxal, phenacetin, phenadoxone, phenazocine, phenazopyridine hydrochloride, phenocoll, phenoperidine, phenopyrazone, phenyl acetylsalicylate, phenylbutazone!, phenyl salicylate, phenyramidol, piketoprofen, piminodine, pipebuzone, piperylone, piprofen, pirazolac, piritramide, piroxicam, pranoprofen, 20 proglumelacin, proheptazine, promedol, propacetamol, propiram, propoxyphene,
propyphenazonc, proquazone, protizinic acid, ramifenazone, remifentanil, rimazolium metilsulfate, salacetamide, salicin, salicylamide, salicylamide o-acetic acid, salicylsulfuric acid, salsalte, salverine, simetride, sodium salicylate, sufentanil, sulfasalazine, sulindac, superoxide dismutase, suprofen, suxibuzone, talniflumate, 25 tenidap, tenoxicam, terofenamate, tetrandrine, thiazolinobutazone, tiaprofenic acid, tiaramide, tilidine, tinoridine, tolfenamic acid, tolmetin, tramadol, tropesin, viminol, xenbucin, ximoprofen, zaltoprofen and zomepirac (see The Merck Index, 12th Edition, Therapeutic Category and Biological Activity Index, ed. S. Budavari (1996), pp. Ther-2 to Ther-3 and Ther-12 (Analgesic (Dental), Analgesic (Narcotic), 30 Analgesic (Non-narcotic), Anti-inflammatory (Nonsteroidal)).
Particularly preferred combination therapies comprise use of a composition of the invention with an opioid compound, more particularly where the opioid compound is codeine, meperidine, morphine or a derivative thereof.

WO 01/42221 PCT7US00/32435
A ce ecoxib composition of the invention can also be administered in combination with a second selective COX-2 inhibitory drug, for example valdecoxib,
rofecoxib, etc.
The compound to be administered in combination with celecoxib can be
5 formulated separately from the celecoxib or co-formulated with the celecoxib in a
composition of the invention. Where celecoxib is co-formulated with a second drug,
for example an opioid drug, the second drug can be formulated in immediate-release,
rapid-onset, sustained-release or dual-release form.
EXAMPLES
1 0 The following examples illustrate aspects of the present invention but are not
to be construed as limitations.
Example 1
A celecoxib drug substance C1 and celecoxib-polymer composites C3 and C4 were prepared by the following spray drying process. Celecoxib in crystalline form (a 15 celecoxib drug substance C2 of prior art) was added to a solvent, with stirring at a temperature of 70-75°C, to prepare solutions S1, S3 and S4 having the composition shown in Table 1,. Solutions S1 and S4 were prepared in 95% ethanol. Solution S3 was prepared in 70% isopropanol.

20 Each of solutions S1, S3 and S4 was spray dried individually at room
temperature using a Yamato GB-21 spray dryer to form powders C1, C3 and C4, respectively, under the following conditions: (a) liquid flow rate of 10 ml/min; (b) inlet air temperature of 115°C; (c) outlet air temperature of 75°C, and (d) drying
airflow of 3.75 TMF. Powders C3 and C4 are celecoxib-polymer composites of the
25 invention, each comprising 67% celecoxib and 33% polymer.
Example 2
A celecoxib drug substance C10 was prepared by the following melt/quench cool process.

PCT/US00/32435 WO 01/42221
Approximately 5 g of crystalline celecoxib (the prior art celecoxib dmg
substance C2) was weighed into a metal foil tray and placed in an oven at 180°C for 5
minutes to melt the celecoxib. This was then quench cooled by floating the foil tray
containing the melted celecoxib on liquid nitrogen, resulting in the formation of
5 celecoxib drug substance C10 of the present invention. This drug substance could be
gently ground by mortar and pestle to produce a celecoxib drug substance powder.
Example 3
Powder X-ray diffraction (PXRD) analysis was used to determine the relative crystalline and amorphous celecoxib content of celecoxib drug substance C1 and 10 celecoxib-polymer composites C3 and C4 as prepared in Example 1, by comparison with crystalline celecoxib drug substance C2. Data were collected using a Scintag Advanced Diffraction System operating under Scintag DMS/NT software. This system uses a peltier cooled solid stale detector and a copper X-ray source maintained at 45 kV and 40 mA to provide CuKa, emission at 1.5406 A. The beam aperture was 15 controlled using tube divergence and anti-scatter slits of 2 and 4 mm respectively, while the detector anti-scatter and receiving slits were set at 0.5 and 0.3 mm respectively. Data were collected from 2° to 35° two-theta (20) Using a scan step of 0.03°/point and a one second/point integration time. The samples were prepared using Scintag round top-loading stainless steel sample cups, and were fitted with 20 12 mm diameter aluminum inserts to accommodate small sample volumes.
The resu ts of the PXRD analyses are shown as bands in Figs. 1 -3. The appearance of larger, spiked peaks on a band indicates crystallinity whereas compressed peaks are indicative of amorphous material.
Fig. 1 shows that celecoxib alone (with no polymer) spray dried from an 25 ethanol solution (C1) produced a strong crystalline signal similar to that of a
crystalline celecoxib control (C2). If there is an amorphous component in celecoxib drug substance Cl it is a minor component.
Fig. 2 shows that when celecoxib was spray dried with HPMC (2:1 ratio by weight), the resulting celecoxib-polymer composite C3 was initially (at time T1) non-30 crystalline, i.e., the celecoxib in this composite was substantially phase pure
amorphous celecoxib. When analysis was conducted on a sample that had been stored for two weeks at 40°C and 75% relative humidity (at time T2), some recrystallization

WO 01/42221 PCT/US00/32435
had occurred as indicated by presence of crystalline peaks.
iFig. 3 shows that when celecoxib was spray dried with povidone (2:1 ratio by weight) the resulting celecoxib-polymer composite C4 was initially (at time T1) non¬crystalline, i.e\, the celecoxib in this composite was substantially phase pure 5 amorphous celecoxib. When analysis was conducted on a sample that had been stored for two weeks at 40°C and 75% relative humidity (at time T2), essentially no recrystallization had occurred, as indicated by absence of crystalline peaks.
Example 4
Differential scanning calorimetry (DSC) was used to determine relative 10 crystalline and amorphous celecoxib content of celecoxib drug substance CI and celecoxib-polymer composites C3 and C4 as prepared in Example 1. DSC was performed using a TA Instruments DSC 2920 differential scanning calorimeter with parameters set as follows: (a) temperature range of 50-200°C; (b) heating rate of 2°C/min, modulating ± 0.5°C every 30 sec; (c) sample size of 3 mg; (d) hermetically 15 sealed aluminum pans.
Figs. 4-6 show DSC thermograms for the spray dried powders of Example 1. Fig. 4 displays a thermogram for celecoxib drug product C1, exhibiting a large melting endotherm at 159.4°C (onset) with an area of 96.42 J/g. No other transitions are evident. The magnitude of the endotherm suggests that a substantial portion of C1 20 was crystalline. Any amorphous celecoxib present in the sample was not detectable
by this technique.
Fig. 5 displays a thermogram for celecoxib-polymer composite C3 (2:1
celecoxib:HPMC ratio). This material exhibits an apparent glass transition at 122.9°C
(onset), followed by a small melting endotherm at 150.1°C with an area of 4.379 J/g.
25 The endotherm indicates that most of the celecoxib in C3 is amorphous, but that a
small amount of crystalline celecoxib is present.
Fig. 6 displays a thermogram for celecoxib-polymer composite C4 (2:1
celecoxib:povidone ratio). This material exhibits an apparent glass transition at

111.4°C (onset)

No other transitions are evident, indicating that the material is

30 substantially phase pure amorphous celecoxib.
Example 5
DSC wasjalso used to determine relative crystalline and amorphous content of


WO 01/42221 PCT/US00/32435
celecoxib drug substance C10 prepared as in Example 2. DSC was performed using a TA Instruments MDSC differential scanning calorimeter at a scan rate of 5°C/min. A first significant thermal event was observed at about 54°C, representing a glass transition temperature indicative of amorphous celecoxib. An exothermic peak 5 observed at 00-105°C was consistent with a crystallization event and represents conversion of amorphous celecoxib to a crystalline state. As was shown by the presence of a endothermic peak, the resulting crystalline celecoxib melted at about 165°C.
Example 6
10 Tablets having the composition shown in Table 2 were prepared from
celecoxib-polymer composite C4 by the following procedure. Composite C4, sodium lauryl sulfate and effervescent agents (citric acid and sodium bicarbonate) were admixed and milled for 10 min in a McCrone mill to form a powder mixture. The powder mixture was ground together with lactose, microcrystalline cellulose and
15 sodium starch glycolate using a mortar and pestle to form a ground powder mixture. The ground powder mixture was then compressed using a Carver press to form tablets, which are illustrative of a pharmaceutical composition of the invention.
Table 2. Composition of tablets prepared from celecoxib-polymer composite C4

Example 7
20 Tablets prepared as described in Example 6 were compared with a crystalline

celecoxib capsule in an in vivo bioavailability assay in dogs. In a crossover design, each of six beagle dogs received a 200 mg dose of celecoxib in the form of the tablet composition of Example 6, and then after a washout period, the dogs each received a 200 mg dose of celecoxib in the form of a commercial Celebrex® 200 mg capsule,
25 which contains celecoxib entirely in crystalline form. Blood plasma was collected


WO 01/42221 PCT/USOO/32435
pre-dose and at 0.25, 0.5, 0.75, 1,1.5, 2, 3, 5, 8 and 24 hours post-dose. Celecoxib concentrations in plasma were measured using liquid chromatography/mass spectrometry. Cmax, Tmax and AUC (area under the curve, a measure of total bioavailability) were calculated from the data in accordance with standard procedure 5 in the art. Mean results for all dogs are shown in Table 3.
The tablet of Example 6 prepared from amorphous celecoxib exhibited a significantly greater Cmax, (maximum blood plasma concentration), a comparable Tmax, and a significantly greater AUC than the capsule formulated from crystalline celecoxib. As a measure of relative onset time, the time taken for the tablet of the 10 invention to reach a plasma concentration equal to the Cmax, of the crystalline celecoxib capsule was only 0.5 hour, by comparison with 1.2 hours (the Tmax for the crystalline celecoxib capsule).


WE CLAIM:
1. A process for preparing a celecoxib drug substance, the process
comprising:

(a) melting! celecoxib;
(b) rapidly cooling; the resulting melted celecoxib to form a celecoxib
drug substance wherein the celecoxib is present, in at least a
detectable amount, in amorphous form; and optionally

(c) grinding the celecoxib drug substahce to form a celecoxib. drug
substance powder.
2. The process as claimed in claim 1 wherein said melting step (a), comprises heating the celecoxib in an oven at about 150°C to about 1800C.
3. The process as claimed in any of. claim 1 or claim 2 wherein said cooling step (b) comprises immersing a container holding said melted
. celecoxib in;liquid nitrogen.
4. The process as claimed in claim 1 to 3 wherein the optional grinding
step (c) comprises grinding the celecoxib drug substance in a mortar and pestle..
5. The. processes claimed in any of Claims-1 to; 4 wherein the optional
grinding step (c) comprises grinding: the celecoxib drug, substance in
a mill
6: The process as claimed in Claim 5 wherein said mill is a media mill.
'
7. A pharmaceutical composition comprising (a), amorphous, celecoxib
or a celecoxib drug substance prepared by the process as claimed in
any of claims. 1 to 6, in a total celecoxib dosage amount of about 10
mg to abou. 100 mg, and (b) one or more pharmaceutically
acceptable excipients.
8. A process, for preparing a pharmaceutical composition as claimed in claim 7, the process comprising

(a) blending amorphous celecoxib, a celecoxib drug substance, with
one or more excipients to form a blend; and
(b) tableting or encapsulating the blend to form celecoxib tablets or
capsules respectively.

9. The process as claimed in Claim 8 comprising granulating the blend
to form a granulate prior to tableting or encapsulating.

10. The process as claimed in Claim 9 wherein granulating is performed
by wet granulation to form a wet granulate, and wherein the wet
granulate is dried prior to tableting or encapsulating.
Dated 04th day of September 2001
11(RANJNA MEHTA DUTT)
OF REMFRY & SAGAR ATTORNEY FOR THE APPLICANTS

Documents:

abstract1.jpg

in-pct-2001-01053-mum-cancelled pages(24-04-2006).pdf

in-pct-2001-01053-mum-cancelled pages(24-4-2006).pdf

in-pct-2001-01053-mum-claims(5-9-2001).pdf

in-pct-2001-01053-mum-claims(complete)-(5-9-2001).pdf

in-pct-2001-01053-mum-claims(granted)-(1-11-2006).pdf

in-pct-2001-01053-mum-claims(granted)-(24-04-2006).doc

in-pct-2001-01053-mum-claims(granted)-(24-04-2006).pdf

in-pct-2001-01053-mum-correspondence(24-04-2006).pdf

in-pct-2001-01053-mum-correspondence(26-9-2005).pdf

in-pct-2001-01053-mum-correspondence(ipo)-(01-11-2006).pdf

in-pct-2001-01053-mum-correspondence(ipo)-(22-12-2006).pdf

IN-PCT-2001-01053-MUM-CORRESPONDENCE(IPO)-(30-8-2005).pdf

in-pct-2001-01053-mum-description(complete)-(5-9-2001).pdf

in-pct-2001-01053-mum-description(granted)-(1-11-2006).pdf

in-pct-2001-01053-mum-drawing(24-04-2006).pdf

in-pct-2001-01053-mum-drawing(5-9-2001).pdf

in-pct-2001-01053-mum-drawing(complete)-(5-9-2001).pdf

in-pct-2001-01053-mum-drawing(granted)-(1-11-2006).pdf

in-pct-2001-01053-mum-form 1(05-09-2001).pdf

in-pct-2001-01053-mum-form 19(06-12-2004).pdf

in-pct-2001-01053-mum-form 1a(24-04-2006).pdf

in-pct-2001-01053-mum-form 2(5-9-2001).pdf

in-pct-2001-01053-mum-form 2(complete)-(5-9-2001).pdf

in-pct-2001-01053-mum-form 2(granted)-(1-11-2006).pdf

in-pct-2001-01053-mum-form 2(granted)-(24-04-2006).doc

in-pct-2001-01053-mum-form 2(granted)-(24-04-2006).pdf

in-pct-2001-01053-mum-form 2(title page)-(5-9-2001).pdf

in-pct-2001-01053-mum-form 2(title page)-(complete)-(5-9-2001).pdf

in-pct-2001-01053-mum-form 2(title page)-(granted)-(1-11-2006).pdf

in-pct-2001-01053-mum-form 3(05-09-2001).pdf

in-pct-2001-01053-mum-form 3(24-04-2006).pdf

in-pct-2001-01053-mum-form 4(23-02-2006).pdf

in-pct-2001-01053-mum-form 5(24-04-2006).pdf

in-pct-2001-01053-mum-form 5(5-9-2001).pdf

in-pct-2001-01053-mum-form-pct-isa-210(05-09-2001).pdf

in-pct-2001-01053-mum-power of attorney(24-04-2006).pdf

in-pct-2001-01053-mum-power of authority(24-4-2006).pdf

in-pct-2001-01053-mum-specification(amanded)-(5-9-2001).pdf

in-pct-2001-01053-mum-specification(amended)-(24-4-2006).pdf

in-pct-2001-01053-mum-wo international publication report(26-9-2005).pdf


Patent Number 203391
Indian Patent Application Number IN/PCT/2001/01053/MUM
PG Journal Number 19/2007
Publication Date 11-May-2007
Grant Date 01-Nov-2006
Date of Filing 05-Sep-2001
Name of Patentee PHARMACIA CORPORATION
Applicant Address P O BOX 5110, CHICAGO, ILLINOIS 60680,
Inventors:
# Inventor's Name Inventor's Address
1 MICHEL J. HAGEMAN 5262 south 12th street, portage, michigan 49024
2 SIARONG HE 7000 PORTAGE ROAD, KALAMAZOO, MICHIGAN 49001,
3 BRIAN R. ROHRS 9346 ARROWHEAD DRIVE, W.SCOTTS, MICHIGAN 49088
4 TUGRUL T. KARARLI 8335 N. KILDARE, SKOKIE, ILLINOIS 60076
5 LESLEY A. MACKIN 1735 CHICAGO AVENUE, EVANSTON, ILLINOIS 60201
6 PATRICIA J. MIYAKE 212 WEST LAKE SHORE DRIVE, TOWER LAKES, ILLINOIS 60010,
7 KEVIN J. STEFANSKI 2924 KENSINGTON DRIVE, KALAMAZOO, MICHIGAN 49008
PCT International Classification Number N/A
PCT International Application Number N/A
PCT International Filing date 2000-12-06
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 1 2000-12-01 U.S.A.
2 60/169,856 1999-12-08 U.S.A.