The present invention relates to granules containing pirfenidone and a sugar alcohol, and, furthermore, to the use of the granules for the preparation of an immediate-release tablet or capsule.
BACKGROUND OF INVENTION
Pirfenidone is marketed under the tradename Esbriet® in the form of film-coated tablets, which contain 267, 534 or 801 mg pirfenidone, or as a hard capsule containing 267 mg pirfenidone, for the treatment of idiopathic pulmonary fibrosis (IPF). The recommended daily maintenance dosage of Esbriet® is 801 mg three times daily for a total of 2403 mg/day. Upon initiation of treatment, titration to the full dosage of 2403 mg/day over a 14-day period is required (days 1-7, 267 mg three times daily; days 8-14, 534 mg three times daily; days 15 onward, 801 mg three times daily).
The Esbriet® tablets and capsule provide for an immediate-release of the drug. The capsule contains, besides the drug, microcrystalline cellulose, croscarmellose sodium, povidone and magnesium stearate, while the tablet contains, in the core, the drug, microcrystalline cellulose, colloidal anhydrous silica, povidone K30, croscarmellose sodium and magnesium stearate. Pirfenidone is a crystalline powder and sparingly soluble in 1.0 N HO, water and l.ONNaOH; the dissolution in water is pH independent (19 mg/ml at 25°C). Pirfenidone has poor flowability characteristics, and in view of the fact that the Esbriet® capsule and tablets contain high concentrations of pirfenidone, in order to provide a tablet and capsule size that is suitable for oral administration, the state of the art focuses on improving the processability of the drug. The Esbriet® capsule and tablets are prepared by using wet-granulation.
EP-A-1 356 816 describes the preparation of a tablet containing 200 mg pirfenidone, in which the drug, lactose and a part of the contained carmellose calcium is subjected to wet-granulation using an aqueous solution of hydroxypropyl cellulose as a granulating fluid, followed by mixing the obtained granules with the remaining part of carmellose calcium and magnesium stearate, and subjecting the mixture to

compression. Subsequently, the tablet core is coated with a film. This tablet is marketed in Japan under the tradename Pirespa® for the treatment of IPF.
It is stated in WO 2007/038315 that the Pirespa® tablet core contains about 70 % pirfenidone and that a higher drug content would be desirable. WO 2007/038315 relates to a capsule formulation containing 70-95 % pirfenidone and 5-30 % pharmaceutical excipients. This application relates to the Esbriet® capsule, which may be prepared by milling a mixture of croscarmellose sodium, microcrystalline cellulose and pirfenidone, and subjecting the obtained mixture to wet-granulation using an aqueous povidone solution as granulating liquid. Subsequently, the granules are mixed with an additional amount of croscarmellose sodium and magnesium stearate, and, thereafter, the obtained mixture is filled into a capsule.
EP-A-2 735 306 discloses an extended-release tablet containing pirfenidone. The tablet is prepared by direct compression, in which pirfenidone and silicon dioxide are mixed in order to improve the flowability of the drug, followed by adding microcrystalline cellulose, low-viscosity hydroxypropyl methylcellulose (HPMC), high-viscosity HPMC and sodium stearyl fumarate, and subjecting the obtained mixture to compression. The low and high-viscosity HPMCs form the extended-release matrix, whereby the microcrystalline cellulose improves the tablet hardness.
WO 2017/172602 relates to the Esbriet® tablet. It is stated in the application that the particle size of pirfenidone can vary between the suppliers and that is was found that these particle size variations affect the hardness of the tablet. However, the particle size distribution of pirfenidone has no influence on the drug release characteristics, if the Dv90 value is adjusted to 50-150 |im. Rather, the drug release characteristics depend on the solid fraction of the tablet (the ratio of the tablet's apparent density and true density): the higher the solid fraction, the longer the disintegration time.
The tablet is prepared by subjecting pirfenidone, a filler (preferably microcrystalline cellulose) and a glidant (preferably silica) to wet-granulation using an aqueous binder (preferably povidone) solution. The obtained granules are subsequently mixed with a disintegrant (preferably croscarmellose sodium), a lubricant (preferably magnesium

stearate) and a glidant (preferably silica). Finally, the obtained mixture is subjected to compression, and the obtained tablet core is film-coated. The intragranular glidant is required to improve the flowability of pirfenidone.
OBJECTOF THE INVENTION
It was an objective of the present invention to provide an immediate-release tablet or capsule for oral administration containing pirfenidone, which may contain the drug in a high concentration of at least 70 % by weight and which can be prepared from a drug formulation that exhibits good flow properties. This objective is attained by the subject matter as defined in the claims.
SUMMARY OF THE INVENTION
The present invention relates to granules containing pirfenidone and a sugar alcohol, and, furthermore, to the use of the granules for the preparation of an immediate-release tablet or capsule.
DETAILED DESCRIPTION
The unit dosage form of the present invention is an immediate-release tablet or an immediate-release capsule for oral administration; preferably the tablet is a film-coated tablet. These unit dosage forms contain granules containing pirfenidone, a sugar alcohol, optionally a disintegrant and optionally a further pharmaceutical excipient, wherein the weight ratio of the sugar alcohol to pirfenidone is 2 : 100 to 30 : 100. It was found that a glidant is not required in order to improve the flowability of pirfenidone, if the powder mixture to be subjected to granulation contains a sugar alcohol. Thus, in a preferred embodiment of the present invention, the granules do not contain a glidant.
It is preferred that the weight ratio of the sugar alcohol to pirfenidone is 3 : 100 to 25 : 100, wherein the granules to be filled into the capsule contain the sugar alcohol and pirfenidone preferably in a weight ratio of 5 : 100 to 15 : 100, more preferred 8 : 100 to 12 : 100 (sugar alcohol: pirfenidone).

The further pharmaceutical excipient, optionally contained in the granules of the present invention, may be selected from a binder and a filler. It is preferred that the granules contained in the tablet of the present invention are prepared by wet-granulation, in which case a binder is preferably contained in the granules. The preferred method for preparing the granules contained in the capsule of the present invention is dry-granulation, in which case no binder is required. It was found that it is difficult to fill granules prepared by wet-granulation into size "1" capsules, but larger capsules are less convenient to the patient upon swallowing. It is preferred that the granules of the present invention consist of pirfenidone, a disintegrant, a sugar alcohol, and optionally a binder and optionally a filler.
Typically, the sugar alcohol contained in the granules of the present invention is a C4-12 sugar alcohol, such as erythritol, xylitol, sorbitol, mannitol, maltitol, lactitol and isomalt. The preferred sugar alcohol contained in the granules of the tablet is mannitol, while the preferred sugar alcohol contained in the granules of the capsule is isomalt.
It is desired that the tablet core has a minimum hardness in order to remain intact through post-compaction processes, such as coating, transport/handling and packaging. The tablet core hardness for the 267 mg strength should be at least 60 N, and, for the 543 mg and 801 mg strengths, a hardness of at least 90 N and at least 120 N, respectively, is desired. It was found that a desired minimum tablet core hardness, and thus the tablet hardness, could not be achieved if a sugar alcohol is not present in the granules.
Examples of disintegrants include croscarmellose sodium, sodium starch glycolate, polyvinylpolypyrrolidone (crospovidone), carmellose sodium, carmellose potassium, polacrilin sodium, polacrilin potassium, silicified microcrystalline cellulose and low-substituted hydroxypropyl cellulose, whereby croscarmellose sodium is preferred.
The further pharmaceutical excipient contained in the tablet and capsule of the present invention may be selected from fillers, binders, glidants and lubricants.

Examples of fillers include microcrystalline cellulose, calcium hydrogen phosphate (anhydrous or dihydrate), lactose (anhydrous or monohydrate), dextrose, calcium carbonate, starch, pregelatinized starch, magnesium carbonate, silicified microcrystalline cellulose and powder cellulose, whereby microcrystalline cellulose is preferred.
Examples of binders include hydroxymethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose (Hypromellose), guar gum, maltodextrin, corn starch, polyvinylpyrrolidone (povidone) and vinylpyrrolidone/vinyl acetate copolymer (copovidone), wherein povidone is preferred.
Examples of glidants include silicon dioxide (silica), e.g. fumed (colloidal) silicon dioxide, talc and magnesium silicate, wherein silicon dioxide is preferred.
Examples of lubricants include magnesium stearate, calcium stearate, zinc stearate, stearic acid, sodium stearyl fumarate and glyceryl dibehenate, wherein the capsule preferably contains magnesium stearate and the tablet preferably contains sodium stearyl fumarate.
The capsule of the present invention is preferably prepared by a dry-granulation process comprising the steps:
i) preparing a mixture containing pirfenidone, a sugar alcohol, optionally a
first disintegrant and optionally a further first pharmaceutical excipient, ii) subjecting the mixture obtained in step (i) to compaction, iii) milling the compacted material obtained in step (ii) to obtain granules,
wherein the weight ratio of the sugar alcohol to pirfenidone in the
obtained granules is 2 : 100 to 30 : 100, iv) optionally mixing the granules with a second disintegrant and/or a further
second pharmaceutical excipient, and v) filling the granules obtained in step (iii) or the mixture obtained in
step (iv) into a capsule.

The dry-granulation process may be performed by roller compaction or slugging, wherein roller compaction is preferred. The further second pharmaceutical excipient is preferably a lubricant.
In a preferred embodiment of the process of the present invention, the capsule contains a mixture consisting of granules made from pirfenidone, a disintegrant and a sugar alcohol, and a lubricant, and the process comprises the steps:
i) preparing a mixture consisting of pirfenidone, a disintegrant and a sugar
alcohol, ii) subjecting the mixture obtained in step (i) to compaction, iii) milling the compacted material obtained in step (ii) to obtain granules, iv) mixing the granules obtained in step (iii) with a lubricant, and v) filling the mixture obtained in step (iv) into a capsule.
Preferably, the disintegrant is croscarmellose sodium, the sugar alcohol is isomalt and the lubricant is magnesium stearate.
The optionally film-coated tablet of the present invention, which contains pirfenidone, a sugar alcohol, optionally a disintegrant and optionally a further pharmaceutical excipient, is preferably prepared by wet-granulation comprising the steps:
i) preparing a mixture containing pirfenidone, a sugar alcohol, optionally a
first disintegrant and optionally a further first pharmaceutical excipient,
ii) subjecting the mixture obtained in step (i) to wet granulation using an aqueous granulating liquid, wherein the weight ratio of the sugar alcohol to pirfenidone in the obtained granules is 2 : 100 to 30 : 100,
iii) optionally mixing the granules obtained in step (ii) with a second disintegrant and/or a further second pharmaceutical excipient,
iv) subjecting the granules obtained in step (ii) or the mixture obtained in step (iii) to compression to obtain the tablet.

It is preferred that the first further pharmaceutical excipient used in method step (i) is a filler, while the second pharmaceutical excipient used in method step (iii) may be selected from a filler, a glidant and a lubricant. It is preferred that, for the wet-granulation step (ii), an aqueous granulating liquid containing a binder, which is 5 preferably a binder-containing aqueous solution, is used.
According to a preferred embodiment of the present invention, the tablet or the tablet core consists of a mixture consisting of granules made from pirfenidone, a first disintegrant, a sugar alcohol, a binder and optionally a first filler, a second 10 disintegrant, a second filler, a glidant and a lubricant, wherein the process comprises the steps:
i) preparing a mixture consisting of pirfenidone, a first disintegrant, a sugar
15
alcohol and optionally a first filler, ii) subjecting the mixture obtained in step (i) to wet granulation using an
aqueous binder-containing solution as granulating liquid, iii) mixing the granules obtained in step (ii) with a second disintegrant, a
second filler, a glidant and a lubricant, iv) subjecting the mixture obtained in step (iii) to compression to obtain the
20
tablet.
The first and second disintegrant may be identical. In a preferred embodiment of the process of the present invention, the first and second disintegrant is croscarmellose sodium, the sugar alcohol is mannitol, the optionally contained first filler and the 25 second filler are microcrystalline cellulose, the glidant is silicon dioxide and the lubricant is sodium stearyl fumarate.
The compressed tablets may optionally be coated with a film coating polymer. Examples of polymers for film coating are polyvinyl alcohol, hydroxypropyl 30 methylcellulose, hydroxypropyl cellulose, whereby polyvinyl alcohol is preferred. The film coating layer may further comprise plasticizer and colorants. Preferably the film coating layer comprises polyvinyl alcohol, titanium dioxide, macrogol (PEG), talc and one or more colorants (e.g. iron oxide). Ready made commercially available film
8

coating systems containing polyvinyl alcohol polymers, like Opadry® Clear 06F590004, Opadry® Pink OY-S-34907, Opadry® II Purple 85F500082, Opadry® II Purple 85F500083, Opadry® Yellow 85F520311, Opadry® II Brown 85F565071 and Opadry® Orange 85F530178, can be used. 5
It was found that the particle size of pirfenidone affects the hardness of the tablet: the higher the particle size of pirfenidone, the lower the hardness of the tablet. It was found that the desired hardness could not be achieved if the utilized pirfenidone has a particle size distribution Dv90 of more than 400 µm. Thus, the particle size distribution 10 of pirfenidone is preferably adjusted to Dv90=50-300 µm, preferably 100-200 µm (determined by using Mastersizer 2000).
The optionally film-coated tablet and capsule of the present invention preferably contains pirfenidone in an amount of at least 70 % by weight. Preferably the capsule of 15 the present invention comprises 80-90 % by weight of pirfenidone, 2-10 % by weight of a disintegrant, 5-15 % by weight of a sugar alcohol, 0-10 % by weight of a binder and 0.1-5 % by weight of a lubricant, for example, 84.8 % by weight of pirfenidone, 6.0 % by weight of a disintegrant, 8.9 % by weight of a sugar alcohol and 0.3 % by weight of a lubricant. Preferably the tablet core of the present invention comprises 85-20 90 % by weight of pirfenidone, 1-10 % by weight of a disintegrant, 1-10 % by weight of a sugar alcohol, 0.5-7 % by weight of a binder, 1-10 % by weight of a filler, 0.1-5 % by weight of a lubricant and 0.1-5 % by weight of a glidant, for example, 87 % by weight of pirfenidone, 2.2 % by weight of a disintegrant, 3.2 % by weight of a sugar alcohol, 2.2 % by weight of a binder, 4.5 % by weight of a filler, 0.6 % by weight of a 25 lubricant and 0.3 % by weight of a glidant.
The following examples are intended to further illustrate the present invention.
Examples
30 In the examples, crystalline pirfenidone having a particle size distribution of Dv90=100-200 µm was used. Particle size distribution was determined by using laser diffraction with a Mastersizer 2000 (by Malvern Intr. Ltd.) in dry dispersion mode. Dv90 corresponds to the particle size at 90% of the cumulative volume distribution.
9

The dissolution tests were performed according to general chapter 〈711〉 DISSOLUTION of USP40–NF35 and the US FDA recommended dissolution method for pirfenidone capsule: apparatus II (paddle; with sinker in case of capsules), speed: 50 rpm, medium: deionized water, volume: 1000 ml, sampling times: 5, 10, 15, 20, 30, 5 and 45 min as well as 60 min.
Bulk density and tapped density were determined according to general chapter 〈616〉 BULK DENSITY AND TAPPED DENSITY OF POWDERS of USP40–NF35. Hardness was determined according to European Pharmacopeia 9.2, 2.9.8.
10 Disintegration time was determined according to general chapter 〈701〉 DISINTEGRATION of USP40–NF35. Friability was determined according to general chapter 〈1216〉 TABLET FRIABILITY of USP40–NF35. Compressibility Index and Hausner’s Ratio were calculated from tapped and bulk density (Compressibility Index = (tapped density - bulk density) / tapped density * 100; Hausner’s Ratio = tapped
15 density / bulk density).
Examples 1-4 (capsules)

Ingredients Ex. 1 Ex. 2 Ex. 3 Ex. 4
Stage-A (Blending & Compaction) mg/cap
Pirfenidone 267.267 267.267 267.267 267.000
Croscarmellose Sodium (AC-DI-SOL®) 28.000 16.000 22.000 19.000
Isomalt (Galen IQ 721) 27.733 27.733 27.733 28.000
Stage- B (Lubrication)
Magnesium Stearate (Ligamed® MF-2-V) 1.000 1.000 1.000 1.000
Fill weight (mg) 324.000 312.000 318.000 315.000
Stage-C (Encapsulation)
Hard Gelatin Capsule Shells (SIZE"1") 75.000 75.000 75.000 75.000
Capsule weight (mg) 399.000 387.000 393.000 390.000

Physical Parameters (Blend)
Dv90 of pirfenidone drug substance 145 145 145 145
10

Bulk Density (g/ml) 0.556 0.573 0.548 0.553
Tapped Density (g/ml) 0.798 0.796 0.807 0.798
Compressibility Index (%) 30.357 28.000 32.099 30.702
Hausner’s Ratio 1.436 1.389 1.473 1.443
Physical Parameters (Capsules)
Average Lock Length (mm) 18.98 18.95 19.01 19.00
Average Weight (mg) 399.8 386.5 393.7 390.6
Disintegration time (min) 2-3 min 2-3 min 2-3 min 2-3 min
Procedure:
The dispensed quantities of stage A materials are sifted through a suitable sieve (e.g. #30 mesh) and blended for a suitable time (e.g. 5 minutes) in a blender. The sifted 5 materials are compacted using roller compactor with suitable set of parameters. The compacts are milled to the required sized granules (e.g. approx. 700 µm). Milled granules were sifted through a suitable sieve (e.g. #25 mesh) and the sized granules are blended with extra granular materials of stage B, in blender for a suitable time (for example 5 minutes). The lubricated granules are filled into size 1 hard gelatin 10 capsules.

Example Mean Cumulative % Labelled Amount Dissolved
[%]

5 min 10 min 15 min 20 min 30 min 45 min 60 min
Esbriet® 267 mg
capsules
(Lot no. 3056759) 58 78 84 90 98 102 103
Example 1 64 81 91 96 100 101 101
Example 2 56 75 87 93 99 101 102
Example 3 60 78 88 93 99 101 101
Example 4 50 66 76 84 93 98 99
11

Examples 5-7 (tablets)

Ingredients Ex. 5 Ex. 6 Ex. 7
Stage-A (Sifting & Blending) mg/tab
Pirfenidone 810.388 803.007 803.007
Mannitol (Pearlitol® SD200) 195.612 115.993 104.993
Sodium Starch Glycolate (Explotab®) 15.000 - -
Stage-B (Binder Solution)
Hypromellose
(Methocel® E15 Premium LV) 18.000 24.000 28.000
Water, Purified q.s. q.s. q.s.
Stage-C (Blending & Lubrication)
Sodium Starch Glycolate (Explotab®) 9.000 20.000 16.000
Silica Colloidal Anhydrous (Aerosil® 200) 6.000 6.000 6.000
Sodium Stearyl Fumarate - 6.000 6.000
Magnesium Stearate 6.000 - -
Core Tablet Weight (mg) 1060.000 975.000 964.000
Stage-D (Coating)
Opadry® Clear 06F590004 30.000 25.000 25.000
Water, Purified q.s. q.s. q.s.
Coated Tablet Weight (mg) 1090.000 1000.000 989.000
Procedure:
The stage-A materials were sifted through a suitable sieve (e.g. #30 mesh), loaded into 5 a rapid mixer granulator and mixed for a suitable time. The binder solution was prepared by dispersing binder of stage-B into the purified water. The binder solution was slowly added into the rapid mixer granulator to obtain a wet mass. The wet mass was dried in Fluidized bed drier. The dried granules were milled. The sized granules were sifted through a suitable sieve (e.g. #25 mesh) and blended with sifted extra 10 granular materials of Stage-C. The resulting mixture was compressed to (core) tablets in a tabletting machine and film-coated (using stage-D film coating) in an automated coating machine with perforated pan.
12

Blend Parameters Ex. 5 Ex. 6 Ex. 7
Bulk Density (g/ml) 0.468 0.451 0.490
Tapped Density (g/ml) 0.570 0.552 0.610
Compressibility Index (%) 17.895 18.29 21.428
Hausner’s Ratio 1.218 1.223 1.273

Tablet Core Parameters Ex. 5 Ex. 6 Ex. 7
Tablet Weight (mg) 1060-1064 965-975 960-970
Hardness (Newtons) 150-156 145-155 140-150
Thickness (mm) 6.39-6.41 6.00-6.10 6.60-6.70
Disintegration Time (min) 2 min 0 sec 2 min 05 sec 3 min 40 sec
Friability (%) 0.03 0.061 0
Coated Tablet Parameters Ex. 5 Ex. 6 Ex. 7
Tablet Weight (mg) 980-990 980-990 980-990
Thickness (mm) 6.80-6.90 6.70-6.80 6.80-6.90
Disintegration Time (min) 7 min 38 sec 8-9 min 7 min 38 sec

Example Mean Cumulative % Labelled Amount Dissolved [%]

5 min 10 min 15 min 20 min 30 min 45 min 60 min
Example 5 59 91 96 99 103 105 105
Example 6 59 86 92 95 96 97 97
Example 7 44 75 90 95 99 101 102
Examples 8 and 9 (tablets)

Ingredients Ex. 8 Ex. 9
Stage-A (Dispensing & Blending) mg/tab
Pirfenidone 802.605 803.893
Mannitol (Pearlitol® 200 SD) 106.395 105.107
Sodium Starch Glycolate - 8.000
13

(Explotab®)
Stage-B (Binder Solution)
Povidone (Plasdone® K-29/32) 25.000 25.000
Water, Purified q.s. q.s.
Stage-C (Blending & Lubrication)
Sodium Starch Glycolate (Explotab®) 16.000 8.000
Silica, Colloidal Anhydrous (Aerosil® 200 Pharma) 6.000 6.000
Sodium Stearyl Fumarate 6.000 6.000
Core tablet weight (mg) 962.000 962.000
Stage-D (Coating)
Opadry® Pink OY-S-34907 25.000 25.000
Water, Purified q.s. q.s.
Coated Tablet weight (mg) 987.000 987.000
Procedure:
The stage-A materials were sifted through a suitable sieve (e.g. #30 mesh), loaded into a rapid mixer granulator and mixed for a suitable time. The binder solution was 5 prepared by dispersing binder of stage-B into the purified water. The binder solution was slowly added into the rapid mixer granulator to obtain a wet mass. The wet granules were dried. The dried granules were milled. The sized granules were sifted through a suitable sieve (e.g. #25 mesh) and blended with sifted extra granular materials of Stage-C. The resulting mixture was compressed to (core) tablets in a 10 tabletting machine and film-coated (using stage-D film coating) in an automated coating machine with perforated pan.

Blend Parameters Ex. 8 Ex. 9
Bulk Density (g/ml) 0.526 0.490
Tapped Density (g/ml) 0.623 0.610
Compressibility Index (%) 16 21.428
14

Hausner’s Ratio 1.18 1.273

Tablet Core Parameters Ex. 8 Ex. 9
Tablet Weight (mg) 960-970 960-970
Hardness (Newtons) 140-155 160-175
Thickness (mm) - 6.55-6.65
Disintegration Time (min) 2 min 30 sec 3-4 min
Friability (%) 0 0
Coated Tablet Parameters Ex. 8 Ex. 9
Tablet Weight (mg) 980-990 980-990
Thickness (mm) - 6.70-6.80
Disintegration Time (min) 5-6 min 8-9 min

Example Mean Cumulative % Labelled Amount Dissolved [%]

5 min 10 min 15 min 20 min 30 min 45 min 60 min
Example 8 72 97 102 103 103 103 103
Example 9 33 83 98 100 100 102 101
15
Examples 10 and 11 (tablets)

Ingredients Ex. 10 Ex. 11
Stage-A (Sifting & Blending) mg/tab
Pirfenidone 803.893 801.802
Mannitol (Pearlitol® SD 200) 50.000 30.000
Microcrystalline Cellulose (Pharmacel® 101) 51.107 -
15

Croscarmellose Sodium (Ac-di-sol®) 10.000 5.000
Stage-B (Binder Solution)
Povidone (Plasdone® K-29/32) 35.000 20.000
Water, Purified q.s. q.s.
Stage-C (Blending & Lubrication)
Microcrystalline Cellulose (Pharmacel®101) - 40.198
Croscarmellose Sodium (Ac-di-sol®) 10.000 15.000
Silica, Colloidal Anhydrous (Aerosil® 200 Pharma) 3.000 3.000
Sodium Stearyl Fumarate 6.000 6.000
Core Tablet Weight (mg) 969.000 921.000
Stage-D (Coating)
Opadry® II Purple 85F500083 27.000 24.000
Water, Purified q.s. q.s.
Coated Tablet Weight (mg) 996.000 945.000
Procedure:
The stage-A materials were sifted through a suitable sieve (e.g. #30 mesh), loaded into a rapid mixer granulator and mixed for a suitable time. The binder solution was 5 prepared by dispersing binder of stage-B into the purified water. The binder solution was slowly added into the rapid mixer granulator to obtain a wet mass. The wet mass was milled and the sized granules were dried. The dried granules were sifted through a suitable sieve (e.g. #20 mesh) and blended with sifted extra granular materials of Stage-C. The resulting mixture was compressed to (core) tablets in a tabletting 10 machine and film-coated (using stage-D film coating) in an automated coating machine with perforated pan.
16

15

Blend Parameters Ex. 10 Ex. 11
Bulk Density (g/ml) 0.440 0.449
Tapped Density (g/ml) 0.551 0.592
Compressibility Index (%) 20.19 24.15
Hausner’s Ratio 1.252 1.318

Tablet Core Parameters Ex. 10 Ex. 11
Tablet Weight (mg) 966-977 917-924
Hardness (Newtons) 166-175 137-156
Thickness (mm) 6.69-6.72 6.95-7.02
Disintegration Time (min) 3 min 0 min 36 sec
Friability (%) 0.09 0
Coated Tablet Parameters Ex. 10 Ex. 11
Tablet Weight (mg) 995-1000 940-950
Thickness (mm) 6.77-6.79 7.00-7.05
Disintegration Time (min) 4-5 min 1 min

Example Mean Cumulative % Labelled Amount Dissolved [%]

5 min 10 min 15 min 20 min 30 min 45 min 60 min
Example 10 53 94 97 98 99 99 99
Example 11 93 99 100 101 102 102 103
Examples 12-15 (tablets)

Ingredients Ex. 12 267 mg Ex. 13 267 mg Ex. 14 534 mg Ex. 15 801 mg
Stage-A (Sifting) mg/tab
Pirfenidone 267.000 267.964 534.000 801.000
17

Mannitol (Pearlitol® SD 200) 10.000 34.369 20.000 30.000
Croscarmellose Sodium 1.667 - 3.334 5.000
Sodium Starch Glycolate (Primogel®) - 2.667 - -
Stage-B (Binder Solution)
Povidone (Plasdone® K-29/32) 6.667 8.333 13.334 20.000
Water, Purified q.s. q.s. q.s. q.s.
Stage-C (Blending & Lubrication)
Microcrystalline Cellulose (Comprecel/ Pharmacel® PH 101) 13.666 - 27.332 41.000
Sodium Starch Glycolate (Primogel®) - 2.667 - -
Croscarmellose Sodium 5.000 - 10.000 15.000
Silica, Colloidal Anhydrous 1.000 2.000 2.000 3.000
Sodium Stearyl Fumarate 2.000 2.000 4.000 6.000
Core Tablet Weight (mg) 307.000 320.000 614.000 921.000
Stage-D (Coating)
Opadry® Yellow 85F520311 8.000 - - -
Opadry® II Brown 85F565071 - 8.000 - -
Opadry® Orange 85F530178 - - 16.000 -
Opadry® II Purple 85F500083 - - - 24.000
Water, Purified q.s. q.s. q.s. q.s.
Coated Tablet Weight (mg) 315.000 328.000 630.000 945.000
18

Procedure:
The stage-A materials were sifted through a suitable sieve (e.g. # 30 mesh), loaded into a rapid mixer granulator and mixed for a suitable time (e.g. 5 minutes). The binder solution was prepared by dispersing binder of stage-B into the purified water under 5 stirring. The binder solution was slowly added into the rapid mixer granulator to obtain a wet mass. The wet mass was milled through a 6350 µm screen and the wet granules were dried. The dried granules were sifted through a suitable sieve (e.g. # 20 mesh) and retains collected were milled through a 1016 µm screen. The sized granules blended with extra granular materials of Stage-C (sifted in advance through a suitable
10 sieve, e.g. # 30 mesh). The resulting mixture was compressed to (core) tablets in a tabletting machine. The coating solution was prepared by dispersing the coating material (stage-D) directly in to the purified water under stirring (20% w/w solids) and stirring was continued for a suitable time (e.g. 45 minute). The (core) tablets were coated with the coating solution by using an automated coating machine with
15 perforated pan.

Blend Parameters Ex. 12 Ex. 13 Ex. 14 Ex. 15
Dv90 of pirfenidone drug substance 145 150 145 145
Bulk Density (g/ml) 0.449 0.497 0.449 0.424
Tapped Density (g/ml) 0.592 0.644 0.592 0.538
Compressibility Index (%) 24.15 22.82 24.15 21.212
Hausner’s Ratio 1.318 1.295 1.318 1.269

Tablet Core Parameters Ex. 12 Ex. 13 Ex. 14 Ex. 15
Tablet Weight (mg) 307 320 614.5 923.5
Hardness (Newtons) 90 95-105 110 166
Thickness (mm) 5.30 5.06 6.82 6.93
Disintegration Time (min) 30 sec 2-3 34 sec 2
Friability (%) 0.09 0 0 0
19

Coated Tablet Parameters Ex. 12 Ex. 13 Ex. 14 Ex. 15
Tablet Weight (mg) 315 325-331 630.5 947.5
Thickness (mm) 5.35 5.13 6.83 7.00
Disintegration Time (min) 1 5-6 1 3

Example Mean Cumulative % Labelled Amount Dissolved [%]

5 min 10 min 15 min 20 min 30 min 45 min 60 min
Example 12 90 97 101 102 102 103 103
Example 13 56 92 98 100 101 101 101
Example 14 93 97 100 101 101 102 102
Example 15 81 91 93 95 97 99 100
Comparative Example 1 (capsule)

Ingredients Comp. Ex. 1
Stage – A (Dry mix) mg/tab
Pirfenidone 267.481
Microcrystalline Cellulose (Avicel® PH 102) 23.519
Croscarmellose Sodium (Ac-Di-Sol® SD 711) 26.500
Stage – B (Granulation)
Povidone (Plasdone® K 29/32) 6.000
Water, Purified q. s.
Stage – C (Blending & Lubrication)
Magnesium Stearate 1.500
Fill weight (mg) 325.000
Stage – D (Encapsulation)
Hard Gelatin Capsule Shells (Size “1”) 96.000
Capsule weight (mg) 421.000

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Physical Parameters (granules)
Bulk Density (g/ml) 0.422
Tapped Density (g/ml) 0.552
Compressibility Index (%) 23.040
Hausner’s Ratio 1.305
Procedure:
The stage-A materials were sifted through a suitable sieve (e.g. #30 mesh), loaded into a rapid mixer granulator and mixed for a suitable time. The binder solution was 5 prepared by dispersing binder of stage-B into the purified water. The binder solution was slowly added into the rapid mixer granulator to obtain a wet mass. The wet granules were dried. The dried granules were milled. The sized granules were sifted through a suitable sieve (e.g. #30 mesh) and blended with sifted extra granular materials of Stage-C for a suitable time. The lubricated blend could not be filled into 10 size “1” capsules. Thus, the dry-granulation process is preferred.
Comparative Examples 2-4 (tablets)

Ingredients Comp. Ex. 2 Comp. Ex. 3 Comp. Ex. 4
Stage – A (Blending) mg/tab
Pirfenidone 268.018 268.018 268.018
Mannitol (Pearlitol® SD 200) 42.982 64.982 -
Dicalcium Phosphate Dihydrate - - 67.982
Hypromellose
(Methocel® E5 Premium LV) 6.000 - 6.000
Xanthan Gum - 7.000 -
Sodium Starch Glycolate (Explotab®) 6.000 8.000 6.000
Sodium Stearyl Fumarate 2.000 2.000 -
Magnesium Stearate - - 2.000
Core tablet weight (mg) 325.000 350.000 350.000
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Procedure:
The dispensed quantities were sifted through suitable sieve (e.g. #30 mesh). The sifted materials were blended for a suitable time in a blender. The resulting mixture was compressed to core tablets on a tabletting machine. 5
The desired hardness (above 60 N) could not be achieved. The direct compression process failed to give the desired hardness for the tablets.
10 Comparative Examples 5 and 6 (tablets)

Ingredients Comp. Ex. 5 Comp. Ex. 6
Stage – A (Sifting & Blending) mg/tab
Pirfenidone 268.018 268.018
Dicalcium Phosphate Dihydrate (DICOFOS® D014) 67.982 67.982
Sodium Starch Glycolate 5.000 5.000
Stage-B (Binder Solution)
Hypromellose (Methocel® E5 Premium LV) 6.000 6.000
Water, Purified q.s. q.s.
Stage-C (Blending & Lubrication)
Sodium Starch Glycolate 3.000 3.000
Silica, Colloidal Anhydrous (Aerosil® 200 Pharma) - 1.800
Magnesium Stearate 2.000 2.000
Core tablet weight (mg) 352.000 353.800
Procedure:
The stage-A materials were sifted through a suitable sieve (e.g. #30 mesh), loaded into a rapid mixer granulator and mixed for a suitable time. The binder solution was 15 prepared by dispersing binder of stage-B into the purified water. The binder solution was slowly added into the rapid mixer granulator to obtain a wet mass. The wet mass was dried in fluidized bed drier. The dried granules were sifted through a suitable sieve (e.g. #25 mesh) and retains were milled. The sized granules were blended with
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sifted extra granular materials of Stage-C. The resulting mixture was compressed to core tablets in a tabletting machine.
The desired hardness (above 60 N) could not be achieved without a sugar alcohol 5 present in the granules. Maximum hardness achieved for both the batches was 45 N.
Comparative Examples 7-8 (tablets)

Ingredients Comp. Ex. 7 Comp. Ex. 8
Stage-A (Dispensing & Blending) mg/tab
Pirfenidone 803.007 803.893
Microcrystalline Cellulose (Comprecel® M 102 D) 104.993 103.107
Croscarmellose Sodium (Ac-Di-sol®) - 8.000
Stage-B (Binder solution)
Povidone (Plasdone® K-29/32) 28.000 35.000
Water, Purified q.s. q.s.
Stage-C (Blending & Lubrication)
Croscarmellose Sodium (Ac-Di-sol®) 16.000 8.000
Silica, Colloidal Anhydrous (Aerosil® 200 Pharma) 6.000 6.000
Sodium Stearyl Fumarate 6.000 6.000
Core tablet weight (mg) 964.000 970.000
10 Procedure:
The stage-A materials were sifted through a suitable sieve (e.g. #30 mesh), loaded into a rapid mixer granulator and mixed for a suitable time. The binder solution was prepared by dispersing binder of stage-B into the purified water. The binder solution was slowly added into the rapid mixer granulator to obtain a wet mass. The wet mass
15 was dried in fluidized bed drier. The dried granules were sifted through a suitable
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sieve (e.g. #25 mesh) and retains were milled. The sized granules were blended with sifted extra granular materials of Stage-C. The resulting mixture was compressed to core tablets in a tabletting machine.

Blend Parameters Comp. Ex.
7 Comp. Ex. 8
Bulk Density (g/ml) 0.411 0.414
Tapped Density (g/ml) 0.532 0.506
Compressibility Index (%) 22.727 18.293
Hausner's Ratio 1.294 1.224

Tablet Core Parameters Comp. Ex.
7 Comp. Ex. 8
Tablet Weight (mg) 960-970 970-980
Hardness (Newtons) 90-100 90-100
Thickness (mm) 6.90-7.00 6.80-6.90
Disintegration Time (min) 0 min 24 sec 0 min 50 sec
Friability (%) 0.4 3.2
The desired hardness (above 120 N) could not be achieved without a sugar alcohol present in the granules.

We claim:
Granules containing pirfenidone, a sugar alcohol, optionally a disintegrant and optionally a further pharmaceutical excipient, wherein the weight ratio of the sugar alcohol to pirfenidone is 2 : 100 to 30 : 100.
The granules according to claim 1, wherein the granules do not contain a glidant.
The granules according to claim 1 or 2, wherein the pharmaceutical excipient is selected from a binder and a filler.
The granules according to claim 3, wherein the granules consist of pirfenidone, a disintegrant, a sugar alcohol, and optionally a binder and optionally a filler.
The granules according to any one of the preceding claims, wherein the sugar alcohol is a C4_i2 sugar alcohol.
The granules according to claim 5, wherein the sugar alcohol is selected from erythritol, xylitol, sorbitol, mannitol, maltitol, lactitol and isomalt.
The granules according to claim 6, wherein the sugar alcohol is mannitol or isomalt.
The granules according to any one of the preceding claims, wherein the weight ratio of the sugar alcohol to pirfenidone is 3 : 100 to 25 : 100.
A tablet or capsule for oral administration containing the granules according to any one of the preceding claims.
Process for preparing a capsule containing pirfenidone, a sugar alcohol, optionally a disintegrant and optionally a further pharmaceutical excipient, comprising the steps:

i) preparing a mixture containing pirfenidone, a sugar alcohol, optionally a
first disintegrant and optionally a further first pharmaceutical excipient, ii) subjecting the mixture obtained in step (i) to compaction, iii) milling the compacted material obtained in step (ii) to obtain granules,
wherein the weight ratio of the sugar alcohol to pirfenidone in the obtained
granules is 2 : 100 to 30 : 100, iv) optionally mixing the granules with a second disintegrant and/or a further
second pharmaceutical excipient, and v) filling the granules obtained in step (iii) or the mixture obtained in step (iv)
into a capsule.
The process according to claim 10, wherein the compaction is a roller compaction or performed by slugging.
The process according to claim 10 or 11, wherein the further second pharmaceutical excipient is a lubricant.
The process according to claim 12, wherein the capsule contains a mixture consisting of granules made from pirfenidone, a disintegrant and a sugar alcohol, and a lubricant, comprising the steps:
i) preparing a mixture consisting of pirfenidone, a disintegrant and a sugar
alcohol, ii) subjecting the mixture obtained in step (i) to compaction, iii) milling the compacted material obtained in step (ii) to obtain granules, iv) mixing the granules obtained in step (iii) with a lubricant, and v) filling the mixture obtained in step (iv) into a capsule.
The process according to claim 13, wherein the disintegrant is croscarmellose sodium, the sugar alcohol is isomalt and the lubricant is magnesium stearate.

Process for preparing an optionally film-coated tablet containing pirfenidone, a sugar alcohol, optionally a disintegrant and optionally a further pharmaceutical excipient, comprising the steps:
i) preparing a mixture containing pirfenidone, a sugar alcohol, optionally a first disintegrant and optionally a further first pharmaceutical excipient,
ii) subjecting the mixture obtained in step (i) to wet granulation using an aqueous granulating liquid, wherein the weight ratio of the sugar alcohol to pirfenidone in the obtained granules is 2 : 100 to 30 : 100,
iii) optionally mixing the granules obtained in step (ii) with a second disintegrant and/or a further second pharmaceutical excipient,
iv) subjecting the granules obtained in step (ii) or the mixture obtained in step (iii) to compression to obtain the tablet.
The process according to claim 15, wherein the first pharmaceutical excipient is a filler.
The process according to claim 15 or 16, wherein the second pharmaceutical excipient is selected from a filler, a glidant and a lubricant.
The process according to any one of claims 15-17, wherein the aqueous granulating liquid contains a binder.
The process according to claim 18, wherein the tablet or the tablet core consists of a mixture consisting of granules made from pirfenidone, a first disintegrant, a sugar alcohol, a binder and optionally a first filler, a second disintegrant, a second filler, a glidant and a lubricant, comprising the steps:
i) preparing a mixture consisting of pirfenidone, a first disintegrant, a sugar
alcohol and optionally a first filler, ii) subjecting the mixture obtained in step (i) to wet granulation using an
aqueous binder-containing solution as granulating liquid,

iii) mixing the granules obtained in step (ii) with a second disintegrant, a
second filler, a glidant and a lubricant, iv) subjecting the mixture obtained in step (iii) to compression to obtain the
tablet.
The process according to claim 19, wherein the first and second disintegrant is croscarmellose sodium, the sugar alcohol is mannitol, the optionally contained first filler and the second filler are microcrystalline cellulose, the glidant is silicon dioxide and the lubricant is sodium stearyl fumarate.