WO2016003091A1

WO2016003091A1 - Solid pharmaceutical composition comprising oseltamivir free base

Info

Publication number: WO2016003091A1
Application number: PCT/KR2015/006128
Authority: WO
Inventors: Seung Jun Lee; Jung Hyun Cho; Kyeong Soo Kim; Yong Il Kim; Jae Hyun Park; Jong Soo Woo
Original assignee: Hanmi Pharm. Co., Ltd.
Priority date: 2014-06-30
Filing date: 2015-06-17
Publication date: 2016-01-07
Also published as: KR20160002177A

Abstract

A solid pharmaceutical composition for oral administration including oseltamivir free base, for example, having a particle size d_(0.9)of about 200 ㎛ or less, a medicine including the same, and a method of preparing the solid pharmaceutical composition are provided. The solid pharmaceutical composition may be in the form of capsule, tablet, granules, dry syrup, chewable tablet, or powder.

Description

SOLID PHARMACEUTICAL COMPOSITION COMPRISING OSELTAMIVIR FREE BASE

The present disclosure relates to a pharmaceutical composition for oral administration including oseltamivir free base that may have a high initial dissolution rate with a reduced deviation, a medicine including the solid pharmaceutical composition, and a method of preparing the solid pharmaceutical composition.

Influenza A (H1N1) is usually called novel flu or novel influenza, and Tamiflu^TM(available from Roche) is used as a therapeutic agent therefor. Tamiflu^TM contains oseltamivir phosphate as an active ingredient that is known to have higher stability than oseltamivir free base and is available in the form of a suspension or capsule.

Novel flu is an acute respiratory disease (ARD) that can be accompanied by symptoms such as acute respiratory failure at early onset stage. Therefore, it is recommended by the United States Centers for Disease Control to start treatment with Tamiflu^TM within about 48 hours after symptom onset. Accordingly, an initial absorption rate of Tamiflu^TM after administration may significantly influence therapeutic effects. However, currently available Tamiflu^TM capsules including oseltamivir phosphate have a dissolution rate of merely about 57.8±20.9 % within 5 minutes under the gastric juice environment, even with a large deviation. Therefore, to achieve satisfactory therapeutic effects, there is a need to improve such a low initial dissolution rate and reduce a large deviation in dissolution rate.

To improve the initial dissolution rate, particle size of the active ingredient, one of the various factors to be considered, may be controlled. That is, it may be considered to reduce the particle size of oseltamivir phosphate as an active ingredient to increase a surface area of the oseltamivir phosphate, thereby consequently increasing the initial dissolution rate. However, it was found that reaching a desirable high initial dissolution rate (for example about 85% or greater) is difficult, even with the use of oseltamivir phosphate having a significantly small particle size obtained using a common grinder or mill (refer to examples in this specification). It was also found that when the particle size of oseltamivir phosphate is reduced to about 250 ㎛ to about 5 ㎛ of an average particle size d_(0.9)for the bottom 90%, solubility of the oseltamivir phosphate in the gastric juice environment at pH 1.2 varied over a wide range (for example, from about 0.654 g/ml to about 1.627 g/ml) (refer to examples in this specification). Accordingly, when a formulation including oseltamivir phosphate is prepared in the production field via grinding oseltamivir phosphate with a common grinder or mill, the dissolution rate, and in particular, initial dissolution rate of the formulation may have a large deviation, which may make quality control difficult.

As a result of much research into various aspects of improving an initial dissolution rate of a solid formulation, for example, a solid formulation such as capsules including oseltamivir phosphate, the inventors of the present application found that oseltamivir free base may have a remarkably high solubility compared to oseltamivir phosphate, that a desired high initial dissolution rate of oseltamivir free base may be achieved by reducing the particle size of the oseltamivir free base to a particular particle size range, and that deviation in dissolution rate of the oseltamivir free base may be reduced within the particular particle size range due to a reduced change in solubility within the particular particle range, which may make quality control in the production field easy. Therefore, the present disclosure provides a solid formulation including oseltamivir free base in a particular range of particle sizes.

According to an aspect of the present invention, there is provided a solid pharmaceutical composition for oral administration including oseltamivir free base.

In some embodiments, the oseltamivir free base may have an average particle size d_(0.9)of about 200 ㎛ or less, and in some embodiments, about 10 ㎛ to about 200 ㎛, the average particle size d_(0.9) for the bottom 90%.

In some embodiments, the solid pharmaceutical composition may be in the form of a capsule, a tablet, a dry syrup, powder, or a chewable tablet. In some embodiments, the solid pharmaceutical composition may be in the form of a dry syrup including granules of the oseltamivir free base obtained through granulation and a pharmaceutically acceptable additive. In some other embodiments, the solid pharmaceutical composition may be in the form of a capsule obtained by being filled with granules of the oseltamivir free base obtained through granulation and a pharmaceutically acceptable additive. In some other embodiments, the solid pharmaceutical composition may be in the form of a tablet obtained by tableting granules of the oseltamivir free base obtained through granulation together with a pharmaceutically acceptable additive.

In some embodiments, the solid pharmaceutical composition may further include at least one disintegrant selected from the group consisting of croscarmellose sodium, crospovidone, sodium starch glycolate, and low-substituted hydroxypropyl cellulose. In some embodiments, the solid pharmaceutical composition may further include at least one lubricant selected from the group consisting of magnesium stearate, talc, and sodium stearyl fumarate. In some embodiments, the solid pharmaceutical composition in the form of a capsule or a tablet may have a dissolution rate of about 85% or greater in about 5 minutes, as measured in an about 0.1N aqueous hydrochloric acid (HCl) solution at a paddle rotation speed of about 50 rpm according to Dissolution method II in the Korean Pharmacopoeia.

According to another aspect of the present invention, there is provided a medicine including any one of the solid pharmaceutical compositions according to the above-described embodiments, packed with a packing material having a water vapour transmission rate (WVTR) of about 4.0 g/m²/d or less. For example, the packing material having a WVTR of about 4.0 g/m²/d or less may be at least one selected from the group consisting of high-density polyethylene (HDPE), polyvinyl chloride-aluminum (PVC-Alu) blister, polyvinylidene chloride-aluminum (PVDC-Alu) blister, polychlorotrifluoroethylene-aluminum (PCTFE-Alu) blister, cyclic olefin copolymer-aluminum (COC-Alu) blister, and aluminum-aluminum (Alu-Alu) blister. In some embodiments, the medicine may have a total related compound content of about 2.0% or less when exposed under accelerated conditions of a temperature of about 40℃ and a relative humidity of about 75% for about 6 months.

According to another aspect of the present invention, a method of preparing a solid pharmaceutical composition includes: (a) performing wet granulation on a mixture of oseltamivir free base and a disintegrant by adding a binder solution to obtain wet granules; (b) drying the wet granules of step (a) to obtain granules; and (c) filling a capsule with the granules of step (b) and a pharmaceutically acceptable additive, or tableting the granules of step (b) together with a pharmaceutically acceptable additive.

According to another aspect of the present invention, a method of preparing a solid pharmaceutical includes: (a') performing dry granulation on a mixture of oseltamivir free base and a disintegrant with a roller compactor to obtain granules; and (b') filling a capsule with the granules of step (a') and a pharmaceutically acceptable additive, or tableting the granules of step (a') together with a pharmaceutically acceptable additive.

According to the one or more embodiments of the present disclosure, it was found that oseltamivir free base may have a remarkably high solubility compared to oseltamivir phosphate. When the oseltamivir free base has an average particle size d_(0.9) for the bottom 90% of about 200 ㎛ or less, for example, an average particle size d_(0.9) for the bottom 90% of about 10 ㎛ to about 200 ㎛, a solid pharmaceutical composition including the oseltamivir free base may have a dissolution rate of about 85% or greater in about 5 minutes. In particular, when the particle size of the oseltamivir free base is within these ranges, a deviation in dissolution rate may be reduced due to a reduced change in solubility. This may make quality control in the production field easy. Therefore, a solid pharmaceutical composition including the oseltamivir free base may have a high initial dissolution rate with a reduced deviation. Accordingly, drawbacks of conventional oseltamivir phosphate-containing solid formulation may be effectively solved.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although exemplary methods or materials are listed herein, other similar or equivalent ones are also within the scope of the present invention. All publications disclosed as references herein are incorporated in their entirety by reference.

According to an aspect of the present disclosure, a solid pharmaceutical composition for oral administration includes oseltamivir free base. The oseltamivir free base may have an average particle size d_(0.9)for the bottom 90% of about 200 ㎛ or less.

As used herein, the expression average particle size d_(0.9)for the bottom 90% refers to an average particle size of particles that fall into 90% of the total number of particles counted from the smallest particle by using a particle size analyzer. This term is also referred to simply as "particle size d_(0.9)".

The inventors of the present application found that when the particle size of the oseltamivir free base is reduced within a specific range, for example, to have a particle diameter d_(0.9)of about 200 ㎛ or less, the solubility of the oseltamivir free base may be remarkably increased with a reduced deviation in solubility. In other words, the inventors of the present application found that when the particle size of the oseltamivir free base is reduced to have a particle diameter d_(0.9) of about 200 ㎛ to about 5 ㎛, the solubility of the oseltamivir free base, for example, in the stomach environment at pH 1.2 may be improved to about 2.429 ~ 2.571 g/ml with a reduced deviation in solubility. On the other hand, it was also found that when the particle size of oseltamivir phosphate is reduced to a particle size d_(0.9) of about 200 ㎛ to about 5 ㎛, which is the same level as above, the solubility of the oseltamivir phosphate, for example, in the stomach environment at pH 1.2 may be increased merely to about 0.885 ~ 1.627 g/ml even with a large deviation in solubility. Such effects are unexpectable in the art, in which compounds in free base form are conventionally known to have low solubility, poor physical characteristics not suitable for drug formulation, and low initial dissolution rate, compared to compounds in salt known to be appropriate for a medicine.

In some embodiments of the solid pharmaceutical composition, the oseltamivir free base may have a particle size d_(0.9) of about10 ㎛ to about 200 ㎛. When the oseltamivir free base has a particle size d_(0.9) of less than 10 ㎛ (for example, about 5 ㎛), granules of the oseltamivir free base may have poor flowability and not be filled into a capsule or made into tablets. When the oseltamivir free base has a particle size d_(0.9) exceeding 200 ㎛, a desirable initial dissolution rate may not be attained.

In some embodiments, the solid pharmaceutical composition may be in the form of a capsule, a tablet, a dry syrup, granules, powder, or a chewable tablet.

In some embodiments, the solid pharmaceutical composition may be in the form of a dry syrup that includes granules of the oseltamivir free base obtained through granulation and a pharmaceutically acceptable additive (for example, talc, xanthan gum, D-solbitol, saccharin, anhydrous citric acid, and the like). In some other embodiments, the solid pharmaceutical composition may be in the form of a capsule obtained by being filled with granules of the oseltamivir free base obtained through granulation and a pharmaceutically acceptable additive. In some other embodiments, the solid pharmaceutical composition may be in the form of a tablet obtained by tableting granules of the oseltamivir free base obtained through granulation together with a pharmaceutically acceptable additive.

In some embodiments, the granulation of the oseltamivir free base may be performed by wet granulation or dry granulation. For example, wet granulation may be performed using a binder solution that is obtained by dissolving a binder such as povidone, hydroxypropyl cellulose, or hypromellose in an appropriate solvent such as 70% ethanol, according to a common wet granulation method. For example, dry granulation may be performed using a common apparatus such as a roll compactor. In some embodiments, the granulation of the oseltamivir free base may be wet granulation.

Oseltamivir free base tends to have lower stability in a combination with a common pharmaceutically available additive. In this regard, the inventors of the present application found that this limitation may be overcome with a specific disintegrant. In particular, it was found that stability of oseltamivir free base in formulation may be ensured by granulating the oseltamivir free base with a specific disintegrant. The specific disintegrant may be at least one selected from the group consisting of croscarmellose sodium, crospovidone, sodium starch glycolate, and low-substituted hydroxypropyl cellulose. The amount of the disintegrant may be in about 1wt% to about 20wt% based on a total weight of the solid pharmaceutical composition. When the amount of the disintegrant is within this range, disintegration of a capsule or a tablet of the solid pharmaceutical composition may be facilitated when the capsule or tablet is wet, and an adhering problem during tableting may be suppressed. In addition, the density of the granules may be suitable for tableting or capsule filling, and shape change of the formulated tablets or capsules caused by moisture may also be prevented. When the amount of the disintegrant is less than about 1wt%, the dissolution of the oseltamivir free base may become slow. When the amount of the disintegrant exceeds about 20% by weight, the stability of the oseltamivir free base may be reduced.

In some embodiments, in the solid pharmaceutical composition in the form of a capsule or tablet, the pharmaceutically acceptable additive may include various at least one or more lubricants. It is known that the stability of a formulation may be reduced and sufficient content uniformity may not be obtained depending on a type of lubricant. The inventors of the present application found that these limitations may be overcome with a specific lubricant. For example, the specific lubricant may be at least one selected from magnesium stearate, talc, and sodium stearyl fumarate. The pharmaceutically acceptable additive may further include at least one disintegrant selected from, for example, the group consisting of croscarmellose sodium, crospovidone, sodium starch glycolate, and low-substituted hydroxypropyl cellulose, if required. The amount of the lubricant may be in a range of about 0.25 wt% to about 10 wt% based on the total weight of the solid pharmaceutical composition. When the amount of the lubricant is within this range, for example, tablets of the solid pharmaceutical composition may be easily discharged from a compression die, and an adhering problem and breaking of tablets or tablet layer separation during tableting may be also be escaped. Lubricants are known to have water-repellency. Accordingly, when an excess of the lubricant is used, unexpected problems such as disintegration delay, dissolution reduction, or the like may occur. That is, when the amount of the lubricant is less than about 0.25 wt%, reduced productivity may occur due to the reduced efficiency of tableting or capsule filling process, and when the amount of the lubricant is more than about 10 wt%, reduced dissolution, delayed disintegration, and reduced stability may occur.

In some embodiments, there is provided the solid pharmaceutical composition in the form of a capsule having a dissolution rate of about 85% or greater in about 5 minutes, as measured in an about 0.1N aqueous hydrochloric acid (HCl) solution at a paddle rotation speed of about 50 rpm according to Dissolution method II in the Korean Pharmacopoeia.

In some other embodiments, there is provided the solid pharmaceutical composition in the form of a tablet having a dissolution rate of about 85% or greater in about 5 minutes, as measured in an about 0.1N aqueous HCl solution at a paddle rotation speed of about 50 rpm according to Dissolution method II in the Korean Pharmacopoeia.

According to another aspect of the present disclosure, there is provided a medicine obtained by packing the above-described solid pharmaceutical composition with a packing material having a water vapour transmission rate (WVTR) of about 4.0 g/m²/d or less. As used here, the term water vapour transmission rate (WVTR) refers to a transmission rate of water vapour measured under the conditions of about 38℃ and about 90% of relative humidity.

The packing material having a WVTR of about 4.0 g/m²/d or less may be at least one selected from the group consisting of high-density polyethylene (HDPE), polyvinyl chloride-aluminum (PVC-Alu) blister, polyvinylidene chloride-aluminum (PVDC-Alu) blister, polychlorotrifluoroethylene-aluminum blister (PCTFE-Alu) blister, cyclic olefin copolymer-aluminum (COC-Alu) blister, and aluminum-aluminum (Alu-Alu) blister. In some embodiments, the medicine may have a total related compound content of about 2.0% or less when exposed under accelerated conditions of a temperature of about 40℃ and a relative humidity of about 75% for about 6 months. The related compounds may be analyzed according to a related compound analysis method described in Oseltamivir phosphate Capsule section of the U.S. Pharmacopeia (USP).

According to another aspect of the present disclosure, there are provided methods of preparing the above-described solid pharmaceutical compositions .

In some embodiments, a method of preparing a solid pharmaceutical composition for oral administration including oseltamivir free base may include: (a) performing wet granulation on a mixture of oseltamivir free base and a disintegrant by adding a binder solution to obtain wet granules; (b) drying the wet granules of step (a) to obtain granules; and (c) filling a capsule with the granules of step (b) and a pharmaceutically acceptable additive, or tableting the granules of step (b) together with a pharmaceutically acceptable additive. The disintegrant and binder solution used in step (a) may be the same as those described above. The wet granulation of step (a) may be performed according to a common method used in the field of pharmaceutics. The drying of step (b) may also be performed according to a common method used in the field of pharmaceutics, and may further include sieving the obtained granules, if required. The pharmaceutically acceptable additive used in step (c) may also be the same as that described above.

In some other embodiments, the method of preparing a solid pharmaceutical composition for oral administration including oseltamivir free base may include: (a') performing dry granulation on a mixture of oseltamivir free base and a disintegrant with a roll compactor to obtain granules; and (b') filling a capsule with the granules of step (a') and a pharmaceutically acceptable additive, or tableting the granules of step (a') together with a pharmaceutically acceptable additive. The disintegrant used in step (a') and the pharmaceutically acceptable additive used in step (b') may be the same as those described above. The dry granulation of step (a') may be performed according to a common method used in the field of pharmaceutics, and may further include sieving the granules obtained in step (a'), if required.

MODE OF THE INVENTION

One or more embodiments of the present disclosure will now be described in detail with reference to the following examples. However, these examples are only for illustrative purposes and are not intended to limit the scope of the one or more embodiments of the present disclosure.

Example 1: Saturation solubility test on different particle sizes

A solubility test on oseltamivir free base and oseltamivir phosphate each having different particle sizes as shown in Table 1 was performed with various test solutions. Test samples of different particle sizes were prepared by grinding source materials having a particle size of about 300 ㎛, which were supplied by a manufacturer and used as samples having the largest particle size, using a grinder Air Jet Mill under conditions enabling to obtain target particle sizes. According to the solubility test, about 5 g of a test sample was added to about 1 mL of each test solution, saturated, and stirred at room temperature for about 2 hours , followed by centrifugation to obtain a supernatant, which was then analyzed by high-performance liquid chromatography (HPLC).

[Table 1]

Based on the results in Table 1, it was found that the solubility of oseltamivir free base rapidly increased according to reduced particle sizes, compared to oseltamivir phosphate, and in particular, there was nearly no difference in solubility between the formulations of different particle sizes in a particle size d_(0.9) range of about 5 ㎛ to about 200 ㎛ in all of the test solutions. On the other hand, the solubility of oseltamivir phosphate was lower in all of the test solutions than oseltamivir free base, with a large variation in solubility over the full range of particles sizes, which may cause quality control problems.

Example 2: Preparation of granules and evaluation of capsules and tablets obtained from the granules

Capsules and tablets were prepared as follows according to the compositions in Table 2, in which used ingredients and amounts thereof are shown.

Povidone was dissolved in an about 70% ethanol solution to obtain a binder solution. After oseltamivir free base or oseltamivir phosphate, pregelatinized starch, and croscarmellose sodium (about 70% of the amount shown in Table 2) were added into a chamber of a high-speed mixer and mixed for about 3 minutes to obtain a mixture, the binder solution was added to the mixture at an agitator speed of about 100 rpm and a chopper speed of about 3000 rpm for about 2 minutes to wet-granulate the ingredients. The resulting wet granules were then dried in a fluid bed dryer for about 15 minutes, thereby preparing granules.

The resultant granules in an equivalent amount to about 75 mg of oseltamivir was taken and mixed with talc, sodium stearyl fumarate, and croscarmellose sodium (about 30% of the amount of each ingredient in Table 2) to obtain a mixture, which was then filled into gelatin capsules (No. 2, available from Seoheung Capsule, Korea), thereby preparing each formulation as capsules. The resultant granules in an equivalent amount to about 75 mg of oseltamivir was taken and mixed with talc, sodium stearyl fumarate, and croscarmellose sodium (about 30% of the amount of each ingredient in Table 2) to obtain a mixture, which was then tableted under the condition of a hardness of about 10 kp in a rotary tablet press (MRC-18, available from Sejong Pharmatech Co., Ltd., Korea) to form tablets.

[Table 2]

A dissolution test was performed on the resulting capsules and tablets under the conditions as follows. The results are shown in Table 3.

< Dissolution test conditions >

Dissolution test method: Dissolution method II in the Korean Pharmacopoeia (Paddle method)

Dissolution medium: about 0.1N-HCl solution

Amount of dissolution medium: about 900 mL

Temperature of dissolution medium: about 37.5 ℃

Paddle speed: about 50 rpm

Number of test samples in each experimental group: 6

Sampling time: about 5 min

[Table 3]

Based on the results in Table 3, it was found that in the formulations using oseltamivir free base had a remarkably improved dissolution rate of about 85% or greater in about 5 minutes in a particle size d_(0.9) range of about 200 ㎛ or less (i.e., Formulations 1 to 5), with nearly no difference in solubility depending on particle size. However, only in the case of Formulation 1, the granules were found to have poor granule flowability, even though having a good dissolution rate, and thus the granules are unsuitable for capsule filling or tableting, which may interrupt mass-scale production. Accordingly, an appropriate particle size d_(0.9) of the oseltamivir free base may be in a range of about 10 ㎛ to about 200 ㎛. Formulations 7 to 12 using oseltamivir phosphate had a remarkably low dissolution rate in about 5 minutes, with a large variation in dissolution rate depending on particle size, which may interrupt production of uniform-quality products. These results were in the same tendency both in capsule and tablet forms.

Example 3: Stability test with different disintegrants

A stability test was performed on mixtures of oseltamivir free base or oseltamivir phosphate that were prepared by mixing with different disintegrants and adding an appropriate amount of purified water to the resultant mixture as shown in Table 4. After each mixture was exposed under accelerated conditions of a temperature of about 50℃ and a relative humidity of about 75% for about 2 weeks, related compounds were analyzed according to a related compound analysis method described in Oseltamivir phosphate Capsule section of the U.S. Pharmacopeia (USP), and a total related compound content was calculated therefrom. The results are shown in Table 4.

[Table 4]

In general, compounds in free base are conventionally known to have lower stability than compounds in salt. However, based on the results of Table 4, it was found that oseltamivir free base was found to have a similar solubility level to oseltamivir phosphate when used together with croscarmellose sodium, crospovidone, sodium starch glycolate, or low-substituted hydroxypropyl cellulose as a disintegrant.

Example 4: Stability test with different lubricants

A stability test was performed on mixtures of oseltamivir free base or oseltamivir phosphate that were prepared by mixing with different lubricants and adding an appropriate amount of purified water to the resultant mixture as shown in Table 5. After each mixture was exposed under accelerated conditions of a temperature of about 50℃ and a relative humidity of about 75% for about 2 weeks, related compounds were analyzed according to a related compound analysis method described in Oseltamivir phosphate Capsule section of the USP, and a total related compound content was calculated therefrom. The results are shown in Table 5.

[Table 5]

Based on the results of Table 5, it was found that oseltamivir free base was found to have a similar solubility level to oseltamivir phosphate when used together with magnesium stearate, talc, and/or sodium stearyl fumarate as a lubricant.

Example 5: Stability test with different packing materials

A stability test was performed on each of capsules and tablets prepared in Example 2, and a dry syrup which was prepared by taking granules obtained in Example 2 in an equivalent amount to about 600 mg of oseltamivir and then mixing with talc (about 10 mg), xanthan gum (about 5 mg), D-solbitol (about 30 mg), saccharin (about 10 mg), and anhydrous citric acid (about 10 mg). After capsule or tablet prepared in Example 2 and the dry syrup were each taken in an equivalent amount to about 600 mg of oseltamivir, and then packed with different packing materials as shown in Table 6, a stability test was performed. After the formulations packed with different packing materials were exposed under accelerated conditions of a temperature of about 40℃ and a relative humidity of about 75% for about 6 months, related compounds were analyzed according to a related compound analysis method described in Oseltamivir phosphate Capsule section of the USP, and a total related compound content was calculated therefrom. The results are shown in Table 6.

[Table 6]

Based on the results in Table 6, it was found that capsules, tablets, and dry syrup including oseltamivir free base were found to have poor stability when packed with packing materials having a water vapour transmission rate (WVTR) exceeding about 4.0 g/m²/d. On the other hand, the formulations including oseltamivir free base that were packed with a packing material having a WVTR of 4.0 or less were found to have a total related compound content of about 2% or less, indicating good stability of oseltamivir.

It should be understood that the exemplary embodiments described therein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments of the present invention have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.

Claims

A solid pharmaceutical composition for oral administration comprising oseltamivir free base.
The solid pharmaceutical composition of claim 1, wherein the oseltamivir free base has an average particle size d_(0.9)for the bottom 90% of about 200 ㎛ or less.
The solid pharmaceutical composition of claim 2, wherein the oseltamivir free base has an average particle size d_(0.9) for the bottom 90% of about 10 ㎛ to about 200㎛.
The solid pharmaceutical composition of claim 1, wherein the solid pharmaceutical composition is in the form of a capsule, a tablet, granules, a dry syrup, powder, or a chewable tablet.
The solid pharmaceutical composition of claim 1, wherein the solid pharmaceutical composition is in the form of a dry syrup comprising granules of the oseltamivir free base obtained through granulation and a pharmaceutically acceptable additive.
The solid pharmaceutical composition of claim 1, wherein the solid pharmaceutical composition is in the form of a capsule obtained by being filled with granules of the oseltamivir free base obtained through granulation and a pharmaceutically acceptable additive.
The solid pharmaceutical composition of claim 1, wherein the solid pharmaceutical composition is in the form of a tablet obtained by tableting granules of the oseltamivir free base obtained through granulation together with a pharmaceutically acceptable additive.
The solid pharmaceutical composition of claim 1, wherein the solid pharmaceutical composition further comprises at least one disintegrant selected from the group consisting of croscarmellose sodium, crospovidone, sodium starch glycolate, and low-substituted hydroxypropyl cellulose.
The solid pharmaceutical composition of claim 1, wherein the solid pharmaceutical composition further comprises at least one lubricant selected from the group consisting of magnesium stearate, talc, and sodium stearyl fumarate.
The solid pharmaceutical composition of claim 1, wherein the solid pharmaceutical composition has a dissolution rate of about 85% or greater in about 5 minutes, as measured in an about 0.1N aqueous hydrochloric acid (HCl) solution at a paddle rotation speed of about 50 rpm according to Dissolution method II in the Korean Pharmacopoeia.
A medicine comprising the solid pharmaceutical composition of any one of claims 1 to 10, packed with a packing material having a water vapour transmission rate (WVTR) of about 4.0 g/m²/d or less.
The medicine of claim 11, wherein the packing material having a WVTR of about 4.0 g/m²/d or less is at least one selected from the group consisting of high-density polyethylene (HDPE), polyvinyl chloride-aluminum (PVC-Alu) blister, polyvinylidene chloride-aluminum (PVDC-Alu) blister, polychlorotrifluoroethylene-aluminum (PCTFE-Alu) blister, cyclic olefin copolymer-aluminum (COC-Alu) blister, and aluminum-aluminum (Alu-Alu) blister.
The medicine of claim 11, wherein the medicine has a total related compound content of about 2.0% or less when exposed under accelerated conditions of a temperature of about 40℃ and a relative humidity of about 75% for about 6 months.
A method of preparing a solid pharmaceutical composition for oral administration comprising oseltamivir free base, the method comprising:

(a) performing wet granulation on a mixture of oseltamivir free base and a disintegrant by adding a binder solution to obtain wet granules;

(b) drying the wet granules of step (a) to obtain granules; and

(c) filling a capsule with the granules of step (b) and a pharmaceutically acceptable additive, or tableting the granules of step (b) together with a pharmaceutically acceptable additive.
A method of preparing a solid pharmaceutical composition for oral administration comprising oseltamivir free base, the method comprising:

(a') performing dry granulation on a mixture of oseltamivir free base and a disintegrant with a roller compactor to obtain granules; and

(b') filling a capsule with the granules of step (a') and a pharmaceutically acceptable additive, or tableting the granules of step (a') together with a pharmaceutically acceptable additive.