the term “ single drug formulation ” as used herein means an embodiment of a formulation containing a drug . the term “ single formulation ” as used herein is also referred to as “ combined formulation ”, and means an embodiment of a formulation containing two or more drugs in the formulation . the term “ single formulation ” includes a formulation containing subformulations functionally different in releasing properties , such as the modified release portion and the immediate release portion in the present invention . as an embodiment of the “ single formulation ”, multi - layered tablets , such as a bi - layered tablet in which the modified release portion and the immediate release portion are laminated , a multi - layered tablet in which a plurality of the modified release portion ( s ) and the immediate release portion ( s ) are laminated , and a three - layered tablet in which a drug - free layer is sandwiched between the modified release portion and the immediate release portion ; a dry - coated tablet having the modified release portion as an internal core and the immediate release portion as an outer layer ; and a film - coated tablet in which the modified release portion as a core is coated with the immediate release portion by film coating , may be exemplified . as another embodiment , a bi - layered tablet may be exemplified . the term “ modified release portion ” as used herein means a portion which is contained in the single formulation , and which controls the release of the drug . the term “ immediate release portion ” as used herein means a portion which is contained in the single formulation , and which rapidly releases the drug from the pharmaceutical composition ( in the case of a “ soluble ” drug , “ release ” has almost the same meaning as “ dissolution ”). the term “ rapidly release ( dissolve )” or “ rapid release ( dissolution )” means that the release of the drug is not controlled . more particularly , it is defined by the dissolution rate of solifenacin , as described below , and it means , for example , that when a dissolution test is carried out in accordance with the dissolution test , method 1 ( basket method , 100 rpm ) described in the japanese pharmacopoeia , 85 % or more of the drug is dissolved after 15 minutes . the term “ maximum percentage of dissolution ” as used herein means the percentage of dissolution when a dissolution rate of the drug from the pharmaceutical composition reaches a plateau in a dissolution test under predetermined conditions . the pharmaceutical composition for oral administration of the present invention will be explained hereinafter . mirabegron or a pharmaceutically acceptable salt thereof to be used in the present invention , is easily available by preparing it in accordance with , for example , the method described in patent literature 2 , or a modified method thereof . mirabegron may be used in a free form which is not a salt , and may form pharmaceutically acceptable salts with acids . examples of the salts include acid addition salts with mineral acids such as hydrochloric acid , hydrobromic acid , hydriodic acid , sulfuric acid , nitric acid , and phosphoric acid ; and acid addition salts with organic acids such as formic acid , acetic acid , propionic acid , oxalic acid , malonic acid , succinic acid , fumaric acid , maleic acid , lactic acid , malic acid , citric acid , tartaric acid , carbonic acid , picric acid , methanesulfonic acid , ethanesulfonic acid , and glutamic acid . these salts can be prepared by a conventional method . the dose of mirabegron in the single formulation ( combined formulation ) may be appropriately determined in accordance with the symptoms , the age and the sex of a patient to be treated , and the like . when mirabegron is orally administered to an adult , the daily dose is 0 . 01 mg / kg to 100 mg / kg , and is administered once or divided into two to four doses per day . the content of mirabegron per modified release portion is , for example , 1 % by weight to 70 % by weight , 5 % by weight to 70 % by weight as another embodiment , and 5 % by weight to 50 % by weight as still another embodiment . the content of mirabegron per formulation is 1 mg to 500 mg , and 10 mg to 200 mg as another embodiment . solifenacin or a pharmaceutically acceptable salt thereof to be used in the present invention , is easily available by preparing it in accordance with the method described in patent literature 5 , or a modified method thereof . solifenacin may be used in a free form which is not a salt , and may form pharmaceutically acceptable salts with acids . examples of the salts include acid addition salts with mineral acids such as hydrochloric acid , hydrobromic acid , hydriodic acid , sulfuric acid , nitric acid , and phosphoric acid ; and acid addition salts with organic acids such as formic acid , acetic acid , propionic acid , oxalic acid , malonic acid , succinic acid , fumaric acid , maleic acid , lactic acid , malic acid , citric acid , tartaric acid , carbonic acid , picric acid , methanesulfonic acid , ethanesulfonic acid , and glutamic acid . solifenacin succinate may be exemplified in another embodiment . these salts can be prepared by a conventional method . the dose of solifenacin in the single formulation ( combined formulation ) may be appropriately determined for each patient in accordance with , for example , the route of administration , symptoms of a disease , the age and the sex of a patient to be treated , and the like . when solifenacin succinate is orally administered to an adult , the daily dose is approximately 0 . 01 mg / kg to 100 mg / kg , and is administered once or divided into two to four doses per day . the content of solifenacin is not particularly limited , so long as it is an effective amount for treatment or prevention . the content of solifenacin with respect to the immediate release portion is , for example , 0 . 5 % by weight to 85 % by weight , 0 . 5 % by weight to 80 % by weight as another embodiment , 0 . 5 % by weight to 50 % by weight as still another embodiment , and 0 . 5 % by weight to 10 % by weight as still another embodiment . the content of solifenacin per formulation is 0 . 01 mg to 100 mg as an embodiment , 0 . 5 mg to 50 mg as another embodiment , 0 . 5 mg to 20 mg as still another embodiment , and 0 . 5 mg to 10 mg as still another embodiment . the “ modified release portion ” in the present invention is a formulation in which the drug release rate after 30 minutes from the beginning of a dissolution test is less than 85 %, and is a formulation capable of controlling the release of a drug to the extent that the effects of food intake are decreased . the dissolution test may be carried out , for example , in accordance with the dissolution test ( paddle method ) described in the united states pharmacopeia , using 900 ml of an appropriate test fluid ( for example , a usp phosphate buffer ( ph 6 . 8 )), at a paddle rotation speed of 100 rpm , or in accordance with the dissolution test , method 2 described in the japanese pharmacopoeia , using 900 ml of an appropriate test fluid ( for example , a mc . ilvain buffer ( ph 6 . 8 )), at a paddle rotation speed of 50 rpm to 200 rpm . more particularly , it is a formulation prepared by combining a hydrogel - forming polymer with an additive which allows water to penetrate into the formulation ( hydrophilic base ). the hydrogel - forming polymer to be used in the present invention , is not particularly limited , so long as it can control the drug releasing rate , to the extent that the blood concentration profile of the drug is not affected by the presence or absence of food intake . the molecular weight of the hydrogel - forming polymer is , for example , 100 , 000 or more , 100 , 000 to 8 , 000 , 000 in another embodiment , 100 , 000 to 5 , 000 , 000 in still another embodiment , and 100 , 000 to 2 , 000 , 000 in still another embodiment . the viscosity of the hydrogel - forming polymer is , for example , 12 mpa · s or more in a 5 % aqueous solution at 25 ° c . ; 12 mpa · s or more in a 5 % aqueous solution at 25 ° c ., and 40 , 000 mpa · s or less in a 1 % aqueous solution at 25 ° c . in another embodiment ; 400 mpa · s or more in a 2 % aqueous solution at 25 ° c ., and 7 , 500 mpa · s or less in a 1 % aqueous solution at 25 ° c . in still another embodiment ; and 400 mpa · s or more in a 2 % aqueous solution at 25 ° c ., and 5 , 500 mpa · s or less in a 1 % aqueous solution at 25 ° c . in still another embodiment . examples of the hydrogel - forming polymer to be used in the present invention , include polyethylene oxide , hypromellose , hydroxypropylcellulose , methylcellulose , carboxymethylcellulose sodium , hydroxyethylcellulose , and carboxyvinyl polymers . examples of the hydrogel - forming polymer in another embodiment include polyethylene oxide , hypromellose , and hydroxypropylcellulose . examples of the hydrogel - forming polymer in still another embodiment include polyethylene oxide . examples of polyethylene oxide ( hereinafter sometimes referred to as peo ) include product names , polyox wsr - 308 [ average molecular weight : 8 , 000 , 000 , viscosity : 10 , 000 - 15 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )], polyox wsr - 303 [ average molecular weight : 7 , 000 , 000 , viscosity : 7 , 500 - 10 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )], polyox wsr coagulant [ average molecular weight : 5 , 000 , 000 , viscosity : 5 , 500 - 7 , 500 mpa · s ( 1 % aqueous solution at 25 ° c . )], polyox wsr - 301 [ average molecular weight : 4 , 000 , 000 , viscosity : 1 , 650 - 5 , 500 mpa · s ( 1 % aqueous solution at 25 ° c . )], polyox wsr - n - 60k [ average molecular weight : 2 , 000 , 000 , viscosity : 2 , 000 - 4 , 000 mpa · s ( 2 % aqueous solution at 25 ° c . )], polyox wsr - n - 12k [ average molecular weight : 1 , 000 , 000 , viscosity : 400 - 800 mpa · s ( 2 % aqueous solution at 25 ° c . )], polyox wsr - 1105 [ average molecular weight : 900 , 000 , viscosity : 8 , 800 - 17 , 600 mpa · s ( 5 % aqueous solution at 25 ° c . )], polyox wsr - 205 [ average molecular weight : 600 , 000 , viscosity : 4 , 500 - 8 , 800 mpa · s ( 5 % aqueous solution at 25 ° c . )], polyox wsr - n - 750 [ average molecular weight : 300 , 000 , viscosity : 600 - 1200 mpa · s ( 5 % aqueous solution at 25 ° c . )], polyox wsr - n - 80 [ average molecular weight : 200 , 000 , viscosity : 55 - 90 mpa · s ( 5 % aqueous solution at 25 ° c . )], and polyox wsr - n - 10 [ average molecular weight : 100 , 000 , viscosity : 12 - 50 mpa · s ( 5 % aqueous solution at 25 ° c . )]( manufactured by dow ). examples of hypromellose ( hereinafter sometimes referred to as hpmc ) include product name metolose 90sh50000 [ viscosity in a 2 % aqueous solution at 20 ° c . : 2 , 900 - 3 , 900 mpa · s ], metolose sb - 4 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 4 mpa · s ), tc - 5rw ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 6 mpa · s ), tc - 5s ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 15 mpa · s ), tc - 5r ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 6 mpa · s ), tc - 5m ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 4 . 5 mpa · s ), tc - 5e ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 3 mpa · s ), metolose 60sh - 50 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 50 mpa · s ), metolose 65sh - 50 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 50 mpa · s ), metolose 90sh - 100 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 100 mpa · s ), metolose 90sh - 100sr ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 100 mpa · s ), metolose 65sh - 400 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 400 mpa · s ), metolose 90sh - 400 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 400 mpa · s ), metolose 65sh - 1500 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 1 , 500 mpa · s ), metolose 60sh - 4000 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 4 , 000 mpa · s ), metolose 65sh - 4000 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 4 , 000 mpa · s ), metolose 90sh - 4000 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 4 , 000 mpa · s ), metolose 90sh - 4000sr ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 4 , 000 mpa · s ), metolose 90sh - 15000 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 15 , 000 mpa · s ), metolose 90sh - 15000sr ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 15 , 000 mpa · s ), and metolose 90sh - 30000 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 30 , 000 mpa · s ). examples of hydroxypropylcellulose ( hereinafter sometimes referred to as hpc ) include hpc - ssl ( product name , nippon soda co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : 2 . 0 - 2 . 9 mpa · s ), hpc - sl ( product name , nippon soda co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : 3 . 0 - 5 . 9 mpa · s ), hpc - l ( product name , nippon soda co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : 6 . 0 - 10 . 0 mpa · s ), hpc - m ( product name , nippon soda co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : 150 - 400 mpa · s ), and hpc - h ( product name , nippon soda co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : 1 , 000 - 4 , 000 mpa · s ). examples of methylcellulose ( hereinafter sometimes referred to as mc ) include metolose sm15 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 15 mpa · s ), metolose sm25 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 25 mpa · s ), metolose sm100 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 100 mpa · s ), metolose sm400 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 400 mpa · s ), metolose sm1500 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 1 , 500 mpa · s ), and metolose sm4000 ( product name , shin - etsu chemical co ., ltd . )( viscosity in a 2 % aqueous solution at 20 ° c . : approximately 4 , 000 mpa · s ). examples of carboxymethylcellulose sodium ( hereinafter sometimes referred to as cmcna ) include product names , sunrose f - 30mc [ viscosity : 250 - 350 mpa · s ( 1 % aqueous solution at 25 ° c . )], sunrose f - 150mc [ average molecular weight : 200 , 000 , viscosity : 1 , 200 - 1 , 800 mpa · s ( 1 % aqueous solution at 25 ° c . )], sunrose f - 600mc [ viscosity : 6 , 000 - 8 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )], sunrose f - 1000mc [ average molecular weight : 420 , 000 , viscosity : 8 , 000 - 12 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )], sunrose f - 1400mc [ viscosity : 12 , 000 - 15 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )], and sunrose f - 300mc [ average molecular weight : 300 , 000 , viscosity : 2 , 500 - 3 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )]( manufactured by nippon paper chemicals co ., ltd .). examples of hydroxyethylcellulose ( hereinafter sometimes referred to as hec ) include product names , hec daicel se850 [ average molecular weight : 1 , 480 , 000 , viscosity : 2 , 400 - 3 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )], and hec daicel se900 [ average molecular weight : 1 , 560 , 000 , viscosity : 4 , 000 - 5 , 000 mpa · s ( 1 % aqueous solution at 25 ° c . )]( manufactured by daicel chemical industries , ltd .). examples of carboxyvinyl polymers include carbopol 940 ( average molecular weight : approximately 2 , 500 , 000 , manufactured by b . f . goodrich chemical ). these hydrogel - forming polymers may be used alone , or as an appropriate combination of two or more thereof . a combination of different lots may be used . the content of the hydrogel - forming polymer is not particularly limited , so long as it is an amount to the extent that the blood concentration profile of the drug is not affected by the presence or absence of food intake . the content of the hydrogel - forming polymer with respect to the modified release portion is , for example , 1 % by weight to 70 % by weight , 3 % by weight to 70 % by weight as another embodiment , 5 % by weight to 70 % by weight as still another embodiment , 10 % by weight to 60 % by weight as still another embodiment , and 10 % by weight to 40 % by weight as still another embodiment . the content of the hydrogel - forming polymer per formulation is 1 % by weight to 45 % by weight , 2 % by weight to 45 % by weight as another embodiment , 3 % by weight to 45 % by weight as still another embodiment , 5 % by weight to 35 % by weight as still another embodiment , and 5 % by weight to 25 % by weight as still another embodiment . the content of the hydrogel - forming gel with respect to the weight of the drug is 0 . 1 % by weight to 1000 % by weight , 1 % by weight to 500 % by weight as another embodiment , and 5 % by weight to 300 % by weight as still another embodiment . a polymer of which the viscosity ( before mixing ) is beyond the specific range can be used as an appropriate combination with one or more other polymers , in cases where the mixture obtained by mixing these plural polymers has a viscosity ( as measured before use ) within the specific range . in the additive which allows water to penetrate into the modified release portion ( hydrophilic base ) to be used in the present invention , the amount of water necessary to dissolve 1 g of the hydrophilic base at 20 ± 5 ° c . is 10 ml or less , 6 ml or less in another embodiment , 5 ml or less in still another embodiment , and 4 ml or less in still another embodiment . when the hydrophilic base has a higher solubility to water , the effect that allows water to penetrate into the formulation is higher . examples of the hydrophilic base include : water - soluble polymers , such as polyethylene glycol [ peg : for example , product names peg 400 , peg 1500 , peg 4000 , peg 6000 , and peg 20000 ( manufactured by nof corporation )], polyvinylpyrrolidone [ pvp : for example , product name pvp k30 ( manufactured by basf )], and the like ; sugar alcohols , such as d - mannitol , d - sorbitol , xylitol , and the like ; saccharides , such as lactose , sucrose , anhydrous maltose , d - fructose , dextran ( for example , dextran 40 ), glucose , and the like ; surfactants , such as polyoxyethylene hydrogenated castor oil [ hco : for example , cremophor rh40 ( manufactured by basf ), hco - 40 , hco - 60 ( manufactured by nikko chemicals )], polyoxyethylene polyoxypropylene glycol [ for example , pluronic f68 ( manufactured by asahi denka and the like )], polyoxyethylene sorbitan higher fatty acid esters [ tween : for example , tween 80 ( manufactured by kanto chemical )], and the like ; salts , such as sodium chloride , magnesium chloride , and the like ; organic acids , such as citric acid , tartaric acid , and the like ; amino acids , such as glycine , β - alanine , lysine hydrochloride , and the like ; and aminosaccharides , such as meglumine , and the like . as another embodiment , peg , pvp , d - mannitol , d - sorbitol , xylitol , lactose , sucrose , anhydrous maltose , d - fructose , dextran , glucose , polyoxyethylene polyoxypropylene glycol , sodium chloride , magnesium chloride , citric acid , tartaric acid , glycine , β - alanine , lysine hydrochloride , or meglumine may be exemplified . as still another embodiment , peg , pvp , d - mannitol , lactose , sucrose , sodium chloride , or polyoxyethylene polyoxypropylene glycol may be exemplified . as still another embodiment , peg may be exemplified . these hydrophilic bases may be used alone , or as an appropriate combination of two or more thereof . the content of the hydrophilic base is not particularly limited , so long as it is an amount capable of controlling the release of the drug to the extent that the release of the drug is not affected by food . the content of the hydrophilic base with respect to the modified release portion is , for example , 5 % by weight to 75 % by weight , 5 % by weight to 70 % by weight in another embodiment , and 20 % by weight to 60 % by weight in still another embodiment . the content of the hydrophilic base per formulation is 3 % by weight to 44 % by weight as an embodiment , 3 % by weight to 40 % by weight as another embodiment , and 12 % by weight to 35 % by weight as still another embodiment . an antioxidant may be contained in the modified release portion in the present invention . the antioxidant is not particularly limited , so long as the influence of dissolution behavior can be avoided . examples of the antioxidant include butylated hydroxytoluene ( bht ), propyl gallate ( pg ), butylhydroxyanisol ( bha ), ascorbic acid , sodium ascorbate , erythorbic acid , sodium nitrite , sodium bisulfite , sodium pyrosulfite , citric acid , and edetate sodium ; bht , pg , and sodium ascorbate in another embodiment ; and bht in still another embodiment . these antioxidants may be used alone , or as an appropriate combination of two or more thereof . the content of the antioxidant with respect to the modified release portion is , for example , 0 . 025 % by weight to 0 . 25 % by weight . as another embodiment , the content of the antioxidant per formulation is 0 . 015 % by weight to 0 . 15 % by weight . a stabilizer may be contained in the modified release portion in the present invention . when polyethylene oxide is used as the hydrogel - forming polymer , the stabilizer is not particularly limited , so long as it does not periodically change the release properties of the drug . examples of the stabilizer include yellow ferric oxide , red ferric oxide , black iron oxide , and the like . these stabilizers may be used alone , or as an appropriate combination of two or more thereof . the content of the stabilizer with respect to the weight of the modified release portion is 0 . 05 % by weight to 1 % by weight . as another embodiment , the content of the stabilizer with respect to the formulation is 0 . 03 % by weight to 0 . 6 % by weight . the dissolution rate of solifenacin from the immediate release portion in the present invention is not particularly limited , so long as it shows availability in the living body equivalent to that of the current solifenacin formulation ( single drug formulation ). when a test is carried out in accordance with , for example , the dissolution test , method 2 described in the japanese pharmacopoeia ( paddle method , 50 rpm to 200 rpm ), the dissolution test , method 1 described in the japanese pharmacopoeia ( basket method , 50 rpm to 200 rpm ), the dissolution test ( paddle method ) described in the united states pharmacopeia , the dissolution test ( basket method ) described in the united states pharmacopeia , or the like , it is defined as follows : ( 1 ) after 15 minutes , 85 % or more of a drug is dissolved , and 90 % or more is dissolved in another embodiment , ( 2 ) after 30 minutes , 90 % or more of a drug is dissolved , and 95 % or more is dissolved in another embodiment , and ( 3 ) after 60 minutes , 90 % or more of a drug is dissolved , 95 % or more is dissolved in another embodiment , and 97 % or more is dissolved in still another embodiment . another embodiment of the test method is the dissolution test , method 1 described in the japanese pharmacopoeia ( basket method , 100 rpm ). the dissolution rate of solifenacin from the immediate release portion is defined , from these dissolution rates ( 1 ), ( 2 ), and ( 3 ), alone , or as a combination of two or more . the maximum percentage of solifenacin dissolution from the immediate release portion in the present invention is not particularly limited , so long as it shows availability in the living body equivalent to that of the current solifenacin formulation ( single drug formulation ). when a test is carried out in accordance with , for example , the dissolution test , method 2 described in the japanese pharmacopoeia ( paddle method , 50 rpm to 200 rpm ), the dissolution test , method 1 described in the japanese pharmacopoeia ( basket method , 50 rpm to 200 rpm ), the dissolution test ( paddle method ) described in the united states pharmacopeia , the dissolution test ( basket method ) described in the united states pharmacopeia , or the like , it is defined by a drug dissolution rate after 60 minutes . as another embodiment , when a test is carried out in accordance with the dissolution test , method 1 described in the japanese pharmacopoeia ( basket method , 100 rpm ), it is defined by a drug dissolution rate after 60 minutes . the maximum percentage of solifenacin dissolution from the immediate release portion is defined as that the drug dissolution rate after 60 minutes is 90 % or more , that the drug dissolution rate after 60 minutes is 92 % or more in another embodiment , that the drug dissolution rate after 60 minutes is 95 % or more in still another embodiment , and that the drug dissolution rate after 60 minutes is 97 % or more in still another embodiment . a filler and / or a binder contained in the immediate release portion to be used in the present invention are not limited , so long as they are pharmaceutically acceptable , and pharmacologically acceptable . examples of the filler and / or the binder include lactose , d - mannitol , maltose , polyethylene glycol , polyvinyl pyrrolidone , hypromellose , and hydroxypropylcellulose . as another embodiment , d - mannitol , maltose , polyethylene glycol , and polyvinyl pyrrolidone are exemplified . as still another embodiment , d - mannitol and maltose , and d - mannitol and hydroxypropylcellulose are exemplified . examples of the polyethylene glycol include , for example , peg 400 , peg 1500 , peg 4000 , peg 6000 , and peg 20000 ( product names , manufactured by nof corporation )]. examples of the polyvinyl pyrrolidone include , for example , kollidon k25 and kollidon k90 ( product names , manufactured by basf ), and the like . the content of the filler and / or the binder contained in the immediate release portion , with respect to the weight of the immediate release portion , is , for example , 5 % by weight to 99 % by weight , 40 % by weight to 99 % by weight in another embodiment , 80 % by weight to 99 % by weight in still another embodiment , and 90 % by weight to 99 % by weight in still another embodiment . the content of the filler and / or the binder contained in the immediate release portion , with respect to the weight of the formulation , is 5 % by weight to 50 % by weight as an embodiment , 10 % by weight to 40 % by weight as another embodiment , 20 % by weight to 40 % by weight as still another embodiment , and 30 % by weight to 40 % by weight as still another embodiment . these fillers and / or binders may be used alone , or as an appropriate combination of two or more thereof . calcium stearate contained in the immediate release portion to be used in the present invention is not particularly limited , so long as it conforms to the standards of the japanese pharmacopoeia , the united states pharmacopeia , the european pharmacopoeia , or the like . for example , parteck ( trademark ) lub cst ( product name , manufactured by merck ) may be exemplified . the content of calcium stearate with respect to the weight of the immediate release portion is , for example , 0 . 1 % by weight to 10 % by weight , 0 . 5 % by weight to 3 . 0 % by weight as another embodiment , 0 . 5 % by weight to 2 . 0 % by weight as still another embodiment , and 0 . 5 % by weight to 1 . 5 % by weight as still another embodiment . the content of calcium stearate with respect to the weight of the formulation is 0 . 05 % by weight to 6 % by weight , and 0 . 2 % by weight to 1 % by weight as another embodiment . various pharmaceutical additives may be appropriately used to prepare the pharmaceutical composition for oral administration of the present invention , if desired , and are not particularly limited , so long as they are pharmaceutically and pharmacologically acceptable . examples of the pharmaceutical additive include a filler , a binder , a disintegrating agent , an acidulant , an effervescent agent , an artificial sweetener , a flavor , a coloring agent , a buffer , an antioxidant , a surfactant , and the like . examples of the filler to be used in the modified release portion include lactose , sucrose , d - mannitol , d - sorbitol , starch , gelatinized starch , dextrin , crystalline cellulose , low substituted hydroxypropylcellulose , carboxymethylcellulose sodium , gum arabic , dextrin , pullulan , light anhydrous silicic acid , synthetic aluminum silicate , magnesium aluminate metasilicate , and the like . examples of the binder to be used in the modified release portion include gum arabic , hypromellose , hydroxypropylcellulose , hydroxyethylcellulose , and the like . examples of the disintegrating agent include corn starch , potato starch , carmellose calcium , carmellose sodium , low - substituted hydroxypropylcellulose , and the like . examples of the acidulant include citric acid , tartaric acid , malic acid , and the like . examples of the artificial sweetener include saccharin sodium , dipotassium glycyrrhizinate , aspartame , stevia , thaumatin , and the like . examples of the flavor include lemon , lemon - lime , orange , menthol , and the like . examples of the coloring agent include food yellow no . 4 , food yellow no . 5 , food red no . 3 , food red no . 102 , food blue no . 3 , and the like . examples of the buffer include citric acid , succinic acid , fumaric acid , tartaric acid , ascorbic acid , and salts thereof ; glutamic acid , glutamine , glycine , aspartic acid , alanine , arginine , and salts thereof ; and magnesium oxide , zinc oxide , magnesium hydroxide , phosphoric acid , boric acid , and salts thereof . examples of the antioxidant include ascorbic acid , dibutyl hydroxytoluene , propyl gallate , and the like . examples of the surfactant include polysorbate 80 , sodium laurylsulfate , polyoxyethylene hydrogenated castor oil , and the like . these pharmaceutical additives may be appropriately added alone , or as a combination of two or more thereof , in an appropriate amount . with respect to the contents , each pharmaceutical additive may be contained in an amount such that the desired effects of the present invention may be achieved . as the pharmaceutical composition ( formulation ) for oral administration of the present invention , a single formulation ( combined formulation ) prepared by a known method per se , such as a pharmaceutical composition for oral administration containing a layer comprising mirabegron or a pharmaceutically acceptable salt thereof and a layer comprising solifenacin or a pharmaceutically acceptable salt thereof , may be exemplified . as another embodiment , multi - layered tablets , such as a bi - layered tablet in which a layer comprising mirabegron or a pharmaceutically acceptable salt thereof and a layer comprising solifenacin or a pharmaceutically acceptable salt thereof are laminated , a multi - layered tablet in which a plurality of a layer ( s ) comprising mirabegron or a pharmaceutically acceptable salt thereof and a layer ( s ) comprising solifenacin or a pharmaceutically acceptable salt thereof are laminated , and a three - layered tablet in which a drug - free layer is sandwiched between a layer comprising mirabegron or a pharmaceutically acceptable salt thereof and a layer comprising solifenacin or a pharmaceutically acceptable salt thereof ; a dry - coated tablet having a modified release portion comprising mirabegron or a pharmaceutically acceptable salt thereof as an internal core and an immediate release portion comprising solifenacin or a pharmaceutically acceptable salt thereof as an outer layer ; and a film - coated tablet in which a modified release portion comprising mirabegron or a pharmaceutically acceptable salt thereof as a core is coated with an immediate release portion comprising solifenacin or a pharmaceutically acceptable salt thereof by film coating , may be exemplified . as still another embodiment , a bi - layered tablet in which a layer comprising mirabegron or a pharmaceutically acceptable salt thereof and a layer comprising solifenacin or a pharmaceutically acceptable salt thereof are laminated , may be exemplified . in the layer comprising mirabegron or a pharmaceutically acceptable salt thereof , a substance or two or more substances selected from the group consisting of a hydrogel - forming polymer , a hydrophilic base , an antioxidant , a stabilizer , and a pharmaceutical additive may be contained . as these substances , the above - mentioned substances may be used . in the layer comprising solifenacin or a pharmaceutically acceptable salt thereof , a substance or two or more substances selected from the group consisting of a filler , a binder , calcium stearate , and a pharmaceutical additive may be contained . as these substances , the above - mentioned substances may be used . hereinafter the process of manufacturing the pharmaceutical composition for oral administration of the present invention will be explained in detail . the pharmaceutical composition for oral administration of the present invention may be produced by appropriately combining known methods per se . an apparatus and a method used in the pulverizing step are not particularly limited , so long as drugs and appropriate pharmaceutical additives can be pharmaceutically pulverized . examples of the apparatus include a hammer mill , a ball mill , a jet mill , a colloid mill , and the like . the conditions for pulverization may be appropriately selected and are not particularly limited . an apparatus and a method used in the mixing step subsequent to the pulverizing step are not particularly limited , so long as components can be uniformly mixed pharmaceutically . an apparatus and a method used in this step are not particularly limited , so long as the hydrogel - forming polymer and the like can be granulated . examples of a granulation method and a granulation apparatus include a high - speed agitation granulation method , a pulverization granulation method , a fluidized bed granulation method , an extrusion granulation method , a tumbling granulation method , and a spray granulation method ; and apparatuses used in these methods . a fluidized bed granulation method and apparatus may be used in another embodiment , and a tumbling fluidized bed granulation method and apparatus may be used in still another embodiment . the resulting granulated product may be dried . the drying method is not particularly limited , so long as the granulated product can be pharmaceutically dried . an apparatus and a method used in this step are not particularly limited , so long as the drugs and the like can be granulated . examples of a producing method and a producing apparatus include a fluidized bed granulation method , a melting granulation , a high - speed agitation granulation method , a pulverization granulation method , an extrusion granulation method , a tumbling granulation method , a spray granulation method , and a dry granulation method ; and apparatuses used in these methods . a fluidized bed granulation method and apparatus may be used in another embodiment . binders used in wet granulation may be used alone , or as an appropriate combination of two or more thereof . in the spray granulation method , the resulting granulated product may be dried . the drying method is not particularly limited , so long as the granulated product can be pharmaceutically dried . an apparatus and a method used in this step are not particularly limited , so long as the pharmaceutical composition for oral administration of the present invention can be formed . examples of the method include : a method in which the drugs and appropriate pharmaceutical additives are mixed without granulation and drying , and directly compression - molded to obtain tablets ; a method in which the granulation step is carried out , a lubricant is added to the resulting granulated product , and the mixture is compression - molded to obtain tablets ; a method of preparing bi - layered tablets by laminating the modified release portion and the immediate release portion ; a method of preparing multi - layered tablets by laminating a plurality of the modified release portion ( s ) and the immediate release portion ( s ); a method of preparing multi - layered tablets by adding a drug - free layer between the modified release portion and the immediate release portion ; and a method of preparing dry - coated tablets having the modified release portion as an internal core and the immediate release portion as an outer layer . as another embodiment , a method of preparing bi - layered tablets may be exemplified . examples of a tableting machine include a multi - layered rotary tableting machine , an oil press , and the like . the conditions for tableting , such as a tableting pressure , are not particularly limited , so long as bi - layered tablets and / or multi - layered tablets can be prepared . when bi - layered tablets are prepared , a granulated product for the first layer and another granulated product for the second layer are laminated , and compressed under a tableting pressure of approximately 2 kn to approximately 20 kn to prepare the bi - layered tablets . in another embodiment , a granulated product for the first layer is compressed under a tableting pressure of approximately 0 . 1 kn to approximately 10 kn , and another granulated product for the second layer is placed on the first layer and compressed under a tableting pressure of approximately 2 kn to approximately 20 kn to prepare the bi - layered tablets . when multi - layered tablets are prepared , a tableting pressure can be appropriately adjusted to carry out the compression . the hardness of the resulting tablet is not particularly limited , so long as the tablet is not damaged during the manufacturing process , the distribution process , and the like . the hardness may be , for example , 40 n to 200 n . the method of film coating is not particularly limited , so long as the tablets can be pharmaceutically coated . examples of the coating include pan coating , dip coating , and the like . film coating agents may be added alone , or as a combination of two or more thereof , in an appropriate amount . the coating rate is not particularly limited , so long as a film can be formed . the coating rate is , for example , 1 % to 10 %. when a core comprising the modified release portion is coated with the immediate release portion to prepare film coated tablets , a spray liquid prepared by dissolving and / or dispersing the components of the immediate release portion in a solvent such as water may be sprayed on the core to obtain the film coated tablets . the coating rate is not particularly limited , so long as the film comprising the immediate release portion can be formed . the coating rate is , for example , 1 % to 20 %, or the like . after the film coating , the resulting film coated tablets may be dried . the drying method is not particularly limited , so long as the film coated tablets can be pharmaceutically dried . the conditions for drying are not particularly limited , so long as they are appropriately selected in view of , for example , the stability of the formulation . the initial water content after film coating is preferably 0 . 1 % to 2 % in accordance with , for example , the stability . the pharmaceutical composition for oral administration of the present invention may be used as a pharmaceutical composition for treating urinary urgency , urinary frequency , and / or urge urinary incontinence associated with overactive bladder . the process of manufacturing the pharmaceutical composition for oral administration of the present invention includes , in addition to the above - mentioned methods , methods of producing a pharmaceutical composition by appropriately combining known methods per se . the present invention will be further illustrated by , but is by no means limited to , the following examples , comparative examples , referential examples , and experimental examples . after 6 . 0 parts of mirabegron was pulverized , using a screen mill ( comil , manufactured by powrex corporation ), together with 16 . 8 parts of polyethylene oxide ( polyox ( registered trademark ) n - 60k , manufactured by dow , the same compound was used in the following examples . ), 34 . 7 parts of polyethylene glycol 8000 ( polyglykol 8000pf , manufactured by clariant , the same compound was used in the following examples . ), and 1 . 8 parts of hydroxypropylcellulose ( hpc - sl , manufactured by nippon soda co . ltd ., the same compound was used in the following examples . ), the resulting pulverized powder was loaded into a fluidized bed granulating apparatus ( gpcg - 120 , manufactured by powrex corporation ), and granulated by spraying 6 . 7 parts of water . with 59 . 3 parts of the dried granulated product , 0 . 1 parts of butylhydroxytoluene ( dibutylhydroxytoluene , manufactured by merck / emd , the same compound was used in the following examples .) and 0 . 6 parts of magnesium stearate ( parteck ( registered trademark ) lub mst , manufactured by merck , the same compound was used in the following examples .) were mixed to obtain mixed powder for a modified release portion . a spray liquid was prepared by dissolving 4 . 0 parts of maltose ( sunmalt s , manufactured by sanwa starch co ., ltd ., the same compound was used in the following examples .) in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( gpcg - 1 , manufactured by powrex ), 0 . 6 parts of solifenacin succinate was loaded , together with 35 parts of mannitol ( pearitol 50c , manufactured by roquette , the same compound was used in the following examples . ), and granulated by spraying the spray liquid . with the 39 . 6 parts of the dried granulated product , 0 . 4 parts of calcium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine ( autograph ags - 20kng , manufactured by shimadzu corporation , the same apparatus was used in the following examples . ), 60 parts of the mixed powder for a modified release portion and 40 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 2 . 5 mg of solifenacin succinate . as a referential example , the mixed powder for an immediate release portion was formed into tablets to obtain a single drug formulation consisting of an immediate release portion . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 1 . 2 parts of hydroxypropylcellulose in 10 . 8 parts of water while stirring . into a fluidized bed granulating apparatus ( flo - 01 , manufactured by freund corporation ), 0 . 6 parts of solifenacin succinate was loaded , together with 37 . 8 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 6 parts of the dried granulated product , 0 . 4 parts of calcium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 60 parts of the mixed powder for a modified release portion and 40 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 2 . 5 mg of solifenacin succinate . as a referential example , the mixed powder for an immediate release portion was formed into tablets to obtain a single drug formulation consisting of an immediate release portion . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 1 parts of water while stirring . into a fluidized bed granulating apparatus ( flo - 01 , manufactured by freund corporation ), 1 . 2 parts of solifenacin succinate was loaded , together with 34 . 5 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 7 parts of the dried granulated product , 0 . 2 parts of calcium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 60 . 1 parts of the mixed powder for a modified release portion and 39 . 9 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 5 mg of solifenacin succinate . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( gpcg - 15 , manufactured by powrex ), 1 . 2 parts of solifenacin succinate was loaded , together with 34 . 4 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 6 parts of the dried granulated product , 0 . 4 parts of calcium stearate was mixed to obtain mixed powder for an immediate release portion . using a tri - layered tableting machine ( ht - cvx45ls - uw / 3lvtt , manufactured by hata iron works co ., ltd . ), 60 parts of the mixed powder for a modified release portion and 40 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 5 mg of solifenacin succinate . as a referential example , the mixed powder for an immediate release portion was formed into tablets , using an oil press tableting machine , to obtain a single drug formulation consisting of an immediate release portion . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( flo - 01 , manufactured by freund corporation ), 1 . 2 parts of solifenacin succinate was loaded , together with 34 . 3 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 5 parts of the dried granulated product , 0 . 6 parts of calcium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 59 . 9 parts of the mixed powder for a modified release portion and 40 . 1 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 5 mg of solifenacin succinate . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( flo - 01 , manufactured by freund corporation ), 1 . 2 parts of solifenacin succinate was loaded , together with 34 . 2 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 4 parts of the dried granulated product , 0 . 8 parts of calcium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 59 . 8 parts of the mixed powder for a modified release portion and 40 . 2 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 5 mg of solifenacin succinate . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 15 . 9 parts of water while stirring . into a fluidized bed granulating apparatus ( flo - 01 , manufactured by freund corporation ), 1 . 2 parts of solifenacin succinate was loaded , together with 34 . 1 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 3 parts of the dried granulated product , 1 . 2 parts of calcium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 59 . 5 parts of the mixed powder for a modified release portion and 40 . 5 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 5 mg of solifenacin succinate . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( gpcg - 1 , manufactured by powrex ), 0 . 6 parts of solifenacin succinate was loaded , together with 35 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 6 parts of the dried granulated product , 0 . 4 parts of magnesium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 60 parts of the mixed powder for a modified release portion and 40 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration of the present invention containing 25 mg of mirabegron and 2 . 5 mg of solifenacin succinate . as a referential example , the mixed powder for an immediate release portion was formed into tablets to obtain a single drug formulation consisting of an immediate release portion . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( gpcg - 1 , manufactured by powrex ), 0 . 6 parts of solifenacin succinate was loaded , together with 35 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 6 parts of the dried granulated product , 0 . 4 parts of sodium stearyl fumarate ( pruv ( registered trademark ), manufactured by rettenmaier japan co ., ltd .) was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 60 parts of the mixed powder for a modified release portion and 40 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration for comparison containing 25 mg of mirabegron and 2 . 5 mg of solifenacin succinate . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( flo - 01 , manufactured by freund corporation ), 1 . 2 parts of solifenacin succinate was loaded , together with 34 . 4 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 6 parts of the dried granulated product , 0 . 4 parts of magnesium stearate was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 60 parts of the mixed powder for a modified release portion and 40 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration for comparison containing 25 mg of mirabegron and 5 mg of solifenacin succinate . as a referential example , the mixed powder for an immediate release portion was formed into tablets to obtain a single drug formulation consisting of an immediate release portion . a modified release portion was obtained under the same formulation and production conditions as those described in example 1 . a spray liquid was prepared by dissolving 4 . 0 parts of maltose in 16 . 0 parts of water while stirring . into a fluidized bed granulating apparatus ( flo - 01 , manufactured by freund corporation ), 1 . 2 parts of solifenacin succinate was loaded , together with 34 . 4 parts of mannitol , and granulated by spraying the spray liquid . with the 39 . 6 parts of the dried granulated product , 0 . 4 parts of sodium stearate ( sodium stearate , manufactured by nacalai tesque , inc .) was mixed to obtain mixed powder for an immediate release portion . using an oil press tableting machine , 60 parts of the mixed powder for a modified release portion and 40 parts of the mixed powder for an immediate release portion were formed into bi - layered tablets , to obtain a pharmaceutical composition ( bi - layered tablets ) for oral administration for comparison containing 25 mg of mirabegron and 5 mg of solifenacin succinate . as a referential example , the mixed powder for an immediate release portion was formed into tablets to obtain a single drug formulation consisting of an immediate release portion . the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in examples 1 and 2 , and comparative examples 1 and 2 were subjected to a dissolution test carried out in accordance with the dissolution test , method 1 ( basket method , 100 rpm ) described in the japanese pharmacopoeia . as a test fluid , 900 ml of water was used . the dissolution rates of solifenacin after 15 minutes , 30 minutes , and 60 minutes from the beginning of the test were evaluated by an hplc method . the results of the dissolution test for solifenacin are shown in table 1 . the dissolution rate of solifenacin and the maximum percentage of solifenacin dissolution from the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in comparative examples 1 and 2 were lower than those of the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in examples 1 and 2 . the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in examples 3 to 7 , and comparative examples 3 and 4 were subjected to a dissolution test carried out in accordance with the dissolution test , method 1 ( basket method , 100 rpm ) described in the japanese pharmacopoeia . as a test fluid , 900 ml of a usp phosphate buffer ( ph 6 . 8 ) was used . the dissolution rates of solifenacin after 15 minutes , 30 minutes , and 60 minutes from the beginning of the test were evaluated by an hplc method . the results of the dissolution test for solifenacin are shown in table 2 . the dissolution rate of solifenacin and the maximum percentage of solifenacin dissolution from the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in comparative examples 3 and 4 were lower than those of the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in examples 3 to 7 . with respect to the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in example 1 and comparative example 1 , productivity in tableting ( presence or absence of sticking ), and lamination , which is a problem specific to laminated tablets , were evaluated by visual observation . the results of the evaluation are shown in table 3 . in the pharmaceutical composition prepared in example 1 , the failures in tableting , i . e ., sticking and lamination , were not observed . with respect to the pharmaceutical compositions ( bi - layered tablets ) for oral administration prepared in example 1 and comparative example 1 , a change in appearance ( coloration of the immediate release portion ) during storage was periodically evaluated by visual observation . the results of the evaluation are shown in table 4 . in the pharmaceutical composition prepared in example 1 , the coloration of the immediate release portion was not observed . with respect to the immediate release portions ( single drug formulations ) of the pharmaceutical compositions for oral administration prepared , as reference examples , in examples 1 , 2 , and 4 and comparative examples 1 , 3 , and 4 , a disintegration time thereof was measured in accordance with the disintegration test , described in the japanese pharmacopoeia , in order to confirm the disintegration time . the results of the measurement are shown in table 5 . all the immediate release portions ( single drug formulations ) of the pharmaceutical compositions for oral administration prepared in examples 1 , 2 , and 4 and comparative examples 1 , 3 , and 4 disintegrated within 300 seconds . the immediate release portions ( single drug formulations ) of the pharmaceutical compositions for oral administration prepared , as reference examples , in examples 1 and 2 and comparative example 1 were subjected to a dissolution test carried out in accordance with the dissolution test , method 1 ( basket method , 100 rpm ) described in the japanese pharmacopoeia . as a test fluid , 900 ml of water was used . the dissolution rates of solifenacin after 15 minutes , 30 minutes , and 60 minutes from the beginning of the test were evaluated by a uv method . the results of the dissolution test for solifenacin are shown in table 6 . the immediate release portions ( single drug formulations ) of the pharmaceutical compositions for oral administration prepared in examples 1 and 2 and comparative example 1 showed similar dissolution rates of solifenacin and similar maximum percentages of solifenacin dissolution . the immediate release portions ( single drug formulations ) of the pharmaceutical compositions for oral administration prepared , as reference examples , in example 4 and comparative examples 3 and 4 were subjected to a dissolution test carried out in accordance with the dissolution test , method 1 ( basket method , 100 rpm ) described in the japanese pharmacopoeia . as a test fluid , 900 ml of a usp phosphate buffer ( ph 6 . 8 ) was used . the dissolution rates of solifenacin after 15 minutes , 30 minutes , and 60 minutes from the beginning of the test were evaluated by a uv method . the results of the dissolution test for solifenacin are shown in table 7 . the immediate release portions ( single drug formulations ) of the pharmaceutical compositions for oral administration prepared in example 4 and comparative examples 3 and 4 showed similar dissolution rates of solifenacin and similar maximum percentages of solifenacin dissolution . the present invention provides a pharmaceutical composition for oral administration comprising a modified release portion containing mirabegron or a pharmaceutically acceptable salt thereof , and an immediate release portion containing solifenacin or a pharmaceutically acceptable salt thereof . the pharmaceutical composition for oral administration of the present invention exhibits a drug release rate similar to those of the current formulations ( single drug formulations ), and thus , can be used as a formulation technique which provides a single formulation ( a combined formulation ) capable of expecting pharmacological effects equivalent to those of the current formulations ( single drug formulations ). although the present invention has been described with reference to specific embodiments , various changes and modifications obvious to those skilled in the art are possible without departing from the scope of the appended claims .
in order to provide the medical field with a single formulation comprising a modified release portion containing mirabegron or a pharmaceutically acceptable salt thereof and an immediate release portion containing solifenacin or a pharmaceutically acceptable salt thereof , a single formulation having dissolution rates of both drugs similar to those of the current single drug formulations is provided , and a single formulation having maximum percentages of dissolution of both drugs of 90 % or more , and having a bioavailability equivalent to those of the current single drug formulations . further , in order to provide a single formulation , a single formulation having good productivity whereby failures in tabletting are reduced , and having good storage stability whereby the coloration of the immediate release portion is suppressed is provided . the pharmaceutical composition for oral administration of the present invention contains a modified release portion comprising mirabegron or a pharmaceutically acceptable salt thereof , and an immediate release portion comprising solifenacin or a pharmaceutically acceptable salt thereof , and calcium stearate .